Trachoma

738 Statistics and geographical distribution. 740 Trachoma as a socio-domestic disease. 752 Trachoma, trachoma (from Greek trachys - rough, uneven) (syn. conjunctivitis trachomatosa, s. granulosa), a chronic infectious disease of the conjunctiva, characterized by widespread infiltration of its adenoid tissue with the formation of follicles, their subsequent degeneration, disintegration, and scarring. Trachoma at the same time is a socio-domestic disease, in its origin and development connected with certain socio-domestic conditions, the elimination of which and the struggle against which form the basis for the prevention of this process. Historical data. Trachoma has been known since ancient times. In Egypt it existed many centuries before the Christian era and continues to this day to have enormous prevalence. Therefore, Tr. was also called Egyptian inflammation of the eyes (ophthalmia aegyptica). The well-known historian of ophthalmology Hirschberg points out that from the numerous literary sources of ancient times (Plato, Plutarch, Galen, etc.) it is evident that the Greeks knew about the contagious nature of Tr. more than 2,000 years ago. The name "trachoma" first appears in Dioscorides in the first century of the Christian era. In Japan, according to Miyashita, Tr. has been known for no less than 1,200 years. In Europe, its appearance is connected with Napoleon's expedition to Egypt in 1798, but it is more correct to assume that Tr. existed in Europe even before the Napoleonic wars and only received particular prevalence in the era of Napoleon. Spread¹ of Tr. among troops during the war gave rise to calling it ophthalmia bellica, s. militaris. There is reason to believe that Tr. in Russia existed long before Napoleon's invasion. At least, some historical materials contain indications of the existence of Tr. as early as the 17th century. Etiology. Despite the century-long history of trachoma, its essence is still understood differently. There are two views, which are still opposing each other, the so-called unitary and dualistic. Dualists consider Tr. as a process of an infectious nature, differing from other follicular processes in its origin, course, and outcome. At the same time, unitarists, despite the various shades of their views on Tr., deny it a separate place among other follicular diseases of the conjunctiva, deny infection as the sole cause of Tr. * Disagreements are explained mainly by the fact that the etiology of Tr. has not yet been established, although attempts to find its causative agent have occupied the minds of researchers since ancient times and continue to the present day. The first bacteriological studies of Tr. date back to the 1880s, and from then until the beginning of the 1890s, there was a continuous appearance of a series of discoveries, first of the trachoma coccus, then of the trachoma bacillus (Trachomoccus Michel-Sattler's, Trachombacillus Muller's, etc.), but all these findings were short-lived; their etiological significance was quickly rejected. And only from 1907, since the discovery by Prowazek and Halberstädter of special intracellular inclusions in trachoma, the question of etiology entered a new phase [Vol. VII (pp. 303-304), Fig. 6]. Through systematic examination of the conjunctiva of trachoma patients, using staining of scrapings from the surface of the conjunctiva according to Giemsa, they were able to establish that within the epithelial cells near the nucleus in the light-blue protoplasm, blue inhomogeneous inclusions are observed. Among the bluish contents, red or violet small, barely recognizable coccal-like formations are visible, which have a tendency to fold in two (see table to article Blennorrhea). These diplococci bodies, not exceeding 0.25 μ in size, Prowazek and Halberstädter consider as parasites that have penetrated the epithelial cell. The uneven masses of inclusions they take as products of the cell's reaction (plastin) due to the penetration of the parasite. The found formations Prowazek and Halberstädter attribute to the so-called Chlamydozoa. The research of these authors became the starting point for numerous works on intracellular inclusions, and at present there is already an extensive literature devoted to clarifying the significance of these inclusions for Tr. For the morphological characterization of the inclusions, or as they are called, Prowazek-Halberstädter trachoma bodies, substantial data were added in subsequent studies. Lindner distinguishes in the inclusions so-called initial bodies and elementary bodies (Initialkörper, Elementarkörperchen), which, in his opinion, belong to different stages of development of the parasite. The finding of intracellular inclusions in Tr. was confirmed by the vast majority of researchers, but the very first observations showed that inclusions in Tr. are not a regular phenomenon - they are most often found in fresh, untreated cases of Tr. Axenfeld in his monograph (1914) on the etiology of Tr. believed that inclusions are found in 52% of fresh cases, and in late periods only in 12%. In recent years, with the refinement of research techniques, their presence is noted by many with greater constancy. There are authors (Taborysky) who claim that inclusions can be found in every case of fresh Tr. It is unanimously recognized that inclusions are found mainly in the epithelium of the conjunctiva, and there are only rare indications of their presence in the epithelium of the cornea in pannus. The etiological significance of inclusions for Tr. the first researchers saw primarily in the fact that they were not found in control studies of normal conjunctiva in its various inflammations. A fact confirming the specificity of the inclusions was their finding in the initial stage in experimental Tr. of animals (monkeys) and humans. However, the recognition of the specificity of the inclusions subsequently encountered objections, besides Tr. they were found in a special form of blennorrhea of newborns (see Blennorrhea), then in the so-called swimming pool or basin conjunctivitis (see), and in rare follicular lesions, which by their picture resemble Tr. and are now combined by Lindner's school into a general group of conjunctival diseases with inclusions (Einschlusskrankheiten). The question of the nature of the inclusions and their role in Tr. has caused a lively discussion throughout the history of inclusions, and it cannot be considered resolved at the present time. Despite a number of gaps in the doctrine of the nature of Prowazek-Halberstädter bodies, many researchers still consider these formations the causative agent of Tr., attributing to them a parasitic origin (Lindner, Lewenstein, Taborysky, etc.). However, direct proof of this has not yet been obtained. No one has yet succeeded in obtaining a culture of these inclusions and the supposed causative agent within them. With the unclear etiological role of the inclusions, they still have a certain differential diagnostic value. Finding them in doubtful cases of follicular processes sometimes allows one to delineate trachoma from ordinary follicular catarrh. In recent years, the attention of ophthalmologists has been drawn to a new very important discovery by the bacteriologist Noguchi. In 1927, Noguchi succeeded in isolating from the conjunctiva of trachoma patients a special type of bacillus, named by him Bact. granulosis. The Noguchi bacillus is characterized by the following morphological-biological features. It is 0.8 to 1.4 μ in length and 0.25-0.3 μ in thickness. It is Gram-negative, motile, grows best on a semi-solid medium, the so-called medium for leptospires (Leptospira-medium), containing fresh blood serum and hemoglobin (8 parts of 0.9% NaCl, 1 part of fresh rabbit serum, 1 part of 2% agar; to this is added 0.1 part of lacquered rabbit red blood cells). On this medium, the Noguchi bacillus grows at 30°, but it grows equally well up to 37°. Besides the medium for leptospires, the bacillus occasionally grows on blood agar. The pathogenic significance of the isolated microbe was tested by Noguchi and many other researchers on monkeys. A pure culture, inoculated subconjunctivally into monkeys or after scarification of the conjunctiva, in most cases caused the development of chronic granular conjunctivitis, slowly progressive and at its height resembling human Tr. Noguchi succeeded in transferring the bacillus from one monkey to another. On the basis of his observations, Noguchi considers the bacillus the causative agent of Tr. However, numerous verification observations do not allow, even at the present time, to arrive at a definite conclusion about the etiological significance of Bact. granulosis. Among researchers, there is different interpretation of the clinical picture of experimentally induced Tr. in animals. Some, like Olitsky and his school, claim that in monkeys, with the Noguchi bacillus culture, a specific trachomatous disease is caused, others, like Lindner, Wilson, Weiss, Finnoff, and Thygeson, etc., with great categoricity deny the evidence of inoculations of the bacillus into the conjunctiva of animals. Undoubtedly, of great importance for recognizing the etiological significance of the bacillus are experiments with inoculation of the culture into humans.

Footnote 1: The spread of trachoma among troops during the war gave rise to calling it ophthalmia bellica, s. militaris.

By 1934, quite a number of such experiments had been conducted (over 30 published), and in the overwhelming majority they had a negative result, and those cases that the authors accepted as positive, with the exception of isolated ones, raise serious objections to the correctness of their interpretation. Some researchers, led by Lindner, having isolated a rod similar in its morphological-biological properties to Bact. granulosis from the conjunctiva in follicular catarrh, suggest that the Nogushi bacillus is not the cause of T., but of follicular catarrh. But even this view cannot be considered proven, since there are observations that contradict Lindner's hypothesis (Finn and Tigesson). Among the evidence of the etiological significance of the Nogushi bacillus, observations regarding the filterability of the trachoma virus and the Nogushi bacillus are of interest. The trachoma virus was considered until recently a filterable virus, since infection with a filtrate from trachomatous material gives a positive result, but recent experiments by Trepezontsova, Olitsky, and others allow one to doubt the established view of the filterability of the trachoma virus. The filterability of the Nogushi bacillus is also denied. Attempts were made to find confirmation of the specificity of Bact. granulosis in serological and allergic skin reactions, but they also give contradictory results. Thus the question of the Nogushi bacillus remains open to this day. Epidemiology. T. does not belong to highly infectious diseases, its transmission occurs through contact, and the infectious material consists of pus, mucus, and the tear fluid of a trachomatous eye. The relatively low stability of the T. virus to physical agents has been established. It is destroyed when heated to 50° for 1/2 hour, and drying at 32° for 1/8 hour also deprives it of its infectious properties. But, on the other hand, it retains its infectiousness after prolonged (7 days) exposure at ice temperature. The infection is introduced by contaminated hands, objects that have come into contact with infectious material. It turned out, according to experiments by Nicolas, that flies can also be transmitters of the infection. Coming into contact with the tears and pus of a trachomatous eye, flies carry the infection to a healthy eye, which easily occurs during sleep, especially in children. The use of a common towel in the family for wiping the face, washing in a common basin, and using common bedding has special epidemiological significance. The role of a common towel in the infection and spread of T., especially among the rural population, has long been known. In the past, the usual practice was not to use a towel, but simply a rag from old linen, with which all family members wiped their faces, as a result of which secretions from diseased eyes got into healthy ones and infected them. And such a domestic feature as the use of a common washing basin has more than once manifested itself as a striking cause of the spread of T., sometimes overshadowing immeasurably more powerful factors. Markov, examining T. among the Volga Germans in 1911, was able to note that among the Germans, although economically stronger and undoubtedly more cultured compared to the surrounding Russian population, the percentage of trachomatous individuals is significantly higher, which is primarily connected with the application of 'the ancestral German custom of the family washing from the same basin, in a number of cases without changing the water'. T. is a kind of 'family disease': when one family member is infected, it usually, with their close contact, also infects other members. The same thing happens under unsanitary conditions when trachomatous individuals live together with healthy ones in dormitories, barracks, prisons, etc. The spread of T. in schools is usually due to its introduction from the family. T. spares no age, sex, or nation. The most favored age for infection is childhood, and the frequency of infection decreases in later ages. The following table of the distribution of T. by age and stages (in %) can serve as an illustration (the table was compiled on the basis of materials from a general examination in the former Kazan province in 1913). Age Up to 10 years..... 10-20 » ..... 20-50 » ..... Over 50 years . . . For all ages Stages of trachoma 38 16 23 From this table it is seen that the first stage of T., i.e., fresh T., is observed mainly up to 20 years, and after 20 years infections are rare. The reason for this is probably to be sought primarily in exogenous factors—in the conditions of easier contact in childhood. There is no sufficient basis to speak of a special susceptibility of children or immunity of later ages to T. The distribution of T. by sex is characterized by the predominance of T. among women. Almost every general examination in trachoma-affected areas can serve as proof of this. Thus, according to data from a general examination of the Udmurt region in 1926 (Dymshits) out of 5,687 examined trachomatous individuals, 46.6% were men, 53.4% women; many such examples can be given. The more frequent lesions of T. in women can be easily explained by domestic factors. In the conditions of peasant life, especially in the past, a woman is exposed to the possibility of infection more often than a man. She is more closely connected with the family; in the past she was less cultured, more often illiterate than a man. In any case, there is no data to consider sex a factor of an endogenous order for infection with T. The assertion of researchers about so-called racial predisposition, resp. racial immunity, must be considered completely erroneous. The fact of the more frequent spread of T. among some nationalities compared to others finds its explanation in the socio-domestic conditions of their historical life, and not in endogenous racial influences. In recent years, much attention has been paid, on the initiative of Brana and Angelucci (Brana, Angelucci), to the importance of constitution in infection with T. They attribute a dominant influence of constitution in T., establish a special type of 'pretrachomatous constitution', 'habitus trachomatosus', etc. Not denying the importance of constitution for the occurrence of trachomatous infection, there is no basis, however, to consider the presence of a certain type of constitution a mandatory prerequisite for infection. General examinations in areas of endemic spread of T. clearly indicate that T. affects individuals of various constitutions, and there is no special selective tendency of the trachomatous process toward a certain constitution (Mikaelian, Kruglov and Tarnopolsky). Statistics and geographical distribution. Trachoma in capitalist countries. Trachoma is one of the most widespread diseases of humanity, but determining the exact degree of its spread presents enormous difficulties. The materials available so far allow only an approximate discussion of the number of trachomatous individuals in bourgeois countries. The general approximate count of T. in any case gives enormous figures. Thus, Morax and Petit (Morax, Petit) believe that at least 90-100 million people are affected by T., i.e., about 1/6 of the entire human population suffers from this disease. Recently, Wibaut (1929) compiled a map of the world distribution of trachoma, which gives an idea of the wide coverage of various countries by trachoma. With regard to individual countries, Egypt can first be identified as the most affected by T. T. has been exceptionally widespread in Egypt since time immemorial. According to all available data and at present, in Egypt, up to 85-90% of the entire population is affected by T. The spread of T. is particularly great in childhood. According to Mac Callan, in schools, from 91.3% to 98.2% of affected individuals with T. were found. T. is also extremely widespread in Tripolitania and Cyrenaica, where the number of trachomatous individuals also reaches 85% (Paragsoppe). The French African colonies are also extremely affected: Tunisia, Algeria, Morocco. In southern Tunisia, for example, Petit found among the natives up to 90% affected by T., in Gabès, in Tozeur-96%, and in Nefta even 98%. In Morocco (Casablanca), among eye patients, up to 70% were found to be trachomatous. In Asia, the wide spread of T. in China should be noted. Morax and Petit believe that about 30% of the entire population of this huge country is affected by T. In some areas, the percentage of trachomatous individuals reaches 90. Japan has known T. for more than 1,000 years, and according to data by Miashita, about 20% of the population suffers from T. In British India, T. is also widespread. According to recent data, in schools it reaches 96%, among military personnel-78%. In Asia Minor, T. is strongly spread in Palestine, where, according to Ticho, 27.9% of the school population of Jerusalem is affected by T., and according to Shimkin, in Jaffa the percentage of trachomatous schoolchildren reaches 37; the total number of trachomatous individuals, according to Ticho, is 400,000. In Turkey, according to van Mellingen, trachomatous individuals constitute 15.6% of eye patients. In America, T. generally does not have a large spread, but still in some places a fairly high percentage of the population is affected. In the USA, areas along the Atlantic coast are affected. According to Davies' statistics, in New York, among a million eye diseases before measures against immigrants, about 4% were T. In subsequent years, T. fell to 2%.

American authors, as is known, denied the affliction of T. among Negroes. S. Vernett (Swan Burneth) on the basis of an examination of 13 regions of the USA speaks of a relative immunity of Negroes. At the present time, a number of researchers have established that Negroes do not represent racial immunity and among them in certain localities a considerable number of trachoma cases are encountered. There are many trachoma cases among Indians in Minnesota and especially in Oklahoma (up to 68%). Trachoma is also widely spread in New Mexico. In Canada, among eye disease patients, 3.6% are trachoma cases. Trachoma is somewhat more widespread in Cuba. Among the school population, for example, in Havana out of 3,000 children, trachoma was found in 700. In South America, trachoma is encountered more frequently in Brazil and Argentina. In Europe, trachoma is spread unevenly. In the capitalist countries of the metropole, in contrast to their colonies, as a rule have a relatively small number of trachoma cases. In England it occurs only sporadically, in Ireland it accounts for up to 2.3% among eye disease patients, in Scotland only 0.8%. In France, trachoma is encountered mainly in coastal cities; thus, in Marseille 15% of all eye disease patients are trachoma cases, in Montpellier-1.5-2.9%. In industrial cities the percentage is very insignificant, according to Petit-1.46. In Italy, trachoma is endemic in all provinces. According to an approximate count, there are about 3,000 trachoma cases in the country. In Spain, high figures of trachoma are also noted, for example in Madrid trachoma accounts for 25% of all eye diseases, and in some other cities, such as Barcelona, Cadiz, even more. In total for 22 million inhabitants there are 50,000 trachoma cases. In Holland, trachoma is concentrated mainly in Amsterdam, especially among the poor, densely living Jewish population. In schoolchildren in 1923 it was found in 3.9%. In Portugal they count up to 13% trachoma cases among eye disease patients (Gama Pinto). In Germany, the most affected area is East Prussia, where the incidence of trachoma according to the 1925 statistics reaches over 4% of the entire population. In Hungary, which is one of the old foci of trachoma in Europe, the spread of trachoma at present is insignificant. In 1928 during an examination of the population, 10,830 trachoma cases were found among 8.5 million inhabitants, in schools only 0.39% trachoma cases. In Yugoslavia there are approximately 0.5% trachoma cases among the population. In Bulgaria, up to 5,000 trachoma cases are counted for the entire country. In individual districts, 10-20% of the inhabitants are affected by trachoma. In Czechoslovakia for 13.7 million people there are 61,000 trachoma cases. Sweden, Denmark, Norway, Iceland, Greenland have negligible percentages of trachoma. The spread of trachoma in the countries bordering the USSR is of interest. Lithuania has 10% trachoma cases, Latvia-5%, Estonia-4%, Finland according to the latest information (1929) has 2% of the population affected by trachoma. In Poland, trachoma is especially widespread among the child population. In orphanages the percentage of trachoma cases reaches 20-30. In 1924 in Poland, trachoma cases constituted up to 7.2% of all eye disease patients, and in the entire Poland there were up to 300,000 of them (Zaehert). In Romania, trachoma has greatly increased after the war. In Bucharest for example, instead of 10% of all eye disease patients being trachoma cases, they now occupy 20%, and the total number of trachoma cases in the country reaches 80-90,000. The spread of trachoma in the USSR. The total number of trachoma patients in pre-revolutionary Russia in 1913 with a population of 178 million was calculated at 1,029,333 people. The actual number of trachoma patients in tsarist Russia significantly exceeded this figure, since pre-revolutionary statistics did not cover all trachoma cases due to poor registration. A definite increase year by year in the number of trachoma cases was noted, and the trachoma indicator, i.e. the number of trachoma cases per 10,000 healthy population, was increasing, outpacing population growth. In 1902 the indicator was 36.2, and in 1913 it reached 63.3. The distribution of trachoma patients in 1913 was as follows: in European Russia there were 885,789, in Asian Russia-144,094. The main material for these data was hospital statistics, which reflected primarily the population's seeking of hospital help, and did not express the true spread of trachoma, undoubtedly exceeding these official figures. This situation is illustrated by some data from mass examinations of the population for trachoma. In 1913 a mass examination of the Kazan province was carried out, which is now the territory of national republics-Tatar ASSR, Chuvash ASSR and Mari region. In 6 medical districts out of 166,000 people, 42,616 trachoma cases were found, i.e. 25.5% of the entire population. During the war years and the first years of the revolution, accounting for trachoma was not carried out in normal amounts, but from 1922 registration of trachoma was already introduced, and every year the spread of trachoma is studied in more detail. When evaluating the data obtained, it must be borne in mind that comparison of the figures we operate with at present with past data should be made with great reservations. The statistics of the past are based on a completely different healthcare system of tsarist Russia and compiled by other, far from perfect accounting methods. With a radically changed healthcare system, with significantly improved general hospital care, with special eye care covering increasingly broader masses of workers, accounting for trachoma at present is carried out with increasing accuracy and completeness of detection. In 1927 the total number of trachoma cases in the USSR was determined at 846,750 people, i.e. a sharp decrease in the number of trachoma patients (by 18%) is noted even compared to the understated figure of patients in tsarist Russia (1913). In recent years, especially during the first five-year plan, enormous shifts in the socio-domestic living conditions of the population of the Union, especially the collectivization of agriculture, and widely carried out measures by health authorities to combat trachoma, have given for this short period an even greater decrease in trachoma. In this respect, the successes achieved in the national republics, which represented the most trachoma-affected group, are particularly significant. The Chuvash ASSR, which was one of the first places, achieved the most indicative results during this time. According to materials of the Chuvash NKZdr, based on data from mass examinations, in 1932 compared to 1928, i.e. in 4 years of vigorous struggle, trachoma decreased by almost 20%. In the Mari region there is also a clear decrease in recent years. In the Udmurt region a decrease in trachoma by 10% was noted during the first five-year plan. Trachoma as a socio-domestic disease. When considering the causal factors of the spread of trachoma, the outstanding role of socio-domestic factors is clear. It is difficult to find another eye disease which throughout its history would have been a more vivid example of the dependence of its spread on exogenous factors, primarily on the influence of the social environment. Trachoma, with its exceptional spread among the most economically weak population strata, has long been known as the 'disease of the poor'. Numerous studies of the past and especially observations of the revolutionary era have provided rich material, which undoubtedly depicts how closely the spread of trachoma is connected among the working masses of those nationalities of the USSR which in the era of tsarism stood on an extremely low level of culture, were economically weak and lived in conditions of primitive domestic life. The areas of our Union inhabited by various small nationalities provide bright illustrations in this respect. Take for example the Volga-Kama region, where the Chuvash, Mari, Udmurt, Tatar, Mordovian and other nationalities, having a high prevalence of trachoma, at the same time were always in economic and cultural terms significantly weaker than other nationalities of former Russia. Against the background of economic backwardness, these nationalities always presented striking examples of their overall unculturedness and exclusively unsanitary domestic conditions. With the enormous shifts of a social and cultural nature that have occurred in recent years in the USSR, domestic orders are also sharply changing. Now with the collectivization of agriculture, before our eyes, the old peasant way of life is being broken up and at the same time incomparably better conditions are being created for combating the spread of trachoma and its elimination. Pathological anatomy. It has been 75 years since Benz first established that in the conjunctiva in trachoma numerous limited accumulations of lymphoid cells-follicles-are observed. Since that time, we have a huge number of path-histological works devoted to the study of the trachomatous process. A red thread in the works of the past is the special attention of researchers to the follicle as the most important element of the process. At present, with the application of perfect research methods, the importance of path-histological changes in trachoma as a whole, in all manifestations of the process, is particularly highlighted, and the follicle is assigned a subordinate, secondary place. The basis of the histological picture should be recognized as inflammatory changes in the mucous and submucous connective membrane, which-in severe cases-lead to extreme hypertrophy of the tissues and the development of scar changes.

This inflammation has the character of a chronic one with all its inherent features, with proliferative processes, i.e., processes of inflammatory neoplasm, coming to the forefront. For trachoma, it is characteristic that at the height of the development of the process, alongside progressive signs of inflammation, symptoms of degeneration as well as proliferation of connective tissue exist simultaneously. The processes of infiltration, in accordance with the clinical picture, have extreme diversity in strength and distribution in different parts of the conjunctiva. Where adenoid tissue is normally developed, the thickest layers of infiltration are observed—such are the transitional folds; the conjunctiva of the cartilage is affected less, is little involved in infiltration, and the conjunctiva of the eyeball is little affected. The cellular composition of infiltration has been subjected to careful study many times. A regular finding here is the presence of plasma cells. In weakly expressed forms of inflammation, they occur singly, but usually they are found in whole layers in the subepithelial tissue, sometimes extending into its deeper layers. Plasma cells are found in all stages of trachoma, especially often in the stages of papillary hypertrophy. Another and the most constant part of trachomatous infiltration are lymphocytes. They constitute the main part of the cellular infiltration in the initial stages of the process. The primary foci of inflammation consist mainly of them, and they also give the main mass of the cellular composition of the follicle. Besides these cells, histiocytes are found with great constancy, and what is particularly emphasized by some, in the first and second stages of trachoma, lymphoblasts are found in large quantities. Neutrophilic leukocytes, fat cells, eosinophils, and histiocytes are encountered much more rarely. The latter are assigned a significant role in trachomatous infiltration according to the research of recent authors (Oguchi, Eleonskaya, etc.). They are found both in the infiltration of the conjunctival stroma and in the follicles. Trachomatous follicles appear in the form of round formations, varying in their size and cellular composition, depending on the degree of development and location. The follicle consists of two sharply different parts—a peripheral zone consisting of intensely stained, densely arranged round cells, and a pale-stained center of large weakly staining cells. The marginal zone consists of lymphocytes arranged in fairly regular concentric rows and sharply delimiting the follicle from the surrounding more or less heavily infiltrated adenoid tissue. The main cellular mass of a mature follicle is formed by large or small lymphocytes. Among the lymphocytes, leukocytes (neutrophils, eosinophils, fat cells) are encountered. The central part, so-called center of multiplication (Keimzentrum), is formed by epithelioid cells. A number of recent authors believe that there are two groups of cells in the cellular composition of the center—lymphoblasts and histiocytes (according to Oguchi and others), between which various transitional forms also exist. Leukova and Dzhizhkov consider lymphoblasts the dominant element in the early stages of trachoma. They also include the epithelioid cells of the follicle among the lymphoblasts. As for other elements of the follicle, it should be mentioned that the follicle consists of a loose stroma penetrated by small vessels. The follicle has its own history of development. It basically breaks down into 3 stages: formation of the follicle, its degeneration and replacement by scar tissue, but to trace these stages in relation to each follicle seems impossible. The conditions for follicle development are too different in different parts of the conjunctiva and in different individuals, the cellular composition of the follicle is too diverse in different forms of trachoma, and the timing of the onset of degenerative and reparative processes varies in individual cases of trachomatous inflammation. The degenerative processes observed in the follicles usually go along with similar processes in the inflammatory infiltration of the tissue and undoubtedly represent one of the characteristic phenomena of trachoma. These processes are a regular consequence of trachomatous inflammation and occur at various times during its existence. Regressive phenomena will be found in marked cellular disintegration and disappearance of cellular elements, loosening of tissues, etc. The disintegration of follicles of the subepithelial tissue is not the only type of its regressive metamorphosis. Sometimes, undergoing cellular necrosis, follicles empty their contents outward after the epithelium covering them is shed (see figure). The process of follicle disintegration is very early accompanied by the formation of new connective tissue, appearing in the area of the follicle usually in connection with the adventitia of the vessels. Around the follicle and inside it, the formation of fibroblasts occurs, which then determines the replacement of the follicle with scar tissue. The same regressive changes occur in the area of inflammatory infiltration at a certain period of trachoma. As a final result, scar tissue forms in the place of trachomatous infiltration and follicles, the degree of development of which depends on the extent of the process. In addition to the general characterization of trachoma from the path-anatomical side, it is necessary to point out the changes in the epithelium of the conjunctiva. Already in the early stages of development of inflammatory infiltration, the epithelium, especially covering the follicles, is rarely normal. Usually the epithelial covering thickens, giving tongue-like ingrowths into the underlying tissue. In the regressive, especially scar period, the process of cornification of the epithelium—flattening of cells and their keratinization—occurs. In the clinical picture of trachoma, the growth of papillae is usual. Path-anatomical papillae, especially strongly developed on the convex edge of the cartilage, represent elevations of the conjunctiva not only in places of the pre-existing system of depressions and elevations in its normal state, but also where the normal conjunctiva has a smooth evenly arranged epithelium. Various and deep changes often arise in the cartilage itself, similar in nature to changes in the mucosa itself. Inflammatory infiltration sometimes involves the deep parts of the cartilage, but the formation of typical follicles is rarely observed. The Meibomian glands of the cartilage undergo a series of degenerative changes leading to their death. Often, early hyalinization of the cartilage tissue is noted in the cartilage, and sometimes its fatty degeneration is also observed. The outcome of the cartilage lesion can be its scar shrinkage—atrophy. Sometimes, undergoing a widespread process of degeneration, the cartilage becomes very thick, bumpy. Changes in the conjunctiva of the eyeball have been the subject of recent research. Contrary to clinical observations, histological studies of a number of authors (Pokrovsky, Eleonskaya, etc.) clearly indicate that the conjunctiva of the sclera is also often involved in the process. The nature of changes in the conjunctiva of the sclera is generally defined as chronic proliferative inflammation of the same type as in the conjunctiva of the eyelids. It should also be mentioned the changes in the tear-secreting and tear-conducting organs. Diffuse inflammation in the area of the lacrimal gland with infiltration of plasma cells has been described. In the late stages of trachoma, scarring occurs in the area of the lacrimal gland with cystic expansion of individual parts of it. Purely trachomatous lesions of the lacrimal sac, contrary to the indications of Kunt, cannot yet be considered proven. Thus, from all available data, it must be recognized that what is characteristic of the trachomatous process are not its histological components taken separately, such as the follicle or diffuse infiltration, but the combination of anatomical changes and their favorite localization. Difficulties arise in evaluating the histological picture of the initial forms of trachoma, when from the path-anatomical side there is not yet material that would allow to definitely differentiate trachoma at this stage of the process from follicular conjunctivitis. The histological picture of trachoma is not yet clearly defined enough and is one of the reasons for the existing disagreement in understanding its essence. Clinic. The clinical picture of trachoma is extremely diverse both in the extent of the process and in the degree of development of follicles and infiltration, the degree of hypertrophy of papillae, and in the nature of complications encountered. The course of this disease is chronic in the vast majority of cases, lasting for years, sometimes decades, and usually both eyes are affected. After an incubation period of 7-14 days, three main stages can be distinguished in the clinical course of the process, as Rahlmann proposed to do long ago. 1st stage—trachoma I stage progressive. It is characterized by the progressive development of inflammatory phenomena—redness, thickening due to infiltration of the conjunctiva, the appearance of grains-follicles, growth of papillae from the very earliest signs of the process up to the picture of florid trachoma.

(trachoma incipiens, recens, florescens). 2nd stage - trachoma II - regressive stage, when phenomena of follicular degeneration are observed, their disintegration, degeneration of inflammatory tissue and the beginning of the reparative scar process - the appearance of individual scars; the widespread degenerative process in this stage is especially typical in the picture of the so-called gelatinous trachoma (sulziges Trachom of German authors). 3rd stage - trachoma III - final stage, when scarring processes predominate, replacing the inflammatory infiltration with follicles. Developing according to such a scheme, the trachomatous process differs in enormous diversity of its clinical picture. A common phenomenon in T. of long duration is the mixing of different stages at the same time. T. begins in the vast majority of cases unnoticeably and the disease is often detected upon accidental examination, when it has already gone far or even completely ended. It is especially necessary to emphasize that T. in childhood proceeds unnoticed. This happens not only because the disorders of the eye condition caused by it are not noted by patients due to their age, but also because the trachomatous process in childhood often occurs in not such a severe form as in adults. Among children, cases of spontaneous healing of the process without particularly severe scar changes in the conjunctiva of the eye undoubtedly occur much more frequently. In its typical forms, T. begins with hyperemia, swelling of the transitional folds of the conjunctiva, with the appearance of follicles there, especially noticeable in the transitional fold of the upper eyelid. The trachomatous process in the transitional folds, however, does not linger long and soon crosses the boundary that lies between the transitional fold and the upper edge of the cartilage, spreading to the area of the cartilaginous conjunctiva. The cartilaginous conjunctiva of the upper eyelid swells, thickens, and on the hyperemic, thickened conjunctiva, follicles appear in the form of small whitish, grayish spots, visible from the depth of the tissue and sometimes rising above its surface. The spread of infiltration and follicles to the tarsal part of the conjunctiva makes the picture of the trachomatous process undeniable. With the progression of the process, the follicles developing in the transitional folds and in the area of the upper edge of the cartilage increase more and more in number. Due to diffuse infiltration and the development of a large number of follicles, the transitional fold, especially the upper one, when the eyelids are everted, protrudes from the palpebral fissure in the form of folded, bumpy ridges, dotted with grains of various sizes. The foldability of the conjunctiva with follicles sitting in the tissue sometimes reaches such a degree that a cockscomb-like appearance is obtained, and the follicles themselves, when abundantly erupted, resemble frogspawn in appearance. In addition to the transitional folds and cartilage, the semilunar fold of the conjunctiva is also very often affected - it appears thickened, lined with usually large follicles protruding above the surface of the fold. In developed forms of T., further spread of T. to the conjunctiva of the eyeball occurs. Sometimes very early on, hyperemia, thickening of the conjunctiva of the eyeball near the transitional fold, especially of the upper eyelid, can be observed, with the appearance of large, semi-translucent follicles there. Along with the development of thickening of the conjunctiva and follicles, almost a constant symptom of T. is the proliferation of papillae. The velvet-like texture and often rough irregularities, due to papillary hypertrophy, are observed in developed forms of T. in the area of the cartilaginous conjunctiva and transitional folds. Papillary hypertrophy sometimes dominates the entire picture of trachomatous changes, overshadowing the basic elements of the process - infiltration of the conjunctiva and follicles. The different state of the trachomatous conjunctiva in the progressive period allows some (Stellwag, Fuchs) to divide T. into separate forms: T. with predominant development of follicles they call granular T. (t. granulosum), T. in the presence of noticeable papillary proliferations - papillary T. (t. papillare), and cases in which both follicles and papillary growths are observed are considered as a mixed form (t. papillo-granulosum).-T. of the first period in some cases proceeds without any noticeable discharge from the conjunctiva (some call such cases t. sicca - dry T.), but in many cases it is accompanied by the appearance of secretion - purulent or mucopurulent. The abundance of secretion usually characterizes more rapidly progressing forms of T. and at the same time more contagious forms, since with a significant amount of discharge, more favorable conditions for its transmission are created. After a more or less long existence of the first period of T., symptoms of the 2nd period appear in the conjunctiva - phenomena of degeneration of inflammatory infiltration and follicles, their disintegration and replacement by scar connective tissue. Clinically, this is expressed in developed forms of T. by the fact that follicles and surrounding tissue become loosened, the follicles change in color - their color becomes dull-gray, grayish-yellow, they become indistinct in outline; they are larger in size and more numerous. In this period, it is often seen how follicles merge with each other; this is especially noticeable in the transitional folds and in the area of the upper edge of the eyelid cartilage, where the gelatinous degeneration of the conjunctiva, so characteristic of this period of T., also particularly clearly manifests itself. By the gelatinous form of T. is meant such a state of the conjunctiva when follicles, developing in particularly large numbers and reaching a large size, merge, degenerating, into one continuous gelatinous mass. The inflammatory infiltration is also subjected to this process, so that the entire conjunctiva of the transitional fold and cartilage, especially in its upper part, takes on a glassy, gelatinous character.-The clinical picture of the third period also differs in diversity. Along with scars, phenomena of inflammatory infiltration, formation of follicles, etc. are also observed. Only in late periods, occurring in individual cases after varying times, do we have widespread scar changes that sometimes involve the entire conjunctiva of the eyelids. Such a state of complete scar degeneration of the conjunctiva without the presence of infiltrate can be called the fourth period of trachoma (McCallan, Chirkovsky and others). The scar changes in the transitional folds are manifested in the so-called smoothing of them, reduction of their foldability. The changes are more noticeable in the area of the cartilage. Here, in mild cases, individual thin, network-like arranged whitish strips of scar tissue are visible, in severe cases the scars are coarse. With progressive shrinkage, the conjunctiva of the cartilage shortens considerably, contracts onto the area of the tarsal conjunctiva and the transitional conjunctiva; this sharply narrows the entire area of the conjunctival sac. In mild cases, only single barely noticeable scars, often visible only under a magnifying glass, testify to the past process. Due to the strong shrinkage of the tarsal conjunctiva and due to regressive changes in the cartilage itself, a very characteristic feature of the scar period of T. - a trough-like curvature of the cartilage, a change in the configuration of the eyelid - occurs. With severe scar shrinkage of the conjunctiva, the so-called symblepharon post. develops (see Conjunctiva). With further shrinkage of the eyelid conjunctiva, the curvature of the cartilage leads to one of the severe consequences of scar trachoma - entropion of the eyelid, improper growth of eyelashes (trichiasis). In the outcome of the trachomatous process in its severe forms, along with widespread scarring of the conjunctiva, the development of xerosis or xerophthalmia (see) is sometimes also observed. Acute T. In addition to the typical form of T. with its chronic course, an acute form of T. is also rarely encountered. The existence of such a form is disputed by some (Morax, Petit, McCallan), but, judging by the available data, it can be stated that in rare cases T. can arise acutely, manifesting in symptoms very similar to acute infectious conjunctivitis. According to Saemisch and Oguchi, such a form constitutes 6% of all trachomatous cases. The initial symptoms of acute catarrh in such a form of T. are soon replaced by signs of a follicular process. Among the edematous and hyperemic tissue, individual follicles begin to show through, and in the area not only of the transitional folds but also of the tarsal conjunctiva, papillary proliferations appear. At the same time, the signs of the acute process gradually weaken, the hyperemia of the conjunctiva decreases, the discharge decreases. The process usually transitions into the picture of typical, chronic T.-Unilateral T. As a deviation from the usual course, unilateral T. of long duration is sometimes encountered. This phenomenon undoubtedly occurs rarely. There are only hypotheses to explain unilateral T. They most often come down to the assumption of greater predisposition of one eye to trachomatous infection compared to the other or to the presence of immunity of one eye to T. Complications. Trachoma is characterized by various complications.

They give this infection an extremely severe character and are the cause of prolonged, sometimes multi-year visual disturbances and in a number of cases lead to the terrible outcome of T.—blindness. A very characteristic feature of the complete picture of T. is the involvement of the cornea in the form of pannus (see). The occurrence of this unique inflammation of the cornea, sometimes observed even in the early stages of T., makes the diagnosis of T. particularly reliable. Among other complications of the cornea, one should note the ulcers of the cornea that often occur during the trachomatous process, usually in the form of a deep, rapidly progressing infiltrate with the formation of an ulcer that often has a tendency to destroy the cornea throughout its entire thickness (see Keratitis). Furthermore, changes in the configuration of the cornea—its partial or complete protrusion—are observed, although rarely. The latter is usually in the form of keratoglobus (see Staphyloma). Acute contagious conjunctivitis is often a complication of the trachomatous process. Most often, it is a superimposed infection of the conjunctiva with Koch-Wicks bacillus, pneumococcus, or gonococcus. Sometimes, chronic infections, such as diplobacillary (Diplobac. Morax-Axenfeld) conjunctivitis, also join T., complicating its course. Infectious conjunctivitis can be a precursor to T., creating favorable conditions for the introduction of the trachomatous virus. When superimposed on T., these complications aggravate the latter, especially posing a danger of corneal involvement in the form of purulent keratitis. Further, it should be mentioned that in T., diseases of the lacrimal passages, especially the lacrimal sac, are sometimes observed. The presence of dacryocystitis (see) of any origin is a factor that complicates the course of T. Impairment of lacrimal drainage, and especially the pus with a huge number of microbes that accumulates in the lacrimal sac during dacryocystitis, by itself causes persistent chronic conjunctivitis and naturally has an adverse effect on the course of T. Rare is the involvement of the lacrimal canals in trachoma; it is attributed to a specific origin due to the spread of the trachomatous process to the mucous membrane of the canals (Rubert). The diagnosis of T. presents difficulties at the beginning of the process, when there is not yet a picture of the full development of all symptoms of the disease, when the process is limited to the involvement of only the transitional folds. The diagnosis is based not only on the presence of follicles but also on the presence of infiltration of the conjunctival tissue, clinically expressed in its thickening. The localization of the process—involvement in the process, in addition to the transitional folds, also of the conjunctiva of the upper eyelid cartilage—is extremely important for the diagnosis of T. As early as the 1880s, Prof. E. V. Adamyuk pointed this out. When the process is limited to only the transitional folds, the diagnosis of T. can only be made with their pronounced infiltration and the presence of many follicles. One must remember that the transitional folds are the initial site of localization of the infection, but they do not remain the only site of involvement for long. The process, in its spontaneous development, almost always spreads to the tarsal conjunctiva and other parts of it. At this time, the diagnosis is not difficult. However, when making the diagnosis of the initial form of T., mainly based on this, one must take into account the difficulties that arise when the follicles are located in the transitional folds or partially involve the conjunctiva of the cartilage, but are not accompanied by sharply expressed deep infiltration of the tissue. Such cases give particular cause for differential diagnosis with follicular catarrh and usually do not allow for an immediate diagnosis. For the diagnosis, observation is required, and in such cases, it is better to limit oneself to a presumptive diagnosis (trachoma in suspecto, dubium). Observation, sometimes even for a short time, allows one to be convinced of the development of either a typical picture of T. or, conversely, a benign follicular process. In recent years, Bonnet, Schousboe, and others have drawn attention to early changes in the limbus of the cornea in the initial periods of T., considering them an important diagnostic sign. These changes are visible under a binocular loupe and especially with a slit lamp. Prevention of trachoma as a socio-domestic disease must first go along the path of improving the economic and social conditions of the environment, i.e., along the path of further socialist construction. The enormous shifts in the social economy taking place in the USSR give every reason to believe that in the conditions of this successful construction lie the elimination of the century-old obstacles that stood in the way of the proper organization of prevention and the fight against T. in prerevolutionary Russia. One of the main basic parts of the dispensary method in the fight against T. is the accounting of morbidity from this infection, the identification of foci of the disease, and the study and improvement of the general sanitary and specifically socio-domestic features of the life of workers and collective farm masses. In accounting for T., until recently, a major obstacle was the absence of a unified accounting card for T., which was reflected in the different form and content of the existing accounting cards, and therefore, research conducted using various cards gave low-value results. The introduction of a unified accounting card by the People's Commissariat of Health of the RSFSR, built on a dualistic understanding of T., eliminates the inconsistency in the collection of information about T. Special attention during any kind of examination is directed to identifying the socio-domestic conditions of the environment that affect the spread of T., to establishing the sources and mode of infection.—The main organizational form in the fight against T. until now has been rural eye hospitals and hospital departments in cities. The direction of their activity toward the dispensarization of eye care in recent years has been indicated by a series of legislative enactments and instructions of the People's Commissariat of Health of the RSFSR. By a special resolution of the VTsIK and SNK of the RSFSR of November 28, 1927, general directives were given for the fight against T. as a socio-domestic disease. The most important measure provided for in this resolution of the VTsIK and SNK was the decreeing of the right for compulsory examination of persons regarding whom there is reason to suppose that they suffer from T., as well as the right for compulsory treatment of certain categories of the population (students of the first and second levels, organized childhood, students of higher educational institutions living in dormitories, etc.), regarding whom a fact of T. in its contagious period has been established, if these persons refuse voluntary examination and treatment. Subsequent instructions of the People's Commissariat of Health—15/III 1928 and 23/VII 1929—clarified in detail the plan for the fight against trachoma, but the resolution of the board of the People's Commissariat of Health of the RSFSR of 27/IV 1932 on the elimination of trachoma in the RSFSR in the second five-year plan is of particularly important significance. Anti-trachomatous measures have taken on an especially broad scale in recent years in such national republics and regions as the Chuvash ASSR, Mari, and Udmurt regions, with the Chuvash ASSR undoubtedly occupying first place in this regard. National republics, former 'inorodcheskie' (alien) districts that led a miserable existence in the era of the oppression of tsarist autocracy and feudal landlord exploitation, were grandiose foci of T. In the prerevolutionary period, in the 'inorodcheskie' districts of the former Kazan and Vyatka provinces, inhabited by Chuvash, Cheremis (Mari), Votyaks (Udmurts), and other national minorities, enormous prevalence of T. was observed. Thus, during mass examinations in 1913, among the Chuvash of the former Kazan province, T. was found in 50-70% of the entire Chuvash population in some places, and among the Votyaks, according to the data of eye teams, the percentage of trachomatous individuals reached 72-80, etc. At present, in the national republics and regions, with the enormous socio-cultural shifts in the life of the population, a consistent and very successful fight against T. is being carried out, which has already given exceptional results. It was mentioned above that in the Chuvash ASSR, a decrease in T. is noted year after year, the same is the case in the Mari region, Udmurt region, and other regions and republics previously severely affected by T.—In the Chuvash republic, mass dispensarization of the trachomatous population is being successfully developed. The so-called 'nest treatment' of T., consisting in the organization of trachomatous points within the medical districts, headed by a trachomatous sister, working under the supervision of doctors, is carried out with great consistency. At present, in the Chuvash republic with its million population, there are over 300 such points, and in the near future their number will be increased to 700. The fight against T. is being developed on approximately the same plan in other national republics, and there is every reason to believe that the task set by the health authorities to eliminate T. as a mass disease in these areas will be successfully resolved in the near future. The treatment of trachoma belongs to difficult tasks due to the persistence of the process and the lack of specific means against it. To this day, drug therapy in the form of the use of copper preparations (Cuprum sulfuricum), which has existed for a century, is the most widespread.

Many apply at present the treatment with chaulmoogra oil (01. chaulmoograe) in the form of rubbing it into the conjunctiva every 2-3 days (Delanoe). Chaulmoogra oil is indicated in various stages of T., where there are phenomena of infiltration of the follicles. The best results from it are obtained when combined with expression of the follicles. Cyanide of mercury is also applied with success, most often in the form of compresses and drops (in a solution of 1:3,000-1:5,000), and in some cases, the performance of subconjunctival injections of cyanide of mercury proves useful. Mechanical methods occupy a notable place in the treatment of T., most often in the form of medicinal massage (with solutions of sublimate, cyanide of mercury, irol, etc.). The methods of surgical treatment of T. are diverse. They are indicated especially in the first and second periods. The common and most effective method is the expression of the follicles (expressio folliculorum). Expression is performed with special forceps. The forceps of Bellarminov, Donberg, and Knapp are widely used. Expression is repeated at intervals depending on the severity of the process, and along with expression, various types of medicinal therapy are carried out. Recently V. P. Filatov proposed to perform repeated expression systematically, without conducting the usual intermediate treatment. French authors (Cuenod et Nataf) recommend the so-called xysis, which consists in scraping the surface of the conjunctiva with a special curette after anesthesia, with destruction of the follicles and adenoid tissue, followed by an injection of cyanide of mercury into the tissue. Of purely surgical methods, the most commonly used are the operations developed by Kunt: simple excision of the plica semilunaris, combined excision of the plica semilunaris and cartilage, and extirpation of the cartilage. The first two operations are indicated in the progressive stages of T., the last in the cicatricial stage. A modification of the combined excision is the operation of Pick, in which only part of the cartilage is removed, but the plicae semilunares are preserved. In addition to the mentioned methods of treatment, in some cases physiotherapy in the form of deep cauterizations of the conjunctiva of the plicae semilunares by Abadie is successfully applied. In recent times, the application of diathermy or diathermocoagulation (Worms, Bidault, etc.) has attracted attention, which sometimes have a pronounced and rapid effect. The application of radium (Kohn, Zelenkovsky, etc.) aroused much hope at one time. It is usually useful in combination with other methods of treatment. Radiotherapy of T. (Merkulov, Bykhovsky, Gasul and Neminsky and many others) is gaining relatively wide popularity in our Union, but there are as yet no definite data to assert that this type of therapy gives lasting results, especially in severe forms of T. It, like radium, is a good auxiliary means in combination with other types of therapy. In addition to local therapy, which does not have a specific character, attempts at specific treatment of T. continue to this day. They have not yet given definite favorable data. Neither vaccinotherapy nor serotherapy, with local as well as general application, are accompanied in most cases by a noticeable effect. Heterospecific therapy, most often in the form of guttohemotherapy, gives good results in some cases, especially when there are complications from the side of the cornea. In the treatment of T., one must not neglect care for the general condition of the patients, since clinical experience teaches that T. runs especially severely in patients burdened with general diseases, such as t.b.c., resp. scrofula, syphilis, etc. Therapy aimed at increasing the general resistance of the body is quite indicated also in T. Undoubtedly favorable influence is exerted on the course of trachoma by the stay of patients in favorable climatic conditions. The beneficial effect of mountainous coastal regions with their dust-free air and ozonized atmosphere has been pointed out since ancient times.

V. Chirkovsky.

TREVIRANUS Gottfried Reinhold (Gottfried Reinhold Treviranus; 1776-1837), German biologist, who summarized the knowledge and ideas of his time about the phenomena and laws of organic life in his works: "Biologie Oder Philosophie der lebenden Natur, fur Naturforscher und Arzte" (Vol. I-VI, Gottingen, 1802-22) and "Erscheinungen und Gesetze des organischen Lebens" (Vol. I-II, Bremen, 1831-33). His natural philosophy represents a mixture of vitalistic ideas about the always existing on earth "vital plastic force", the ideas of Leibniz and Fichte about the unity of the organization of an individual organism and the organization of the world with phylogenetic thoughts about the primary origin from the inorganic world of primary organic forms (under the action of the vital force) and the gradual development from them in different directions of higher organisms. T. represented the system of organisms in the form of a tree with leaves of common origin. Each species, in T.'s opinion, has a period of growth, prosperity, and decline, transforming into other higher forms, and fossils are the remains of the stages of life passed through.