Yaws

YAWS, framboesia (from French framboise - raspberry), yaws (Antilles), Iosa disease, polypapillomatropicum (Charlouis), pian (French colonies), bubas (in Brazil), tonga, a chronic infectious disease of the skin, clinically characterized by papillomatous raspberry-like growths, tumor-like masses, and ulcerative lesions of the skin and bones. Yaws occurs endemically in a number of tropical countries and regions (West Indies, Ceylon, South America, Madagascar, Australia, Asia). In its nature and clinical course, yaws shows a certain similarity to syphilis, which gave some authors grounds to consider yaws a variant of syphilis rather than an independent nosological form. However, the current state of the question regarding yaws shows that it is an independent disease. The causative agent of yaws is Spirochaeta pertenuis, s. pallidula, discovered in 1905 by Castellani, which has the appearance of a spiral, making it similar to the pale spirochete of syphilis; the research methods are also identical, however, experimental infection of monkeys and rabbits with Spirochaeta pallidula has not been successful. The entry gates for infection are excoriations or ulcers, and flies are considered the transmitters of yaws. Children with eczema under the age of 10 are most susceptible to this infection. Clinical course of yaws. In its course, yaws can be divided into 3 stages. The prodromal or incubation stage, especially noticeable in children, lasts from several days to several weeks and is characterized by the development of primary lesions (mother yaws), i.e., the mother plaque, and various general disorders: fever, headaches, bone and joint pains, and digestive disorders. Initial changes may appear in the form of papular, nodular, or pustular eruptions, accompanied by more or less pronounced itching. The disease can occur on any area of the skin, but most often it localizes on the upper and lower limbs, hands, and face; in nursing women - on the mammary glands, in infants - usually in the corners of the mouth. After 1-3 months, the secondary stage develops, characterized by the appearance of small papules bordered by a wide red halo, with a yellow dot in the center, which increase in number and size and last for several weeks or months, turning into gumma-like tumors - often subject to ulceration and deep tissue destruction (the third stage). The nodular formations of the secondary period are round or conical in shape, often with a central umbilical depression covered with a honey-yellow crust. With reverse development, some of them leave white or pigment atrophic spots; others mostly persist for several weeks or months, showing a tendency to papillomatous growths and forming in the further course raspberry-like, somewhat constricted at the base nodular granulomas. The latter sometimes reach large sizes due to the fusion of neighboring tumors and secrete a repulsive foul-smelling secretion. Sometimes circular plaques of various sizes develop, which can also ulcerate or resemble ringworm trichophytia disks (ringworm yaws) in appearance. The duration of the secondary period varies. Along with the spontaneous disappearance of old plaques and tumors, there is a permanent development of new numerous nodular formations for a whole series of months, but as a rule not exceeding 3-6 months in children and 6-18 months in adults (Sutton). The so-called tertiary period is distinguished by the formation of ulcerogummatous lesions of the bones and severe destructive changes that simulate tertiary syphilis. In general, tertiary phenomena in yaws are observed very rarely. According to Kynsey, who worked for many years in Ceylon, tertiary changes in yaws are an accidental phenomenon. They include nasal exostoses called goundou, the disfiguring rhinopharyngitis of Leys, called rhinopharyngitis gangosa. Lesions of internal organs in yaws are unknown. Pernet and others believe that the specific yaws manifestations largely depend on secondary pyogenic infection with staphylococci and other microbes. The results of histological research (Mac Leod) of various stages of yaws show great similarity with syphilis. Hunt and Johnson found some changes in the blood; the number of red blood cells is below normal, the number of white blood cells is higher; a sharp increase in the number of large mononuclear cells; eosinophilia occurs less frequently. After a single bout of the disease, immunity to re-infection is usually acquired, although there are cases when the same person was affected by yaws a second time. Levaditi and Nattan-Larrier claimed that monkeys inoculated with syphilis were immune to yaws. On the other hand, monkeys affected by yaws can be infected with syphilis (Stitt). The differential diagnosis of yaws should be made mainly with syphilis. However, the following points speak against syphilis: yaws most often occurs in childhood and rarely after the age of 35; the localization of the primary ulcer is usually extragenital, the phenomena of accompanying adenitis are inconsistent; unlike the polymorphism of rashes in syphilis, those in yaws are always the same, accompanied by itching and do not leave scars. While syphilis is transmitted congenitally, such transmission of yaws is unknown. A difficulty for differential diagnosis may be the presence of a positive Bordet-Wasserman reaction in patients with yaws, as well as in patients with syphilis; this circumstance can be used for the differential diagnosis of yaws with other tropical skin diseases. Prognosis. The average duration of the disease is 6-12 months. With appropriate rational treatment, it can be shortened. The general condition of the patient is not significantly affected by the course of the disease, except for the initial febrile stage. In general, yaws rarely threatens life. Treatment. The most active therapeutic effect is possessed by salvarsan preparations; sometimes a single injection of neosalvarsan is sufficient; this method of treatment made it possible to close within a month a large hospital in Batavia for patients with yaws. Along with intravenous administration of neosalvarsan, stovarsol (12 tablets of 0.5 each for three days) is recommended (Darier). Matsunaga recommends injections of bismuth in the first and second stages.