Reticulo-Endotheliosis

RETICULO-ENDOTHELIOSIS, a term that became established in medicine after 1922–1923, after the first descriptions of peculiar diseases consisting of a widespread systemic proliferation of reticulo-endothelial cells. In the future, however, it turned out that the indicated changes of the reticulo-endothelial apparatus were known earlier (the case of Borisova in 1903, Pentmann in 1916), but due to vague information about the reticulo-endothelial system, they were described under other names and illuminated incorrectly. Since 1923, the term "reticulo-endotheliosis" began to imply a self-originating systemic proliferation of reticulo-endothelium, involving the lymph, glands, spleen, bone marrow, and liver, and sometimes other organs. The first quite clear cases of this kind were described by Goldschmidt and Isaac, Letterer, Schultz, Wermbter, and Puem, Chistovich and Bykova, Abrikosov and Wolf (1927). Over subsequent years, a very large number of similar cases have been published. With the accumulation of material on R. mentioned above, it turned out that the cases described under this name, both in morphological expression and in their essence, are far from identical. In general, if the term "reticulo-endotheliosis" is referred to all hyperplasias of reticulo-endothelium that systemically involve the lymph, glands, spleen, bone marrow, and liver, then all these R. must be divided into 4 groups (Epstein, Abrikosov and Wolf, etc.). 1. Reticulo-endothelioses arising from the absorption by reticulo-endothelial cells of various metabolic products. This group includes such diseases as Gaucher's disease, Niemann-Pick disease, Schüller-Christian disease, as well as xanthomatoses and lipidoses with hypercholesterolemia and lipemia. 2. Infectious-reactive or inflammatory-proliferative reticulo-endothelioses. Here we are dealing with a reactive granulomatous proliferation of reticulo-endothelium, which occurs in lymphogranulomatosis, mycosis fungoides, typhoid fever, etc. Lymphogranulomatosis deserves special attention in this regard, some forms of which are expressed not in granulomatous proliferation, but in diffuse hyperplasia of reticulo-endothelium. 3. Spontaneous, independent reticulo-endothelioses. This group, strictly speaking, alone deserves the name "reticulo-endotheliosis," since here we are dealing with a self-contained disease requiring a special designation. Clinically, this is accompanied by a severe, progressive anemia and progressive enlargement of the lymph, glands, spleen, and liver. Less often, one of these organs drops out of the disease. At autopsy, a picture (enlargement of lymph, glands, spleen, liver, red bone marrow) is found that makes one think of an aleukemic type of disease. The essence of the disease is usually clarified only after microscopic examination. Under the microscope, one finds the multiplication of either only reticular cells, or only sinus endothelium, or capillaries, or both elements simultaneously. This selectivity of the participation of certain cells in the process served as the reason for recognizing, alongside R.-e., pure "reticuloses" and "endothelioses." The proliferating elements of reticulo-endothelium displace the pre-existing tissue; however, destruction of tissue, penetration of the capsule in lymph, glands, and spleen, or sharp destruction of bone tissue from bone marrow is never observed. In some cases, however, the formation of metastatic nodules (in the lungs, kidneys, testicles) was noted, and sometimes true destructive tumor growth occurred. Cases of the latter type represent transitions to the fourth group of R.-e. (see below). The fact that a benign R.-e. can transition into malignant tumor growth can be evidenced by the recently published case of Ungar. In most cases of spontaneous R.-e., the blood, besides anemia, shows no changes. However, in a number of cases, there was a subleukemic or even leukemic increase of white forms, and in some cases the matter concerned an increase in the number of lymphocytes, while in the majority of such cases the increase of white forms concerned monocyte-type cells with certain signs of atypicality. Based on the above, it is customary to speak of aleukemic and leukemic forms of R.-e.; leukemic forms, by the blood picture, approach those leukemias which are sometimes called monocytic, splenocytic, and reticulo-endothelial leukemias. Regarding the pathogenetic essence of spontaneous R.-e., it must be said that in the first time there were many authoritative researchers (Lubarsch, Sternberg) who rejected R.-e. as an independent nosological unit. Sternberg categorically asserted that all cases described as R.-e. can be divided into two subgroups: in some of them the matter concerns sepsis accompanied by reactive proliferation of reticulo-endothelium, sometimes with a "leukemoid" change of blood, while the others simply relate to lymphogranulomatosis. Along with this, many authors, recognizing the independence of R.-e., placed them in the group of leukemias (leukoses) and considered them, alongside myeloid and lymph, leukemia and aleukemia, as a "third form" - reticulo-endothelial leukemia and aleukemia. At present, with the accumulation of a significant number of observations regarding R.-e., the former point of view of Sternberg is considered incorrect. If reactive hyperplasia of reticulo-endothelium of septic origin is sometimes observed and if some forms of lymphogranulomatosis are expressed in diffuse hyperplasia of reticulo-endothelium, it can still be considered proven that spontaneous aleukemic and leukemic R.-e. exist, essentially close to leukoses. 4. Blastomatous (tumor) R.-e. represent a proliferation of reticulo-endothelium that proceeds as a malignant tumor. It destroys tissue and gives true metastases. In the majority of these rare cases, the proliferation begins as a local malignant tumor of the liver, or spleen, or a group of lymph, glands; subsequently, the tumor can spread predominantly systemically through the lymph, glands. In rarer cases, the neoplasm from the very beginning has a multiple systemic character, affecting simultaneously many lymph, glands, spleen, and liver. Microscopically, the tumor can have an alveolar structure of endothelioma (reticulo-endothelioma); more often it is built on the type of sarcoma. For tumors of the latter type, Roulet recently proposed the name "Retothelsarkom" (from "retotelium", synonym reticular cells) - sarcoma of reticular cells. This type of tumors Roulet categorically separates from other sarcomas of lymph, glands (lymphosarcomas and ordinary sarcomas).