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Query: UMLS:C0019621 (Langerhans cell histiocytosis)
 3,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Skin biopsies and a lymphnode of three children with infantile Histiocytosis-X (Letter-Siwe Disease) were studied with enzymehistochemical and sheep-erythrocyte rosetting techniques. The majority of cells making up the infiltrates of skin and lymphnode showed rather weak acid phosphatase and nonspecific esterase activity but considerable leucyl-beta-naphtylamidase activity. Sheep-erythrocyte rosetting techniques performed on frozen sections indicated the presence of receptors for the Fc fragment of IgG, but no receptors for C3 could be demonstrated. Cells with the same enzymehistochemical characteristics could be found in thymus-dependent areas of normal spleen, of normal and reactive lymphnodes and in thymic medulla but not in B-cell areas or thymic cortex. It is suggested that Histiocytosis-X cells belong to the Mononuclear Phagocyte System and that they are related to or identical with cells normally present in the thymus dependent areas of the lymphoid tissue involved with the functioning of cell-mediated immunity.
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PMID:Infantile histiocytosis X. 15 Mar 6

1. Langerhans cells represent specific granula-containing dendritic cells which do not have desmosomes, tonofilaments and (pre)melanosomes and which therefore appear as clear cells in the epithelial tissue. 2. They occur in the squamous epithelium, and also in the corium, lymph node and thymus. They account for 1-1,7% of the whole volumen of the epidermis. 3. They do not represent effete melanocytes, but they originate from the mesenchym. Their migration from the dermis into the epidermis, their identity with histiocytosis X cells, their surface receptors as well as function underline the mesenchymal origin. 4. Probably the Langerhans cells regulate the mitosis and differentiation of the keratinocytes. 5. The antigen-presenting and lymphocyte stimulating functions of Langerhans cells as effector cells in allergic contact eczema are proved. They are able to phagocytize antigens (haptens), to apposite lymphozytes, to proliferate after the challenge by antigens as well as to migrate through the lymph vessels into the regional lymph nodes. 6. At their surface they bear receptors for Fc-IgG and C3 as well as Ia-antigens as immune response genes of the major histocompatibility complex (MHC). 7. With regard to point 5 and 6 they have the same properties as the macrophages. 8. Langerhans cells are damaged and destroyed, respectively, by immune complexes after activation of the complement pathway as well as by killer T-lymphocytes. Thus they are regulated as target cells by humoral and cellular mechanisms. 9. The allergic inflammatory reaction is triggered by mediator substances (of lysosomal origin?) which are liberated by the destruction of the Langerhans cells as well as by lymphokines. The preferently suprabasal occurrence of the Langerhans cells explains the early beginning of the edema and spongiosis as well as their localization in the lower layers of the epidermis. 10. The macrophages-analogous and antigen-presenting functions, which are genetically regulated are essential for the sensitization in allergic contact eczema. The ability to stimulate allogenic T-Lymphocytes in the mixed lymphocyte reaction might be of particular importance for the skin transplantation.
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PMID:[The Langerhans cell--its macrophages-analogous function in the triggering of the allergic contact eczema (author's transl)]. 15 6

Monozygotic twin boys presented at 1 year of age with seborrheic skin rash, otorrhea, and hepatosplenomegaly. Skin biopsy confirmed Langerhans cell histiocytosis. Treatment with conventional antineoplastic drugs and with calf thymus extract was ineffective. The disease remained refractory to recombinant human alpha-interferon and to low-dose total body irradiation, and the children died between 3 and 3 1/2 years of age.
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PMID:Disseminated Langerhans cell histiocytosis in identical twins unresponsive to recombinant human alpha-interferon and total body irradiation. 151 Jan 99

Histiocytosis X (HX) is characterized morphologically by a proliferation of Langerhans' cells (LC), and most often has an indolent, chronic course. To determine whether a distinct clinicopathologic entity of malignant histiocytosis X exists, the authors examined tissues from 31 patients with HX and divided them into four categories. Group A (19 patients) was characterized morphologically by benign-appearing LC and had an indolent course. The male:female (M:F) ratio was 10:9, and the mean age was 21 years (range, 2 months to 60 years). The immunophenotype of this group was S-100+, vimentin+, LN-2+, LN-3+, lysozyme-, LCA-, Leu-M1-. Group B (three patients) had benign-appearing LC, yet had an aggressive clinical course. All patients were male, with a mean age of 47 years (range, 3 years to 72 years). Organs involved included the liver, spleen, heart, thymus, lung, kidney, and pancreas. The immunophenotype was the same as for Group A. Group C (two patients) had atypical and malignant appearing LC, yet a relatively benign clinical course. The ages were four and 65 years, with one female and one male patient. In both patients, the cells were S-100+, vimentin+, LN-2+, LN-3+, and LCA-. Group D (seven patients) was characterized by atypical and malignant-appearing LC and an aggressive clinical course. The mean age was 25 years (range, congenital to 54 years) with one female and six male patients. Organs involved were the thymus, lungs, spleen, liver, kidney, brain, heart, pancreas, stomach, and muscle. Birbeck granules were found in two patients, and the one patient on which fresh tissue was available was CD1+. The typical immunophenotype was S-100+, vimentin+, LN-2+, LN-3+, Leu-M1-, lysozyme-. The results of our study indicate that (1) a distinct clinical entity of malignant HX, characterized morphologically by malignant-appearing LC and clinically by male predominance, atypical organ involvement, and an aggressive clinical course, does exist; and (2) the morphologic appearance of the LC is an imperfect predictor of the clinical severity of HX.
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PMID:Malignant histiocytosis X. A distinct clinicopathologic entity. 191 75

This is a report on 2 adult patients suffering from pulmonary histiocytosis X. The aetiology and the diagnostic and therapeutic approach are discussed on the basis of a review of the literature. This is a rare disease that is triggered by a virus and immunologically conditioned, the disposition being genetically transferred. It is characterised by cells known as histiocytosis X cells with typical X bodies and immunocytochemically identifiable S 100 antigen. It will usually be necessary to perform an open biopsy of the lung to determine the histology of histiocytosis X. Roentgenologically pathognomonic signs are in particular ring-shaped structures of up to 5 mm diameter with a marginal edge. Lung function analysis revealing hypoxaemia after stress and, less significantly, diffusion capacity and vital capacity, are also among the most sensitive data pointing to histiocytosis X. Indication for treating the patients, who usually do not display prominent signs and symptoms, should be discrete because spontaneous remissions occur very frequently. If the patients display relevant signs and symptoms, corticosteroid long-term treatment over 12 months with 0.5-1.0 mg/kg body weight per day is recommended employing a slowly and progressively reduced dosage schedule. Chemotherapeutic drugs or thymus extracts are administered in a few rare instances.
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PMID:[Pulmonary histiocytosis X]. 194 59

Collections of large cells and smaller satellite-like cells arranged in an autonomic ganglion-like pattern and resembling the white matter lesions of tuberous sclerosis were found in the thymus, lungs, liver, appendix, and heart of an 8-month-old infant who exhibited other pathologic findings of tuberous sclerosis (rhabdomyomas of the heart and multiple kidney cysts). Focal cytoplasmic staining for S-100 and GFAP was noted in some large cells, suggesting neural (probably schwannian) differentiation. Dysplastic neurogenic foci appearing in internal organs may represent another morphologic marker of tuberous sclerosis. The simultaneous presence of Langerhans cell histiocytosis produced an unusual combination not previously reported.
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PMID:Multivisceral dysplastic lesions in a patient with tuberous sclerosis and Langerhans cell histiocytosis. 219 48

Human epidermal Langerhans cells express two (CD1a and CD1c) of the three human thymic cell surface differentiation antigens (CD1a, CD1b, and CD1c). The first cluster of differentiation antigens (CD1) is defined by a group of monoclonal antibodies (MCA). All these MCA were obtained after immunization of mice or rats with human cortical thymocytes. OKT6 MCA (a CD1a MCA) was the first to be described as reactive with human epidermal Langerhans cells. We produced a murine MCA, called DMC1, after immunization with proliferating Langerhans cells of Eosinophilic Granuloma of the bone (Histiocytosis X). In tissues DMC1 MCA reacted with epidermal dendritic cells (Langerhans cells) in the skin and cortical thymocytes in the thymus as observed on indirect immunofluorescence. At the ultrastructural level, DMC1 MCA was specific for Birbeck granule-containing Langerhans cells and did not react with melanocyte and keratinocyte populations. The quantitative analysis of immunoelectron labeling and the cytofluorometric study showed that the intensity of labeling was inversely correlated with the concentration of trypsin used in the preparation of epidermal cell from skin samples. DMC1 MCA precipitated a protein with a relative mass of 49,000 (CD1a molecule) from lysates of iodinated epidermal Langerhans cells under reducing conditions. It recognized the original CD1a molecule (Mr 49,000) but not the membrane breakdown product of CD1a (Mr 27,000) brought about by trypsin.
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PMID:DMC1: a monoclonal antibody produced from histiocytosis X cells which reacts with the native CD1a molecule of human epidermal Langerhans cells. 246 37

Histiocytosis X (HX) is a rare disorder of histiocytic proliferation characterized by a broad spectrum of clinicopathologic disease. An unusual case of Letterer-Siwe disease (LSD) or subacute disseminated HX in a 71-year-old woman is presented. The patient had a 3-year history of splenomegaly before skin lesions developed. She presented to our clinic at 1.5 years later and the diagnosis of HX was made by skin biopsy. Topical nitrogen mustard (NM) therapy resulted in complete clearing of cutaneous lesions. Her condition was stable over the next 10 months. However, she subsequently suffered a rapid and fatal dissemination of her disease. Systemic treatment with prednisone, vinblastine sulphate, and suppressin A (SA) (a calf thymus derived hormone preparation that specifically induces suppressor T-cells) was ineffective. Characteristic histopathologic, immunohistochemical, and electron microscopic findings of HX are illustrated. A review of the adult cases of LSD and treatment options for HX are presented and discussed.
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PMID:Letterer-Siwe disease in adults. 264 29

The authors described a case of the syndrome of erythrophagocytic histiocytosis in an infant with primary immune deficiency who died at the age of 11 months and 20 days. Microscopic examination revealed focal and diffuse histiocyte proliferation in the bone marrow, lymph nodes, liver, and lung. Histiocytes were found to actively phagocytize erythrocytes and hemosiderin. The changes in the thymus were regarded as congenital primary unclassifiable immunodeficiency. The differential diagnosis of the syndrome was made in comparison with histiocytosis, histiocytosis X and familial erythrophagocytic lymphohistiocytosis.
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PMID:[Erythrophagocytic histiocytosis syndrome in a child with a primary immunodeficit]. 274 35

A case of a myasthenic patient with the association of unifocal histiocytosis X (eosinophilic granuloma) and lymphoid follicular hyperplasia of the thymus is presented. The combined diagnosis was made on histological grounds and supported by immunohistochemistry. Two aspects of this case are of interest: (1) it is the first reported case of the association of histiocytosis X and lymphoid follicular hyperplasia of the thymus in a myasthenic patient; and (2) the pathogenesis of this peculiar association does not seem to be fortuitous but rather might be related to the general derangement of the immune system present in myasthenia gravis.
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PMID:Histiocytosis X and lymphoid follicular hyperplasia of the thymus in myasthenia gravis. 278 37


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