1/10. Evidence for a hybrid macrophage phenotype in erythrophagocytic histiocytosis.PURPOSE: The phenotype of the proliferating cells in two patients with erythrophagocytic histiocytosis is described. These 6- and 18-month-old female patients presented with fever, anemia, hepatosplenomegaly, and lymphadenopathy. MATERIALS AND methods: Clinical histories were reviewed, and pathological specimens of both patients were studied by histology, and electron microscopy/immunohistochemistry using antibodies against macrophage and Langerhans cell (LC) antigens. RESULTS: histology revealed prominent erythrophagocytosis of proliferating histiocytes. By immunohistochemistry, conventional macrophage (HAM-56, alpha 1-antitrypsin, alpha 1-antichymotrypsin, lisozyme, CD68, and alpha-subunit of S-100 protein) and LC (CD1a and S-100 protein) markers were positive, as well as double labeling for CD1a and alpha 1-antichymotrypsin, in a majority of proliferating cells. Ultrastructural examination revealed Birbeck granules and prominent phagolysosomes frequently in the same cell. CONCLUSIONS: The hybrid ultrastructural and immunohistochemical phenotype between phagocytic macrophage and LC of proliferating histiocytes supports the common origin of these different histiocyte subtypes. This unusual phenotype might be the expression of the proliferating (hybrid) precursor or be the effect of unknown stimuli. Additional cases of childhood erythrophagocytic histiocytosis should be studied with immunophenotyping and ultrastructure to determine whether the hybrid phenotype represents a specific entity or an epiphenomenon.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/10. Reactive angioendotheliomatosis or intravascular histiocytosis? An immunohistochemical and ultrastructural study in two cases of intravascular histiocytic cell proliferation.Two elderly women with complex medical histories presented with erythematous patches, in one case involving the face and forearms, and in the other both elbows. Punch biopsies from both patients revealed intravascular proliferations of medium-sized and large cells with luminal occlusion typical of angioendotheliomatosis. Immunostaining did not show either lymphocytic or endothelial cell antigens but was consistent with a histiocytic differentiation of the intravascular cells in both cases, and was further substantiated by ultrastructural examination in one case. One patient received a course of cyclophosphamide therapy over 15 days. skin lesions faded but did not disappear. The patient died 10 months later from cardiac and renal failure, which was most probably unrelated to the skin lesions. In the other case, lesions diminished but did not entirely resolve with treatment with low doses of oral prednisone. Angioendotheliomatosis can be divided into a malignant variant, which is an angiotropic lymphoma mostly of B-cell phenotype, and a benign, reactive variant, which is characterized by a proliferation of cells expressing endothelial cell markers. Only one case of angioendotheliomatosis with cells of histiocytic differentiation has been published previously under the name of intravascular histiocytosis. Our cases are very similar to the latter. The question arises as to whether intravascular histiocytic cell proliferation is a neoplastic proliferation of histiocytes or an early stage of classic reactive angioendotheliomatosis representing the residual cells associated with organization of microthrombi, which will be later followed by endothelial cell proliferation.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/10. Post-scabetic nodules: a lymphohistiocytic reaction rich in indeterminate cells.We studied six infants and two adult cases of nodular scabies with immunostains and electron microscopy. All eight cases have had either direct (KOH) or family histories of scabies and were treated with lindane 1% cream or permethrin 5% cream. family members responded very well, but our patients developed multiple papulo-nodular lesions which were initially very pruritic and, in some cases, persisted from several months to over one year. H & E stain of biopsied tissue sections revealed a heavy perivascular and periappendageal lymphohistiocytic cell infiltration. Immunophenotype of these cells was compatible with langerhans cells, i.e. CD1A ( ), S-100 ( ) and HLA-DR ( ). Electron microscopy showed that these histiocytic cells satisfied all the ultrastructural criteria of Langerhans cells except for the absence of Birbeck's granules. Lag, a monoclonal antibody for Birbeck's granules, was negative. "Persistent nodules in scabies" or "nodular scabies" seems to represent a prolonged response of indeterminate cells-lymphocytes to mite antigens.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/10. Lymphoplasmacytic lymphoma with monoclonal gammopathy-related pseudo-Gaucher cell infiltration in bone marrow and spleen--diagnostic and therapeutic dilemmas.Gaucher-like cells have occasionally been described in various haematological malignancies including Hodgkin's disease, non-Hodgkin's lymphoma, multiple myeloma (MM) and chronic myelogenous leukaemia (CML). A special type of this phenomenon is crystal-storing histocytosis or the so-called pseudo-pseudo Gaucher cells (PPGC) in which crystalline protein storage in macrophages is induced by paraproteinemia. Here we describe a 54-year-old man with an initial suspicion of gaucher disease and monoclonal IgA gammopathy in whom a correct diagnosis of lymphoplasmacytic lymphoma (LPL) with massive infiltration of bone marrow and spleen by PPGC was confirmed by immunological, ultrastructural and molecular characterisation. The activity of leukocyte beta-glucocerebrosidase was only slightly elevated (7.3 nmol/mg protein/1 h) which ruled out the diagnosis of classic Gaucher's disease. The patient received two courses of CHOP without improvement and anti-CD20 monoclonal antibody (rituximab) with only temporary stabilisation. Subsequently, he underwent splenectomy because of prolonged severe pancytopenia and a suspicion of hypersplenism. After splenectomy significant haematological improvement was observed. Following anti-CD20 therapy, changes in immunoprofile and morphology of tumour cells were evident. Before treatment the population of LPL was more divergent, with expression of LCA, CD20, CD38 and CD138. However, after the treatment, there were more mature plasma cells which no longer expressed CD20 antigen-this picture was more consistent with the diagnosis of plasma cell myeloma. Similarly, in the spleen there were no CD-20-positive cells evident. Finally, the patient received two courses of VAD vincristine, doxorubicin, dexamethasone) with further haematological improvement but complete response was not achieved.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
5/10. Isolated congenital histiocytosis in the palpebral conjunctiva in a newborn.PURPOSE: To report a rare case of congenital histiocytosis in a newborn without skin involvement. DESIGN: Interventional case-report. methods: A full-term baby presented with a mass over the palpebral conjunctiva of his left upper lid. Ophthalmic examination was otherwise normal, and the baby was healthy. There were no skin lesions. RESULTS: The lesion was completely removed surgically. Pathologic examination demonstrated a cellular infiltrate composed of eosinophils and histiocytes. immunohistochemistry disclosed positive stain for protein s-100 and CD1 antigenic determinant. Pediatric oncology evaluation was completely normal. Eighteen months after presentation, the patient remained healthy without recurrence of the lesion. CONCLUSIONS: Rare cases of congenital histiocytosis can present as a solitary lesion over the palpebral conjunctiva, without skin or systemic involvement.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/10. Regressing atypical histiocytosis. Aberrant prothymocyte differentiation, T-cell receptor gene rearrangements, and nodal involvement.Two cases of regressing atypical histiocytosis were studied. New findings reported include the presence of CD1 epitope on large atypical histiocytoid cells and apparent early lymph node involvement. Because regressing atypical histiocytosis may demonstrate aberrant thymic differentiation antigen expression and T-cell receptor gene rearrangements, initial lymph node involvement, and eventuation in conventional lymphoma in some cases, the alternative term regressing-phase anaplastic lymphoma is proposed as a more accurate designation for this entity.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/10. Regressing atypical histiocytosis and lymphomatoid papulosis: variants of the same disorder?We report a patient with lymphomatoid papulosis who developed a lesion with the clinicopathological features of regressing atypical histiocytosis. Immunohistochemical studies supported a T-cell histogenesis and many of the atypical cells demonstrated BerH2 (Ki-I antigen) positivity. The case supports the view that regressing atypical histiocytosis and lymphomatoid papulosis are different manifestations of the same disease spectrum.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
8/10. An unusual histiocytoid proliferation in infancy.A 2 1/2-month-old female infant was admitted to the Hopital Ste-Justine for investigation of marked hepatosplenomegaly. The pregnancy and neonatal period were uneventful and the child had exhibited normal growth. There were no skin or osseous lesions. Investigations revealed a coagulopathy with hypoproteinemia, but normal liver enzymes. An open liver biopsy revealed widespread infiltration of portal veins and hepatic sinusoids by large histiocyte-like cells, exhibiting protein s-100 and Ia antigen, but negative for OKT6, peanut agglutinin, and T and B cell and macrophage markers. Ultrastructural examination failed to reveal Birbeck granules. After a 4-month course of chemotherapy, liver and spleen size decreased, the biochemical profile returned to baseline levels, and the child has remained well. A repeat liver biopsy, performed at the end of the therapeutic trial, was normal. This patient presents an unusual pattern of infiltration of liver and spleen not readily classifiable within the present scheme of histiocytic disorders.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
9/10. A case of pleomorphic T-cell lymphoma with a high content of reactive histiocytes presented with hypereosinophilia.A case of peripheral T-cell lymphoma classified, according to the updated Kiel classification, as a large pleomorphic T-cell lymphoma with a high content of reactive histiocytes and blood hypereosinophilia is reported. light microscopic examination revealed a diffuse effacement of the lymph node structure by large pleomorphic lymphoma cells mixed with eosinophils and many histiocytes, some of them presenting discrete features of hemophagocytosis. The neoplastic cells were CD3, CD5, CD8 and HLA-DR positive but failed to show CD30 antigen. dna molecular analysis displayed simultaneous rearrangements of the genes coding for the delta chain of the T-cell receptor and for the Ig heavy chain. Increased serum levels of angiotensin converting enzyme and ferritin were found and probably induced by the reactive histiocytes. Immunoassays (ELISA) with antibodies directed against some cytokines and against the Tac peptide (sIL-2R) were performed. They demonstrated high serum levels of sIL-2R and a slight increase in GM-CSF, but neither IL-5 nor IL-3. The association of blood hypereosinophilia and histiocytic hyperplasia with a peripheral T-cell lymphoma is discussed.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
10/10. A solitary congenital self-healing histiocytosis. Report of a case and review of the literature.Congenital self-healing histiocytosis (CSHH), and especially the solitary variant, is a rare primary skin disorder. We report on a newborn with a congenital solitary ulcerated skin nodule. Extracutaneous involvement was not found. A skin biopsy was performed at the age of 44 days and revealed a dense dermal infiltrate of large histiocytic cells. Immunohistochemical study revealed that the cells of the dermal infiltrate were Langerhans' cells which were strongly positive for S- 100 and negative for lysozyme, leukocyte common antigen and alpha-1-antichymotrypsin. The skin lesion involuted spontaneously over the next month without any treatment. The clinical, histopathological and immunohistochemical results fulfilled the criteria of solitary CSHH. We herein report the first case of CSHH in taiwan and the twelfth case of solitary CSHH in the world.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
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