BACKGROUND Rosai-Dorfman disease (RDD) is a rare benign idiopathic histiocytic proliferation. Most commonly reported cases are lymph nodal. Only 30-40% of cases occur in extranodal sites. Although the morphological features of RDD are well documented, there is limited information about the morphometric variations in the histiocytes of this entity. METHOD Twenty-two cases of RDD diagnosed on f...

The authors describe a case of histiocyte-rich B-cell lymphoma (HR-BCL), a variant of diffuse large B-cell lymphoma, in a 51-year-old man. The patient presented with large axillary lymphadenopathy. Histopathologic and immunohistochemical examination of lymph node biopsy revealed diffuse effacement of the lymph node architecture by reactive histiocytes and neoplastic CD20 positive B cells. ...

Studies of passive transfer of cellular resistance, as manifested by refractoriness to necrotization with virulent tubercle bacilli, have shown that immune histiocytes or immune lymphocytes were effective transferring agents; immune polymorphonuclear leucocytes and immune serum as well as comparable cells from normal animals lacked this capacity. Comparisons of immune histiocytes and immune lym...

Intestinal changes, mainly in the jejunum, were investigated in 13 cases of malignant histiocytosis at necropsy and who had presented as lethal midline granuloma. Villous atrophy with crypt hyperplasia was observed in all cases, and a proliferation of atypical histiocytes was observed in seven cases. In the remaining cases, histiocytes with normal morphology increased in number. These findings ...

Localized Leishmania Lymphadenitis (L.L.L) is a self limited clinical presentation of cutaneous leishmaniasis. Microscopic findings in L.L.L are very similar to Toxoplasma lymphasenitis. In all cases, an intensive microscopic search should be done for Leishman bodies. In this study, we describe our micro...

The rate and form of growth of Histoplasma capsulatum within histiocytes derived from homothermic and poikilothermic animals, and incubated at 25, 30, and 37 C, are described. The generation time of the fungus in mouse cells incubated at 37 and 25 C was 11 and 24 hr, respectively. Blastospore formation was progressively retarded in cells at 25 C, and this retardation was accompanied by germinat...

Howard, Dexter H. (University of California, Los Angeles). Intracellular behavior of Histoplasma capsulatum. J. Bacteriol. 87:33-38. 1964.-The tinctorial characteristics and intracellular generation time of Histoplasma capsulatum within mouse histiocytes maintained in tissue culture were studied. The appearance of viable and nonviable cells of H. capsulatum was observed after staining with the ...

Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy) is a benign systemic proliferative disorder of histiocytes resembling the sinus histiocytes of lymph nodes. The typical clinical features of this disease include bilateral painless lymphadenopathy, fever, and polyclonal hyperglobulinaemia. The condition may present with extranodal involvement in 43% of cases, and cutaneous...

In the spleens and bone marrows of patients with thalassemia, we have consistently observed PAS-positive histiocytes that contain numerous cytoplasmic bodies surrounded by a single membrane and filled with bundles of fine fibrils (typical thalassemia storage cells). In addition to the characteristic cytoplasmic bod ies, some histiocytes contained leukocytes, erythrocytes, platelets, and plasma ...