histiocytosis


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histiocytosis

 [his″te-o-si-to´sis]
a condition marked by the abnormal appearance of histiocytes in the blood.
Langerhans cell histiocytosis a generic term that encompasses a group of disorders characterized by proliferation of Langerhans cells, which are specialized cells found in the epidermis that function as part of the immune system. These disorders are believed to arise from disturbances in regulation of the immune system. Children are more often affected than adults, and the bone marrow, endocrine system, and lungs may be involved (the lungs are affected more commonly in adults than in children). Langerhans cell histiocytosis is divided into unifocal and multifocal variants; there is also an acute, disseminated form (letterer-siwe disease). This group of disorders was formerly called histiocytosis X and was classified in three forms: Letterer-Siwe disease, Hand-Schüller-Christian disease, and eosinophilic granuloma. Called also eosinophilic granuloma, eosinophilic granulomatosis, and Langerhans cell granulomatosis.
Langerhans cell histiocytosis, acute disseminated Letterer-Siwe disease.
Langerhans cell histiocytosis, multifocal Langerhans cell histiocytosis occurring as erosive accumulations of proliferating Langerhans cells. It occurs most commonly in the marrow cavities of bones, but may also affect the skin, gingiva, lungs, and stomach. When the triad of involvement of the bones of the skull, exophthalmos, and diabetes insipidus is present, it is referred to as Hand-Schüller-Christian disease.
Langerhans cell histiocytosis, unifocal Langerhans cell histiocytosis occurring as a single osteolytic lesion, usually in a long or flat bone; it may be asymptomatic or may produce bone pain, tenderness, and swelling and, sometimes, pathologic fracture.
histiocytosis X former name for Langerhans cell histiocytosis.

his·ti·o·cy·to·sis

(his'tē-ō-sī-tō'sis),
A generalized proliferation of histiocytes.
Synonym(s): histocytosis

histiocytosis

/his·tio·cy·to·sis/ (-si-to´sis) a condition marked by an abnormal appearance of histiocytes in the blood.
acute disseminated Langerhans cell histiocytosis  Letterer-Siwe disease.
Langerhans cell histiocytosis  a generic term for a group of disorders characterized by proliferation of Langerhans cells (q.v.), believed to arise from disturbances in regulation of the immune system. Lesions may be unifocal or multifocal and may involve the bone marrow, endocrine system, or lungs.
sinus histiocytosis  a disorder of the lymph nodes in which the distended sinuses are filled by histiocytes, as a result of active multiplication of the littoral cells.
histiocytosis X  former name for Langerhans cell h.

histiocytosis

(hĭs′tē-ō′sī-tō′sĭs)
n. pl. histiocyto·ses (-sēz)
Any of several diseases characterized by the abnormal proliferation of histiocytes in the tissues or organs.

his·ti·o·cy·to·sis

(his'tē-ō-sī-tō'sis)
A generalized multiplication of histiocytes.
Synonym(s): histocytosis.

histiocytosis

One of several disorders in which HISTIOCYTES occur in abnormal numbers, in localized areas, without any of the usual causes, such as infection. Histiocytosis LESIONS may be single or multiple. The condition is also known as histiocytosis X.

histiocytosis

a condition marked by the abnormal appearance of histiocytes in the blood.

cutaneous histiocytosis
a benign proliferative disease in dogs, particularly Collies and Shetland sheepdogs. there are multiple plaques or nodules in the skin or subcutaneous tissue. The cause is unknown.
lipid histiocytosis
Niemann-Pick disease.
malignant histiocytosis
a systemic, progressive invasive proliferation of neoplastic histiocytes. Recognized as a familial disorder in Bernese mountain dogs with clinical signs of respiratory disease, involvement of the central nervous system, and anemia.
systemic histiocytosis
a proliferative disorder of histiocytes with infiltrates in the skin and lymph nodes. Occurs in young Bernese mountain dogs.
References in periodicals archive ?
Mutations in SLC29A3, encoding an equilibrative nucleoside transporter ENT3, cause a familial histiocytosis syndrome (Faisalabad histiocytosis) and familial Rosai-Dorfman disease.
Bronchoalveolar lavage fluid analysis provides diagnostic information on pulmonary Langerhans cell histiocytosis.
Patients with hematopoietic, hepatic, splenic or pulmonary involvement are considered at risk for multisystem disease in the risk stratification system of the Histiocytosis Society, and treatment protocols were designed accordingly (10) The prognosis of LCH patients with multisystem involvement is poor.
A rare cause of goiter: Langerhans cell histiocytosis of the thyroid.
Primary langerhans cell histiocytosis of the vulva: report of a case and brief review of the literature.
Langerhans' cell histiocytosis in paediatric population: presentation and treatment of head and neck manifestations.
Sinus histiocytosis with massive lymphadenopathy (SHML) is a rare and benign source of lymphadenopathy of unknown aetiology, first described in 1969 by Rosai and Dorfman (cited by Moore et al.
Erdheim-Chester disease of the breast associated with Langerhans-cell histiocytosis of the hard palate.
Imatinib mesylate for platelet-derived growth factor receptor-beta positive Erdheim-Chester histiocytosis," Blood, vol.
Gaitonde, "Multifocal, extranodal sinus histiocytosis with massive lymphadenopathy: an overview," Archives of Pathology and Laboratory Medicine, vol.
A biopsy specimen was obtained, and histopathology identified Langerhans cell histiocytosis.