histiocytic lesionAn aggregate of histiocytes, which may be benign, indeterminant, or malignant in proliferative potential; to reduce confusion, it has been suggested that histiocytoses be subdivided into different categories
Histiocytic lesions-Behavior classification
• Familial histiocytosis with eosinophilia A chronic disease of infants with recurring bacterial infections, diarrhea, eczema, alopecia, associated with immunodeficiency
• Sinus histiocytosis with massive lymphadenopathy Rosai-Dorfman disease A disease most common in adolescent blacks with massive cervical lymphadenopathy as well as enlargement of extranodal (orbit, skin, bone, salivary gland, testis) lymphoid tissues
• Virus-associated hemophagocytic syndrome A condition induced by viral infections, often accompanied by abnormal liver function tests, coagulation assays and pancytopenia Pathology Histiocyte hyperplasia, hemophagocytosis and replacement of native bone marrow elements
• Histiocytosis X, aka Langerhans' cell histiocytosis, see there.
• Reactive hemophagocytic syndrome, see there.
• Histiocytic medullary reticulosis see there.
• Histiocytic proliferations, eg—acute monocytic leukemia (FAB M3), histiocytic lymphoma see there, malignant histiocytosis–see there.