Histiocytosis Syndromes of Childhood: A report of four cases.

Histiocytosis Syndromes of Childhood (HSC) are a group of rare and diverse disorders characterized by aggressive proliferation or accumulation of cells of monocyte - macrophage system of bone marrow. The clinical spectrum of this syndrome is distinctly varied. The exact pathophysiology of HSC is yet to be determined; however, evidence suggests that one of the subtypes, Hemophagocytic Lymphohistiocytosis, is due to decreased Natural Killer cell activity, resulting in increased activation of other T cell subtypes and production of cytokines. We present four cases of HSC managed at our center between October 2008 & February 2010.