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. Key words: Histiocytosis Syndromes of Childhood; Langerhan’s cell Histiocytosis (LCH); Hemophagocytic Lymphohistiocytosis (HLH); Macrophage Activation Syndrome (MAS). DOI: 10.3126/jnps.v30i3.3923J Nep Paedtr Soc 2010;30(3):171-174
Natural killer cell dysfunction: A common pathway in systemic-onset juvenile rheumatoid arthritis, macrophage activation syndrome, and hemophagocytic lymphohistiocytosis?