Systemic mastocytosis.

Mastocytosis is a disease characterized by an abnormal increase in mast cells. Rare in occurrence, protean in its manifestations, it is a disease which is very seldom thought of and hence, possibly even overlooked. The last few decades have witnessed an upsurge in the understanding of the physiology and pathobiology of mast cells. Better means for diagnosis and follow-up have become available. Once a diagnosis is established histamine antagonists remain the mainstay of treatment. Most patients live and die with the disease rather than of it. The objective of this review is to discuss this entity with a special focus on diagnosis and treatment.