Mixed organic brain syndrome as a manifestation of systemic mastocytosis.

Systemic mastocytosis is a disease characterized by an excessive accumulation of mast cells, and associated with skin lesions, flushing, diarrhea, tachycardia, and psychiatric manifestations. In order to define more clearly the psychiatric manifestations, ten patients with this disorder underwent unstructured psychiatric interviews and a battery of psychologic testing. Both revealed a pattern of cognitive and affective changes in the majority of these patients, best categorized as an atypical or mixed organic brain syndrome. The cognitive changes consisted of diminished attention and memory, and the affective changes of anger, irritability, and, to a lesser extent, depression. These manifestations fluctuated with the level of disease activity, and appeared in some cases to respond to histamine antagonists and disodium cromoglycate, medications used to control the excessive mast cell activity. It is important for psychiatrists to be aware that mental status changes can represent psychiatric manifestations of mastocytosis, a readily treatable medical disorder.