HRCT appearance of systemic mastocytosis involving the lungs.

Systemic mastocytosis is an uncommon disease of unknown prevalence. Most patients clinically present with urticaria pigmentosa. The diagnosis is made by finding increased mast cells in the involved tissues. Pulmonary involvement in systemic mastocytosis is rare. The chest radiographic findings include reticulonodular opacities and lung nodules. We present a case of histologically proven pulmonary and skeletal systemic mastocytosis (AKA systemic mast cell disease) associated with a hematologic condition, including the high-resolution computed tomographic findings of this disorder.