Cutaneous bacillary angiomatosis in a patient with chronic lymphocytic leukemia.

BACKGROUND: Bacillary angiomatosis is a recently described vascular disorder that is associated with infection by Bartonella henselae (formerly known as Rochalimaea henselae) and Bartonella quintana (formerly known as Rochalimaea quintana); this disorder usually occurs in patients with human immunodeficiency virus infection. We report a case of cutaneous bacillary angiomatosis that occurred in a patient with chronic lymphocytic leukemia. OBSERVATIONS: A 55-year-old man with chronic lymphocytic B-cell leukemia, Rai stage IV, presented with multiple angiomatous papules that clinically resembled pyogenic granulomas. Histopathologic examination revealed circumscribed lobules of small vessels with plump endothelial cells, numerous neutrophils, and abundant nuclear dust; these features were diagnostic for bacillary angiomatosis. The diagnosis was confirmed by the Grocott-Gomori methenamine-silver nitrate stain that revealed argyrophilic bacteria and by ultrastructural demonstration of bacillary structures with trilaminar walls. Treatment with clarithromycin led to complete resolution of the lesions within 4 weeks. CONCLUSIONS: This case emphasizes that (1) bacillary angiomatosis must be considered in the differential diagnosis of vascular lesions in immunocompromised patients without human immunodeficiency virus infection, (2) Grocott-Gomori methenamine-silver nitrate stain is a simple and satisfactory alternative to the Warthin-Starry stain for the demonstration of bacilli in this condition, and (3) clarithromycin is an effective oral antibiotic for the treatment of this disease.