Histopathological and electron microscopical features of skin lesions in a patient with bartonellosis (verruga peruana).

Chronic verruga nodules taken from a patient with Bartonellosis (verruga peruana) were studied. Histologically, specimens of all the verruga nodules had features consistent with granulomatous lesions with extensive infiltration of various types of cells along with the proliferation of capillaries. The sections were predominantly infiltrated with neutrophils and endothelial cells; histiocytes, plasma cells, lymphocytes and mast cells were also visible to some extent. The blood vessels were dilated, and many rounded and swollen endothelial cells were located peripherally; a huge number of neutrophils invaded the vessels. Electron microscopically, large number of organisms were seen in different stages of the life cycle in the stroma. Furthermore, organisms were regularly seen either in close contact or existing inside the cytoplasm of neutrophils, suggesting the phagocytic role of these cells. No organism was found inside any endothelial cells or histiocytes.