Biopsy diagnosis in human immunodeficiency virus infection and acquired immunodeficiency syndrome.

Human immunodeficiency virus infection and the complications of the acquired immunodeficiency syndrome produce a broad spectrum of lesions affecting all organs and tissues. They are caused by uncommon etiologic agents and characterized by unusual location, multiplicity, rapid progression, and tendency to generalization. Cellular reactions are inefficient and histologic appearances frequently atypical. Tissue biopsy, most often endoscopic, with microscopic examination, is the method predominantly used for achieving the required rapid, definitive diagnosis. This article reviews the lesions commonly seen in biopsy specimens of human immunodeficiency virus infection and acquired immunodeficiency disease syndrome, their characteristic histologic features, and their differential diagnosis.