title: Pulmonary malakoplakia in a patient with the acquired immunodeficiency syndrome. Differential diagnostic considerations.
abstract: Malakoplakia is an unusual inflammatory condition characterized histopathologically by accumulations of benign macrophages, or von Hansemann's cells, that are associated with diagnostic intracellular and extracellular calcospherites, termed Michaelis-Gutmann bodies. Currently believed to represent an acquired defect of macrophage digestion, malakoplakia most commonly occurs in the urinary tract and is associated with a variety of infectious agents, notably gram-negative bacilli. We describe a patient with the acquired immunodeficiency syndrome who presented with a cavitating lingular mass. A transbronchial biopsy specimen revealed pulmonary malakoplakia, the seventh reported case of this condition and the second reported occurrence of pulmonary malakoplakia in a patient with acquired immunodeficiency syndrome. Microbiological cultures were positive for Rhodococcus equi. The significance of this finding, and the differential diagnosis of intra-alveolar histiocytic proliferations in patients with acquired immunodeficiency syndrome, is discussed.
authors: Department of Pathology, Emory University School of Medicine, Atlanta, Ga.
authors: D A
authors: DA
authors: Schwartz
authors: P O
authors: PO
authors: Ogden
authors: H M
authors: HM
authors: Blumberg
authors: E
authors: E
authors: Honig
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications / Q000473:pathology*; D001980:Bronchi / Q000473:pathology; D003937:Diagnosis, Differential; D006801:Humans; D008171:Lung Diseases / Q000150:complications / Q000473:pathology*; D008287:Malacoplakia / Q000150:complications / Q000473:pathology*; D008297:Male; D008875:Middle Aged