ABSTRACT
BACKGROUND: Pulmonary malakoplakia is an uncommon disorder, with 24 previously reported cases, only 4 of which were diagnosed by bronchial washings, bronchial brushings or aspiration cytology. We report a case that was diagnosed initially by computed tomography (CT)-guided fine needle aspiration (FNA) cytology. CASE: A 56-year-old male with follicular small cleaved cell lymphoma had a 10-cm left lower lobe mass compressing the main bronchus to that lobe. A transthoracic, CT-guided FNA specimen consisted predominantly of foamy macrophages, many of which contained typical Michaelis-Gutmann bodies. Microbiologic cultures identified Rhodococcus equi. A subsequent transbronchial biopsy and left pneumonectomy specimen confirmed the cytologic diagnosis. CONCLUSION: Pulmonary malakoplakia associated with R equi pneumonia is a rare lesion that is essentially limited to immunocompromised hosts. Awareness of the FNA cytomorphology of this lesion permits resolution of the typical clinical differential diagnosis of pulmonary masses in the immunocompromised host and can facilitate treatment.
