MEDIASTINAL AND HILAR LYMPHADENOPATHY DUE TO PNEUMOCYSTIS-CARINII INFECTION IN AIDS PATIENTS - CT FEATURES

Objective: Extrapulmonary involvement by Pneumocystis carinii (PC) in acquired immunodeficiency syndrome (AIDS) patients is uncommon. Our pu rpose is to describe three AIDS patients with low cluster differentiat ion cell (CD4) counts, who were receiving aerosol pentamidine prophyla xis, and who had large noncalcified hilar and mediastinal lymphadenopa thy. Materials and Methods: Chest radiography, CT, and clinical and la boratory records of three AIDS patients who had radiographic evidence of mediastinal and hilar lymphadenopathy were retrospectively reviewed . Results: Symptoms were quite similar in all patients: weight loss, f ever, cough, and mild dyspnea. Mediastinal and hilar widening was noti ced on chest radiography. Contrast-enhanced chest CT revealed multiple noncalcified lymphadenopathy with supracarinal predominance in all ca ses. Mediastinoscopy with mediastinal and hilar lymph nodes sampling w as performed in all patients. Histologic examination of the biopsy spe cimens demonstrated a necrotic foamy tissue without any calcification, and silver stain coloration showed abundant PC organisms in each case . Conclusion: In AIDS patients, PC infection should be considered as a possible cause of noncalcified hilar and mediastinal lymphadenopathy along with such possibilities as atypical infections and neoplasms, es pecially in severely immunocompromised hosts (low CD4) with aerosol pe ntamidine prophylaxis.