Diagnosis of Pneumocystis pneumonia by bronchoalveolar lavage cytology: experience at a tertiary care centre in India.

ABSTRACT

BACKGROUND: Diagnosis of Pneumocystis pneumonia requires morphological demostration of P. carinii (now re-named as P. jiroveci). Although bronchoalveolar lavage (BAL) fluid cytology constitutes a formidable tool for detecting this infection, few studies on the utility of BAL cytology in diagnosing PCP are available from India. The present study reports the clinical spectrum, cytomorphological features and the utility of BAL cytology in diagnosing Pneumocystis infection from a tertiary care centre in India. METHODS: Retrospective study of 13 patients with PCP, diagnosed on examination of BAL fluid. RESULTS: The mean age of the patients was 41.2 years. One patient had human immunodeficiency virus (HIV) infection, while the other 10 were renal transplant receipients on immunosuppressive therapy. The immune status of two patients was unknown. Fever, cough and shortness of breath were the main presenting symptoms. Radiological diagnosis of Pneumocystis pneumonia was offered in only one case. Foamy alveolar casts were present in all cases. Silver methanamine stain enhanced the rounded, helmet or cleft forms of sporozoites. Inflammatory infiltrate was mainly polymorphonuclear. CONCLUSIONS: BAL cytology, thus, constitutes a useful diagnostic modality for morphological documentation and reliable diagnosis of Pneumocystis pneumonia in an immunocompromised host. Pneumocystis pneumonia appears to be a common opportunistic infection in renal transplant receipients in India.