A 45 year old, HIV positive patient presents with features of pneumonia. Characteristic histopathological features suggesting pneumocystis carinii pneumonia is:
Answer is B (Eosinophilic Alveolar Exudate): The most characteristic histoputhological feature of pneumocystis carinii pneumonia in adults is predominantly alveolar, foamy vacuoloted, eosinophilic exudates. Interstitial pneumonitis is usually mild and shows infiltration with PML and mononuclear cells.
Prominent Interstitial Pneumonitis
Eosinophilic Alveolar Exudates
Prominent mononuclear cells in Alveolar exudates
Neutrophilic infiltration of alveolar interstitium