Abstract
The causes and pathogenesis of severe childhood pneumonia in a developing country were studied in lungs removed at autopsy from 119 Bangladeshi children who presented with pneumonia and/or diarrhea. Pneumonia was observed in 93 patients. Morphologic features included acute alveolar exudate In 51 % (of the 93 patients), necrotizing pneumonia in 31%, interstitial pneumonia in 22%, and caseating granulomas in 4%, while a mixed pattern occurred in 16% of patients. Causes of pneumonia were Gram-negative bacteria in 27%, pneumococcus in 8%, cytomegalovirus (CMV) in 8%, Pneumocystis carinii (PC) in 4%, mycobacteria in 3%, aspergillus in 3%, mixed anerobes in 3%, viral (not CMV) in 2%, Staphylococcus aureus in 1 % and ascaris in 1%. Two causative agents were identified in 7% of patients. In 46% of the cases, no etiologic agent was identified. Our data suggest that most pneumonias had a bacterial etiology; however, viruses, including CMV, and other opportunistic organisms such as PC, were also important pathogens. Gram-negative pneumonia was partially attributed to concomitant intestinal infections. Opportunistic infections resulted from malnutrition and debilitated host defenses during prolonged fatal illnesses.