Bacteriology of aspiration pneumonia in children.

Aspiration pneumonia in adults has been shown to involve anaerobes about 90% of the time. Studies of the bacteriology of aspiration pneumonia in children done in the past have either failed to exclude the oral and upper respiratory tract flora or have not utilized proper anaerobic culture techniques or both. In the present study. 74 institutionalized children with aspiration pneumonia were studied by percutaneous transtracheal aspiration. Their average age was 8 years. Fifty-two patients had pneumonitis, 12, necrotizing pneumonia, and 10, lung abscess. Only one patient (with lung abscess) had a complicating empyema. There was an average of five bacteria isolated per specimen--2.8 anaerobes and 2.2 nonanaerobes. The predominant anaerobic isolates were Gram-positive cocci, Bacteroides melaninogenicus, and fuso-bacteria; there were ten patients who yielded members of the Bacteroides fragilis group. The predominant nonanaerobes were alpha-hemolytic streptococci, Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. Thus, aspiration pneumonia in children, as in adults, commonly involves anaerobic bacteria. When aspiration occurs in a medical institution, nosocomial pathogens which are aerobic or facultative will also often be involved, in both children and adults.