Anaerobic infections in childhood.

Anaerobic bacteria are part of the normal flora of mucous membranes and outnumber aerobic bacteria in the oral cavity and gastrointestinal tract. Anaerobes can be isolated from pediatric patients with various infections when appropriate techniques for transportation and cultivation of samples are employed. Frequently anaerobes are isolated in combination with other facultative or aerobic bacteria. The genera or groups of anaerobes most frequently isolated from pyogenic infections in children are (in order of decreasing frequency) OFFteroides, Clostridium, gram-positive cocci, Fusobacterium, gram-positive rods (Eubacterium, Lactobacillus, Propionibacterium, Actinomyces, and Bifidobacterium), and gram-negative cocci (Veillonella and Acidaminococcus). Clostridium perfringens causes bacteremia and wound infections. Clostridium botulinum can produce a paralytic toxin that causes a lethal illness in adults and a paralytic syndrome in infants. Clostridium difficile can cause antibiotic-associated colitis or diarrhea. Bacteroides fragilis is most frequently involved in intraabdominal infections, infections of the female genital tract, subcutaneous abscesses, and bacteremia. Bacteroides melaninogenicus and Bacteroides oralis are the predominent anaerobes in orofacial infections and aspiration pneumonia. Fusobacterium species are pathogens in aspiration pneumonia, brain abscesses, and orofacial infections. Anaerobic gram-positive cocci can be recovered from all types of infections but predominate in respiratory tract and intra-abdominal infections. Recognition of the pathogenic qualities of the various anaerobic organisms can assist in their prompt identification and in the initiation of appropriate therapy.