[Anaerobic infections in internal medicine]

Virtually all anaerobic infections arise endogenously. Underlying conditions often associated with anaerobic infections are diabetes mellitus, corticosteroid therapy, leukopenia, immunosuppression, vascular disease, tissue anoxia and aerobic infection. Various enzymes and other materials produced by the anaerobes act as virulence factors. There is an impressive incidence of anaerobic bacteria in infections involving the lung and pleural space, in liver abscesses, biliary tract infections, skin and soft-tissue infections and bacteremia. Location of infection, previous therapy with aminoglycoside antibiotics and other clues suggest that a given patient may have an anaerobic infection. Whenever possible, a specimen should be obtained by needle and syringe to avoid normal flora. Specimens must be transported to the laboratory under anaerobic conditions. Therapy involves the use of antimicrobials, preferably drugs with a high activity against beta-lactamase-producing Bacteroides spp.