Review articleMicrobiology and management of human and animal bite wound infections
Section snippets
Microbiology
A variety of organisms that generally result from the aerobic and anaerobic microbial flora of the oral cavity of the biting animal, rather than the victim's own skin flora, can be recovered from bite wounds. Most infections are polymicrobial. The role of anaerobes in bite wound infections has been increasingly appreciated [8], [9], [10], [11], [12]. Anaerobes have been isolated from more than two thirds of human and animal bite wound infections, especially those associated with abscess
Pathogenesis
The potential for infection of human or animal bites is great. For example, a dog's teeth are not sharp but can exert a pressure of 200 to 450 psi [59]. This pressure is strong enough to perforate sheet metal and result in a crush injury with much devitalized tissue, rather than a laceration. The average dog mouth harbors more than 64 species of bacteria, including S. aureus, P. multocida, anaerobic bacteria (especially of the pigmented Prevotella and Porphynomonas sp) and CDC types IIj (
Diagnosis
The symptoms occurring after a bite depend on the animal species inflicting the injury. Immediate local or systemic symptoms can be severe after venomous animals (snake, lizard, spider, and so forth). Human or dog bites generally do not cause immediate symptoms different from those of a laceration injury. Because of the direct introduction of oral and skin flora into the wound, however, if an infection occurs, it develops quite rapidly. The signs of infection can include redness, swelling, and
Management
Wound management includes the administration of proper local care and the utilization, when needed, of proper antimicrobial agents. Evaluation and wound care for bites include recording medical history (animal involved, provoked or unprovoked attack, current medications, splenectomy, mastectomy, allergies, chronic disease, and immunosuppression); examining the wound and related structures (odor of exudates, depth, type, and location of wound, range of motion, joint involvement, edema or crush
Complications
Hand wounds present a special problem, because 30% or more become infected [59], [61]. Because of the presence of avascular tendon and sheath spaces, the propensity for spread of infection, and disastrous results of such infection on function, the threat of complications after bite wounds must be addressed. In addition to local wound infection, other complications include lymphangitis, local abscess, septic arthritis, tenosynovitis, and osteomyelitis [33], [67]. Rare complications include
References (79)
- et al.
Human bites of the hand: twenty years of experience
J Hand Surg
(1977) Epidemiologic and clinical aspects of animal bite injuries
JACEP
(1979)- et al.
2000 annual report of the American Association of Poison Control Centers Toxic Exposure Surveillance System
Am J Emerg Med
(2001) - et al.
Staphylococcus intermedius: clinical presentation of a new human dog bite pathogen
Ann Emerg Med
(1989) - et al.
The emergency management of moray eel bites
Ann Emerg Med
(1992) - et al.
Dog bite wounds and infection: a prospective clinical study
Ann Emerg Med
(1980) - et al.
Dog bite wounds and infection: a prospective clinical study
Ann Emerg Med
(1980) - et al.
Actinobacillus suis infection after a pig bite
Lancet
(1996) Haemophilus influenzae cellulitis after bite injuries in children
J Pediatr Surg
(2000)Treatment of pig bites
Lancet
(1996)