Human bites

I Human bites are third most common and the most serious.44 Before the availability of antibiotics, up to 20% resulted in amputation. Currently, human bite-associated amputation rates remain at 5%, secondary to vascular compromise and infectious complications.43... 

There are two types of human bite injuries. Occlusal injuries are inflicted by actual biting, whereas clenched-fist injuries are sustained when a person s closed fist hits another s teeth. Of the two, clenched-fist injuries typically are more prone to infectious complications.43,44... 

I Bite-wound infections generally are polymicrobial. On average, five different bacterial species can be isolated from an infected animal bite wound.3 Both the normal flora of the biter s mouth and that of the bite recipient s skin can be implicated. The bacteriology of the cat and dog mouth is quite similar. Pasteurella multocida, a gram-negative aerobe, is one of the predominant pathogens, isolated in up to 50% of dog and 75% of cat bites. S. viridans are the most frequently cultured bacteria from human bite wounds.3,43 Table 70-10 provides a comprehensive list of cat, dog, and human bite-wound pathogens. 

Most bite wounds require antibiotic therapy only when clinical infection is present. However, prophylactic therapy is recommended for wounds at higher risk for infection. These include human bites, deep punctures, bites to the hand, and bites requiring surgical repair.43... 

Infections can occur in up to 10% to 50% of patients with human bites. 

Management of bite wounds consists of aggressive irrigation and topical wound dressing, surgical debridement, and immobilization of the affected area. Primary closure for human bites is not generally recommended. Tetanus toxoid and antitoxin may be indicated. 

Successful antibiotic treatment should be continued until return of the temperature and peripheral leukocyte count to normal. However, persisting or returning fever and leukocytosis should lead to discontinuation of the antibiotics and prompt re-evaluation with imaging and surgical re-exploration rather than an escalation of the antibiotic treatment. Open complicated fractures should be treated for 5 days. Animal and human bites are treated with amoxycillin-clavulanic acid for 5 days. 

Dusheiko, G.M., Smith, M., Scheuer, P.J. Hepatitis C virus transmitted by human bite. Lancet 1990 336 503-504... 

While antimicrobial prophylaxis of dog or cat bites is not recommended routinely, patients with noninfected human bite injuries of the hand should be given prophylactic antimicrobial therapy with penicillin plus dicloxacillin for 3 to 5 days. Infected wounds of the hand, particularly clenched-fist injuries, should be treated with penicillin plus dicloxacillin or amoxicillin-clavulanate for 7 to 14 days. 

Human bites are the third most frequent type of bite. Infected human bites can occur as bites from the teeth or from blows to the mouth (clenched-fist injuries). Human bites generally are more serious than animal bites and carry a higher likelihood of infection than do most animal bites. Infectious complications occur in 10% to 50% of patients with human bites. ... 

Human bites generally are more serious and more prone to infection than animal bites, particularly clenched-flst injuries. While the force of a punch may sever a tendon or nerve or break a bone, it most often causes a breach in the capsule of the metacarpophalangeal joint, leading to direct inoculation of bacteria into thejointorbone. When the hand is relaxed, the tendons carry bacteria into deeper spaces of the hand, resulting in more extensive infection. ... 

Talan DA, Abrahamian EM, Moran GJ, et al. Clinical presentation and bacteriologic analysis of infected human bites in patients presenting to emergency departments. Qin Infect Dis 2003 37 1481-1489. 

Mann RJ, Hoffield TA, Farmer CB. Human bites of the hand Twenty years of experience. J Hand Surg 1977 2 97-99. 

Bunzli WF, Wright DH, Hoang AD, et al. Current management of human bites. Pharmacotherapy 1998 18 227-234. 

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