Three part question

In [healthy adults sustaining a human bite] do [prophylactic antibiotics] reduce [the incidence of infection]?

Clinical scenario

A healthy 25 year old man involved in an altercation with another man sustains a bite wound on the arm and presents to the Accident and Emergency Department. The wound is thoroughly cleaned and no signs of infection are present. You wonder whether prophylactic antibiotics are indicated to reduce the risk of wound infection in this patient.

Search strategy

Medline (1996–11/03) and Embase (1980–04/05). [human bites.mp OR exp Bites, Human/] and [penicillin.mp OR exp Penicillins OR antibiotics.mp OR exp Anti-Bacterial Agents OR erythromycin.mp OR ERYTHROMYCIN OR augmentin.mp OR exp Amoxicillin-Potassium Clavulanate Combination OR cephalosporin.mp OR exp CEPHALOSPORINS/] and wound infection.mp OR exp Wound Infection OR exp Postoperative Complications OR exp Bacterial Infections OR exp Surgical Wound Infection/or infection rate.mp] LIMIT to human and English language. Cochrane Edition 1 2005: “human bites”.

Search outcome

Medline and Embase: the search produced 89 papers, two of which were relevant to the original question. Cochrane: 32 citations. One review on mammalian bites. No new relevant papers on human bites found.

Comment(s)

The first study showed a clear benefit of giving prophylactic antibiotics for human bites to the hand. The second study did not demonstrate any significant reduction of infection rate with antibiotics for low risk superficial human bites, which were defined as those bites that penetrated only the epidermis and did not involve the hands, feet, or skin overlying joints or cartilaginous structures. It may be that antibiotic treatment of the low risk bites described is unnecessary. Until further studies show no reduction in infection rates for human bites, antibiotics should be given to all patients except those presenting with superficial bites outwith the areas described above. No prospective randomised controlled trials have investigated which particular antibiotics should be prescribed, and therefore antibiotic choice should follow local guidelines until studies have shown a particular antibiotic to be the most effective.

CLINICAL BOTTOM LINE

Prophylactic antibiotics should be given to all patients with human bites to the hands, feet, and skin overlying joints or cartilaginous structures, and to all patients with bites that penetrate deeper than the epidermal layer.