30 yo F presents c/o bite wound to her face by her pet cat. The cat was nervous because she was in a new home, otherwise the cat did not exhibit any unusual behavior and has all its vaccines. The patient is uptodate with vaccines as well. The bite occurred just prior to arrival. On exam, 2 superficial puncture sites are noted on her left cheek. What do you do?
a) Clean/Irrigate, PO antibiotics, primary suture closure
b) Clean/Irrigate, PO antibiotics, leave the wound to close by secondary intention
c) Clean/Irrigate, no antibiotics, primary suture closure
d) Clean/Irrigate, no antibiotics, leave the wound to close by secondary intention
Answer:
C) As per Rosen’s and ROSH review prophylactic antibiotics are not necessary for simple cat or dog bites, however are recommended for high-risk wounds, which include: hand wounds, deep structure involvement (tendon, joint, bone), delayed presentation (>12 hours), contaminated wounds with foreign bodies or devitalized tissue, deep puncture wounds, and high-risk patients.
A Cochrane review concluded there was no evidence that antibiotic prophylaxis was effective for cat or dog bites, although the authors also concluded that cat or dog bites to the hands (where most bites occur from domestic animals) benefit from prophylaxis. For very high-risk bites, such as to the hand, intravenous antibiotic prophylaxis in the ED should be considered.
The face is highly vascularized and is of cosmetic importance so an attempt should be made to primary close the wound. The patient should followup for wound checks. Note for high risk wounds, allow the wounds to close by secondary intention.
Other Animal Bites: Although there are no studies to support the practice, antimicrobial prophylaxis for bites from other mammals is often provided.Rosen’s recommends antibiotic prophylaxis with coverage against Pasteurella for pig bites or camel bites, for high-risk patients, and for bites on the hand. Rodent bites and those from most other species have a lower risk of wound infection, so prophylaxis is not indicated. The anecdotal data available on wild animal bites suggest that the organisms involved are similar to those in domestic animals,including staphylococci, streptococci, and anaerobes. There are no studies regarding the use of antibiotic prophylaxis in these injuries
In case you ever have a patient that was bitten by a monkey, be concerned for Monkey B Virus infection. Although human cases of infection are extremely rare given the thousands of potential exposures each year, the mortality rate for B virus infection in the absence of antiviral therapy is over 70%. Prophylaxis with antiviral therapy is individualized based on the risks of the exposure. Prophylaxis is not recommended if the skin remains intact or if the exposure occurred with a nonmacaque species. If prophylaxis is undertaken, the recommended therapy is valacyclovir (1 g orally [PO] q8h × 14 days) or acyclovir (800 mg PO 5 times daily × 14 days).
