Trauma Animal Bites ============ þ Rabies þ Bacterial infection in bites: - large study found Pasturella most common, also staph and strep, also mixed anaerobes, but Eikenella corrodens not common (common in human bites), nor Bartonella (agent of cat-scratch fever) [# Talan, N Engl J Med, get citation from Mike T.] - cehpalexin and diclox don't cover - doxy doesn't cover - trovan will cover past, staph, strep, anaerobes, but FDA says no - azithromycin will cover all four, but erythro and claritho won't cover anerobes - PCN+Keflex, Augmentin (too expensive, causes diarrhea), Azithro (if pen allergic) þ Prophylactic antibiotics for dog bites? - only for high-risk wounds: hand, deep punctures, dirty contaminated wounds, and immunocompromise (diabetics, elderly, splenectomized patients) - only 9-16% become infected, many with minor infections - meta-analysis does show 50% reduction of infections with prophlactic antibiotics, but must treat lots of patients and not clear if treating all is cost-effective (doubtful) [Callaham M. Prophylactic antibiotics in dog bite wounds: Nipping at the heels of progress. Ann Emerg Med 1994;23:577-579.] [#???. Prophylactic antibiotics for bites: Metaanalysis. Ann Emerg Med 1994] Bites: Arch Emerg Med 2000:7:157 2 hours closure for bites infection rate 5.5% (non-bites 3-7%) Maimaris Arch Emerg Med 1988;5:156 Low infection rates Few sutures as possible? No studies? Antibiotics? Cummings Ann Emerg Med 1994:23:535 - NNT 14 to prevent 1 infection. Wide confidence intervals of individuals, but 44% reduction. Yes, but only for hands. 90% reduction in infections in hands, NNT is 4. þ PCN allergic patient with dogbite - Ceftin (cefuroxime) or Suprax (Cefixime) (really a second generation, not third as advertised; not good for Staph). þ DF-2 gram - rods Capnocytophagia canimorsus and Capnocytophaga cynodegui - after pet bite, may develop sepsis in normal host; - reason to prophylax all people with pet bites - DF-2 now renamed Capnocytophaga canimorsus and Capnocytophaga cynodegui. - particularly a problem for asplenic individuals þ Early cellulitis from dog/cat bite - likely to be Pasturella multocida - Diclox and Keflex don't cover Pasturella well. - Erythro has a history of some treatment failures but may be OK. - but TCN and doxycycline have poor tissue penetration. þ Human bites: - Eikenella corrodens is big anaerobic cause of cellulitis "Most of these wounds are polymicrobial. Though Eikenella corrodens is a classically considered pathogen in these wounds, it is actually isolated by itself in only 15% of cases. Strep viridans is seen in nearly 100% of these wounds. Other bacteria include Staph epidermidis (53%), Corynebacterium (41%), Staph aureus (29%), Bacteriodies (82%), and Peptostreptococcus (26%). Gram negative organisms may predominate in bites received from hospitalized or institutionalized patients. [Ref: Knopp, Stack & Storrow, ATLAS OF EMERGENCY MEDICINE, McGrawHill, 1997, p 285.] [The Sanford Guide to Antimicrobial Therapy, 28th Ed., 1998] Eikenella similar to pasturella so can use similar antibiotics, see above. - Penicillin: good coverage - Clindamicin: probably doesn't cover, but erythro will. - Erythro: covers other anaerobes. þ Primary closure of bites: - It appears to be safe to close dog bite wounds primarily. [Maimaris C, Quinton DN. Dog-bite lacerations: a controlled trial of primary wound closure. Arch Emerg Med 1988 Sep;5(3):156-61.] Abstract: [Callaham ML. Treatment of common dog bites: infection risk factors. JACEP 1978 Mar;7(3):83-7.] Abstract: þ Antibiotics for Bites: - Antibiotic prophylaxis has generally not been effective. [Guy RJ, Zook EG. Successful treatment of acute head and neck dog bite wounds without antibiotics. Ann Plast Surg 1986 Jul;17(1):45-8.] Abstract: [Skurka J, Willert C, Yogev R. Wound infection following dog bite despite prophylactic penicillin. Infection 1986 May-Jun;14(3):134-5.] Abstract: [Jones DA, Stanbridge TN. A clinical trial using co-trimoxazole in an attempt to reduce wound infection rates in dog bite wounds. Postgrad Med J 1985 Jul;61(717):593-4.] Abstract: [Rosen RA. The use of antibiotics in the initial management of recent dog-bite wounds. Am J Emerg Med 1985 Jan;3(1):19-23.] Abstract: [Brakenbury PH, Muwanga C. A comparative double blind study of amoxycillin/clavulanate vs placebo in the prevention of infection after animal bites. Arch Emerg Med 1989 Dec;6(4):251-6.] Abstract: [Elenbaas RM, McNabney WK, Robinson WA. Prophylactic oxacillin in dog bite wounds. Ann Emerg Med 1982 May;11(5):248-51.] Abstract: [Dire DJ, Hogan DE, Walker JS. Prophylactic oral antibiotics for low-risk dog bite wounds. Pediatr Emerg Care 1992 Aug;8(4):194-9.] Abstract: - As single agents PCN , co-trimoxizole , penicillinase resistant antibiotics and erythromycin and oxacillin are ineffective. Amoxicillin/clavulanate may be effective for delayed presentations . - Human bites of the *hand* have recently been shown to benefit from antibiotic coverage. [Zubowicz VN, Gravier M. Management of early human bites of the hand: a prospective randomized study [see comments]. Plast Reconstr Surg 1991 Jul;88(1):111-4.] Abstract: - For cat bites, there is a non-significant trend favoring antibiotic prophylaxis for puncture wounds and those of the lower extremity. [Dire DJ Cat bite wounds: risk factors for infection. Ann Emerg Med 1991 Sep;20(9):973-9.] - In an early (small) study oxacillin was found to be effective for cat bites. Only one problem here: 3/4 of those infected had Pasturella, an organism that is not sensitive to oxacillin! - The data thus appears to be incomplete. A reasonable plan is to prescribe antibiotics and treat by an open technique wounds of the hands, feet and possibly puncture wounds. Patients with impaired host defences MAY benefit from antibiotics as well. I'm not sure how many you'll have to treat, though, to prevent one case of Capnocytophaga canimorsus (DF2) sepsis. All the rest can be closed without antibiotic coverage. - Current recommendation is that dog bite wounds should be prophylaxed if they are high risk i.e., delayed presentation, immune compromise, upper extremity, puncture type wound etc. [de Melker HE, de Melker RA. [Dog bites: publications on risk factors, infections, antibiotics and primary wound closure] Ned Tijdschr Geneeskd 1996 Mar 30;140(13):709-13.] Abstract: - References: