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Bites, Human: Treatment & Medication
Updated: Apr 23, 2009
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
Treatment
Prehospital Care
- Recovery of avulsed tissue parts (eg, ear, finger) is an important consideration for prehospital providers. Otherwise, human bite wound management generally is uncomplicated and involves temporary dressing and transport.
- Avulsed parts should be wrapped in sterile gauze dressing that is soaked with normal saline and placed in a plastic bag that is, in turn, placed in a container of ice water.
Emergency Department Care
The acute, non-infected human bite
- Cleanse and debride as usual
- Tetanus prophylaxis as indicated
- Antibiotic prophylaxis
- The literature regarding prophylaxis of human bite wounds is sparse. Only 2 randomized controlled trials directly address the question. In the first, patients with acute, non-infected human bites to the hand were randomized to prophylaxis with placebo, an oral cephalosporin, or a parenteral cephalosporin plus penicillin. Bites involving joints or tendons were excluded from this study. The results were dramatic, with 47% of the placebo group developing infection, while none of the subjects treated with antibiotics developed infection.2
- A larger, more recent trial attempted to address the question in patients with “low-risk” human bites by randomizing them to placebo or an oral cephalosporin plus penicillin. This trial excluded patients with bites to the hands, feet, or cartilaginous structures, and no patient in this trial had a bite wound that penetrated deep to the epidermis. The rate of infection in this study was much lower, with only one patient in the placebo group becoming infected. There was no statistically significant difference compared to the group treated with antibiotics.3
- A large, retrospective series examining human bite wounds in children found that none of the bites manifesting as abrasions became infected, while the rate of infection was much higher in bite wounds that caused punctures or lacerations.4
- From these data, one can conclude that it is probably efficacious to treat acute, non-infected human bite wounds with antibiotics if the wound involves the hands, feet, cartilaginous structures, or is deeper than the epidermal layer. In other words, prophylax all human bite wounds except for those manifesting as superficial abrasions in locations other than the hands, ears, and nose.
- Special cases
- Closed-fist injuries: An underlying fracture dictates inpatient treatment under certain circumstances. After appropriate anesthesia, explore the wound for joint space violation or tendon injury. Involvement of the joint space indicates admission. Consider patients with tendon injuries, which usually are present, for admission. Proper wound assessment includes using a tourniquet and extending the wound as needed to improve visualization. Provide outpatient treatment of these wounds (careful wound cleansing, antibiotic coverage, bulky dressing or splint, elevation) only in consultation with hand or orthopedic service. Early, mandatory follow-up care is essential.
- Chomping injuries: Treat non-infected wounds that appear to violate the tendon apparatus in the same manner as non-infected closed-fist injuries.
- Puncture wounds: These most commonly are encountered about the head. Such wounds are difficult to clean adequately unless extended to allow for effective irrigation. Even in the absence of infection, such wounds are best left open and closed secondarily, if cosmetically necessary.
- Bites to the ear or nose: When associated with tissue loss, these wounds require consultation with plastic surgery or ear, nose, and throat (ENT) service. Seeking consult for a bite that violates cartilage in these areas also is prudent because of poor blood supply to cartilage and difficulties in treating chondritis.
The infected human bite wound
- The current recommendations from the Infectious Disease Society of America (IDSA) call for the use of amoxicillin/clavulanate or ampicillin/sulbactam. TMP/SMX plus clindamycin is an acceptable alternative in the penicillin-allergic patient.5
- Infected closed-fist injuries are a special case because of the deep nature of these infections and relatively poor vascular supply to the tendons and other connective tissue. Admitting patients for intravenous (IV) antibiotic therapy is generally considered appropriate is these cases. Surgical debridement and drainage also may be necessary.
Other considerations
- HIV transmission has been noted only rarely after a human bite. Exposure to saliva alone is not considered a risk factor for HIV (or hepatitis) transmission. Transmission requires HIV-infected blood mixed in the saliva of the biter and a skin break on the victim. The reverse consideration also is important in that blood drawn from an HIV-infected victim would come in contact with the mucous membranes of the biter. A 2005 Centers for Disease Control and Prevention recommendation states that postexposure prophylaxis with a 28-day course of highly active antiretroviral therapy (HAART) should be used in either of these 2 scenarios.6
Consultations
- In general, consult hand and/or orthopedic service for infected human bites of the hand and those involving a fracture, joint space violation, or significant tendon injury. Consider consultation or agreed-upon protocols for other human bites to the hand.
- Consult plastic surgery or ENT service for significant injuries to the special structures about the face and for wounds involving significant tissue loss.
Medication
The only drug therapy of significance in human bites is antibiotic treatment. Bacterial flora include that of the mouth and skin. Theoretically, penicillin treats oral pathogens and may suffice for prophylactic treatment as Staphylococcus species probably only infect bite wounds secondarily.
Once a human bite is infected, beta-lactamase–producing staphylococci must be addressed. Eikenella corrodens may not be covered by first-generation cephalosporins. Additionally, Eikenella species are resistant to clindamycin, penicillinase-resistant semisynthetic penicillins, and metronidazole. A broad-spectrum antibiotic, rather than combination therapy, is the usual choice for infected bite wounds. An in vitro study of 50 infected human bites by Talan et al indicated that amoxicillin-clavulanic acid and moxifloxacin demonstrated excellent activity against common isolates.7
Antibiotics
Therapy must cover all likely pathogens in the context of the clinical setting.
Amoxicillin/clavulanate (Augmentin)
Drug combination that extends antibiotic spectrum of this penicillin to include bacteria normally resistant to beta-lactam antibiotics. DOC for noninfected human bite wounds. Dosing is based on amoxicillin component. Indicated for skin and skin structure infections caused by beta-lactamase-producing strains of Staphylococcus aureus.
Adult
875 mg PO bid for 5 d
Pediatric
45 mg/kg/d PO divided q12h
Risk of bleeding increases when coadministered with warfarin or heparin, possibly because of additive effects
Documented hypersensitivity
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Use may precipitate pseudomembranous colitis;
give for minimum of 10 d to eliminate organism and prevent sequelae (endocarditis, rheumatic fever); following treatment, perform cultures to confirm eradication of streptococci
Ampicillin/sulbactam sodium (Unasyn)
Drug combination that uses beta-lactamase inhibitor with ampicillin; covers skin, enteric flora, and anaerobes. DOC for infected bites.
Adult
1.5 (1 g ampicillin + 0.5 g sulbactam) to 3 g (2 g ampicillin + 1 g sulbactam) IV q6h; not to exceed 4 g/d sulbactam or 8 g/d ampicillin
Pediatric
<12 years: Not established
Probenecid and disulfiram elevate ampicillin levels; allopurinol decreases ampicillin effects and has additive effects on ampicillin rash; may decrease effects of oral contraceptives
Documented hypersensitivity
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Adjust dose in renal failure; evaluate rash and differentiate from hypersensitivity reaction
Cefoxitin (Mefoxin)
Alternative drug for infected bites; second-generation cephalosporin indicated for management of infections caused by susceptible gram-positive cocci and gram-negative rods. Many infections that are caused by gram-negative bacteria and are resistant to some cephalosporins and penicillins respond to cefoxitin.
Adult
2 g IV q8h
Pediatric
>3 months: 80-160 mg/kg/d IV divided q4-6h
Probenecid may increase effects; coadministration with aminoglycosides or furosemide may increase nephrotoxicity (closely monitor renal function)
Documented hypersensitivity
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Bacterial or fungal overgrowth of nonsusceptible organisms may occur with prolonged use or repeated treatment; caution in patients with previously diagnosed colitis
Moxifloxacin (Avelox)
Inhibits the A subunits of DNA gyrase, resulting in inhibition of bacterial DNA replication and transcription.
Adult
400 mg PO/IV qd
Pediatric
<18 years: Not recommended
>18 years: Administer as in adults
Antacids and electrolyte supplements reduce absorption; loop diuretics, probenecid, and cimetidine increase serum levels; NSAIDs enhance CNS stimulating effect; may increase toxicity of theophylline, caffeine, cyclosporine, and digoxin (monitor digoxin levels); may increase effects of anticoagulants (monitor PT); ferrous sulfate decreases bioavailability (administer moxifloxacin 4 h prior or 8 h following ferrous sulfate); coadministration with drugs that prolong QTc interval (quinidine, procainamide, amiodarone, sotalol, erythromycin, tricyclic antidepressants) increase risk of life-threatening arrhythmia
Documented hypersensitivity; known Q-T prolongation; concurrent administration of drugs that cause Q-T prolongation
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
In prolonged therapy, perform periodic evaluations of organ system functions (eg, renal, hepatic, hematopoietic); superinfections may occur with prolonged or repeated antibiotic therapy; fluoroquinolones have induced seizures in CNS disorders and caused tendinitis or tendon rupture
Immunizing agents
These agents are used to immunize patients against tetanus.
Tetanus immune globulin (Hyper-Tet)
Used for passive immunization of any person with a wound that may be contaminated with tetanus spores.
Adult
Prophylaxis: 250-500 U IM in opposite extremity to tetanus toxoid lesion
Clinical tetanus: 3000-10,000 U IM
Pediatric
Prophylaxis: 250 U IM in opposite extremity to tetanus toxoid
Clinical tetanus: 3000-10,000 U IM
None reported
Since antibodies in globulin preparation may interfere with immune response to vaccination, do not administer within 3 mo of live-virus immune globulin administration; may be necessary to revaccinate persons who received immune globulin shortly after live-virus vaccination
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Persons with isolated IgA deficiency have potential for developing antibodies to IgA and may have anaphylactic reactions to subsequent administration of blood products that contain IgA; do not perform skin testing since intradermal injection of concentrated gamma globulin may cause localized area of inflammation and can be misinterpreted, causing medication to be withheld from a patient not allergic to this material; true allergic responses to human gamma globulin given in prescribed IM manner are extremely rare; do not admix with other medications since usually incompatible
More on Bites, Human |
| Overview: Bites, Human |
| Differential Diagnoses & Workup: Bites, Human |
 Treatment & Medication: Bites, Human |
| Follow-up: Bites, Human |
| References |
| Further Reading |
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References
Harrison M. A 4-year review of human bite injuries presenting to emergency medicine and proposed evidence-based guidelines. Injury. Jan 31 2009;[Medline].
Zubowicz VN, Gravier M. Management of early human bites of the hand: a prospective randomized study. Plast Reconstr Surg. Jul 1991;88(1):111-4. [Medline].
Broder J, Jerrard D, Olshaker J, Witting M. Low risk of infection in selected human bites treated without antibiotics. Am J Emerg Med. Jan 2004;22(1):10-3. [Medline].
Baker MD, Moore SE. Human bites in children. A six-year experience. Am J Dis Child. Dec 1987;141(12):1285-90. [Medline].
Stevens DL, Bisno AL, Chambers HF, Everett ED, Dellinger P, Goldstein EJ. Practice guidelines for the diagnosis and management of skin and soft-tissue infections. Clin Infect Dis. Nov 15 2005;41(10):1373-406. [Medline].
Smith DK, Grohskopf LA, Black RJ, et al. Antiretroviral postexposure prophylaxis after sexual, injection-drug use, or other nonoccupational exposure to HIV in the United States: recommendations from the U.S. Department of Health and Human Services. MMWR Recomm Rep. Jan 21 2005;54(RR-2):1-20. [Medline].
Talan DA, Abrahamian FM, Moran GJ, et al. Clinical presentation and bacteriologic analysis of infected human bites in patients presenting to emergency departments. Clin Infect Dis. Dec 1 2003;37(11):1481-9. [Medline].
Bunzli WF, Wright DH, Hoang AT, et al. Current management of human bites. Pharmacotherapy. Mar-Apr 1998;18(2):227-34. [Medline].
Chen E, Hornig S, Shepherd SM, Hollander JE. Primary closure of mammalian bites. Acad Emerg Med. Feb 2000;7(2):157-61. [Medline].
Donkor P, Bankas DO. A study of primary closure of human bite injuries to the face. J Oral Maxillofac Surg. May 1997;55(5):479-81; discussion 481-2. [Medline].
Gilbert DN, Moellering RC, Sande MA. Human bites. In: The Sanford Guide to Antimicrobial Therapy. 30th ed. Antimicrobial Therapy Inc; 2000:37.
Kelly IP, Cunney RJ, Smyth EG, Colville J. The management of human bite injuries of the hand. Injury. Sep 1996;27(7):481-4. [Medline].
Lindsey D, Christopher M, Hollenbach J, et al. Natural course of the human bite wound: incidence of infection and complications in 434 bites and 803 lacerations in the same group of patients. J Trauma. Jan 1987;27(1):45-8. [Medline].
Miura I, Ohshima A, Takahashi N, et al. A new non-random chromosomal translocation t(3;6)(q27;p21.3) associated with BCL6 rearrangement in two patients with non-Hodgkin's lymphoma. Int J Hematol. Oct 1996;64(3-4):249-56. [Medline].
Pretty IA, Anderson GS, Sweet DJ. Human bites and the risk of human immunodeficiency virus transmission. Am J Forensic Med Pathol. Sep 1999;20(3):232-9. [Medline].
Schweich P, Fleisher G. Human bites in children. Pediatr Emerg Care. Jun 1985;1(2):51-3. [Medline].
Smith PF, Meadowcroft AM, May DB. Treating mammalian bite wounds. J Clin Pharm Ther. Apr 2000;25(2):85-99. [Medline].
Turner TW. Evidence-based emergency medicine/systematic review abstract. Do mammalian bites require antibiotic prophylaxis?. Ann Emerg Med. Sep 2004;44(3):274-6. [Medline].
Further Reading
Clinical guidelines
Management of human bite wounds. University of Texas, School of Nursing, Family Nurse Practitioner Program. Management of human bite wounds. Austin (TX): University of Texas, School of Nursing; 2007 May. 22 p.
Antiretroviral postexposure prophylaxis after sexual, injection-drug use, or other nonoccupational exposure to HIV in the United States: recommendations from the U.S. Department of Health and Human Services. Smith DK, Grohskopf LA, Black RJ, Auerbach JD, Veronese F, Struble KA, Cheever L, Johnson M, Paxton LA, Onorato IM, Greenberg AE. Antiretroviral postexposure prophylaxis after sexual, injection-drug use, or other nonoccupational exposure to HIV in the United States: recommendations from the U.S. Department of Health and Human Services. MMWR Recomm Rep 2005 Jan 21;54(RR-2):1-26. [126 references] PubMed
Practice guidelines for the diagnosis and management of skin and soft-tissue infections. Stevens DL, Bisno AL, Chambers HF, Everett ED, Dellinger P, Goldstein EJ, Gorbach SL, Hirschmann JV, Kaplan EL, Montoya JG, Wade JC. Practice guidelines for the diagnosis and management of skin and soft-tissue infections. Clin Infect Dis 2005 Nov 15;41(10):1373-406. [236 references] PubMed
Keywords
human bites, human bite wound, closed-fist injury, chomping injury, puncture-type wound, infected human bite wounds, bite wounds, bite injury
