878. Risk Factors for Clinical Failure in Outpatients Treated for Cellulitis and Cutaneous Abscess
Session: Poster Abstract Session: Bone, Joint, and Soft Tissue Infection
Friday, October 19, 2012
Room: SDCC Poster Hall F-H
  • ESZhu_IDSA_2012_SSTI_Poster.pdf (2.6 MB)
  • Background: Cellulitis and cutaneous abscesses are skin and soft tissue infections (SSTIs) usually accompanied by mild systemic symptoms and treated with oral antibiotics.  While there is existing literature to describe risk factors for developing SSTIs, there is limited insight into the risk factors associated with clinical failure.

    Methods: This was a retrospective, single-center cohort study that evaluated patients with cellulitis (with or without abscess) initially diagnosed and treated in the outpatient setting from August 1, 2010 - July 30, 2011.  Clinical failure was defined as repeat incision and drainage (I&D), antimicrobial change, extension of treatment duration, recurrence, or SSTI- related emergency department or hospital admission.

    Results: 120 patients were screened of which 94 met inclusion criteria for further evaluation.  Overall, 27 (28.7%) patients in the study experienced clinical failure.  Failure rates were higher with recurrent episodes (48% vs 23%) and was found to be independently associated with clinical failure (Odds ratio [OR] 2.99, p=0.023).  I&D (OR 3.98, p = 0.004) and required wound care (OR 3.16, p=0.015) were associated with clinical failure upon univariate analysis.  Co-trimoxazole was the commonly prescribed antimicrobial agent (25/94).  Upon further subgroup analysis of patients receiving co-trimoxazole, 47% of patients received low dosing of co-trimoxazole (< 5mg/kg/day).

    Conclusion: Recurrent SSTI, I&D, and wound care are factors associated with clinical failure of patients treated for cellulitis and/or cutaneous abscess in the outpatient setting.  Current literature supports I&D as the mainstay of effective therapy for cutaneous abscess, but our study found higher associated failure rates.   Inadequate I&D will need to be explored as a possible explanation for our results.  Also, further study is needed to determine optimal dosing of co-trimoxazole to treat cellulitis.

    Elizabeth S. Zhu, Pharm.D., Pharmacy, University of Cailfornia, Davis Medical Center, Sacramento, CA, Jenana Halilovic, Pharm.D., BCPS, Thomas J. Long School of Pharmacy and Health Sciences, University of the Pacific, Stockton, CA, Brett Heintz, PharmD, BCPS-ID, AAHIVE, School of Pharmacy, University of California, San Francisco, San Francisco, CA and Cinda Christensen, PharmD, BCPS-ID, Pharmacy Services, University of California, Davis Medical Center, Sacramento, CA


    E. S. Zhu, None

    J. Halilovic, None

    B. Heintz, None

    C. Christensen, None

    Findings in the abstracts are embargoed until 12:01 a.m. PST, Oct. 17th with the exception of research findings presented at the IDWeek press conferences.