Risk factors for clinical failure in patients hospitalized with cellulitis and cutaneous abscess.

OBJECTIVE: The objective of this study was to evaluate clinical outcomes and risk factors associated with clinical failure in patients hospitalized with cellulitis with or without abscess.

METHODS: We performed a retrospective cohort study among adults admitted for cellulitis/cutaneous abscess from July 1, 2009 through June 30, 2010. Binary univariate and multivariate logistic regression analyses were performed to identify risk factors for clinical failure among evaluable patients.

RESULTS: A total of 210 cases met inclusion criteria. Among 106 evaluable cases, clinical failure occurred in 34 (32.1%) patients. Weight over 100 kg (Odds ratio [OR] = 5.20, P = 0.01), body mass index (BMI) ≥40 (OR 4.10, P = 0.02), inadequate empiric antibiotic therapy (OR = 9.25, P < 0.01), recent antimicrobial therapy (OR = 2.98, P = 0.03), and lower end of antibiotic dosing per treatment guidelines upon discharge (OR = 3.64, P < 0.01) were independent risk factors for clinical failure. Further subgroup analysis demonstrated that morbidly obese patients were at higher risk for clinical failure if they were discharged on a low oral dose of clindamycin or trimethoprim/sulfamethoxazole (P = 0.002).

CONCLUSION: Inappropriate antimicrobial selection and dosing may adversely affect clinical outcomes among patients with cellulitis/cutaneous abscess. Obese individuals may be at particular risk for clinical failure secondary to inadequate dosing of antimicrobial therapy.