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

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.

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.

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).

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.