Weight-Based Dosing of Clindamycin and TMP/SMX Improves Cellulitis Outcomes

Patients hospitalized with cellulitis should receive weight-based dosing of clindamycin and trimethoprim/sulfamethoxazole (TMP/SMX) to reduce the risk for clinical failure, according to a multicenter retrospective cohort study published in the Journal of Infection.

Researchers identified 208 people who were hospitalized for cellulitis, received at least 7 days of antimicrobial therapy, and were discharged on either oral clindamycin or TMP/SMX. Of these, 120 patients received inadequate dosing of clindamycin (<10 mg/kg/d) or TMP/SMX (<5 mg TMP/kg/d) and 88 patients received adequate dosing (n=73, clindamycin; n=15, TMP/SMX). A univariate analysis revealed several factors associated with inadequate dosing, including increased body weight and body mass index.

Patients receiving inadequate dosing experienced a clinical failure rate of 30%, while the rate was only 17% in patients receiving adequate therapy (P =.032). 

A univariate analysis found that both longer hospitalization (odds ratio [OR]=2.96, P =.046) and inadequate dosing (OR=2.09, P =.034) were factors in clinical failure, whereas a multivariate analysis demonstrated that inadequate dosing (OR=2.01, P =.032) was independently associated with clinical failure.   

Limitations of the study include its retrospective design and that the guidelines for adequate dosing of clindamycin and TMP/SMX in cellulitis are not well defined. 

The authors believe this is the first study to evaluate clinical failure using weight-based dosing of oral clindamycin and TMP/SMX in patients hospitalized for cellulitis and concluded that, “Providers should consider weight-based dosing of both clindamycin and TMP/SMX to optimize tissue penetration and reduce the risk of clinical failure.”  

Reference

Cox KK, Alexander B, Livorsi DJ, Hentz BH. Clinical outcomes in patients hospitalized with cellulitis treated with oral clindamycin and trimethoprim/sulfamethoxazole: the role of weight-based dosing [published online September 11, 2017]. J Infect. doi:10.1016/j.jinf.2017.09.009