Initial treatment failure in patients with complicated skin and skin structure infections.

BACKGROUND: Consequences of initial antibiotic failure in patients hospitalized for complicated skin and skin-structure infections (cSSSI) are not well understood.
METHODS: Using data from >100 hospitals in the United States, we identified all adults hospitalized for cSSSI between January 1, 2000 and June 30, 2009. We defined "initial therapy" as all parenteral antibiotics administered <24 h of admission, and such therapy was assumed to have failed if the patient (1) received new antibiotic(s) subsequently (excluding similar/narrower spectrum antibiotics or those begun at discharge), or (2) underwent drainage/debridement/amputation>72 h after admission. We limited attention to the 40 most commonly used antibiotic regimens in 2009. We compared clinical and economic outcomes of patients who experienced initial treatment failure and those who did not.
RESULTS: The rate of initial treatment failure was 16.6% in acute infections (n=13,498), 34.1% in chronic/ulcerative infections (n=1,116), and 26.7% in surgical site infections (SSIs) (n=2,929). Treatment failure was associated with 4.1-7.3 additional days in the hospital and $11,995-$23,655 in additional inpatient charges; the case fatality rate was from 4- to 12-fold higher in patients who experienced treatment failure than in those who did not (all comparisons, p<0.01).
CONCLUSION: Initial treatment failure in patients hospitalized for cSSSI is associated with significantly worse clinical outcomes, longer hospital stays, and higher hospital charges than with successful initial treatment.