Culture-based antibiotic susceptibility testing for infection: a systematic review.

Background: Primary antibiotic resistance in () strains is increasing worldwide, affecting therapy success. The use of therapies tailored on susceptibility pre-testing at culture has been proposed, but data are still conflicting.

Method: We performed a systematic review to evaluate the role of a culture-based therapeutic approach for treatment, taking into account the sensitivity of culture and the success rates achieved with tailored therapies in different therapeutic steps.

Results: We analyzed data from 51 studies. Overall, strains were isolated in 80.7% of 7889 patients, the success rates being 78.1%, 77.5%, 86.3% and 86.6%, before first-, second-, third-line or more therapies, respectively. In comparative studies, the infection was cured in 89.9% of 2052 patients treated with tailored therapies, and in 77.6% of 2516 patients receiving empiric therapy (P<0.001). However, in the subanalysis, the tailored approach achieved optimal eradication rates (>90%) only when it was applied before first- and second-line therapies, but not before third-line or more attempts (<80%). Moreover, no significant difference emerged between the 2 approaches when data from only the most recent (last 5 years) studies were considered, as well as in those performed in Western populations.

Conclusions: The attempt to achieve antibiotic susceptibility testing before treatment failed in 20% of infected patients managed in dedicated laboratories. Culture-tailored therapies administered after 2 or more therapies achieved suboptimal eradication rates. The role of bacterial culture in patients whose therapeutic management failed to eradicate probably needs to be corroborated by further data.