Eradication of nasopharyngeal carriage of penicillin-non-susceptible Streptococcus pneumoniae--is it possible?

Background: The South Swedish Pneumococcal Intervention Project (SSPIP) was started in 1995 with the aim of limiting the spread of penicillin-non-susceptible pneumococci (PNSP) in Skane County, Sweden. As part of the SSPIP, eradication therapy with rifampicin in combination with 1 more antibiotic was considered on a social indication after prolonged carriage of 2-3 months. Methods: In this retrospective study, 125 medical records were analyzed. Children aged 0-10 y referred for eradication therapy in Malmo and Lund, due to a prolonged nasopharyngeal carriage of PNSP with a penicillin G minimum inhibitory concentration of >= 0.5 mg/l, between the y 1997 and 2011 were included. Two consecutive negative cultures, with the second one no shorter than 7 days after treatment completion, were required for the carriage to be considered eradicated. Results: Out of 125 children, 71 received treatment with rifampicin in combination with amoxicillin (n = 44), erythromycin (n = 22), or clindamycin (n = 5) for 7 days. Eradication treatment was successful in 91.5% of the children. Six children (8.5%) had treatment failure with amoxicillin and rifampicin; 3 were found by late follow-up. There was a trend towards a better outcome with erythromycin and clindamycin combinations in comparison to amoxicillin. Conclusions: Eradication therapy was successful, but a proper follow-up is essential.