Eradication of respiratory tract MRSA at a large adult cystic fibrosis centre.

INTRODUCTION: The prevalence of MRSA in patients with CF is increasing. There is no consensus as to the optimum treatment. METHOD: An observational cohort study of all patients with MRSA positive sputum, 2007-2012. All eradication attempts with subsequent culture results were reviewed. Single vs dual antibiotic regimens were compared for both new and chronic infections. RESULTS: 37 patients (median FEV1 58.7 (27.6-111.5)% predicted) were identified, of which 67.6% (n = 25) had newly acquired MRSA. Compared with single regimens, a high proportion of dual regimens achieved MRSA eradication (84.6% vs 50%; p = 0.1) for new infections. Rifampicin/Fusidic acid was associated with high success rates (100% vs 60% for other dual regimens (p = 0.13)). Compared with new infections, chronic MRSA was much less likely to be eradicated (18.2%, p = 0.01). CONCLUSION: Combined antibiotic therapy, particularly Rifampicin/Fusidic acid, is a well-tolerated and effective means of eradicating MRSA in patients with cystic fibrosis.