Variability of macrolide-resistant profile in complex pulmonary disease.

This single-center retrospective study aimed to analyze the variability of macrolide resistance (MR) in 68 patients with complex pulmonary disease. Among 25 patients treated without macrolides, 13 (52%) reverted to macrolide-susceptible (MS) profiles. Only one (2%) of 43 patients who continued macrolide treatment showed this change. We compared 30 MR isolates with recent specimens. Among them, seven shifted to MS (five attributed to clonally related strains; two resulting from reinfection or polyclonal infection).