Community-acquired pneumonia caused by macrolide-resistant Mycoplasma pneumoniae in adults.

We herein describe a case of community-acquired pneumonia caused by macrolide-resistant Mycoplasma pneumoniae (MRMP) in an adult who responded poorly to macrolide antibiotics, progressively deteriorated to acute respiratory failure and then responded effectively to a fluoroquinolone. In a series of 14 patients with M. pneumoniae pneumonia, 11 were infected with MRMP. In seven of the eight cases of MRMP initially treated with macrolides, the patients did not improve, and a marked improvement was observed only after the antibiotic regimen was modified to include fluoroquinolones or tetracyclines. Nationwide surveillance should provide important information regarding the prevalence and empirical treatment of MRMP infection in adults.