Multilocus variable-number tandem-repeat analysis-confirmed emergence of a macrolide resistance-associated mutation in Mycoplasma pneumoniae during macrolide therapy for interstitial pneumonia in an immunocompromised child

A child with Job's syndrome was treated for pneumonia due to Mycoplasma pneumoniae. A mixed population of wild-type bacteria and an A2059G mutant was detected during josamycin treatment failure. The same multilocus variable-number tandem-repeat analysis (MLVA) type (MLVA type I) was isolated before and after treatment failure. The child recovered after ciprofloxacin treatment.