title: Clinical efficacy of macrolide antibiotics against genetically determined macrolide-resistant Mycoplasma pneumoniae pneumonia in paediatric patients.
abstract: OBJECTIVE
  Since 2000, the prevalence of macrolide-resistant (MR) Mycoplasma pneumoniae has increased among paediatric patients in Japan. To determine the efficacy of macrolides against MR M. pneumoniae pneumonia, microbiological and clinical efficacies were compared during the antibiotic treatment.
  
  
  METHODS
  Samples from a total of 30 children with M. pneumoniae pneumonia, as confirmed by PCR and serology, were analyzed. Primers for domain V of 23S rRNA were used, and DNA sequences of the PCR products were compared with the sequence of an M. pneumoniae reference strain.
  
  
  RESULTS
  Isolates from 21 patients demonstrated point mutations, and these patients were defined as MR. The remaining nine patients, whose isolates showed no point mutations, were categorized as control (macrolide-sensitive) patients. The number of M. pneumoniae in nasopharyngeal samples from the control group decreased rapidly 48 h after initiation of macrolide treatment and showed a close relationship with clinical outcome. In contrast, the number of M. pneumoniae 48 h after initiation of macrolide treatment were significantly higher in samples from MR patients than in samples from macrolide-sensitive patients. In 15 of 21 MR patients, fever persisted for more than 48 h after the initiation of macrolide treatment. When treatment was changed to minocycline, fever disappeared within 48 h in all these MR patients. There were no differences between MR patients who demonstrated a reduction in fever and those in whom fever persisted after 48 h of macrolide treatment.
  
  
  CONCLUSIONS
  The microbiological and clinical efficacies of macrolides for treating patients with MR M. pneumoniae pneumonia were low. These results show that macrolides are clearly less effective in patients with MR M. pneumoniae pneumonia.
authors.affiliation: Department of Pediatrics, Kawasaki Medical School, Okayama, Japan. nao@med.kawasaki-m.ac.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kawai
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Miyashita
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Aki
authors.initials: A
authors.lastname: Saitoh
authors.forename: Eisuke
authors.initials: E
authors.lastname: Kondoh
authors.forename: Hiroki
authors.initials: H
authors.lastname: Fujimoto
authors.forename: Hideto
authors.initials: H
authors.lastname: Teranishi
authors.forename: Mika
authors.initials: M
authors.lastname: Inoue
authors.forename: Tokio
authors.initials: T
authors.lastname: Wakabayashi
authors.forename: Hiroto
authors.initials: H
authors.lastname: Akaike
authors.forename: Satoko
authors.initials: S
authors.lastname: Ogita
authors.forename: Kozo
authors.initials: K
authors.lastname: Kawasaki
authors.forename: Kihei
authors.initials: K
authors.lastname: Terada
authors.forename: Fumio
authors.initials: F
authors.lastname: Kishi
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Ouchi
mesh_terms: D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000235:genetics*; D024881:Drug Resistance, Bacterial; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D018942:Macrolides / Q000627:therapeutic use*; D008297:Male; D009177:Mycoplasma pneumoniae / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D011019:Pneumonia, Mycoplasma / Q000188:drug therapy* / Q000382:microbiology; D017354:Point Mutation; D016133:Polymerase Chain Reaction / Q000379:methods; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D018942:Macrolides; D012338:RNA, Ribosomal, 23S