title: Rifampicin/imipenem combination in the treatment of carbapenem-resistant Acinetobacter baumannii infections.
abstract: BACKGROUND
  In the setting of a large endemic of Acinetobacter baumannii infections, treatment of those due to carbapenem-resistant strains, susceptible only to colistin, has become a major problem in our hospital during the past years. Successful results have been reported using colistin, but clinical experience with this antibiotic is limited. In our experimental studies using these strains in a mouse pneumonia model, the best results were observed with a combination of rifampicin and imipenem.
  
  
  METHODS
  From July 2000 to September 2001, we performed a pilot study with patients suffering from serious infections due to carbapenem-resistant A. baumannii. Patients were treated with a rifampicin/imipenem combination and followed up prospectively. Cultures were repeated during and after treatment, and in vitro activity of rifampicin was monitored. Genotyping of these strains was performed by means of PFGE.
  
  
  RESULTS
  Ten patients were selected: four with ventilator-associated pneumonia, and six with other infections (one catheter-related bacteraemia, five surgical infections). Three patients died, two of whom were considered therapeutic failures. In five of the seven patients who were cured, other procedures were also performed such as surgical drainage or catheter removal. In vitro development of high resistance to rifampicin was shown in seven (70%). PFGE demonstrated that initial isolates and high-resistant strains belonged to the same clones.
  
  
  CONCLUSIONS
  The results of our study argue against the use of a rifampicin/imipenem combination for the treatment of carbapenem-resistant A. baumannii infections. However, combinations of rifampicin with other antibiotics merit further studies.
authors.affiliation: Infectious Disease Service, Hospital de Bellvitge, University of Barcelona C/Feixa Llarga s/n 08907, L'Hospitalet de Llobregat, Barcelona, Spain. msaballs@csub.scs.es
authors.forename: Mireia
authors.initials: M
authors.lastname: Saballs
authors.forename: Miquel
authors.initials: M
authors.lastname: Pujol
authors.forename: Fe
authors.initials: F
authors.lastname: Tubau
authors.forename: Carmen
authors.initials: C
authors.lastname: Peña
authors.forename: Abelardo
authors.initials: A
authors.lastname: Montero
authors.forename: M Angeles
authors.initials: MA
authors.lastname: Domínguez
authors.forename: Francesc
authors.initials: F
authors.lastname: Gudiol
authors.forename: Javier
authors.initials: J
authors.lastname: Ariza
mesh_terms: D000151:Acinetobacter Infections / Q000188:drug therapy* / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000302:isolation & purification; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D015780:Carbapenems / Q000494:pharmacology*; D004334:Drug Administration Schedule; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D015378:Imipenem / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D007262:Infusions, Intravenous; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012293:Rifampin / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D015378:Imipenem; D012293:Rifampin