title: Treatment and Outcome of Carbapenem-Resistant Gram-Negative Bacilli Blood-Stream Infections in a Tertiary Care Hospital.
abstract: BACKGROUND
  Infections caused by carbapenem-resistant bacteria constitute a major challenge for current medical practice.
  
  
  OBJECTIVE
  To describe treatment and outcome of carbapenem-resistant Gram-negative bacilli (GNB) blood-stream infection (BSI) caused by these organisms at a tertiary care hospital in Mumbai.
  
  
  METHODS
  Carbapenem-resistant isolates from blood cultures were collected from January 2013 to April 2013. Identification and antimicrobial susceptibility testing were performed using Vitek 2 analyzer (Biomerieux Ltd.). Carbapenemase production was detected by modified Hodge's test (MHT). Patient's medical history, treatment and co-morbid conditions were noted. Outcomes of BSIs were evaluated.
  
  
  RESULTS
  Forty-two isolates of carbapenem-resistant GNB isolated from BSIs were Enterobacteriaceae spp. (19), Acinetobacter baumannii (15), and Pseudomonas aeruginosa (8). Colistin had maximum in vitro activity with 97% against Enterobacteriaceae, 100% against Acinetobacter, and 100% activity against Pseudomonas aeruginosa isolates. Positivity of MHT was 92.9%. Outcome of colistin mono and combination therapy was comparable with 83% and 79%, respectively. Outcome of colistin and carbapenem combination therapy was found to be 100 percent.
  
  
  CONCLUSIONS
  High incidences of bacteremia by carbapenem-resistant GNB including Enterobacteriaceae is a worrisome trend. Treatment options are compromised and only available option is colistin which has its own limitation. Colistin monotherapy may be non-inferior compared to combination therapy for treating BSIs caused by isolates with minimum inhibitory concentration (MIC) for colistin as ≤0.5 mg/l. Combined use of the colistin and carbapenem may provide good therapeutic options for BSI caused by carbapenem-resistant GNB and warrants further investigations.
authors.forename: Pooja G
authors.initials: PG
authors.lastname: Shah
authors.forename: Sweta R
authors.initials: SR
authors.lastname: Shah
mesh_terms: D040981:Acinetobacter baumannii; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016470:Bacteremia / Q000188:drug therapy* / Q000382:microbiology*; D015780:Carbapenems; D002648:Child; D002675:Child, Preschool; D003091:Colistin / Q000627:therapeutic use; D004755:Enterobacteriaceae; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology*; D006801:Humans; D007194:India; D007223:Infant; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011550:Pseudomonas aeruginosa; D062606:Tertiary Care Centers; D016896:Treatment Outcome; D055815:Young Adult; D018440:beta-Lactam Resistance
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D003091:Colistin