title: Emerging resistance to carbapenems in a tertiary care hospital in north India.
abstract: OBJECTIVE
  Carbapenems are beta-lactam antibiotics, presently considered as most potent agents for treating multi-drug resistant Gram-negative bacilli infections. In India carbapenems available for use are meropenem and imipenem, introduced recently. Resistance to these has been reported in a few bacteria especially Pseudomonas spp. We therefore retrospectively evaluated the antibiotic susceptibility pattern to these agents amongst various clinical isolates in a tertiary care hospital in north India.
  
  
  METHODS
  In this study Gram-negative bacterial pathogens isolated from clinical samples were tested for extended spectrum beta lactamase (ESBL) production. All ESBL positive bacteria were tested for meropenem and imipenem activity pattern using NCCLS guidelines. A total of 2626 consecutively isolated Gram-negative bacteria, which tested positive for ESBL production by the double disk diffusion method, were included.
  
  
  RESULTS
  The different bacteria isolated were Pseudomonas spp. 759, Acinetobacter spp. 676, Escherichia coli 569, Klebsiella spp. 343, Enterobacter spp. 150, Citrobacter spp. 57 and Proteus spp. 72. Overall resistance to meropenem was more (22.16%) than imipenem (17.32%). Maximum resistance was seen in Pseudomonas spp. M(R) 37.6 per cent, I(R) 30 per cent. In isolates from intensive care units (ICU) resistance to carbapenems was significantly higher than non-ICU patients.
  
  
  CONCLUSIONS
  Resistance to meropenem and imipenem was seen in various clinical isolates of Gram-negative ESBL-positive bacteria. There is a need to alarm our clinicians for judicious use of antibiotics.
authors.affiliation: Department of Microbiology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Ekta
authors.initials: E
authors.lastname: Gupta
authors.forename: Srujana
authors.initials: S
authors.lastname: Mohanty
authors.forename: Seema
authors.initials: S
authors.lastname: Sood
authors.forename: Benu
authors.initials: B
authors.lastname: Dhawan
authors.forename: Bimal K
authors.initials: BK
authors.lastname: Das
authors.forename: Arti
authors.initials: A
authors.lastname: Kapil
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006801:Humans; D015378:Imipenem / Q000494:pharmacology*; D000077731:Meropenem; D008826:Microbial Sensitivity Tests; D013845:Thienamycins / Q000494:pharmacology*; D001618:beta-Lactamases / Q000096:biosynthesis
chemical_list: D000900:Anti-Bacterial Agents; D013845:Thienamycins; D015378:Imipenem; D001618:beta-Lactamases; D000077731:Meropenem