title: Imipenem Resistant Pseudomonas aeruginosa: The fall of the final quarterback.
abstract: OBJECTIVE
  To isolate, determine the frequency, and study the demographic trends of MBL positive Pseudomonas aeruginosa from imipenem resistant isolates collected from clinical samples in a tertiary care hospital of Pakistan.
  
  
  METHODS
  In this cross sectional study a total of 230 strains of Pseudomonas were isolated from various clinical specimens on the basis of culture and biochemical tests. Imipenem resistant isolates were selected by Kirby Bauer Diffusion technique, followed by screening for MBL production by Imipenem EDTA Combined Disk Test. Demographic details of each patient were recorded on a separate questionnaire. Chi-Square goodness-of-fit test was computed to review the isolation of MBL positive isolates (P-value ≤ 0.05) in different specimen.
  
  
  RESULTS
  Out of 230 strains of P. aeruginosa 49.5% were imipenem resistant; MBL production was confirmed in 64.9% of the resistant isolates. Resistance to polymyxin B (12.5%) was notable. Majority of the MBL positive strains were isolated from patients aged between 20-39 years (45.9%) and the predominant source was pus (43.24%) which was found to be statistically significant (P-value=0.04). Outpatient departments (24.3%) and burn unit (21.6%) were the major places for resistant isolates.
  
  
  CONCLUSIONS
  MBL production is one of the major causes of IRPA. Increasing resistance to polymyxin B is grave. Due to acquisition of MBL strains MDR P. aeruginosa has become endemic in tertiary setups.
authors.affiliation: Nadya Ameen, MBBS. Department of Pharmacology, Ziauddin University, St-4B, Sharah-e-Ghalib Block6, Karachi-75600, Pakistan.
authors.forename: Nadya
authors.initials: N
authors.lastname: Ameen
authors.affiliation: Zahida Memon, MBBS, M.Phil, PhD. Department of Pharmacology, Ziauddin University, St-4B, Sharah-e-Ghalib Block6, Karachi-75600, Pakistan.
authors.forename: Zahida
authors.initials: Z
authors.lastname: Memon
authors.affiliation: Shehla Shaheen, MBBS, M.Phil. Department of Pharmacology, Ziauddin University, St-4B, Sharah-e-Ghalib Block6, Karachi-75600, Pakistan.
authors.forename: Shehla
authors.initials: S
authors.lastname: Shaheen
authors.affiliation: Ghulam Fatima, MBBS, MCPS, M.Phil Central Lab, Civil Hospital, Karachi, Pakistan.
authors.forename: Ghulam
authors.initials: G
authors.lastname: Fatima
authors.affiliation: Farah Ahmed, MBBS, MPH. Department of Community Health Sciences, Ziauddin University, Karachi, Pakistan.
authors.forename: Farah
authors.initials: F
authors.lastname: Ahmed
keywords: Imipenem-resistant Pseudomonas aeruginosa (IRPA); Metallo-beta-lactamases (MBL); combined disk test