Hospital acquired infections in a medical intensive care unit

Abstract

Objective: To determine the frequency of nosocomial infections and causative organisms in medical intensive care unit (ICU) patients and antimicrobial susceptibility pattern of the isolates.

Study design: A cross-sectional study.

Place and duration of study: The Holy Family Hospital, Rawalpindi, during the period of May 2007 to April 2008.

Methodology: Clinical samples from patients having any signs of site-specific infections or fever appearing anytime after 48 hours of admission into ICU were collected. The samples were cultured onto suitable culture media and bacterial isolates were identified using standard biochemical methods. Antimicrobial susceptibility testing to conventional and newer antibiotics was performed on Mueller Hinton agar using disc diffusion method. Frequency percentages were determined.

Results: Bacteria or Candida spp. were isolated from 269/440 (60.1%) samples. The most frequent site of infection was respiratory tract (47.95%) followed by urinary tract (25.3%). Pseudomonas (P.) aeruginosa, Klebsiella (K.) pneumoniae, Escherichia (E.) coli and Candida spp. were the commonest organisms. The isolation rate of Gram-positive bacteria was relatively low. Majority (> 50%) of the Gram-negative isolates were resistant to many of the antibiotics tested. Relatively low resistance was only observed against amikacin (21.3%) and imipenem (26.1%). Majority (> 60%) of Gram-negative isolates were resistant to cefotaxime, ceftriaxone and ceftazidime. The isolates showed high resistance to ofloxacin (65.9%) and ciprofloxacin (73.9%).

Conclusion: The high frequency of HAIs and antibiotic resistance rate, suggests that more strict infection control practices along with prescription of antibiotics after antibiotic susceptibility testing should be implemented to limit the emergence of antibiotic resistant organisms.