DISTRIBUTION OF KLEBSIELLA PNEUMONIAE ISOLATED FROM CLINICAL SPECIMENS OF INTENSIVE CARE UNIT PATIENTS AND THEIR ANTIMICROBIAL SUSCEPTIBILITY PROFILE: A RETROSPECTIVE STUDY FROM A TERTIARY CARE HOSPITAL IN GUJARAT

Abstract

Background: Klebsiella pneumoniae is a leading cause of healthcare-associated infection in intensive care units (ICUs),and the spread of extended-spectrum β-lactamase- and carbapenemase-producing strains has steadily narrowed the therapeutic options. Local surveillance of its distribution and susceptibility pattern is essential for empirical prescribing and antibiotic policy. Objective: To determine the distribution of K. pneumoniae isolated from clinical specimens of ICU patients and to describe its antimicrobial susceptibility profile. Methods: A retrospective, record-based cross-sectional study was conducted in the Department of Microbiology of a tertiary care teaching hospital in Gujarat. All clinical specimens received from ICU patients between July 2025 and July 2026 were reviewed. Specimens had been processed by standard methods, including Gram staining and culture on blood, chocolate and MacConkey agar, with identification by conventional biochemical tests. Antimicrobial susceptibility had been determined by the modified Kirby–Bauer disc diffusion method on Mueller–Hinton agar and interpreted according to Clinical and Laboratory Standards Institute (CLSI) criteria. Demographic, specimen and susceptibility data were retrieved from laboratory records and the WHONET database and summarised descriptively. Results: Of 2,730 ICU specimens, 475 (17.4%) yielded bacterial growth, and K. pneumoniae accounted for 98 (20.6%) of the culture-positive specimens. Fifty-six isolates (57.1%) came from men and 42 (42.9%) from women; the 56–75-year age group contributed the most isolates (39; 39.8%), followed by the 36–55-year group (23; 23.5%). Lower respiratory tract specimens accounted for 41 isolates (41.8%), wound swabs for 27 (27.6%), urine for 11 (11.2%) and blood for 7 (7.1%). Susceptibility was highest to tobramycin (94%), amikacin (90%), meropenem (89%), netilmicin (84%) and gentamicin (82%), and lowest to amoxicillin-clavulanate (16%), cefazolin (21%), cefuroxime (32%), ciprofloxacin (42%) and cefoperazone and ceftazidime (48% each). Conclusion: K. pneumoniae was responsible for one in five culture-positive ICU specimens, chiefly from older men and from the respiratory tract. Susceptibility to aminoglycosides and meropenem was well preserved, whereas most cephalosporins, amoxicillin-clavulanate and fluoroquinolones performed poorly. Continued surveillance, susceptibility-guided prescribing and strict infection-control practice are needed to contain resistant K. pneumoniae in the ICU.