Abstract
Klebsiella pneumoniae
is a leading cause of hospital‐acquired infections, particularly in intensive care units (ICUs), where multidrug‐resistant (MDR) and hypervirulent strains represent major therapeutic challenges. This study investigated the phenotypic and molecular features of isolates recovered from ICU patients and the hospital environment in Benghazi, Libya. Antimicrobial susceptibility was determined using disk diffusion and the colistin broth disk elution method. Extended‐spectrum‐
β
‐lactamase (ESBL) and carbapenemase production were assessed phenotypically and confirmed by PCR and sequencing, whereas clonal relatedness was analyzed through OmpK36 typing. Hypervirulence was evaluated using the string test, PCR detection of virulence genes, and biofilm formation assays. A total of 56 isolates (46 clinical and 10 environmental) were included. All isolates were resistant to ceftriaxone, with high resistance rates to ceftazidime, cefotaxime, carbapenems, ciprofloxacin, and gentamicin. ESBL production was observed in 76% of clinical and 80% of environmental isolates, and 95% of all isolates were classified as MDR. A significant proportion of
K. pneumoniae
isolates (
n
= 15) exhibited resistance to colistin in the absence of detectable
mcr
genes. Strong and moderate biofilm production was detected in 30.4% and 17.9% of isolates, respectively. The
bla
NDM-5
was prevalent among clinical (45/46; 97.8%) and environmental (9/10; 90%) isolates. Similarly,
bla
CTX-M-15
was detected in 35/46 (76%) clinical isolates and 8/10 (80%) environmental isolates, whereas
bla
OXA-48
was detected in 26/46 (56.5%) clinical and 10/10 (100%) environmental isolates. A potentially hypervirulent phenotype was observed in 17.8% of the isolates, associated with the virulence genes
iuc
A,
iut
A, and
peg
‐344. OmpK36 Groups C and D predominated. These results highlight the alarming spread of MDR and hypervirulent strains in ICUs and underscore the need for reinforced infection control strategies.