Multidrug-resistant Klebsiella pneumoniae in oncology intensive care units: selected genetic markers and clinical predictors.

BACKGROUND

Multidrug-resistant (MDR) Klebsiella pneumoniae poses a critical threat in oncology intensive care units (ICUs), particularly in low- and middle-income countries like Egypt, where immunocompromised patients are at high risk from invasive procedures. This study aimed to characterize antimicrobial resistance patterns and molecular features of MDR K. pneumoniae isolates and to explore clinical and genetic markers associated with resistance burden.

METHODS

Fifty K. pneumoniae isolates were recovered from cancer patients at Shefa Al Orman Oncology Hospital (Luxor, Egypt). Susceptibility testing was performed using VITEK® 2. Resistance genes (OmpK35, QnrB, AcrAB, OqxA, and Sul2) were detected via PCR. Resistance burden was quantified as a resistance score (R-score) and analyzed against clinical and genetic variables using non-parametric tests and regression models.

RESULTS

All isolates (100%) were resistant to β-lactams. High resistance rates were observed for carbapenems (78-84%), fluoroquinolones (84%), aminoglycosides (76-80%), and trimethoprim-sulfamethoxazole (86%), while tetracycline (40%) and tigecycline (10%) showed lower resistance. Genetic analysis revealed Sul2 (100%), OmpK35 (94%), OqxA (92%), QnrB (90%), and AcrAB (68%). Prior hospitalization and antibiotic use within three months were the only independent risk factors for higher R-scores (p = 0.041). Patient mortality reached 46%.

CONCLUSION

MDR K. pneumoniae in oncology ICUs shows extensive resistance and multiple genetic associations. Prior healthcare exposure significantly increases resistance burden, emphasizing the urgent need for stringent antimicrobial stewardship and targeted infection control measures.