Battling urinary tract infections: Unravelling the etiological spectrum and resistance repertoire of causative non-fermenting Gram-negative bacilli

Objective: To ascertain the microbial landscape of uropathogenic non-fermenting Gram-negative bacilli (NFGNB) and their antimicrobial susceptibility profile in an Indian tertiary care hospital setting. Methods: A retrospective observational study was conducted from May to October 2024, at a tertiary care hospital in India. Urine specimens were processed and bacterial identification was performed as per standard protocol. Antimicrobial susceptibility testing was performed in accordance with Clinical and Laboratory Standard Institute guidelines. The etiological and antimicrobial susceptibility profiles of the uropathogenic NFGNB isolates were retrieved from laboratory records and analyzed. Results: Among the 24 286 urine specimens received during the study period, 12.3% (2 992/24 286) showed significant bacteriuria, of which 5.7% (171/2 992) were identified as NFGNB. The predominant NFGNB was Acinetobacter spp. (48.5%) followed by Pseudomonas spp. (48.0%, 82/171), with Acinetobacter baumannii being the most common NFGNB (42.1%, 72/171) isolated. Acinetobacter baumannii exhibited significantly lower susceptibility to carbapenems (38.9%-44.4%) compared to Pseudomonas aeruginosa (69.6%—75.4%) ( P =0.001). Among the NFGNB, 56.5% were multidrug-resistant, 34.1% extensively drug-resistant and 15.9% pandrug-resistant. Multidrug-resistant and extensively drug- resistant rates were significantly higher in Acinetobacter species than in Pseudomonas species ( P =0.001 and P =0.002, respectively) with inpatient isolates showing significantly lower antimicrobial susceptibility patterns. Conclusions: The high prevalence of multidrug-resistant strains of uropathogenic NFGNB, especially in hospitalized patients, underscores the need for strengthened infection prevention and control practices and continuous ongoing surveillance activities to gain a more comprehensive understanding and improve clinical outcomes.