Community and healthcare-associated UTIs: antimicrobial resistance patterns in a Tunisian emergency-intensive care unit

INTRODUCTION: Urinary tract infections (UTIs) are a leading cause of antibiotic use globally, with rising antimicrobial resistance (AMR) complicating management-particularly in healthcare settings. METHODOLOGY: This cross-sectional study compared community-acquired (CA-UTI) and healthcare-associated UTIs (HA-UTI) at the Habib Thameur Hospital's emergency-intensive care unit in Tunis during 2022-2023. RESULTS: Out of a total of 4,474 urine samples, 446 (10%) were culture-positive. The patients were predominantly elderly (73.3% were ≥ 60 years). More females had CA-UTI (M:F = 0.57) than HA-UTI (M:F = 0.78). Escherichia coli was the main pathogen causing both CA-UTI (57.4%) and HA-UTI (44.6%), while Klebsiella pneumoniae was the more common pathogen in HA-UTI (26.1% vs. 23.3%). Gram-negative bacteria accounted for 90.6% of isolates. Among the K. pneumoniae isolates, resistance to imipenem was significantly higher among HA-UTI isolates (29.2% vs. 5.9%; p = 0.02). Among the E. coli isolates, resistance to nitrofurantoin was significantly higher among HA-UTI isolates (3.7% vs. 12.5%; p = 0.01). Extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae were detected in 8.5% of isolates (mostly E. coli and K. pneumoniae), and carbapenem-resistant Enterobacteriaceae (CRE) in 8.7% (predominantly K. pneumoniae in HA-UTI). CRE showed near-complete β-lactam resistance and high non-β-lactam resistance in HA-UTI. CONCLUSIONS: Rising UTI rates and alarming AMR trends, particularly in HA-UTIs, highlight the need for enhanced antibiotic stewardship and tailored empirical therapy. The predominance of multidrug-resistant strains underscores the urgency for infection control measures in Tunisian healthcare settings.