Clinical Profile, Microbiological Spectrum, And Antibiotic Resistance Patterns of Complicated Urinary Tract Infections at A Tertiary Care Hospital.

Original Article

Abstract

Background: Complicated urinary tract infections (cUTIs) are associated with significant morbidity, prolonged hospitalization, and increased healthcare costs, particularly among patients with underlying urological abnormalities and comorbidities. The growing prevalence of antimicrobial-resistant uropathogens has reduced the effectiveness of empirical antibiotic therapy, emphasizing the importance of understanding local microbiological patterns and resistance profiles to guide appropriate treatment and antimicrobial stewardship.

Objective: To determine the clinical profile, microbiological spectrum, antimicrobial resistance patterns, and associated factors of multidrug-resistant organisms among hospitalized adult patients with complicated urinary tract infections.

Methods: This cross-sectional observational study was conducted in the Department of Nephrology Prime Teaching Hospital Peshawar, Pakistan, from January to June 2025.A total of 100 adult patients with clinically diagnosed complicated urinary tract infections were enrolled through consecutive non-probability sampling. Clinical characteristics, associated risk factors, urine culture findings, isolated microorganisms, and antimicrobial susceptibility patterns were recorded using a structured proforma. Antibiotic susceptibility testing was performed according to Clinical and Laboratory Standards Institute (CLSI) recommendations. Data were analyzed using SPSS version 27.0. Continuous variables were expressed as mean ± standard deviation, categorical variables as frequencies and percentages, and p-values <0.05 were considered statistically significant.

Results: The mean age of participants was 54.8 ± 15.2 years, and 58% were male. Diabetes mellitus (46%), urinary tract obstruction (31%), indwelling urinary catheterization (28%), and nephrolithiasis (24%) were the predominant risk factors. Fever (78%), dysuria (69%), flank pain (57%), and urinary frequency (52%) were the most common presenting symptoms. Urine cultures were positive in 91% of patients. Escherichia coli was the predominant pathogen, accounting for 51 (56.0%) of the 91 culture-positive isolates, followed by Klebsiella pneumoniae (19.8%), Pseudomonas aeruginosa (11.0%), and Enterococcus faecalis (6.6%). High resistance was observed to ampicillin (82%), ciprofloxacin (68%), and ceftriaxone (61%), whereas meropenem (9%), amikacin (18%), and nitrofurantoin (22%) showed comparatively lower resistance. Multidrug-resistant organisms were identified in 39 of 91 culture-positive isolates (42.9%) and were significantly associated with diabetes mellitus (p=0.018), indwelling urinary catheterization (p=0.031), and urinary tract obstruction (p<0.001).

Conclusion: Escherichia coli was the predominant pathogen causing complicated urinary tract infections, with a high prevalence of antimicrobial resistance to commonly prescribed empirical antibiotics. Routine urine culture, antimicrobial susceptibility testing, and continuous surveillance of local resistance patterns are essential for optimizing empirical therapy, strengthening antimicrobial stewardship, and improving patient outcomes.