[Urinary infection and pyelonephritis]

Area of Science:

• Urology
• Infectious Diseases
• Clinical Microbiology

Context:

• Urinary tract infections (UTIs) and pyelonephritis are common clinical disorders with evolving diagnostic and management concepts.
• Accurate etiological diagnosis is crucial for effective treatment and prognosis.

Purpose:

• To evaluate the reliability of different urine sample collection techniques for diagnosing UTIs.
• To identify predisposing factors associated with UTIs and their impact on clinical outcomes.

Summary:

• Bacteriological analysis of 245 urine samples assessed suprapubic puncture, single midstream voiding culture, and serial midstream cultures.
• Escherichia coli was the predominant pathogen (91% of initial episodes, 87% of recurrences).
• Suprapubic puncture demonstrated the highest reliability, avoiding sample contamination. Serial midstream cultures showed good correlation with suprapubic puncture, while single midstream cultures yielded a 50% false-positive rate. Predisposing factors, particularly intra-urinary tract issues like vesicoureteral reflux (52% in affected patients), were present in 68% of UTI cases.

Impact:

• Highlights the importance of reliable urine culture techniques for accurate UTI diagnosis.
• Emphasizes the critical role of identifying predisposing factors in managing UTIs, influencing infection site, recurrence, chronicity, treatment, and prognosis.
• Recommends suprapubic aspiration or serial midstream cultures for improved diagnostic accuracy in UTI cases.