Purple Urine Bag Syndrome: A Rare Phenomenon Managed in Primary Care

Abstract

Purple urine bag syndrome (PUBS) is a rare manifestation of urinary tract infection (UTI) characterized by bluish-purple discoloration of urine, typically seen in patients with long-term urinary catheters. It occurs due to the bacterial metabolism of dietary tryptophan into indole, which is converted into indoxyl sulfate in the liver and then excreted in the urine, where it reacts with catheter materials under alkaline conditions. Risk factors include chronic constipation, advanced age, female gender, dehydration, and recurrent UTIs. Morganella morganii is one of the bacteria commonly implicated. Although usually benign, PUBS can signal underlying UTIs, especially in asymptomatic patients.The case presented involves an 81-year-old woman with a history of urothelial carcinoma and a monoJ catheter since pelvic exenteration and ureterostomy. She presented with blue-colored urine in the collection bag; she was asymptomatic, but the urinalysis had leukocytes, nitrites and alkaline pH, and the uroculture was positive for M. morganii. Antibiotic therapy resolved the symptoms initially, but recurrence prompted further treatment and optimization of constipation management. PUBS, although rare, poses risks, especially in vulnerable populations. Identification of risk factors and causative agents is crucial for effective treatment, typically involving catheter replacement, antimicrobial therapy, and constipation correction. Prevention focuses on minimizing catheter use, regular replacement, and hygiene optimization. Early recognition and management in primary care settings can prevent complications and reduce patient and caregiver distress.In conclusion, PUBS is a visually evident condition that may serve as an early indication of UTI, particularly in patients with chronic catheterization. Treatment and prevention strategies should be tailored to individual risk factors to prevent the recurrence or persistence of the syndrome. Awareness among healthcare professionals and patients is essential for timely diagnosis and management. The presented case demonstrates the importance of primary care in managing complex conditions and highlights the close patient-physician relationship in such settings.