Purple Urinary Bag Syndrome in a Patient with Acidic Urine: A Case Report

Authors

DOI:

https://doi.org/10.5195/ijms.2023.4166

Keywords:

indwelling urinary catheter, pigmentation disorders, Bacteria Urinary Tract Infections, Bacteriuria, Purple urine bag, Purple urine, Case Report, urinary catheters, Urinary tract infection (UTI), Catheter-Related Infection, Urine, Proteus mirabilis

Abstract

Background: Purple urine bag syndrome (PUBS) is a rare condition classically affecting chronically catheterized elderly woman with alkaline urine and constipation. Presentations without these traditional risk factors are exceedingly rare.

The Case: A 76-year-old chronically catheterized Salvadoran man with benign prostatic hyperplasia presented with a 15-month history of recurrent purple urine bag discoloration, dysuria and suprapubic pain. Notably, he lacked fever, flank pain, or constipation. Examination confirmed a purple drainage system and suprapubic tenderness. Urinalysis revealed acidic urine (pH 6). Urine culture identified extended-spectrum β-lactamase (ESBL)-producing Proteus mirabilis susceptible to trimethoprim/sulfamethoxazole but resistant to ciprofloxacin. At the initial encounter, empiric ciprofloxacin was started alongside routine catheter exchange. At a seven-day follow-up, despite the isolate’s resistance, he showed clinical improvement and was transitioned to a targeted regimen. Ultimately, the patient achieved complete resolution after catheter replacement and culture-directed antibiotic therapy, with negative repeat urinalysis and culture at the final follow-up.

Conclusions: This case report expands the recognized clinical spectrum of PUBS by documenting its occurrence in a chronically catheterized male patient with measured acidic urine and no history of constipation. This presentation highlights the importance of clinical awareness to avoid delayed diagnosis of potentially resistant pathogens.   To the best of our knowledge, this represents the first published case of PUBS in El Salvador.

Author Biographies

Paolo Vigne, MD. Universidad Dr. José Matías Delgado, La Libertad, El Salvador.

Paolo Vigne, MD, graduated from the Universidad Dr. José Matías Delgado, La Libertad, El Salvador, in May 2025 from an eight-year medical program. He is a recipient of the Diploma de Honor al Mérito for achieving first place in the poster presentation “Vectores Adenovirales como nueva alternativa en el tratamiento de la enfermedad de Pompe infantil” at the Eleventh Annual Poster Research Competition of the Faculty of Health Sciences “Dr. Luis Edmundo Vásquez.” He has also passed the USMLE Step 1 examination and has authored multiple publications indexed on Google Scholar.

Rodrigo Aparicio, MD. Universidad Dr. José Matías Delgado, La Libertad, El Salvador.

Rodrigo Aparicio, MD, graduated from the Universidad Dr. José Matías Delgado, La Libertad, El Salvador, in May 2025 from an eight-year medical program. He is currently pursuing postgraduate studies in Emergency Medicine in El Salvador and working at the Instituto Salvadoreño del Seguro Social (ISSS). Dr. Aparicio is also an active member of the Salvadoran Red Cross, where he continues to develop his commitment to prehospital and humanitarian medicine. He holds certifications in Advanced Cardiovascular Life Support (ACLS) by the Emergency and Care Safety Institute, and in Prehospital Trauma Life Support (PHTLS) and Advanced Medical Life Support (AMLS) by the National Association of Emergency Medical Technicians (NAEMT). He also completed a Diploma in Clinical Electrocardiography endorsed by the Emergency Medicine Association of El Salvador.

References

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Published

2026-06-25

How to Cite

Vigne, P., & Aparicio, R. (2026). Purple Urinary Bag Syndrome in a Patient with Acidic Urine: A Case Report. International Journal of Medical Students, 103–106. https://doi.org/10.5195/ijms.2023.4166

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