Purple urine bag syndrome is a rare condition in which purple discoloration of urine inside its collection bag occurs. urine bag for the elderly We describe two illustrative cases. A first patient is an 81-year-old man who was hospitalized for a newly diagnosed lymphoma with acute obstructive renal failure for which a nephrostomy procedure was performed. During the hospitalization, a sudden purple discoloration of the suprapubic catheter urine was noted, while the nephrostomy urine had a normal color. Urine culture from the suprapubic catheter was positive for
Pseudomonas aeruginosa and
Enterococcus faecalis; urine from the nephrostomy was sterile. A second case is an 80-year-old man who was admitted for heart failure with a cardiorenal dilemma and who was started on intermittent hemodialysis. There was a sudden purple discoloration of the urine in the collection bag from his indwelling catheter. He was diagnosed with an
E. coli urinary infection and treated with amoxicillin and removal of the indwelling catheter. These two cases illustrate the typical characteristics of purple urine bag syndrome.
1. Introduction
Purple urine bag syndrome is a rare condition characterized by a purple discoloration of urine inside the urine collection bag [
1]. It is mostly seen in patients with chronic urinary catheterization, constipation, and urinary tract infection [
2]. The purple color is thought to be caused by the bacterial metabolization of dietary tryptophan into indigo and indirubin inside the urinary catheter system [
3]. Here, we describe two illustrative cases.
2. Case 1
An 81-year-old man was admitted to the nephrology ward because of anorexia, weight loss, and acute chronic renal failure. His past medical history was remarkable for atrophy of the left kidney, myocardial infarction, follicular type non-Hodgkin lymphoma treated with CHVmP/BV chemotherapy (19 years prior to the present admission), and prostate cancer treated with androgen deprivation (6 years prior to the present admission). The patient had a permanent suprapubic catheter that was changed at 6-weekly intervals. On admission, he was found to have extensive supra- and infradiaphragmatic lymphadenopathy, with encasement of the right ureter and hydronephrosis of the right kidney. An urgent nephrostomy had been performed. Biopsy of a palpable cervical lymph node later revealed diffuse large B-cell lymphoma.
During the hospitalization, a sudden purple discoloration of the suprapubic urine collection bag was noted (see Figure 1). The nephrostomy urine had a normal color. The patient had been constipated during the preceding days, for which he had been treated with macrogol laxatives. His other medications had not been changed and included enoxaparin, aspirin, bisoprolol, amlodipine, rosuvastatin, sertraline, and a three-monthly injection of goserelin. The patient had no other complaints.
