Purple Urine Bag Syndrome in a Woman with Squamous Cell Cervical Cancer

Abstract

Purple urine bag syndrome is a rare phenomenon whose striking presentation can lead to earlier recognition and treatment of a potentially serious medical condition. This is a unique condition of long11 term indwelling catheter associated urinary tract infection with distinct, purple-colored urine caused by bacterial metabolites. This infrequent occurrence was seen in a patient with stage IIIb squamous cervical cancer who presented to the emergency department with symptoms of a urinary tract infection in setting of indwelling bilateral percutaneous nephrostomy tubes. The patient’s physical exam was notable for left costovertebral tenderness, purple urine in bilateral nephrostomy bags and urine culture significant for proteus mirabalis. The patient was treated with intravenous antibiotics and fluid resuscitation. She unfortunately left against medical advice shortly after being admitted. She re presented to an outside hospital with fevers and non-draining nephrostomy tubes notable to have purulent discharge at the nephrostomy sites. The scant urine through the nephrostomy tubes was also noted to have a purple hue. She was found to have another urinary tract infection with Enterobacter cloacae and subsequently treated with intravenous antibiotics. During this admission, she underwent bilateral nephrostograms notable for significant clogging of tubes and bilateral ureteral patency. After the study, she underwent removal of the long-term indwelling catheters and was able to continue voiding spontaneously. She was discharged in good condition on a ten-day course of oral antibiotics. The occurrence of purple urine is highly associated with urinary tract infections. This process is thought to be caused by a metabolism of dietary tryptophan by intestinal bacteria to indole that is then absorbed into the circulation and then converted to indoxyl sulfate by hepatic enzymes. This substrate returns to circulation and is excreted in the urine where in the presence of bacteria with sulfatase and phosphatase activity converts indoxyl sulfate to indigo and indirubin resulting in the characteristic purple hue of the urine. Catheter associated urinary tract infections require antibiotic treatment and timely removal of catheter when appropriate to prevent complications including pyelonephritis and sepsis.