There are numerous unwanted complications that can occur due to stroke. Purple urine, however, is not one of them.
Purple Urine Bag Syndrome (PUBS) is an extremely rare phenomenon occurring mostly in women, who undergo urinary catheterization for extended intervals, because of chronic illness and immobility. Catheterization involves the insertion of a tube inside the bladder via the urethra, that is connected to a bag outside for urine collection.
A 70-year-old French woman who was initially hospitalized for stroke, but 10 days after urinary catheterization, owing to paralysis of one side of the body, known as hemiplegia; was found to have purple-tinged urine.
Doctors in the US: To worry or not to worry?
The case was studied by doctors in the US, and fortunately, there was no danger involved. The discolored urine was simply a cross-reaction of substances found in the urine and gut.
Dr. Guy Mintz, Northwell Health’s Sandra Atlas Bass Heart Hospital in Manhasset, N.Y.
"In the spirit of Halloween, even paranormal activity like purple urine can be explained scientifically."
Purple Urine: A “colorful” story
Normally, urine excreted from the body is acidic. In this case, however, the pH of the urine was found to be 8, which is alkaline.
Tryptophan, a chemical found in certain food substances, is metabolized by the liver into indoxyl sulphate. Indoxyl sulphate under the presence of bacterial enzymes in the urine is broken down into indigo and indirubin. Indigo and indirubin, blue and red in color, respectively; on mixing give rise to the purple hue. The bacteria in charge of this adverse reaction are E. coli, Pseudomonas aeruginosa, and Klebsiella pneumonia.
A happy ending?
Thankfully, due to the absence of signs of infection in the patient, there was no need for antibiotic intervention. The urine pH and color returned to normal in about 4 days following intravenous fluid administration. Unfortunately, she failed to recover from the symptoms of stroke and was deemed permanently disabled due to loss of ability to speak and paralysis of one side of the body. She was referred to a long-term care facility for proper care.
Plaçais, L., & Denier, C. (2019). Purple Urine after Catheterization. New England Journal of Medicine, 381(18), e33. doi:10.1056/nejmicm1905446