Stroke causes numerous unwanted complications. However, purple urine is not one of them.
Purple Urine Bag Syndrome (PUBS) is an extremely rare phenomenon. It occurs mostly in women, who undergo urinary catheterization for extended intervals. This can occur due to chronic illness or immobility. Catheterization involves the insertion of a tube inside the bladder via the urethra. A bag collects the urine outside of the body.
An elderly French woman presented with the symptoms of a stroke. However, 10 days after urinary catheterization, she was producing purple-tinged urine. This was due to hemiplegia. Hemiplegia is a condition in which one side of the body is paralyzed.
Doctors in the US: To worry or not to worry?
Doctors in the US studied this case. Thankfully, the woman was out of danger. A cross-reaction between the substances in the urine and gut resulted in this color of the urine.
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. However, the urinary pH of this woman was 8. This pH is alkaline.
Certain food substances contain a chemical called Tryptophan. It is metabolized by the liver into indoxyl sulphate. Furthermore, Indoxyl sulphate is broken down into indigo and indirubin in the urine. This occurs in the presence of bacterial enzymes. Indigo and indirubin which are blue and red in color, respectively; give rise to purple color on mixing. The bacteria in charge of this side effect are E. coli, Pseudomonas aeruginosa, and Klebsiella pneumonia.
A happy ending?
Thankfully, there was no need for antibiotics as there were no signs of infection. Furthermore, intravenous fluid administration helped the urine pH and color to return to normal. Unfortunately, she failed to recover from the symptoms of a stroke. Additionally, she lost the ability to speak and was paralyzed on one side of her body. Therefore, 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