What causes black urine?
November 3, 2010, 11:49 pm
A case of black urine and dark skin – cresol poisoning. Seak CK et al. Clin Toxicol 2010 Oct 6 [Epub ahead of print]
Cresol — derived from phenol — is a common disinfectant. Acute cresol toxicity presents with corrosive gastrointestinal injury and multi-organ failure. Another characteristic finding in cresol poisoning is black urine. This case report — describing a 42-year-old man who ingested cresol in a suicide attempt — is illustrated with a photograph of the strikingly dark urine.
As the authors note, other causes of black urine include hemoglobinuria, myoglobinuria, alcaptonuria, melanuria, porphyrinuria, tyrosinuria, and malignant melanoma.
Addendum (11/10/10): Chris Nickson from Life in the Fast Lane wrote to point out that last year Annals of Emergency Medicine published a very similar case of cresol poisoning, with a great picture of the urine. To read the brief report and see the picture, click here.