If you're squeamish, you might want to stop reading now.
A case study from the Canadian Medical Association Journal reports that doctors in Italy were baffled by a woman whose rare condition caused her to sweat blood — literally.
The report, published on Monday, said that doctors treated a 21-year-old unidentified woman who checked into a medical ward with a strange symptom: She had been bleeding from her face and palms periodically over the course of three years, with no apparent cause.
"There was no obvious trigger for the bleeding, which could occur while she was asleep and during times of physical activity," researchers said in the study. "She stated that more intense bleeding occurred during times of perceived emotional stress. Episodes lasted from one to five minutes."
Doctors reported that the woman had no visible broken skin, and the woman became socially isolated because of the condition. They treated her for symptoms of major depressive disorder as a result of that isolation, but otherwise, her physical tests came back without any abnormalities.
Eventually, they were able to diagnose her with a very rare condition, known as hematohidrosis. According to the Genetics and Rare Diseases Information Center, symptoms include blood coming from intact skin, as well as crying bloody tears, or even bleeding from the ears.
Doctors were able to treat the woman with propranolol, a beta-blocker that can be used to regulate blood pressure and heart rate. The bleeding didn't go away completely, but the treatment resulted in a "marked reduction" of her symptoms.
While the bleeding is caused by ruptured small blood vessels on the skin, researchers noted that "there is no single explanation of the source of bleeding in hematohidrosis."