Meet the Woman Who Sweats Blood When She Feels Stressed or Exercises

One Italian woman baffled doctors in Florence with an extremely rare condition that causes her to sweat blood from her face and the palms of her hands.

The unnamed 21-year-old patient had no wounds or lesions on her skin, nor did she have any obvious triggers for the spontaneous bleeding, the Daily Mail reports.

The bleeding could happen while she exercised or slept, but it was at its most intense when she was stressed, according to the Canadian Medical Association Journal.

Doctors in Florence report that the patient had suffered the unusual symptoms for the past three years and episodes last between one and five minutes.

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When blood tests came back normal, doctors eventually diagnosed her with hematohidrosis, which is thought to affect just one in 10 million people.

The condition is so rare that doctors aren't even sure how legitimate it is, the Daily Mail reports.

Canadian medical historian and hematologist Jacalyn Duffin, who wrote a commentary that accompanies the journal article, admitted she was at first skeptical of the case and suspected that the Italian doctors had been duped. But after reading the medical literature, she changed her reasoning.

While not much is known about hematohidrosis, one study from the Indian Journal of Dermatology reports that blood vessels surrounding the sweat gland actually constrict, or narrow, under the pressure of stress. So as anxiety increases, the blood vessels dilate to the point of rupture. The blood enters the sweat glands and is pushed to the surface of the skin along with sweat.

The 21-year-old woman diagnosed with the rare condition was given beta blockers, which have substantially reduced her symptoms but has not completely stopped them. She has reportedly become depressed and socially isolated because of her condition.