Diagnostic dilemma: A woman started sweating blood from her face and hands

The patient: A 21-year-old woman in Italy

The symptoms: Over the course of three years, the woman would occasionally bleed from her face and palms, despite not having any cuts or scratches. There was no obvious trigger for the bleeding, which would last from one to five minutes. It wasn't linked to a particular physical activity; it could happen when she was exercising or sleeping, for example. However, the patient noticed that the bleeding episodes seemed more severe when she was emotionally stressed.

What happened next: Upon being admitted to the hospital, the patient had been feeling depressed and experiencing panic attacks, and she had become socially isolated because she was embarrassed by the bleeding episodes. While examining her, doctors noticed what they described as "the discharge of blood-stained fluid from her face," according to a case report published in the Canadian Medical Association Journal.

Doctors examined the bloody secretion under a microscope and confirmed the presence of red blood cells.

The diagnosis: The blood cells ruled out the possibility of a factitious disorder, or the notion that the woman was pretending to be sick. It also ruled out various disorders that cause "colored sweat," like chromhidrosis. Therefore, the doctors diagnosed the woman with hematohidrosis, a rare disease in which "blood sweat" spontaneously discharges through a person's uninjured skin. The patient's blood tests showed normal results, as did microscopic analyses of the patient's skin.

The treatment: Doctors prescribed the young woman a daily dose of propranolol, a beta-blocker that's usually used for heart- and circulation-related issues. In their report, the doctors said they opted for this drug because it had previously been used in similar cases. Although the drug noticeably decreased the amount of bleeding, it did not completely stop it.

What makes the case unique: As in other reported cases of hematohidrosis, the doctors could not explain exactly how or why the woman was bleeding through her undamaged skin.

In their report describing this case, they noted various theories that attempt to explain the condition. For example, some think systemic diseases that affect blood clotting may be to blame. Others suggest overactivation of the fight-or-flight system may play a role.

It's also not known how the blood physically passes through the skin. There's no evidence to suggest the blood makes its way through the sweat glands; some reports describe bleeding through the hair follicles. Furthermore, some patients have also experienced such bleeding in areas that don't have sweat glands, like the tongue or under their nails.

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