The doctors from the University of Florence published details on the perplexing case this week, revealing more layers to the mystery.
In a commentary published with the initial case report, medical historian Jacalyn Duffin of Queen's University in Canada suggests that incidents of spontaneous blood sweat actually span the globe and go back thousands of years.
There's even a name for the condition – hematohidrosis – but it's so exceedingly rare that researchers have essentially ignored the phenomenon. No one had previously connected the dots in the medical literature.
Duffin found more than two-dozen cases of the condition from around the world in the past 15 years. In these modern cases, doctors had used modern methods of diagnosis to confirm that the blood was indeed seeping through the skin.
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Duffin discovered reports of spontaneous bleeding going all the way back to the writings of Aristotle. She rooted out more than 40 references from the Middle Ages through to the 19th century. While some of these writings are simple descriptions, others are the equivalent of case reports from physicians of each era.
“When I saw the Italian case, I was really skeptical, quite honestly,” Duffin told Seeker. “There are so many similarities in the clinical presentation that I basically talked myself out of skepticism and I now believe that it's possible and plausiable that it happens.”
Duffin, initially recruited to peer-review the Italian report, said she quickly became fascinated by the topic.
“I got a double whammy on that one, because I'm both a hematologist and a medical historian,” she said.
Duffin believes incidents of hematohidrosis may be underreported. Doctors are hesitant to document or publish when they comes across a condition that isn't in the medical literature. The assumption is often that the patient is faking it, or is somehow deluded.
“That raises the question, are doctors ignoring it?” Duffin said.
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There's also the issue of religious significance. In Christianity, spontaneous bleeding through the skin is associated with the stigmata — the crucifixion wounds of Christ. Throughout history, individuals have claimed to experience stigmata, and many of these cases have subsequently been proven fraudulent.
But, according to Duffin’s research, hematohidrosis is a very real condition.
“It's perhaps easier for me than other doctors to find the cases in the 16th and 17th century literature,” she said. “It's rare, but observations have been going back to the third century BC. And the most recent cases are from all over the world.”
And, Duffin added, the Italian case has brought about another twist.
“Since [the case] got published on Monday, I've heard from four people who claim they have it,” she said. “And that their doctors treat them very badly.”
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