Sweating blood? It happens — and not just on Halloween


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Halloween got a little weirder this year with news that some people can actually sweat blood. At first there was only one case, discovered by doctors in Florence, Italy, published in the CMAJ on Monday. But since then more cases of sweating blood have been reported to Jacalyn Duffin, a Canadian historian and hematologist, who searched the medical literature for references to this bizarre condition.

‘It seems that humans do sweat blood, albeit far less often literally than metaphorically.’ Jacalyn Duffin, medical historian, Queen’s University

When the Italian physicians first encountered the 21-year-old woman who appeared to sweat blood, they assumed she was faking the condition. But then they diagnosed her with hematohidrosis, a rare disease characterized by the “spontaneous discharge of ‘blood sweat’ through intact skin,” although they still don’t know what causes it or how the blood ends up passing through the skin like sweat.

The alarming image of the unidentified woman’s blood-dripping face triggered a media frenzy, causing the CMAJ to temporarily drop its paywall.

Duffin is intrigued by that reaction. She searched back through the medical literature and found reports about sweating blood that dated back to the third century BC.

“It seems that humans do sweat blood, albeit far less often literally than metaphorically,” she wrote in a commentary accompanying the medical report.

Even though the literature indicates it’s been happening throughout human history, Duffin notes that there is a reluctance to believe in sweating blood, possibly because of its association with “religious mystery.”

Hematohidrosis patient

Jacalyn Duffin, a Canadian historian and hematologist, says five people have reached out to her in recent days to say they’ve experienced sweating blood. (CMAJ)

“Other rare conditions are not viewed with similar skepticism,” she wrote. “Ironically, for an increasingly secular world, the long-standing association of hematohidrosis with religious mystery may make its existence harder to accept.”

Since Monday, Duffin has been contacted by five people who say they’ve experienced the strange occurrence of sweating blood.  Now she’s working with a blood coagulation expert and a dermatologist to further investigate this perplexing condition.

Why thinking about nothing is a good thing

Ever been told to stop daydreaming? A new study suggests mind wandering — or in neuroscience-speak, having “task-unrelated thoughts” — might be a sign of a superior brain.

“It might not be as inherently negative as we have been thinking of it to be and there might actually be some positive attributes associated with mind wandering,” said Christine Godwin at the Georgia Institute of Technology, lead author of the paper published recently in the journal Neuropsychologia.

‘Their brains function more efficiently and they have extra capacity to maintain performance on easy tasks.’  – Christine Godwin, Georgia Institute of Technology 

Godwin examined the brain activity of more than 100 people who remained awake but thinking of nothing in particular. The measurements were conducted using a functional magnetic resonance imaging (fMRI) scanner — a machine that measures brain activity by detecting changes in blood flow. When Godwin compared the brain scans to other tests, she concluded that daydreamers were more creative and intelligent.

Godwin’s theory is that someone who is daydreaming in the middle of a task or a meeting is actually demonstrating that they have the mental flexibility to listen with “half an ear” and still know what’s going on in the room.

“Their brains function more efficiently and they have extra capacity to maintain performance on easy tasks and also letting themselves think about other things that interest them as well,” Godwin said.


Scientists believe daydreaming could be a sign of intelligence and creativity. (Shutterstock)

Godwin’s study is part of an effort by scientists to find out what’s really going on in the brain when a person appears to be doing nothing but staring into space.

Increasingly research is focusing on an intriguing neural network called the “default mode,” discovered in the early 2000s after scientists noticed unexplained brain activity during fMRI scans even though subjects were just daydreaming.

It’s been shown that the default mode network is altered by a range of different neurological disorders including Alzheimer’s and autism, but so far no one has been able to explain why it is affected or what exactly it does.

One group at the University of Cambridge published some results this week suggesting the default mode network is involved when we switch to autopilot while we’re doing familiar tasks.

‘The inference is that, indeed, you may well be stuck in your memories and over-thinking and over-analyzing.’  -Dr. Emmanuel Stamatakis, University of Cambridge

“It’s an area in the middle of the brain that is very well connected to all other parts of the brain so it has access to your memory so it can do a lot of different and useful things, one of which is this autopilot role,” said Dr. Emmanuel Stamatakis at the University Of Cambridge.

The researchers believe the default network helps the brain make fast decisions during familiar tasks. It might explain that sensation of not being completely aware of what you’re doing while driving a familiar route, for example.

The network has also been linked to depression and scientists hypothesize that some people have trouble moving out of the default mode.

“The inference is that indeed you may well be stuck in your memories and overthinking and overanalyzing and you don’t take as much cueing from the external world,” said Stamatakis.

Robotic-assisted surgery costs more — and takes longer

First came laparoscopic surgery — techniques allowing surgeons to use multiple small incisions rather than making a big cut — and then came the robots, where laparoscopic instruments are robotically operated and remotely controlled by the surgeon.

The robotic-assisted techniques have been widely adopted, but how are they doing? Research published this week in JAMA gave robotic operations mixed reviews. The authors evaluated more than 23,000 patients who underwent kidney removal surgeries — known as nephrectomies —  in 416 U.S. hospitals between 2003 and 2015.

Robotic surgery

A JAMA study suggests robot-assisted surgery adds costs and takes longer. (Shutterstock)

About 20 per cent of the subjects had robotic-assisted procedures, while the rest had regular laparoscopic surgeries conducted only by the surgeons themselves.

The good news is that there were no significant complications associated with the increasingly common robotic procedures.

The not-so-great news is that the robot-assisted kidney operations took longer, and as a result, cost more in operating-room time and supplies.

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