7 Fascinating Diseases Most People Have Never Heard Of.

1. Fibrodysplasia Ossificans Progressiva (FOP)

Our bodies are extraordinarily good at repairing themselves. When we get a bruise, tear a muscle, strain a tendon, our body gets to work repairing the damage. It may take a while, but eventually we're as good as new.

But what if your body replaced your tissue with something truly horrifying?

That's what happens to people with FOP. When their tissue is damaged, their bodies replace it alright - but with bone. For for them, a calf strain could lead to permanent immobility in their leg.

Worse, it sometimes doesn't even require damage to replace tissue with bone. In some patients, it just happens spontaneously. Typically, patients experience the onset of the disease before they turn ten.

The disease usually first takes effect high up on the body - the neck or chest - and then works its way down. Eventually, a person with FOP can find themselves virtually encased in their own bones, unable to move, with difficulty speaking or even eating.

Excessive build-up of bone around the ribcage can restrict the expansion of the lungs, and often leads to FOP patients having difficulty breathing.

FOP has been around for a long time, with cases reported as far back as the 1600s. But the most famous case is that of Harry Eastlack (1933-1973). Eastlack's case was so severe that, before he died, he was almost completely petrified, only able to move his lips.

He graciously donated his body to science, helping researchers as they work to find a cure for this dreadful but rare affliction.

Keep reading on the next page.


Suppose you see a man walking down the street with his arm on fire. He's smiling, whistling, waving at passersby. Is he a stunt man? Is he insane? Or does he suffer from CIPA?

Congenital Insensitivity to Pain with Anhidrosis (CIPA) is an inherited disorder that renders sufferers incapable of feeling much of anything. Heat, cold, pain - any physical sensation perceived by a normal nervous system just doesn't register for them.

As you can imagine, this causes serious problems. While we may not enjoy pain, it's useful for informing us when there's a problem. People with CIPA often suffer severe injuries that are easily avoidable for people who can feel pain, such as burning themselves without noticing.

They also tend to let existing injuries fester because they simply don't notice them. Imagine walking around with a pelvic fracture because you simply didn't know it was there.

Those with CIPA are at a particular risk of overheating. Not only are they unable to feel excessive heat, but their sweat glands also don't function normally due to nerve damage. Sadly, more than half of children with CIPA die from hyperthermia before the age of three.

3. Syndrome X

On 8 January 1993, Melanie Greenberg gave birth to a baby girl, and named her Brooke.

Melanie had been forced to undergo a c-section a month before her due date, so Brooke was on the small side. But apart from a few normal complications, she appeared to be a healthy child. It took her parents quite a while before they realized her body wasn't actually growing. At all.

More about Syndrome X on the next page.

Doctors were unable to explain exactly why. When Brooke's DNA was sequenced, they found no abnormalities in the genes associated with aging.

Brooke also experienced a number of strange medical incidents. On one occasion, doctors diagnosed her as having had a stroke. But when they performed follow-up tests, they found no evidence of any damage whatsoever.

At the age of five, Brooke fell into a deep two-week sleep as a result of what appeared to be a brain tumor. But when she finally awoke, doctors found no trace of the tumor at all. No explanation has ever been provided.

At a loss to explain the cause of Brooke Greenberg's inability to age, her condition was dubbed "Syndrome X".

Brooke passed away in 2013, but additional cases of Syndrome X have emerged. Nobody knows exactly what it is or why it happens, but it is mercifully rare.

4. Guillain-Barr Syndrome

It's a long weekend. You cook up some hamburgers and you maybe don't leave them on the grill as long as you should. So you get a little food poisoning. No big deal. You're sick for a couple days, but you get it out of your system.

After a few days sleeping on the bathroom floor, you're ready to go back to work. But that's when you notice a weird tingling sensation in your toes...

More about Guillain-Barr on the next page.

That's weird, but not immediately worrying. It's easy to shake off the slight sensation and press on with your day.

But when you get home from work that night, you realize that the tingling has begun to work its way up your legs. You're starting to get concerned, but you go to sleep hoping it will be gone when you wake up. And when you wake up, you're in the hospital, unable to move.

That's the experience of Guillain-Barr Syndrome. What begins as a tinging sensation slowly creeps up your body and ends up as full-blown paralysis. Some patients even end up on ventilators because they're unable to breathe on their own.

But here's the good/weird thing: it's only temporary.

With proper treatment, the paralysis subsides, and the patient returns to normal. Guillain-Barr Syndrome wreaks havoc by turning your immune system against you, causing it to attack your nerves. But once your immune system goes back to normal, it's like it never happened.

Nobody really knows the cause of the syndrome. The only clue is that two-thirds of sufferers have had some kind of infection in the weeks prior - often food poisoning.

5. The Capgras Delusion

You meet up with an old friend at a coffee shop to catch up. She looks the same as you remember her, she sounds the same, her perfume smells the same. But deep in your heart you can just tell: something about her isn't right.

More about the Capgras Delusion on the next page.

You start to think she's an imposter. Someone must have replaced your friend with a spy, or an agent, or a robotic replica. Come to think of it, everyone around you seems kind of suspicious.

Could it be that you're living in a real-life version of the Truman Show? Or could it be that you're suffering from the Capgras Delusion - the belief that people you know well are secretly imposters?

Take this doctor's notes on a patient who showed signs of the delusion:

"Mrs. D, a 74-year-old married housewife... received the diagnosis of psychosis because of her belief that her husband had been replaced by another unrelated man. She refused to sleep with him, locked her bedroom and door at night, asked her son for a gun, and finally fought with the police when attempts were made to hospitalise her."

Most people who suffer from the Capgras Delusion are paranoid or schizophrenic, although it has also been linked to diabetes, hypothyroidism, brain damage, and migraines.

Providing therapy to Capgras patients can be difficult because they will reject the therapist if they directly confront the delusion, while playing into it isn't helpful either.

6. Dancing Plague

Nobody knows what caused Dancing Plague. Some theorize it was a side effect of poisoning; some that it was a result of brain inflammation; some say it was just a form of mass hysteria brought about by cults. Whatever the cause, it swept through Europe between the thirteenth and sixteenth centuries.

Read more about Dancing Plague on the next page.

One of the first "outbreaks" was in the city of Aachen in 1374. Thousands of people - men, women, and children - spontaneously began to dance, and didn't stop until they collapsed from exhaustion. Some even broke their ribs and died.

Throughout the next two centuries, similar events would occur throughout the continent, seemingly unrelated and not prompted by anything in particular. Dancers would flail about madly for days or weeks or even months.

A number of cures were tried, including exorcism, with mixed results. To this day, nobody has the faintest idea what this phenomenon was or why it happened. The best going theory is that Dancing Plague was a mass psychogenic illness - with similar physical symptoms in many individuals, but no actual medical cause.

7. Myotonic Hypertrophy

We should end on a positive note. Here's a rare genetic condition that is actually sounds pretty cool.

People with MH tend to have, by virtue of their condition, remarkably little body fat. As a trade-off, they have about twice the muscle mass as a normal person. On top of that, their muscle strength is off-the-charts, so even if they had only average muscle mass, they would still be unusually strong.

"But wait," you ask, "What horrible consequences accompany this otherwise perfectly beneficial disease? Surely they must pay a terrible price for all that muscle tone."

Nope. There are no known side effects, either physical or mental. You know, I think I feel a touch of Myotonic Hypertrophy coming on right now.

...Well, a guy can dream.








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