1. Fibrodysplasia ossificans progressiva - Fibrodysplasia ossificans progressiva (FOP) is an extremely rare disease of the connective tissue. Essentially, this disease screws up the body's repair mechanism, causing fibrous tissue (including muscle, tendon, and ligament) to be ossified when damaged. Ossified - turn to bone! In many cases, injuries can cause joints to become permanently frozen in place. What's worse, surgical removal of the extra bone growths has been shown to cause the body to "repair" the affected area with more bone.
This is a terrifying disease because it restricts your life so much. You can't put yourself at risk of injury, otherwise you risk ossifying a part of your body, and losing movability of that body part. That effectively rules out almost all physical activity! Being careful/paranoid doesn't guarantee that you won't suffer some sort of injury, and the moment you do, you will probably be permanently disfigured.
The best known FOP case is that of Harry Eastlack (1933–1973). His condition began to develop at the age of ten and, by the time of his death from pneumonia in November 1973, six days before his 40th birthday, his body had completely ossified, leaving him able to move only his lips.
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| Image thanks to this source. Notice that the bone has "grown" irregularly, leaving a man stiff in areas where he should be able to move. |
Why is it terrifying? Imagine that you're taking a simple, relaxing swim in a pond or lake. Then unknowingly, N. fowleri can enter your body normally via the nose. You can not detect it or shoo it away. And here's where it gets scarier.
The more common name of this organism is "brain-eating amoeba," and it's meant in a literal sense. While it rarely attacks, it almost always means death. How does a very small organism like N. fowleria do that much damage to a human?
In humans, N. fowleri can invade the central nervous system via the nose. The penetration initially results in significant necrosis of and hemorrhaging in the nose. From there, they climb along nerve fibers into the brain. The amoebae begin to consume the cells of the brain piecemeal by means of a unique sucker apparatus extended from their cell surface. It then becomes pathogenic, causing primary amoebic meningoencephalitis (PAM or PAME). PAM is a syndrome affecting the central nervous system, characterized by changes in olfactory perception (taste and smell), followed by vomiting, nausea, fever, headache, and the rapid onset of coma and death in two weeks.
3. Fatal familial insomnia - This is by far the most terrifying disease I've ever come across. As you can probably determine from the name of the disease, it is fatal insomnia. So, one night, you realize that you can no longer sleep even though you're very tired. Then the next. And the next. And the next. Until you die.
Here's one story of a person who suffered from such disease:
Shortly after his 40th birthday in 1991, Michael Corke, a music teacher from Chicago, began having trouble sleeping. In the following weeks, the insomnia grew worse and his health rapidly deteriorated. Eventually he couldn’t sleep at all.
The doctors were baffled but could do nothing for him. Michael was physically and mentally exhausted, and wanted nothing more than to be able to fall asleep. But his brain wouldn’t let him.
Video footage of him appearing at a school orchestra concert revealed a frail old man - a far cry from the fit and healthy individual he was just months earlier. Eventually he was admitted to hospital and doctors diagnosed him with an extremely rare genetic disorder discovered just seven years prior: Fatal Familial Insomnia (FFI).
Michael Corke died in hospital after six months from a complete lack of sleep.
Fatal Familial Insomnia strikes between the ages of 30 and 60 years, with no apparent trigger that the sufferer can relate to. Patients have been known to survive for up to three years, gradually passing through four stages of illness:
1. The onset of insomnia, creating panic attacks and unfounded phobias, lasting for four months.
2. Severe insomnia, worsening panic attacks and hallucinations, lasting for five months.
3. Complete insomnia and rapid weight loss, lasting for three months.
4. Dementia and unresponsiveness, lasting for six months. FFI is eventually fatal.
Why is this so terrifying? Have you ever gone for a week without sleep? Just imagine how much this pain/exhaustion/depression will be magnified, if this is to last for as long as you live (not long, actually).
Thanks to wikipedia and suite101.com for the references.
