27 Rare and Mysterious Medical Conditions

Canities subita is the sudden, seemingly overnight onset of white or gray hair due to stress or some kind of trauma. The most famous such case is that of Queen Marie Antoinette of France, whose hair allegedly whitened shortly before her guillotining in 1793. Some doctors think this autoimmune disorder is connected to melanin, a substance that produces hair and skin pigmentation.

Congenital insensitivity to pain is a condition that makes a person unable to feel any physical pain. People who have CIP are born with it. Since pain is the body’s way of telling people to be careful, those who don’t feel it are at higher risk of serious injuries. For example, they can put their hands into boiling water and not feel anything while their skin is burning. Fewer than 1,000 people in the U.S. are affected by the condition and the odds of a baby being born with it are 1 in 125 million.

Cotard’s Syndrome is a mental disorder in which the person affected by it believes he or she has lost organs, body parts, or is dead. Patients with the condition usually suffer from a mood disorder, a psychotic disorder, or other medical condition. A search of the Mayo Clinic database for the 1996-2016 period revealed 12 cases.

Tree Man Syndrome is a genetic skin disease characterized by a decreased ability to protect against some types of human papillomavirus (HPV), resulting in chronic infections and lesions. The genetic condition, which is rare, may lead to cancer developing in parts of the body that are often exposed to sun.

Exploding Head Syndrome is a sleeping disorder. People affected by it hear loud “exploding” noise (that isn’t real or heard by anyone else) as they transition from wakefulness to deep sleep. The condition, for which the number of cases is not yet known, is not dangerous but people with it often experience fatigue during the day. Though there is no treatment for this type of parasomnia, certain medications may alleviate the symptoms.