Torsion dystonia, also known as dystonia musculorum deformans, is a disease characterized by painful muscle contractions resulting in uncontrollable distortions. This specific type of dystonia is frequently found in children, with symptoms starting around the ages of 11 or 12. It commonly begins with contractions in one general area such as an arm or a leg that continue to progress throughout the rest of the body. It takes roughly 5 years for the symptoms to completely progress to a debilitating state. Causes
The disease is caused by a genetic disorder which results in a defect in a protein called Torsin A. A mutation in the DYT1 gene causes the loss of an amino acid, glutamic acid, in the Torsin A protein. Torsin A is an evolutionarily conserved AAA+ ATPase. The defective protein creates a disruption in communication in neurons that control muscle movement and muscle control. This mutation is most usually inherited from a parent, but can occur sporadically. The disease is caused by a dominant allele, meaning that the person affected needs only one copy of the mutated DYT1 gene to have symptoms. However, only 30 to 40 percent of those that do have the gene actually have symptoms, leading researchers to believe that there are other factors involved. Diagnosis
Classification
There are several types of torsion dystonia that affect different areas of the body. However, it is unknown if the gene that causes Early Onset Torsion Dystonia is responsible for the other dystonias as well.
Steroids can be used to treat the symptoms of pulmonary or cerebral edema, but do not treat the underlying AMS. Two studies in 2012 showed that ibuprofen 600 milligrams three times daily was effective at decreasing the severity and incidence of AMS; it was not clear if HAPE or HACE was affected. Paracetamol (acetaminophen) has also shown to be as good as ibuprofen for altitude sickness when tested on climbers ascending Everest. See also
References
External links

Travel at High Altitude: a free booklet about how to keep healthy at altitude. Available in many languages. Merck Manual entry on altitude sickness
Altitude Illness Clinical Guide for Physicians