Tetanus, also known as lockjaw, is a bacterial infection caused by Clostridium tetani, and is characterized by muscle spasms. In the most common type, the spasms begin in the jaw and then progress to the rest of the body. Each spasm usually lasts a few minutes. Spasms occur frequently for three to four weeks. Some spasms may be severe enough to fracture bones. Other symptoms of tetanus may include fever, sweating, headache, trouble swallowing, high blood pressure, and a fast heart rate. Onset of symptoms is typically three to twenty-one days following infection. Recovery may take months. About ten percent of cases prove to be fatal.C. tetani is commonly found in soil, saliva, dust, and manure. The bacteria generally enter through a break in the skin such as a cut or puncture wound by a contaminated object. They produce toxins that interfere with normal muscle contractions. Diagnosis is based on the presenting signs and symptoms. The disease does not spread between people.Tetanus can be prevented by immunization with the tetanus vaccine. In those who have a significant wound and have had fewer than three doses of the vaccine, both vaccination and tetanus immune globulin are recommended. The wound should be cleaned and any dead tissue should be removed. In those who are infected, tetanus immune globulin or, if unavailable, intravenous immunoglobulin (IVIG) is used. Muscle relaxants may be used to control spasms.
Cause
Recent research suggests that AHC is caused by a de novo (spontaneous) genetic mutation in the ATP1A3 gene on chromosome 19 (locus 19q13.31) which encodes enzyme ATP1A3. A small number of cases seem to be caused by a mutation in the ATP1A2 gene. Where the mutation is inherited, it has the autosomal dominant pattern of inheritance.Previously AHC was thought to be a form of complicated migraine because of strong family histories of migraine reported in AHC cases. AHC has also been considered to be a movement disorder or a form of epilepsy. Suggested causes have included channelopathy, mitochondrial dysfunction, and cerebrovascular dysfunction. The disorder most closely related to AHC is familial hemiplegic migraine which is caused by a mutation in a gene for calcium channel receptors. It was thus thought that AHC may be caused by a similar channelopathy. Diagnosis
As of 1993 only approximately 30 people with AHC had been described in scientific literature. Due to the rarity and complexity of AHC, it is not unusual for the initial diagnosis to be incorrect, or for diagnosis to be delayed for several months after the initial symptoms become apparent. The average age of diagnosis is just over 36 months. Diagnosis of AHC is not only difficult because of its rarity, but because there is no diagnostic test, making this a diagnosis of exclusion. There are several generally accepted criteria which define this disorder, however other conditions with a similar presentation, such as HSV encephalitis, must first be ruled out.