Essentially any disorder that causes some form of neuronal loss or gliosis in the basal ganglia has the potential to cause hemiballismus. Nonketotic hyperglycemia
Patients with nonketotic hyperglycemia can develop hemiballismus as a complication to the disease through the development of a subthalamic nucleus lesion. This is the second most common reported cause of hemiballismus. It can be found primarily in the elderly and many of the reported cases have come from East Asian origin, which suggests that there may be some genetic disposition to development of hemiballismus as a result of hyperglycemia. Hemiballistic movements appear when blood glucose levels get too high and then subside once glucose levels return to normal. This time scale for this is usually several hours. In patients with this type of hemiballismus, imaging reveals abnormalities in the putamen contralateral to the movements as well as the globus pallidus and caudate nucleus. While the hyperglycemia itself is not the cause of the hemiballistic movements, it has been suggested that petechial hemorrhage or a decreased production of GABA and acetylcholine could result secondary to the hyperglycemia. One of these issues could be responsible for the hemiballistic movements. Neoplasms
A neoplasm is an abnormal growth of cells. Cases have shown that if this occurs somewhere in the basal ganglia, hemiballismus can result. Vascular malformations
Vascular malformations can cause abnormal blood flow to areas of the brain. If too little blood is delivered to the basal ganglia, a stroke can occur.
Other diagnostic tests are useful in excluding other similar conditions, but history, X-ray, and biopsy are essential. These other tests may include basic blood work, blood cultures, and bronchoalveolar lavage. The clinical picture is similar to ARDS, but AIP differs from ARDS in that the cause for AIP is not known. Treatment
Treatment is primarily supportive. Management in an intensive care unit is required and the need for mechanical ventilation is common. Therapy with corticosteroids is generally attempted, though their usefulness has not been established. The only treatment that has met with success to date is a lung transplant. Prognosis
Sixty percent of people with acute interstitial pneumonitis will die in the first six months of illness. The median survival is 1+1⁄2 months. However, most people who have one episode do not have a second. People who survive often recover lung function completely. Epidemiology
Acute interstitial pneumonitis occurs most frequently among people older than forty years old. It affects men and women equally. There are no known risk factors; in particular, smoking is not associated with increased risk. History
Acute interstitial pneumonitis was first described in 1935 by Louis Hamman and Arnold Rich, and given the name Hamman–Rich syndrome. References
External links

synd/3010 at Who Named It? 00181 at CHORUS