Dwarfism, Familial, With Muscle Spasms

Clinical Features

Sica et al. (1995) described what they suggested may be a previously unrecognized syndrome. Two brothers, residents of the northern part of Argentina, suffered from intermittent painful muscle contractions in the trunk limbs. These began at the ages of 8 and 10 years and occurred in episodes lasting from some minutes to several hours, repeating many times throughout the day or night and interfering with rest. By the age of 21, the older man had involvement of the temporal, masseter, and neck muscles. The brothers were 1.34 m and 1.30 m tall. Their facial appearance was similar, with large, low-set ears, large beak nose, and slightly prominent eyes. The scalp hair was fragile, thin, and sparse, and hair was absent from the rest of the body. Intellect was normal. The men were observed to have spontaneous, painful, undulating muscle contractions spreading from one muscle to another and changing from one side of the body to the other, lasting 5 to 30 seconds each. Contractions could be elicited by tapping on the muscle. A double first cousin (a son of a sister of the mother by a brother of the father) was said to be affected but was not examined. The father was also said to have been affected but was probably taller. The photographs display strong muscular development.

Inheritance

Sica et al. (1995) thought that pseudodominant inheritance of a recessive or perhaps X-linked recessive type appeared to be possible.