Schwartz-Jampel Syndrome with Autosomal-Dominant Inheritance

Abstract

A 4-year follow-up study of 2 brothers affected by Schwartz-Jampel syndrome is reported. The children, aged 16 and 7 years, respectively, showed the clinical and electromyographical signs of the disorder. Further investigation showed some typical facial features of the syndrome, percussion myotonia and abnormal EMG pattern characterized by continuous muscle activity at rest in 3 other members of the same family. On the basis of our data, we suggest that inheritance of the Schwartz-Jampel syndrome may not only be recessive, as reported by most authors, but also dominant, with a different clinical expression.

Schwartz-Jampel Syndrome in Saudi Children

“…In agreement with the data of others, 3,4,7,13,14 the findings of the laboratory evaluation of our cases were normal with the exception of increased concentration of serum CPK and aldolase, which may be explained as a consequence of persistent muscular contraction and hypoxia. In the present report as in others, 3,7,8,15 a continuous, spontaneous, high frequency activity has been observed on EMG studies and these electric discharges increase with movement of the needle, on percussion of the muscle and following voluntary contraction. Although abundant spontaneous EMG activity has been documented in all reported cases of SJS, opinions differ as to its character and origin.…”

“…3,7,11 Patients with this syndrome have been described as being generally normal at birth with the characteristic clinical features only becoming apparent as they grow older. 1,3,4 The clinical symptoms and signs are initially noted in the first two to three years of life, as illustrated in the present cases reported herein, and thereafter the disorder shows a stationary or slowly progressive course.…”

“…The characteristically pinched face is mainly due to the constant state of contraction of facial muscles. 7,11,12 Other frequently occurring features are myopia, ptosis, prominent bushy eyebrows, irregular eyelashes, low-set ears, receding chin, highly arched palate and low position of the hairline on the forehead and neck. 3 These oculofacial abnormalities were demonstrated in our cases, but they were not detected before the age of six months.…”

“…1,6 The inheritance pattern was presumed to be autosomal recessive, though the possibility of an autosomal dominant mode has been suggested in a few cases. 3,7 Case reports of SJS have been described in patients of all major racial groups worldwide. [1][2][3][4][5][6][7][8][9][10] We have had the opportunity to study five Saudi children with almost identical clinical findings of SJS.…”

“…3,7 Case reports of SJS have been described in patients of all major racial groups worldwide. [1][2][3][4][5][6][7][8][9][10] We have had the opportunity to study five Saudi children with almost identical clinical findings of SJS. These cases are presented in order to draw the attention of the practicing clinicians to the existence of this rare syndrome in a country where consanguineous marriage is common.…”