Chondrodystrophic myotonia (schwartz‐jampel syndrome): Report of a new case and follow‐up of patients initially reported in 1969

Abstract

We report on a 9-year-old boy with chondrodystrophic myotonia (Schwartz-Jampel syndrome) and the progress of a brother and sister with this syndrome first described in 1969. This is an autosomal recessive trait characterized by mask-like face, narrow palpebral fissures (due to blepharophimosis, blepharospasm, and abnormal orbital configuration), microstomia, micrognathia, myotonia, muscular hypertrophy, osteochondrodysplasia, and growth retardation. Expressivity varies and in some sibships females are less severely affected than their brothers. The sexual development of the sibs with chondrodystrophic myotonia, who are now in the mid to late second decade, has been normal. Linear growth rate accelerated during puberty but the adult height of the male is less than normal. Administration of human growth hormone had no consistent effect on the growth pattern of this boy.

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.…”

Heterogeneity in Schwartz-Jampel chondrodystrophic myotonia

“…Most cases (including the original cases [1,24] described as having ''myopathy'') had firm but hypotrophic muscles, while some patients have hypertrophic muscles [7; our case 1]. In most SJS cases studied in this respect, myotonia was not influenced by the application of curare, but in others myotonic discharges were suppressed by curare (four cases from the literature [5,9,27] and our case 2), indicating neurogenic rather than myogenic myotonia. These discrepancies might suggest heterogeneity within SJS [5,10].…”

Schwartz–Jampel syndrome: a review of the literature and case report

“…The syndrome was described for the first time in 1951 by Catel, 4 and was then described by Oscar Schwartz and Robert Jampel in 1962 5 . SJS has also been referred to as osteochondromuscular dystrophy, 6 chondrodystrophic myotonia 1,7 of the Catel–Hempel type or Aberfeld syndrome, 2 as well as “Schwartz syndrome” in the literature.…”