Hypertonia and the cat-cry syndrome

Scoliosis in cat cry syndrome

BACKGROUND

Cat cry syndrome is an autosomal disease accompanying abnormal deletion of chromosome 5 and occurs in only 1 of 50,000 neonates. Scoliosis has been reported as a skeletal complication in cat cry syndrome. The characteristics and causes of scoliosis in this rare syndrome are unknown. The purpose of this study was to present the characteristics of scoliosis in cat cry syndrome and to speculate on its causative mechanisms.

METHODS

We report on 11 cases (5 boys and 6 girls) of cat cry syndrome. Detailed investigations of scoliosis, as well as physical and imaging examinations, were performed to characterize scoliosis and its causes. Average age at initial diagnosis of scoliosis was 4.3 years, and average age at final examination was 11.8 years.

RESULTS

The incidence of scoliosis was as high as 73% (8/11). Most cases show a single right thoracic curve. Of the 8 patients with scoliosis, 3 patients who had increased muscular tone showed marked progression of scoliosis with growth.

CONCLUSIONS

Muscular hypertonia may play a key role in the progression of scoliosis in cat cry syndrome.

The Cri du Chat syndrome: epidemiology, cytogenetics, and clinical features

Data for 331 cri du chat cases, including 34 Danish probands, are reviewed. The incidence nad the prevalence among the mentally retarded population amounted to 1/45,000 and 1.5/1000, respectively. No striking association with prenatal events, parental ages, or birth order could be demonstrated. There was a significant excess of females. Parental translocations were present in slightly more than 10% of the families, while more rare cytogenetic aberrations (mosaicism, rings, and de novo translocations) accounted for less than 10% of all cases. The phenotypically relevant segment has been narrowed down to the midportion of the 5p15 band. Clinical, radiologic, and dermatoglyphic features are summarized and discussed, with special attention to the abnormal cry, which persists in many older probands, and to developmental abnormalities. No obvious correlation could be detected between clinical features and the localization of the deletion. No marker locus has yet been assigned to the short arm of chromosome 5. Treatment and prevention are briefly discussed.