Say-Meyer syndrome: A new case with magnetic resonance imaging of the brain, cardiac abnormality and X-linked dominant inheritance pattern

Abstract

We report a new case of Say-Meyer syndrome, a rare X-linked disorder characterized by metopic suture synostosis, a high-arched palate, short stature and delayed development. Proband was a nine-month-old boy admitted to our hospital for evaluation of failure to thrive and global developmental delay. Genetics evaluation revealed: marked growth failure; microcephaly; a closed anterior fontanelle; hypotelorism; esotropia; long eyelashes; a high, narrow palate; distal hypospadias. Neurologic examination demonstrated diffuse hypotonia, diminished deep tendon reflexes, and excessive head lag. A search of the London Dysmorphology and POSSUM databases suggested Say-Meyer syndrome as the unifying diagnosis.

This infant's medical history was complicated by prematurity at 32 weeks gestation, postnatal supplemental oxygen requirement and abnormal heart sounds. Cardiac evaluation identified Ebstein anomaly of the tricuspid valve as the etiology of his cardiac problems requiring ongoing medical surveillance.

Magnetic resonance imaging (MRI) of the brain revealed a decreased volume of white matter with associated atrophy. The brain stem was small. The corpus callosum was thin and the genu and rostrum were not visualized. Increased signal intensity in the periventricular regions suggested periventricular leukomalacia. The ventricles were enlarged. Skull radiographs showed a decreased interorbital distance and a sclerotic metopic suture.

X-linked recessive inheritance has been described. The infant's mother attended special education classes. She had marked hypotelorism, a long face, a high-arched palate, and a thin body habitus.

This case of Say-Meyer syndrome includes the first report of brain MRI findings and a previously unreported cardiac defect. Clinical features noted in the mother of this infant that suggest that Say-Meyer syndrome may be an X-linked dominant disorder with variable penetrance rather than an X-linked recessive disorder.