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Prevalence is estimated at around 1/25,000-30,000, with a male predominance (male to female sex ratio: 3:1).

Mean age at diagnosis is 6 years. The main clinical features are spasticity and limited movements around the mouth and throat from an early age, and brisk jaw jerks. In severe cases, the muscles of the pharynx and larynx are also involved. Epilepsy, learning difficulties and behavioral disturbances are common. Mild pyramidal tetraplegia, glue ear, recurrent respiratory infections and aspiration, and gastroesophageal reflux may be present in up to 40% of patients. WDS is associated with bilateral lesions of the corticobulbar tract. Cranial nerves VII, X, and XII are implicated.

Diagnosis is made on the basis of patient history, clinical examination and magnetic resonance imaging studies.

The main differential diagnosis is the bilateral perisylvian polymicrogyria (see this term) which manifests with severe epilepsy Clinical overlap of WDS with congenital bilateral perisylvian polymicrogyria and Foix-Chavany-Marie syndrome (see these terms) has been noted. Some authors propose that these three conditions represent a continuum.

Most cases are sporadic but several families with more than one affected member have been reported. Inheritance in these families appeared to follow an autosomal dominant pattern with variable expression and penetrance.

Management is dependent on the degree of feeding difficulties and speech problems but should include multidisciplinary approach by a pediatrician, speech therapist and educational psychologist. Children with epilepsy are treated with antiepileptic drugs.

WDS has a non-progressive course. The overall prognosis is good when nutritional problems, epilepsy and respiratory complications are properly managed.