Wadia-Swami Syndrome

At a glance

This is a medical disorder part of a larger group of spinocerebellar degeneration syndromes. Clinically, it is characterized by abnormal eye movements described as absent rapid saccades (scanning) and abnormally slow pursuit (tracking). Individual affected with this syndrome usually die within 10 years of the onset of symptoms. Autosomal dominant cerebellar ataxias are a heterogeneous group of disorders. Progressive cerebellar ataxia is the primary feature. The infantile onset is characterized by neonatal hypotonia, developmental delay, and severe dysphagia.

Synonyms

Spinocerebellar Atrophy II Syndrome; Olivopontocerebellar Atrophy Holguin Type Syndrome; Olivopontocerebellar Atrophy II Syndrome; OPCA2; Spinocerebellar Cuban Type Ataxia Syndrome; Cerebellar Degeneration Slow Eye Movements Syndrome.

History

This disorder was first described in 1971 by Noshir Hormusjee Wadia (1925-2016), an Indian Neurologist, and R. K. Swami also an Indian Neurologist.

Incidence

In the vicinity of Holguin in northeastern Cuba (neighboring the Guantanamo Naval Base), the prevalence was estimated at a frequency of 41:100,000 for the inherited dominant olivopontocerebellar atrophy form that is believed to occur in individuals of Spanish ancestry. The high prevalence is believed to be the result of founder effect. The prevalence of SCA2 is significantly higher in the Caucasian population (14%) when compared to the Japanese population (5%).

Genetic inheritance

Rare disease with autosomal dominant inheritance (also possibly an autosomal recessive form). This Spinocerebellar Ataxia Type 2 (SCA2) is caused by an expanded CAG trinucleotide repeat in the gene encoding ataxin-2 (ATXN2 repeat expansions have been reported).

Clinical aspects

Slowing of all eye movements is believed to be caused by a brain stem lesion of the paramedian pontine reticular formation. Clinical features include an abnormal accompanying movements of head and neck; spinocerebellar degeneration with abnormal gait (ataxia); progressive intellectual impairment, extrapyramidal dysfunction, and peripheral neuropathy. Skeletal abnormalities can occur. Muscle biopsy shows nonspecific mitochondrial abnormalities. Magnetic resonance imaging studies of the brain show a significant degree of cerebellar and brain stem atrophy. Death occurs within 10 years of onset.

Anesthetic considerations

It is recommended to evaluate carefully the neurological function (clinical, EEG, CT/MRI) and muscular condition for the presence of myotonia. Careful intraoperative positioning is needed.

Pharmacological implications

There are no specific pharmacological considerations other than those that might be associated with other underlying medical conditions associated with this medical condition.

Other condition to be considered

• ☞Louis-Bar Syndrome (Ataxia-Telangiectasia Syndrome; AT; Cerebello-Oculocutaneous Telangiectasia Syndrome; Immunodeficiency Ataxia Telangiectasia Syndrome): Complex genetic neurodegenerative disorder with an onset of symptoms during infancy or early childhood. This medical condition is characterized by ataxia, telangiectasia (reddish lesions of the skin and mucous membranes), and cellular and humoral immunodeficiency. ...