Spastic Paraplegia 46

Background and History: 

Spastic paraplegia refers to a group of neurological disorders with prominent symptoms of stiffness in the arms and legs.  There are numerous types, most of them hereditary, distinguished from each other by the types of symptoms and age of onset. The degree of disability depends on what brain structures are involved.  Virtually all are progressive disorders.

Spastic paraplegia 46 has been reported in a male and 4 females in a Tunisian family.

Clinical Correlations: 

Affected individuals notice some weakness and stiffness in their legs between the ages of 2 and 20 years.  These symptoms worsen slowly although most patients are still mobile with some disability into the fourth decade of life.  The arms are variably involved as well with hyperactive reflexes and perhaps some difficulty with fine movements.  Speech may be slurred and bladder difficulties can be a feature.  The feet are sometimes deformed (pes cavus or pigeon-toed) and the spine may be abnormally curved.

Cataracts are usually present at birth.

Early mental development seems to be normal but reasoning slowly becomes more difficult.

 

Genetics: 

This condition usually occurs when both members of a gene pair are changed (mutated).  The inheritance pattern is autosomal recessive.  The parents in this family are related and each carry one gene mutation, but are clinically normal.  Generally one can expect that 25% of their children will have this disorder.  The gene change (mutation) has so far not been identified but is located on chromosome 9.

Diagnosis and Prognosis: 

The diagnosis is usually made by a neurologist.  However, in this disorder the lens opacities (cataracts) may be diagnosed at birth by a pediatrician or ophthalmologist.  The MRI may show some loss of tissue in certain areas of the brain but this is nondiagnostic.  Nothing is known about longevity but spastic paraplegia is a progressive disease leading to increasing disability.  Speech and physical therapy may have some benefits

No treatment is known for the neurological condition.  Surgical cataract removal may be an option but has not been reported in this condition.

Additional Information
Inheritance/Pedigree: 
Autosomal recessive