This is a recently reported inherited form of early onset muscular dystrophy with cataracts. Mild intellectual disability is often present but intellect may be normal in some patients.
Infants are often noted to be "floppy" at birth and notable muscle weakness begins in early childhood. Th lower limbs are often more severely involved but the weakness can stabilize somewhat. Usually gait is the most severely impacted and many adults are confined to a wheelchair. This is a degenerative muscle disease and notable wasting occurs with time. The heart is not involved but breathing muscles are leading to respiratory weakness. Mild intellectual impairment is common but normal intelligence occurs in some patients as well.
Cataracts are often noted within the first two years of life and several infants have been diagnosed with cataracts at the age of 6 months.
Other variable findings include short stature, contractures of joints, abnormal curvature of the spine and spinal rigidity, and seizures.
This syndrome results from changes (mutations) in both copies of a specific gene (autosomal recessive disorder). The parents, who are clinically normal, carry a single mutation and each child has a 25% risk of inheriting it from both parents.
The diagnosis is unlikely to be made at birth because the signs of muscle weakness and floppiness are mild and nonspecific. The progressive nature of the muscle weakness and wasting may alert the pediatrician and neurologist to a more serious progressive problem and they may wish to examine a muscle biopsy and investigate a muscle enzyme known as creatine kinase which is usually elevated in the blood.
Cataracts are also a nonspecific sign but their presence might suggest the diagnosis when the entire clinical picture is considered.
There is no effective treatment for this condition. However, physical therapy might be beneficial in selected individuals. Cataract surgery and release of contractures might improve the quality of life in certain patients. Nothing is known regarding longevity.