extremely rare autosomal recessive disorder. The disease has its onset in childhood, and progresses through three distinct stages. Stage I of the disease is characterized by a subacute encephalopathy of undefined origin that includes confusion, vomiting, and a history of febrile illness. By stage II, this progresses into acute encephalopathy with sudden loss of developmental milestones, slurred speech, loss of motor function, and development of quadriparesis or quadriplegia, along with seizures. If left untreated, the disease progresses to stage III, characterized by an akinetic mute state, which culminates in death.
MRI in patients shows specific bilateral necrosis in the head of the caudate nucleus and the putamen. Interestingly, they can be almost completely cured with the continuous administration of high doses of biotin, starting early in the disorder. In cases where this treatment is started later in the disease, some symptoms remain, such as residual paraparesis, mild mental retardation, and dystonia. To date, all patients diagnosed have been Arab in origin, having Saudi, Syrian, or Yemeni origin.