User:Q.karimoen

Capos syndrome is an uncommon autosomal genetic disorder, which is related to a mutation in the ATP1A3-gene. This disorder reduces levels of consciousness and it also affects the muscles, but it is mostly known because it has visual impairments and hearing impairments.

Capos syndrome is short for the words cerebellar ataxia, areflexia, pes cavus, optic atrophy and sensorineural hearing loss. So far known, the syndrome is only known to affect humans.

History
The clinical Capos syndrome was first described in 1996. It was found in two siblings and their mother who suddenly started showing symptoms such as relapsing, sensorineural hearing loss, early onset cerebellar ataxia, and hypotonia. The three of them shared the main features of the syndrome, however, there were differences in the severity and the amount of the relapses. It is believed that this neurological disorder can be seen as a new ataxia “plus” syndrome. This disease is rare: so far there have been 11 case reports of patients from different families who suffered from this disease.

Symptoms
The following symptoms can be prevalent during this disease: cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss. An acute neurological deterioration can manifest from an early age on and can be  triggered by stressful episodes, for example a febrile illness. These episodes may be of periodic nature and can be accompanied by symptoms such as ataxia, acquired areflexia, ophthalmoplegia, hypotonia, weakness, lethargy, and comatose state which can be suggestive of encephalitis. The earlier named symptoms may disappear later on. Case studies also have shown that sensorineural deafness and optic atrophy may develop during or after the occurence of an acute event. The further progress is slow. There were also descriptions of slowly progressive hearing loss accompanied by acute episodes of deterioration.

Disease progression
Both age and gender do not determine whether a patient gets the syndrome or not. The first symptoms can arise in both early childhood and adulthood. The most prevalent of these first symptoms are cerebral ataxia and febrile illness. Later in life, almost all patients develop sensorineural hearing loss and optic atrophy to some degree, often accompanied by some of the other symptoms.

Causes
The CAPOS syndrome is caused by a mutation (heterozygous c.2452G > A) in ATP1A3. This mutation was found in ten affected individuals in three different families. Acute onset of ataxic encephalopathy with febrile illness in childhood, partial recovery and subsequent slow progression is what characterizes CAPOS syndrome clinically.

Treatments
All identified patients have the same heterozygous missense (variant c.2452G>A (p.Glu818Lys) in the ATP1A3-gene), encoding an ATPase (Na+ /K+ ATPase α3). We describe a large CAPOS pedigree with three generations of affected members, the first ascertained in the United States. Deafness, optic atrophy, and pes cavus were present in all three members of the family evaluated. In addition, one of the affected individuals experienced markedly worsening features during her three pregnancies and in the immediate postpartum period, a potential element of the natural history of CAPOS previously unreported.