Alpers' Disease Health Article

Definition

Alpers' disease is an early-onset, progressive neurological degenerative disease that severely affects the brain and liver. In the familial (inherited) form of the disorder, it is transmitted as a recessive condition, which means that parents are unaffected, but both are carriers. Carrier parents have a 25% risk of having their biological child affected with Alpers' disease.

Description

Alpers' disease was first described by the late neurologist Alfons Maria Jakob (1884–1931). The disease was characterized and published by Bernard Jacob Alpers, Erna Christensen, and Knud Haraldsen Krabbe; thus, Alpers' disease is also known as Christensen's disease or Christensen-Krabbe disease. Additionally, the disease is known as progressive sclerosing poliodystrophy. Alpers' disease afflicts children and is eventually fatal. Degeneration in cognitive processes (reasoning ability) and muscular involvement caused by the disease is unrelenting and relatively rapid. Physically, children with Alpers' disease lose control of their muscle movements. The ramifications of this disorder can significantly affect the emotional state of the person with Alpers' disease, along with family members caring for them.

Demographics

Alpers' disease is a rare disorder. Due to complications related to the diagnosis of Alpers' disease, it is difficult to estimate how often it occurs in the population. Both genders are affected with equal frequency.

Causes and symptoms

Children with Alpers' disease usually develop symptoms between the ages of three months and five years old. Initially, the first symptom early in life is seizures (convulsions). These children tend to be hypotonic (unable to achieve normal muscle tone) and their limbs seem to be stiff. This is usually followed by the failure to reach cognitive and developmental milestones. Mental retardation is progressive in these children.

Among the most devastating features of this disorder is the progressive dementia. In children with Alpers' disease, mental deterioration can occur rapidly. The pathological nature of the defect involves an area of the brain called the cerebrum in which a specific part (the gray matter) is affected. Spastic quadriplegia (inability to use and control movements of the arms and legs) can develop in the later stages of the disorder. Blindness is also observed, and this is usually due to a condition called optic atrophy. In optic atrophy, the optic nerve degenerates, resulting in the inability to process visual information from the eye to the brain.

The liver is also affected. Liver conditions that these children experience are jaundice or complete liver failure in more severe cases. Researchers at the National Institutes of Health (NIH) consider that children with Alpers' disease are often misdiagnosed as having childhood jaundice or liver failure. This is due to the problems associated with making a diagnosis in living patients.

Currently, the specific mechanism, whether genetic, environmental, or both, that causes this disease is unknown. Scientists assume that Alpers'disease is caused by an underlying metabolic defect. Mutations in the DNA of the mitochondria (DNA that is a separate genome from the nucleus) have been associated with this disorder. The mitochondria functions to produce energy to tissues and is particularly important for tissues such as the brain.