Alpers' disease is a neurological condition which has several names like Alpers-Huttenlocher syndrome (AHS), alpers' syndrome, progressive infantile poliodystrophy and progressive sclerosing poliodystrophy. Alpers' Disease is a progressive condition which causes degeneration of the central nervous system, especially degeneration of the gray matter. It is a genetic mutation-related disorder in which the POLG gene gets mutated.
What is Alpers' Disease?
Alper's disease is a condition that arises due to the depletion of the mitochondrial DNA, leading to progressive degeneration of the central nervous system. The depletion of the mitochondrial DNA occurs due to the mutation in the mitochondrial DNA polymerase POLG gene. Alpers' disease is characterized by dementia, continuous seizures and liver failure. These symptoms of Alpers' disease usually appear quite later than the onset of the condition, with a gap of weeks to years. The severity of Alpers' Disease often results in the inability to perform routine tasks like walking, sitting feeding self. Apart from movement headaches, sleepiness, lethargy, irritability as well as reduced vision and hearing are experienced.
Alpers' disease occurs primarily due to the inheritance of autosomal recessive traits from carrier parents, with a probable risk of twenty five percent.
Symptoms of Alpers' Disease
The symptoms that mark the onset of Alpers' Syndrome are:
- Dementia or loss of cognitive functioning
- Severe liver disorders including cirrhosis and jaundice
- Seizures which can be convulsions as well as epileptic
- Spasticity or enlarged muscle tone with enhanced reflexes
- Vision impairment
- Impaired functioning of digestive system
- Difficulty in proper functioning of heart or cardiomyopathy.
Prevalence Rate of Alpers' Disease
Alpers' disease is known to have an incidence rate of one in a 100000 to 250000 of population with the development of symptoms within two years for over eighty percent of the population whereas the remaining twenty percent of the population develop symptoms over years up to twenty five years of age.
Prognosis and Survival Rate of Alpers' Disease
The outlook of Alpers' disease is quite poor as the survival rate of the disease ranges between a few months to a few years after the onset of the symptoms. The treatments available only check the symptoms and do not contribute to the cure of the disease. The common reasons behind the death of the patients are accounted by seizures, liver failure and cardiomyopathy.
Causes of Alpers' Disease
Alpers' disease results due to the mutation of the POLG polymerase gene which is responsible for the production of energy with the mitochondria. This energy is then further utilized to maintain the cells of the body especially maintaining of the healthy brain cells. When the mutation exists, there is a decrease in the mitochondrial DNA, which further causes low levels of cellular energy resulting in the degeneration of the cells like the progressive degeneration of the gray matter as well as the liver failure.
Pathophysiology of Alpers' Disease
The mitochondrial DNA polymerase is encoded by the POLG gene. When mutation occurs, the amounts of mitochondrial DNA gets depleted leading to oxidative phosphorylation defect in mitochondria. This defect results in the degeneration of brain cells, liver failure and encephalopathy.
Risk Factors of Alpers' Disease
The prime risk factor for Alpers' disease is the family history because, the disease occurs due to inheritance of the mutation in the POLG gene.
Complications of Alpers' Disease
The complications associated with Alpers' disease are quite serious. Some such complications that may arise owing to the condition are:
- Loss of vision due to damaged optic nerve
- Severe damage of the brain
- Epileptic fits
- Liver failure
- Failure of cardiorespiratory system.
Diagnosis of Alpers' Disease
The diagnosis of Alpers' disease can be done when the symptoms are observable. Post the appearance of the symptoms, the diagnostic procedures followed are:
- Medical History Assessment: A clinical analysis is conducted to obtain a detailed patient history as well as physical fitness is evaluated.
- Brain Scan to Diagnose Alpers' Disease: The specialized imaging of brain using MRI, CT scan are utilized to study the extent of degeneration occurring in the cerebral cortex as well as other parts of the brain.
- Diagnosing Alpers' Disease with Electroencephalography: EEG is used to study the electrical impulses within the brain. In case of Alpers' disease, the electrical activity of the brain is abnormal due to presence of seizures.
- Liver Function Tests: These tests include the checking for coagulation, alanine aminotransferase, bilirubin as well as ammonia and glucose levels to check for the extent of liver damage. Ultrasound is also done to check for abnormalities in liver for patients with Alpers' disease.
- Electrocardiogram: The ECG is conducted to rule out the possibility of cardiomyopathy.
- Audiogram: An audiogram is conducted to check for impairment of hearing ability in patients with alpers' disease.
Treatment & Management of Alpers' Disease
There are no possible treatments to stop the Alpers' disease; however, the only way is to control the symptoms.
- Medications to Manage Alpers' Disease: Medications can be prescribed to relieve pain, muscle spasms, treat infections and check the seizures. These medicines include:
- Sedative Medications: Sedative medications for Alpers' disease are prescribed to treat anxiety and discomfort.
- Anticonvulsants: These are prescribed to treat the seizures, when sedative medication fails to provide the required relief. Valporate should not be taken to reduce the risk of liver failure.
- Physiotherapy to Manage Symptoms of Alpers' Disease: Physiotherapy is advised to relieve the effect of spasticity, to help in seating posture and exercising of limbs.
Prevention of Alpers' Disease
There are no defined preventive measures for Alpers' disease except for prenatal diagnosis of the condition through genetic testing. This can help in better insight of the risks and possibilities for treatment.
Alpers' disease is a defect of mitochondrial dysfunction, which is inherited as an autosomal recessive disorder. The condition has three clear symptoms which are dementia, severe liver diseases especially liver failure and spasticity. The symptoms of Alpers' disease do not appear immediately, but come up after a few months and take up to years to appear fully. Alpers' disease is a progressive one and has no possible treatment. The only available treatments are to check the symptoms of Alpers' disease and provide relief from them.