Progeria

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at November 14, 2016
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Progeria, sometimes referred to as Hutchison-Gilford syndrome, is a progressive genetic disorder in which the aging process is accelerated. The condition is extremely rare and is believed to affect approximately 1 in every 4-8 million children around the world. Most children with progeria do not live beyond their early teens.

Contents

Definition & Facts

Progeria was first described by Dr. Jonathan Hutchinson and Dr. Hastings Gilford in the late 19th century. The name of the condition comes from the Greek word progeros, which means prematurely old. Cases of progeria have been reported around the world across all ethnic groups, and the condition appears to affect males and females equally.

Children with the disease are susceptible to conditions typically associated with aging, including high blood pressure, angina, stroke, and heart failure. Most children with the condition appear healthy at birth but start to show characteristics of the disease around the age of 2. 

Symptoms & Complaints

Most children with progeria show symptoms of failure to thrive, including a loss of body fat, poor weight gain, and slow growth. The skin will appear aged, and scleroderma, or hardening of the skin, may develop on the extremities and trunk.

Regardless of ethnicity, children with progeria exhibit distinctive facial characteristics, including a narrow face with a small jaw, a beak-like nose, a disproportionately large head, and prominent eyes. The ears may protrude, veins are often visible along the scalp, and the voice tends to be high-pitched.

Hair loss and loss of eyebrows, a condition known as alopecia, is also common. Children with progeria frequently experience tooth abnormalities, joint stiffness, and fragile bones. Most children with the disease succumb to the effects of cardiovascular disease, including atherosclerosis, heart attack, and stroke. Progeria has no effect on brain development or the immune system.

Causes

Progeria is the result of a mutation in a single gene called lamin A, or LMNA gene. The gene produces a protein called lamin A that serves as scaffolding that binds the nuclei of cells together. The defect causes the gene to produce an abnormal protein called progerin, which makes the nucleus of the cell unstable. The protein may also cause telomere dysfunction. Telomeres are protein buffers located at the ends of chromosomes and are believed to impact cellular aging.

Everyone makes a certain amount of progerin, and it is believed that that the protein is at least partly responsible for conditions associated with aging, such as atherosclerosis. Children with progeria produce much more progerin than otherwise healthy individuals. The genetic defect that causes progeria is not inherited, which means that it cannot be passed down through families.

It is believed that the condition is caused by a chance mutation in a single egg or sperm prior to conception. There are other progeria-like syndromes that are inherited and associated with accelerated aging and premature death. These include Wiedemann-Rautenstrauch syndrome and Werner syndrome. In Wiedemann-Rautenstrauch syndrome, the progeria-like symptoms begin in utero and are apparent at birth. The onset of Werner syndrome typically occurs in the late teens or early adulthood. 

Diagnosis & Tests

The physical characteristics of progeria are quite distinctive and can normally be identified during a routine checkup. Since children with progeria typically show signs of failure to thrive, a physical exam may be performed to compare the child’s height and weight to children of similar age. Pulse and blood pressure will be monitored to identify potential cardiovascular disorders.

Since cataracts and hearing loss are common with progeria, vision tests and hearing tests may be necessary. If a family physician or pediatrician suspects that a child has progeria, they will normally refer the child to a medical geneticist who can confirm the diagnosis. A blood test is available to test for the specific genetic mutation that causes progeria. 

Treatment & Therapy

Currently, there is no cure for progeria. Treatment is aimed at managing symptoms and delaying certain complications. Many of the medications and therapies are the same as those used to treat conditions in older adults. Low-dose aspirin therapy and anticoagulants may be used to reduce the risk of heart attack and stroke. Statins may be prescribed to control cholesterol levels and slow the development of cardiovascular disease. In certain circumstances, growth hormone therapy may help the child reach a more normal height and weight.

Dental problems are common with progeria. Extractions may be needed to prevent tooth overcrowding and to ensure proper tooth alignment. Physical therapy and occupational therapy may improve joint function and alleviate arthritis symptoms.

Angioplasty or coronary bypass surgery may help delay the progression of heart disease. Clinical trials are underway to identify new treatments for progeria. One promising area of research involves farnesyltransferase inhibitors, also known as FTIs. These drugs were originally developed to treat cancer but may be effective in repairing cell damage caused by progeria. 

Prevention & Prophylaxis

There is no way to prevent progeria. The chances of having a child born with the condition are approximately 1 in 4 to 8 million. Parents with one child born with the condition have a 2 to 3 percent chance of having a second child with the disease. There are prenatal tests available to check for the presence of a defect in the LMNA gene.

The physical effects of progeria can be debilitating. The knowledge that the disease shortens life span can also be emotionally difficult on both the patient and their family. Building a support network of health care providers, family, friends, and others who are going through similar experiences is essential.

Parents can take the following steps to make their child more comfortable at home.

  • Encourage the child to drink plenty of fluids since dehydration can be especially dangerous in children with progeria.
  • Prevent malnutrition by encouraging the child to eat small, frequent meals.
  • Provide opportunities for physical activities appropriate for the child’s level of functioning.
  • Progeria can make skin sensitive to the sun, so it is important to use a high SPF sunscreen when outdoors. 
  • Provide opportunities for learning at an age-appropriate level, especially if physical limitations prevent the child from attending school.
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