Zellweger Syndrome

Zellweger syndrome is an inherited genetic disorder affecting infants.

It belongs to a family of disorders called peroxisome biogenesis disorders (PBD).

Causes

During fetal development, certain gene mutations negatively influence brain development and the formation of myelin, the substance that insulates nerve cells and enables effective nerve conduction.

After birth, the same gene mutations mentioned above reduce the levels of peroxisomes. Peroxisomes, affectionately known as the "garbagemen of cells", are intracellular structures that break down toxic substances in the liver, kidneys, and brain. As a result of this decline in peroxisomes, high levels of iron and copper build up in the aforementioned tissues and produce deleterious effects on the developing infant.

Risk Factors

There are no known risk factors for Zellweger syndrome.

Signs and Symptoms

Symptoms of iron and copper build-up in the aforementioned tissues include:

• liver abnormalities (such as enlarged liver and jaundice)
• facial deformities (such as a high forehead, underdeveloped eyebrow ridges, and deformed ear lobes)
• brain abnormalities (such as mental retardation and seizures)
• eye/ear abnormalities (such as glaucoma, retinal degeneration, and impaired hearing.
• muscle tone abnormalities (such as inability to move, and may not be able to suck or swallow)

Treatment

Since the genetic abnormalities that cause Zellweger syndrome are caused during fetal development, treatments after birth are limited to symptomatic control.

Prognosis

The prognosis for Zellweger syndrome is very poor.

Most infants do not survive past six months of age. Causes of death are usually respiratory distress, gastrointestinal bleeding, or liver failure.

References

External Links

• National Institute of Neurological Disorders and Stroke
• Gene Reviews
• Cleveland Clinic