There is no cure for Zellweger syndrome, nor is there a standard course of treatment. Infections should be guarded against to prevent such complications as pneumonia and respiratory distress. Other treatment is symptomatic and supportive. The prognosis for individuals with Zellweger syndrome is poor. Death usually occurs by 6 months of age, and may be caused by respiratory distress, gastrointestinal bleeding, or liver failure.
The most common features of Zellweger syndrome include an enlarged liver, high levels of iron and copper in the blood stream, and vision disturbances. Some affected infants may show prenatal growth failure. Symptoms at birth may include a lack of muscle tone, an inability to move and glaucoma. Other symptoms may include unusual facial characteristics, mental retardation, seizures, and an inability to suck and/or swallow. Jaundice and gastrointestinal bleeding may also occur.
Named after Hans Zellweger, a former professor of Pediatrics and Genetics at the University of Iowa who researched the disease.[4]
The disorder is one of three peroxisome biogenesis disorders which are also known as the Zellweger spectrum. The other two diseases are neonatal adrenoleukodystrophy (NALD), and infantile Refsum disease (IRD)[2][3]
Very long chain fatty acids are generally found in the central nervous system (brain and spinal cord) and the peroxisomes of these cells can not import the necessary degradative proteins for B-oxidation to occur.
Zellweger syndrome is one of a group of genetic disorders called peroxisomal diseases that affect brain development and the growth of the myelin sheath, the fatty covering—which acts as an insulator—on nerve fibers in the brain.
It is characterized by an individual’s inability to beta-oxidize very-long chain fatty acids in the peroxisomes of the cell, due to a genetic disorder in one of the several genes involved with peroxisome biogenesis.
Several peroxins are associated with Zellweger syndrome, including PEX1, PEX2, PEX3, PEX5, PEX6, PEX12, PEX14, and PEX26.[1]
Zellweger syndrome, also called cerebrohepatorenal syndrome is a rare, congenital disorder (present at birth), characterized by the reduction or absence of peroxisomes (cell structures that rid the body of toxic substances) in the cells of the liver, kidneys, and brain.
African Americans have the highest rates of Wilm’s tumor. Females are also more likely than males to develop the tumors. Most instances of cancer occur among children under the age of 5.
Once a kidney tumor is found, surgery can find out whether or not the tumor is cancer. A sample of tissue from the tumor is sent to a pathologist, who looks at it under a microscope to check for signs of cancer. If the tumor is only in the kidney, it can be removed along with the whole kidney (a process called nephrectomy). If there are tumors in both kidneys or if the tumor has spread outside the kidney, a piece of the tumor will be removed. Children 16 years old or older have higher mortality rates within their stages. This is due to them being treated less aggressively and consistently.
Staging is determined by combination of imaging studies, and pathologic findings if the tumor is operable (adapted from www.cancer.gov). Treatment strategy is determined by the stage:
Mutations of the WT1 gene on chromosome 11 are observed in approximately 20% of Wilms tumors.[3][4] At least half of the Wilms tumors with mutations in WT1 also carry mutations in CTNNB1, the gene encoding the proto-oncogene beta-catenin.[5]
A gene on the X chromosome, WTX, is inactivated in up to 30% of Wilms tumor cases, according to research published in 2007.[6]
Most cases do not have mutations in any of these genes.[7]