New ultrasound screening criteria for kidney disease proposedOctober 22nd, 2008 - 4:35 pm ICT by IANS
Toronto, Oct 22 (IANS) Modification of current criteria in ultrasound screening is required for diagnosing patients with rarer kidney disorder like autosomal dominant polycystic disease or ADPKD, according to a study. The results suggest that some patients with a milder form of the disease may otherwise be misdiagnosed.
Individuals at risk for developing ADPKD are commonly screened by imaging techniques such as ultrasound. Diagnosis can also be made with a genetic test that detects mutations in the two genes that cause the disease, called PKD1 and PKD2.
To test whether this is the case, York Pei of University of Toronto, in Ontario, Canada, and his colleagues performed kidney ultrasounds and genetic tests on 577 and 371 at-risk individuals from 58 PKD1 and 39 PKD2 families, respectively.
The researchers found that current ultrasound diagnostic criteria may misdiagnose individuals with mutations in the PKD2 gene. Therefore, the investigators designed new ultrasound criteria that could accurately detect the disease in individuals with mutations in either PKD1 or PKD2 gene.
ADPKD, a genetic disorder characterised by the growth of numerous cysts in the kidneys, can lead to reduced kidney function and kidney failure. It is the most common inherited kidney disorder, occurring in one out of 500 births, and symptoms usually develop between the ages of 30 and 40 years.
However, gene-based diagnosis is expensive and detects definitive mutations in only 41 percent to 63 percent of the cases. In many clinical settings, it is rarely performed, according to a release of American Society of Nephrology.
Ultrasound screening for ADPKD is based on diagnostic criteria developed to detect cases caused by mutations in the PKD1 gene. This form of the disease is more common and more severe than the form caused by mutations in the PKD2 gene. Therefore, there may be a need for different diagnostic criteria for patients with the milder, less common form of autosomal dominant polycystic disease.
These findings will appear in January issue of the Journal of the American Society Nephrology (JASN).