Renal agenesis and dysgenesis: are they increasing?

Area of Science:

• Pediatric Nephrology
• Birth Defect Epidemiology
• Public Health Surveillance

Background:

• The Birth Defects Monitoring Program (BDMP) of the Centers for Disease Control (CDC) has observed an increasing trend in the combined birth prevalence of renal agenesis and dysgenesis.
• It remains unclear whether this trend reflects a true increase in these conditions or changes in diagnostic, coding, or surveillance practices.

Purpose of the Study:

• To investigate the observed increase in the birth prevalence of renal agenesis and dysgenesis.
• To determine the specific contributions of renal agenesis versus renal dysgenesis to the overall trend.
• To identify potential factors influencing the observed changes over time.

Main Methods:

• Review of medical records for 1,404 infants (84% of identified cases) within the BDMP diagnosed with renal agenesis or dysgenesis.
• Analysis of autopsy-confirmed cases of bilateral renal agenesis and dysgenesis from 1970-1982.
• Assessment of diagnostic information and detection methods (autopsy vs. other procedures).

Main Results:

• The combined birth prevalence of renal agenesis and dysgenesis appears to be increasing.
• Autopsy-confirmed bilateral renal agenesis rates fluctuated, while bilateral renal dysgenesis showed a steady annual increase of 0.2 cases per 100,000 births (P < 0.001).
• Unilateral cases constituted 17% and were primarily detected via autopsy.

Conclusions:

• The observed increase in combined renal agenesis and dysgenesis is primarily attributed to a rising prevalence of renal dysgenesis.
• Further analytical studies are required to identify potential maternal risk factors associated with the increasing incidence of renal dysgenesis.