Morbidity in children with major kidney anomalies: a European population-based study

Knowledge about the prognosis for children born with congenital anomalies is important for counselling parents after a prenatal diagnosis. Nine population-based European Congenital Anomaly registries provided data on all children born 1995-2014 diagnosed with congenital hydronephrosis, multicystic kidney disease (MCKD), or posterior urethral valves (PUV) and on reference children from the same populations. Data up to 2015 on prescriptions, hospital diagnosis, and surgical procedures up to the 10th birthday were obtained by linkage to prescription and hospital databases. The study included 5624 children diagnosed with congenital hydronephrosis, 1314 with MCKD, and 414 with PUV. Children with hydronephrosis or MCKD were 13 times more likely to have prescriptions for antihypertensives compared to reference children before 10 years of age. Around 3% of children with congenital hydronephrosis or MCKD had a diagnosis of kidney failure at the age of 5 years; however, only 1% had a kidney transplantation by the age of 5 years. For children with PUV, 18.3% had a diagnosis of kidney failure and 5% had a kidney transplantation by the age of 5 years.

Children born with congenital hydronephrosis and MCKD generally have a low absolute risk of developing kidney failure. Children with PUV have much higher morbidity, with 1 in 5 (18.3%) being diagnosed with kidney failure before the age of 5 years. It is important to monitor these children closely in early childhood in order to prevent or delay kidney failure.

• Congenital kidney anomalies are a leading cause of pediatric end-stage kidney disease. Children with hydronephrosis, MCKD, and PUV have increased morbidity, but long-term data on medication use and kidney outcomes are limited.

• This population-based study shows a low absolute risk of kidney failure in children born with hydronephrosis or MCKD but a high relative risk. PUV has high morbidity, with 1 in 4 developing kidney failure by age 10. Antibiotic use is high in early childhood, and antihypertensive use increases with age.