Increased risk of chronic kidney disease in children with anorectal malformations

Anorectal malformations (ARM) are often accompanied by urological anomalies, which can contribute to the development of chronic kidney disease (CKD).

This study aimed to investigate the prevalence of kidney and urinary tract anomalies, as well as bladder dysfunction, and their potential impact on the development of CKD in children with ARM.

This single-center, retrospective study included 175 children with ARM, after excluding 75 children with missing data. Clinical and radiological findings and serum creatinine levels were obtained from medical records. Anorectal malformations were classified as "high" and "low" type based on the Wingspread classification, and also further classified by fistula type and sex distribution according to the Krickenbeck International Classification. CKD was defined and staged according to the KDIGO (Kidney Disease Improving Global Outcomes) guidelines.

The median age of the patients was 9.7 years, with a male-to-female ratio of 1.13:1. Among the 175 patients, 97 (55 %) had intermediate or low-type ARM, and 78 (45 %) had high-type ARM. Kidney and/or urinary tract anomalies were identified in 85 patients (48.5 %), with 63 having kidney anomalies and 71 having urinary tract anomalies. The most common urinary tract anomaly was vesicoureteral reflux (n = 58). Bladder dysfunction was observed in 56 patients (32 %). CKD was diagnosed in 30 patients (17 %); six of them were in CKD stage 5, and the remaining 24 were in stages 2-4. The development of CKD was more common in both females and males with kidney anomalies (p < 0.001), urinary tract anomalies (p < 0.001 and p = 0.002, respectively), bladder dysfunction (p < 0.001), urinary tract infection (p < 0.001), in addition females with persistent cloaca (p = 0.023) and spinal anomalies (p = 0.013). Kidney anomalies and bladder dysfunction were independently associated with the development of CKD (p < 0.001 and p = 0.046, respectively).

This study highlights that approximately half of the children with ARM had kidney and urinary tract anomalies, and one-third had bladder dysfunction. Additionally, almost one-fifth of the patients developed CKD, mostly in the early stages. Our findings also suggest that both kidney anomalies and bladder dysfunction are significant risk factors for CKD development in children with ARM.

This study emphasizes the presence of kidney anomalies, along with bladder dysfunction as risk factors for CKD. Physicians should take care to monitor and manage these risks to minimize the long-term impacts on kidney health in children with ARM.