The First Gap in Life-Course CKD Care: Kidney Follow-up after Neonatal Intensive Care Unit Discharge

CK care depends on pathways that connect risk recognition, evaluation, follow-up, and specialist input. Although CKD is often recognized later in life, CKD risk may originate at birth in infants born preterm or with low birth weight. These infants may encounter the first gap in the life-course CKD care pathway at neonatal intensive care unit (NICU) discharge, when early-life kidney risk should be linked to longitudinal follow-up. We aimed to describe post-discharge kidney follow-up practices for these infants in Japan and identify gaps among routine care, current evidence, and recent guidance.

We conducted a nationwide cross-sectional survey of neonatologists and pediatric nephrologists in Japan. Mailed invitations allowed web or paper responses. The survey assessed criteria used to identify infants at increased CKD risk, current and preferred approaches to kidney follow-up, and perceived barriers. Descriptive analyses included specialty comparisons.

Responses from 213 neonatologists and 137 pediatric nephrologists were analyzed, yielding response rates of 52% and 69%. Criteria for identifying infants at increased CKD risk differed by specialty. Neonatologists most commonly used a gestational age threshold of <28 weeks, whereas pediatric nephrologists more often selected thresholds between 28 weeks and <34 weeks. Among neonatologists, 11% did not consider prematurity alone, and another 11% did not consider low birth weight alone to be CKD risk factors; the corresponding proportions among pediatric nephrologists were 4% for both. Only 23% of neonatologists reported an institutional post-discharge follow-up protocol or manual for preterm or low-birth-weight infants, and 7% reported implementing kidney follow-up for all patients. Although 98% of pediatric nephrologists considered post-discharge kidney follow-up necessary, implementation remained limited.

Long-term kidney follow-up for children born preterm or with low birth weight remains insufficiently established in Japan. A shared care pathway across neonatology and pediatric nephrology from NICU discharge is needed.