Abstract
Objective Acute kidney injury (AKI) incidence is 30% in neonatal intensive care units (NICU).
AKI is associated with increased mortality and risk of chronic kidney disease (CKD)
in children. To assess follow-up and early CKD, we retrospectively reviewed outcomes
of Cincinnati Children's Hospital Medical Center (CCHMC) cohort of neonates from the
AWAKEN trial (2014).
Study Design Data from 81 CCHMC patients were extracted from the AWAKEN dataset. KDIGO (Kidney
Disease: Improving Global Outcomes) criteria for serum creatinine (SCr) and urine
output (UOP) <1 mL/kg/h, reported per 24 hours on postnatal days 2 to 7, were used
to define AKI. Charts were reviewed until May 2019 for death, nephrology consult,
AKI diagnosis on discharge summary, follow-up, and early CKD at >6 months of age (defined
as: estimated glomerular filtration rate < 90 mL/min/1.73 m2, hyperfiltration, proteinuria, hypertension, or abnormal ultrasound). Patients were
considered to have renal follow-up if they had ≥1 follow-up visit containing: SCr,
urinalysis, or blood pressure measurement.
Results Seventy-seven patients had sufficient data to ascertain AKI diagnosis. In total 47
of 77 (61%) were AKI+ by SCr or UOP criteria (20 stage 1, 14 stage 2, 13 stage 3).
Four died during their admission and five were removed from CKD analyses due to urologic
anomalies. AKI-UOP alone outnumbered AKI-SCr (45 AKI+ vs 5 AKI+ for all stages). 33%
of patients had <2 SCr measured while inpatient. Only 3 of 47 AKI+ patients had a
nephrology consult (all stage 3 by SCr) and 2 of 47 had AKI included in discharge
summary. 67% of AKI+ patients had follow-up. In total 10 of 43 (23%) AKI+ versus 12
of 25 (48%) AKI− patients had ≥1 marker of early CKD assessed after 6 months. Based
on SCr, 3 of 7 (43%) AKI+ had hyperfiltration versus 0 of 7 (0%) AKI− (p = 0.19).
Conclusion AKI is vastly under-recognized in the NICU, especially if based on SCr alone. This
leads to insufficient follow-up to ascertain renal sequelae in this high-risk population.
Key Points
-
AKI is under-recognized in high-risk neonates.
-
There is a lack of adequate follow-up.
-
Identification of AKI by SCr alone is insufficient.
Keywords
acute kidney injury - neonates - follow-up - hyperfiltration
