Objectives: To determine incidence and severity of acute kidney injury (AKI) within 7 days of sepsis evaluation and to assess AKI duration and the association between AKI and 30-day mortality.
Study design: Retrospective, matched cohort study in a single-center level IV NICU. Eligible infants underwent sepsis evaluations at ≥72 hours of age during calendar years 2013-2018. Exposed infants (“cases”) were those with culture-proven sepsis and antimicrobial duration ≥5 days. Non-exposed infants (“controls”) were matched 1:1 to exposed infants based on gestational and corrected gestational age, and had negative sepsis evaluations with antibiotic durations <48 hours. AKI was defined by modified neonatal Kidney Disease Improving Global Outcomes criteria. Statistical analysis included Mann-Whitney and Chi-square tests, multivariable logistic regression, and Kaplan-Meier time-to-event analysis.
Results: Among 203 episodes of late-onset sepsis, 40 (20%) developed AKI within 7 days following evaluation, and among 193 episodes with negative cultures, 16 (8%) resulted in AKI (p=0.001). Episodes of sepsis also led to greater AKI severity, compared with non-septic episodes (P = .007). The timing of AKI onset and AKI duration did not differ between groups. Sepsis was associated with increased odds of developing AKI (aOR 3.0, 95% CI 1.5-6.2, p=0.002). AKI was associated with increased 30-day mortality (aOR 4.5, 95% CI 1.3-15.6, p=0.017).
Conclusions: Infants with late-onset sepsis had increased odds of AKI and greater AKI severity within 7 days of sepsis evaluation, compared with age-matched infants without sepsis. AKI was independently associated with increased 30-day mortality. Strategies to mitigate AKI in critically ill neonates with sepsis may improve outcomes.