Serum Chloride Trajectories and Acute Kidney Injury in Children With Diabetic Ketoacidosis

OBJECTIVES: To characterize serum chloride (Cl) burden during diabetic ketoacidosis (DKA), examine associations between Cl metrics and creatinine-defined acute kidney injury (CDAKI) and hospital length of stay (LOS), and to assess the relationship between initial beta-hydroxybutyrate (BHB) and initial serum creatinine (Scr). METHODS: We conducted a retrospective cohort study of children 1 to 20 years old with new-onset or established type 1 diabetes mellitus hospitalized for DKA from July 1, 2016, through July 31, 2022. Time-stamped serum electrolytes and renal function studies measured every 4 hours until DKA resolution. Multivariable logistic regression and time-to-event analyses evaluated associations across peak Cl, Cl normalization, CDAKI, incident CDAKI, and hospital LOS. RESULTS: A total of 364 patients accounting for 852 DKA encounters were included (mean age 13.3 ± 4.7 years, 52% male). The median baseline Cl was 105 mEq/L (IQR, 100-109) and the peak Cl was 118 mEq/L (IQR, 114-124). The median time to normalization was 50.4 hours. Additional normal saline boluses were independently associated with 37% lower hazard of Cl normalization (HR, 0.63; 95% CI, 0.46-0.87). Higher peak Cl was independently associated with CDAKI and incident CDAKI. CDAKI was in turn associated with longer hospitalization. Initial BHB was positively associated with initial Scr (Pearson r = 0.37; Spearman rho = 0.42; both P < .001). CONCLUSIONS: Hyperchloremia is common during pediatric DKA treatment and is associated with CDAKI and longer hospitalization. Saline boluses were associated with chloride burden. Because initial BHB correlated with initial Scr, CDAKI at presentation should be interpreted cautiously. These findings highlight the need for prospective studies on chloride-sparing strategies in pediatric DKA.