Cardiac Surgery-Associated Acute Kidney Injury (CSA-AKI) in Children with Congenital Heart Diseases in Southwest Nigeria

Acute kidney injury (AKI) is a major complication of open heart surgery in children with congenital heart diseases. This increases the risk of morbidity and mortality due to late diagnosis because there are no clear-cut markers for early assessment of sudden decline in renal function. The plasma concentrations of cystatin-C were measured at time intervals and compared with plasma creatinine levels in children with cardiac surgery-associated AKI (CSA-AKI). The aim was to evaluate the usefulness of cystatin-C as a biochemical marker of AKI in children undergoing cardiac surgery for congenital heart diseases.Method:This was a prospective, longitudinal study, of 40 children who had open heart surgery, on account of congenital heart diseases, at our study center, between April 2020 and June 2022. Plasma samples were assayed for cystatin-C using the enzyme-linked immunosorbent assay method, while quantification of creatinine was done using a Roche automated analyzer (Cobas C311).Result:Mean plasma concentrations of cystatin-C at 0, 4, 8, 12, 24 and 48 hours were 0.49 +/- 0.11 ng/dL, 0.75 +/- 0.19 ng/dL, 0.96 +/- 0.23 ng/dL, 0.79 +/- 0.20 ng/dL, 0.66 +/- 0.15 ng/dL, and 0.60 +/- 0.14 ng/dL, respectively, versus 48.98 +/- 11.6 mu mol/L, 59.65 +/- 13.06 mu mol/L, 63.00 +/- 16.53 mu mol/L, 64.90 +/- 17.65 mu mol/L, 68.50 +/- 19.99 mu mol/L, and 70.78 +/- 21.86 mu mol/L, respectively, of creatinine. Plasma cystatin-C peaked earlier at 8 hours compared to creatinine, which peaked at 48 hours. The ROC curve showed that cystatin-C had an AUC of 0.983.Conclusion:This study showed that cystatin-C has a better sensitivity and specificity than creatinine in predicting CSA-AKI in children who had open heart surgery for congenital heart diseases.