Acute Kidney Injury Associated with High Nephrotoxic Medication Exposure Leads to Chronic Kidney Disease after 6 Months

Objective To assess the development of chronic kidney disease (CKD) after high nephrotoxic medication exposure-associated acute kidney injury (NTMx-AKI) in hospitalized children. Study design We performed a retrospective cohort study of children exposed to an aminoglycoside for ≥3 days or ≥3 nephrotoxic medications simultaneously for the development of CKD at 6 months. Follow-up data >6 months after acute kidney injury (AKI) were retrieved from electronic health records. Outcomes in children with NTMx-AKI were compared with patients of same age and primary service distribution who were exposed to nephrotoxic medications but did not develop AKI (controls). Results One hundred patients with NTMx-AKI were assessed (mean age of 9.3 ± 6.9 years). Commonly involved services were bone marrow transplantation/oncology (59%), liver transplantation (13%), and pulmonary (13%). Pre-AKI estimated glomerular filtration rate (eGFR) was 119 ± 14.5 mL/min/1.73 m 2 (range 90-150 mL/min/1.73 m 2 ). Mean discharge eGFR was 105.1 ± 27.1 mL/min/1.73 m 2 . At 6 months after NTMx-AKI, eGFR (n = 77) was 113.8 ± 30.6 mL/min/1.73 m 2 . Sixteen (20.7%) had eGFR of 60-90, 2 (2.6%) had eGFR 150 mL/min/1.73 m 2 (hyperfiltration). Twenty-four (68.5%) of 35 patients who were assessed for proteinuria had a urine protein-to-creatinine ratio >0.3 mg/mg, and 29 (37.6%) had hypertension. Twenty-six (33.7%) patients had CKD (proteinuria or eGFR  2 ). An additional 28 (36.3%) were considered to be at risk for CKD with hypertension, eGFR between 60 and 90 mL/min/1.73 m 2 , or eGFR >150 mL/min/1.73 m 2 . CKD, hypertension, and proteinuria were more common in the AKI cohort than in controls. Conclusions Six months after NTMx-AKI, 70% of patients had evidence of residual kidney damage (reduced eGFR, hyperfiltration, proteinuria, or hypertension). Few underwent a complete evaluation for CKD. With studies showing an association between AKI and CKD, we suggest systematic comprehensive follow-up in children after NTMx-AKI.