(44) Development and Expansion of a Biorepository for Critically Ill Children with Acute Kidney Injury

Background: Acute kidney injury (AKI) is common in critically ill children and is associated with poor outcomes including mortality, length of stay, and chronic kidney disease. Despite growing studies of AKI, biomarkers for identification and prognostication are not routinely included. This is often due to difficulties obtaining samples, especially with retrospective research questions.

Objectives: We describe our experience developing and expanding a prospective biorepository of biologic samples for children with AKI admitted to the neonatal, pediatric, or cardiovascular intensive care units (NICU, PICU and CVICU) at a single center quaternary pediatric hospital.

Design/Methods: Children with AKI are identified in real time through an automated electronic health record alert for the NICU, PICU, and CVICU. Patients aged < 18 with AKI by KDIGO serum creatinine criteria (1.5x baseline) on laboratory tests are eligible for inclusion. Demographic and clinical data are obtained. Urine and blood are collected on day 1-3 of AKI event. Urine is collected by bedside nurses using standardized collection methods. Scavenged blood available after clinically indicated laboratory testing is collected from the hematology department and plasma or serum are extracted. Processed samples are stored at -80°C for biomarker analysis and future studies. As urine and blood are deemed medical waste, the IRB approved a waiver of consent, facilitating sample collection.

Results: In the 6 months since launch, we have included 127 subjects in the biorepository. Each subject has at least one urine or blood sample processed and stored for future analysis. Of these patients, 40% were in the NICU, 36% in the PICU, and 24% in the CVICU (Fig 1a). Since launch, 143 urine and 210 blood samples have been processed. Urine samples are more commonly available in the NICU, with 76 urine samples from the NICU, 31 from the PICU, and 36 from the CVICU (Fig 1b). From the NICU, 44 blood samples were gathered, the PICU had 94, and the CVICU provided 72 samples (Fig 1c).

Conclusion: Identification of AKI patients and procurement of biospecimens in critically ill children. With consistent collaboration with nursing and laboratory staff, an expansive biorepository of biomedical samples can be collected for future biomarkers research. A biorepository dedicated to AKI in critically ill pediatric patients will facilitate future research in AKI through tracking of patient outcomes and detailed clinical phenotypic information.