A-088 Extending the Stability of NGAL Reagents: A Cost-Effective Approach to Enhanced AKI Management in Pediatric Care

Abstract Background Acute kidney injury (AKI) is defined by a rapid decline in kidney function and is a leading cause of extended hospitalizations and increased morbidity. For effective intervention and to mitigate the risk of progression to chronic kidney disease (CKD), early detection of AKI is crucial. Although creatinine is the most widely used marker for assessing AKI, studies have shown that its levels often rise after significant kidney damage has occurred. Consequently, novel biomarkers such as insulin-like growth factor-binding protein 7 (IGFBP-7), tissue inhibitor of metalloproteinases-2 (TIMP-2), and neutrophil gelatinase-associated lipocalin (NGAL) have emerged. These markers have demonstrated superior efficacy in the early detection of AKI, allowing for more timely intervention and management. NGAL, in particular has been shown to correlate well with pediatric AKI. However, despite its good performance, NGAL remains underutilized in routine clinical practice, partly due to the assay costs and assay maintenance that can be difficult for 24/7 laboratories to implement. NGAL reagents are stable for only 28 days at 2-8°C after opening, significantly increasing the cost of maintaining the current assay for patient management. Thus, implementing cost-effective strategies for utilizing the NGAL reagent, while ensuring optimal AKI management in pediatric patients, is critically needed. In this study, we aimed to assess the stability of our NGAL reagent beyond the manufacturer-defined 28-day limit. Methods Our experimental design involves measuring NGAL in patient urine samples and controls on days 1, 28, 42, 56, 70, 84, and 98. We selected low, medium, and high samples that roughly span our current measurable range. Each sample will be tested in duplicate with both fresh reagent and reagent stored beyond the 28-day threshold. We will analyze concentration trends over time and calculate percentage changes at each extended interval. We hypothesize that there will be no significant difference in NGAL concentrations measured with freshly opened reagents compared to those measured at extended time points. Results Our preliminary results show a slight overall decrease but within imprecision of the assay for both patient samples and controls tested on day 28. We anticipate observing a similar trend on the other timelines upon completion of the analysis. Conclusion The ability to continue using the NGAL reagent beyond its labelled expiration will be an important cost control measure and ensuring continued effective care for our pediatric population.