Abstract: SA-OR042

Using KDIGO Criteria, Beta-2 Microglobulin Predicts the Development of AKI

Session Information

Category: Developmental Biology and Inherited Kidney Diseases

  • 403 Pediatric Nephrology

Authors

  • Barton, Kevin T, Washington University School of Medicine, St Louis, Missouri, United States
  • Gu, Hongjie, Washington University School of Medicine, St Louis, Missouri, United States
  • Goss, Charles, Washington University School of Medicine, St Louis, Missouri, United States
  • Dietzen, Dennis, Washington University School of Medicine, St Louis, Missouri, United States
  • Kakajiwala, Aadil K., Washington University School of Medicine, St Louis, Missouri, United States
  • Dharnidharka, Vikas R., Washington University School of Medicine, St Louis, Missouri, United States
Background

Beta-2-microglobulin (B2M) is a functional marker of proximal tubular injury and glomerular filtration. Analyses using older/non-standardized definitions have shown low efficacy of B2M as a predictor of AKI. We assessed if elevated levels of B2M would predict the diagnosis of or recovery from AKI.

Methods

We performed a retrospective study including children >1 year, between 01/2011 and 12/2015, who had urine (UB2M) and/or serum B2M (SB2M) measured by immunoturbidometry. We defined AKI using changes in serum creatinine (sCr) based on KDIGO criteria and urine output <0.5 mL/kg/hr for 24 hours. We defined recovery from AKI as return to baseline serum creatinine within six months of AKI. We gathered data on baseline, maximum and recovery sCr, SB2M, and UB2M. We calculated receiver-operating-characteristic (ROC) area under curves (AUC).

Results

245/529 patients developed AKI. SB2M and UB2M predicted AKI development with an ROC-AUC of 0.84 and 0.73 respectively (Figure 1). Patients had a graded higher median SB2M and UB2M with each higher AKI Stage. SB2M and UB2M differentiated between Stage I and Stage III AKI (both p-value <0.0001). Serum B2M also differentiated between Stage II and Stage III AKI (p-value <0.0001). However, neither UB2M nor SB2M levels predicted recovery from AKI. Only older age and need for dialysis predicted less than complete recovery after AKI (HR: 0.97 (CI 0.94, 0.99) and 0.39 (CI 0.23, 0.61) respectively).

Conclusion

Using the latest AKI definition, serum B2M performs well to predict AKI. Given the relative ease and lower cost of B2M we suggest more widespread use of B2M for the detection of AKI.

VariableAKI (Median [IQR])No AKI (Median [IQR])p-value
Serum B2M (mg/L)4.3 (2.8,9.6)1.7 (1.3,2.5)< 0.0001
Urine B2M (mg/L)3.2 (0.4, 16.8)0.2 (0.2, 0.9)< 0.0001