Efficacy of urinary [TIMP-2]⋅[IGFBP7], L-FABP, and NGAL levels for predicting community-acquired acute kidney injury in Japanese patients: a single-center, prospective cohort study.

Background: The combination of urinary tissue inhibitor of metalloproteinase 2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) ([TIMP-2]⋅[IGFBP7]) has emerged as a strong predictor of acute kidney injury (AKI), which is associated with poor outcomes. However, most studies have focused on non-Asian populations, and comparisons of [TIMP-2]⋅[IGFBP7] with other AKI biomarkers in Asian populations have not been performed. Furthermore, no study has examined the efficacy of [TIMP-2]⋅[IGFBP7] for predicting community-acquired AKI.

Methods: We prospectively enrolled adult patients at Kochi Medical School Hospital in Kochi, Japan, and performed a receiver-operating characteristic (ROC) curve analysis to assess the ability of [TIMP-2]⋅[IGFBP7], neutrophil gelatinase-associated lipocalin (NGAL), and liver fatty acid-binding protein (L-FABP) measured at the time of admission to predict AKI.

Results: Of the 170 enrolled patients, 40 (23.5%) developed AKI. Risk factors for AKI development were male sex, history of hypertension, low albumin levels, and high [TIMP-2]⋅[IGFBP7] and NGAL levels. The ROC curve analysis showed that the area under the ROC curve (AUC) of [TIMP-2]•[IGFBP7] for predicting AKI was 0.804 (95% confidence interval [CI], 0.728-0.880); however, the AUCs of L-FABP and NGAL were 0.688 (95% CI, 0.594-0.782) and 0.726 (95% CI, 0.639-0.813), respectively.

Conclusion: Urinary [TIMP-2]⋅[IGFBP7] is a good predictor of community-acquired AKI.