[Value of renal injury marker protein in early diagnosis of acute kidney injury in burn delayed resuscitation patients].

Abstract

Objective: To explore the value of renal injury marker protein in early diagnosis of acute kidney injury (AKI) in burn delayed resuscitation patients. Methods: Retrospective clinical research was conducted. Forty-three burn delayed resuscitation patients [27 males and 16 females, with age of 75 (35±3) years] were admitted to Zhengzhou First People s Hospital from May 2018 to May 2020 and met the inclusion criteria. The patients were divided into AKI group of 23 patients and non-AKI group of 20 patients according to whether acute kidney injury (AKI) occurred within 7 days after burns. The gender, age, deep partial-thickness burn area, full-thickness burn area, acute physiology and chronic health score Ⅱ, and fluid supplement volume at 12, 24, and 48 h after burn were compared between the two groups. Serum creatinine and albumin/fibrinogen ratio (AFR) at 12, 24, 48, 72, 120, 168 h after burn were detected. Urinary heat shock protein 70 (HSP-70), tissue inhibitor of metalloproteinase-2 (TIMP-2), and insulin-like growth factor binding protein 7 (IGFBP-7) were measured by enzyme-linked immunosorbent assay at 12, 24, 48, 72, 120, 168 h after burn, and the TIMP-2×IGFBP-7 was calculated. Urinary neutrophil gelatinase associated lipocalin (NGAL) was measured by immunoturbidimetry at the above 6 time points. Data were statistically analyzed with Mann-Whitney U test, analysis of variance for repeated measurement, and t test. The independent variable to predict the occurrence of AKI was screened by logistic regression analysis. The receiver operating characteristic curve was drawn, and the area under the curve (AUC), the best threshold, and the sensitivity and specificity under the best threshold were calculated. Results: The gender, age, deep partial-thickness burn area, full-thickness burn area, acute physiology and chronic health score Ⅱ of patients in the two groups were similar (t=1.98, 1.98, 1.99, 1.99, 1.99, P>0.05). The fluid supplement volume of patients in AKI group at 12, 24, and 48 h after burn was significantly less than that in non-AKI group (t=15.37, 6.51, P<0.01). The serum creatinine of patients in AKI group at 12, 24, and 48 h after burn was significantly higher than that in non-AKI group (Z=2.16, 5.62, 6.72, P<0.01). The serum AFR of patients in AKI group at 12, 24, 48, 72, 120, 168 h after burn was significantly lower than that in non-AKI group (t=16.14, 35.35, 19.60, 20.47, 30.20, 21.17, P<0.01). The levels of urinary HSP-70 of patients in AKI group at 12, 24, 48, 72, 120, 168 h after burn were (6.89±0.87), (6.42±0.73), (5.81±0.72), (5.17±0.56), (4.63±0.51), (3.89±0.51) μg/L, which were significantly higher than (3.89±0.75), (3.57±0.63), (2.66±0.41), (1.83±0.35), (1.48±0.19), (1.28±0.19) μg/L in non-AKI group (t=12.00, 13.61, 17.39, 22.98, 26.34, 21.59, P<0.01). Urinary TIMP-2×IGFBP-7 and NGAL of patients in AKI group at 12, 24, 48, 72, 120, 168 h after burn were significantly higher than those in non-AKI group (t=26.94, 101.11, 35.50, 66.89, 17.34, 14.30, 14.00, 13.78, 12.32, 14.80, 21.36, 22.62, P<0.01). Urinary HSP-70 peaked at 12 h after burn, TIMP-2×IGFBP-7 and NGAL peaked on 1 d after burn, and serum AFR reached the lowest value at 12 h after AFR, which were included into logistic regression analysis (odds ratio=2.42, 1.52, 5.61, 1.47, 95% confidence interval=1.99-2.95, 2.87-9.68, 2.14-14.69, 1.86-3.92, P<0.01). For 43 patients with burn delayed resuscitation, the AUC of receiver operating characteristic curve of AFR at 12 h after burn for predicting AKI was 0.739, the optimal threshold was 9.90, the sensitivity was 82%, and the specificity was 90%. The AUC of HSP-70 at 12 h after burn was 0.990 at 12 h after burn, the optimal threshold was 1.40 μg/L, the sensitivity was 98%, and the specificity was 96%. The AUC of TIMP-2×IGFBP-7 was 0.715, the optimal threshold was 114.20 μg(2)/L(2), the sensitivity was 91%, and the specificity was 95%. The AUC of NGAL on 1 d after burn was 0.972, the optimal threshold was 78 μg/L, the sensitivity was 95%, the specificity was 96%. Conclusions: HSP-70 and NGAL have high value in early diagnosis of AKI in burn delayed resuscitation patients.