[Continuous contrast-enhanced ultrasound applied to acute kidney injury caused by sepsis: a diagnostic clinical study].

OBJECTIVE

To evaluate the diagnostic value of contrast-enhanced ultrasound in acute kidney injury (AKI) caused by sepsis.

METHODS

The sepsis patients admitted to intensive care unit of Tianjin Third Central Hospital from January 2015 to June 2017 were enrolled. All of the patients were completed the 6-hour Bundle treatment and the bilateral renal contrast-enhanced ultrasound within 24 hours, and the peak signal intensity (PSI), peak intensity time (PIT), wash internal rate (WIR) and renal function parameters were measured at the same time. The patients were divided into AKI 24 hours group and non-AKI 24 hours group according to Kidney Disease: Improving Global Outcomes (KDIGO)-AKI diagnostic criteria, and the parameters differences were compared between the two groups. The receiver operating characteristic (ROC) curve were used to analyze the diagnostic value of the parameters. Renal function of the non-AKI group patients was measured again 7 days after hospital admission, and patients were divided into AKI 7 days group and non-AKI 7 days group, and the related parameters of the two groups measured within 24 hours were compared.

RESULTS

(1) Ninety-six patients were enrolled, with 39 cases of AKI occurred within 24 hours after admission, and with an incidence of 40.6%. Contrast-enhanced ultrasound showed that the time-intensity curve (TIC) of non-AKI patients manifested as a slow down after rapid rise to the peak, but the AKI patients showed as slow rise to the peak and more slow decrease. Compared with non-AKI 24 hours group, AKI 24 hours group performance as PSI weakened, PIT extended and WIR decreased [PSI (dB): 114.41±19.38 vs. 141.24±24.65, PIT (s): 22.86±4.29 vs. 17.39±3.68, WIR (dB/s): 5.53±4.17 vs. 7.85±1.84, all P < 0.01]. ROC curve analysis showed that area under the ROC curve (AUC) of WIR, PIT, PSI was 0.85, 0.84, 0.82 respectively (all P < 0.01), the cut-off value of WIR was 7.18 dB/S, the sensitivity, specificity and accuracy were 82.05%, 80.70% and 81.25% respectively; the cut-off value of PIT was 18.45 s, the sensitivity, specificity and accuracy were 74.35%, 73.68% and 73.95% respectively; the cut-off values of PSI was 121.21 dB, the sensitivity, specificity and accuracy were 71.79%, 87.72% and 81.25% respectively. (2) The incidence of AKI within 7 days in non-AKI patients was 26.3% (15/57). There were significant differences in PIT, WIR and PSI between AKI 7 days group and non-AKI 7 days group [PSI (dB): 124.97±26.64 vs. 147.02±21.51, PIT (s): 20.61±3.27 vs. 16.24±3.13, WIR (dB/s): 6.81±1.76 vs. 8.22±1.75, all P < 0.05]. However, there was no significant difference in serum creatinine (SCr), blood urea nitrogen (BUN) and creatinine clearance rate (CCr).

CONCLUSIONS

Compared to SCr and BUN, contrast-enhanced ultrasound parameters can early response to renal dysfunction, and contribute to early diagnosis of sepsis induced AKI.