Wang Xiangyu, Liu Jiajia, Chen Luzeng, Su Tao
Department of Ultrasound Medicine, Peking University First Hospital, Beijing, China.
Department of Medicine, Renal Division, Peking University First Hospital, Beijing, China.
Ren Fail. 2025 Dec;47(1):2542525. doi: 10.1080/0886022X.2025.2542525. Epub 2025 Aug 7.
Acute kidney injury (AKI) progression involves complex microcirculatory and structural changes poorly captured by conventional metrics. This study investigates contrast-enhanced ultrasound (CEUS) and shear wave elastography (SWE) to evaluate hemodynamic redistribution and fibrosis in AKI patients.
Prospective cohort study of 16 biopsy-confirmed tubulointerstitial (TI) nephritis patients and matched controls. We aim to explore the potential correlation of CEUS-SWE derived parameters (peak intensity (PI), rise time (RT), time to peak (TTP), and shear wave velocity (SWV)) with renal histopathology and 3-month outcomes (renal recovery: estimated glomerular filtration rate (eGFR) ≥45 mL/min/1.73 m).
CEUS revealed stage-specific perfusion patterns: milder AKI (eGFR >25 mL/min/1.73 m) showed medullary hyperemia (cortical-to-medullary PI ratio: 0.80 ± 0.24 vs. 1.12 ± 0.18 in controls; < .05), a potential compensatory response to medullary hypoxia. Cortical-to-medullary ratios of PI, RT, and TTP significantly correlated with chronic TI injury ( = 0.501/-0.576/-0.547), reflecting capillary rarefaction's role in disease severity and fibrosis. Patients with severe renal dysfunction (eGFR <25 mL/min/1.73 m) exhibited elevated renal artery resistive indices. In stage 3 AKI, PI ratio demonstrated positive correlation with glomerulosclerosis ( = 0.690, = .03), cortical RT/TTP correlated inversely with chronic TI injury ( = -0.807/-0.821, = .005/.004), reflecting cortical hypoperfusion and impaired compensatory perfusion redistribution during AKI. Prognostically, patients with lower PI ratio (indicating preserved medullary hyperemia) experienced better renal recovery (64.3% achieving eGFR ≥45 mL/min/1.73 m; = .02). SWE-derived SWV declined with AKI severity ( < .05) but lacked fibrosis specificity due to edema/necrosis confounders.
CEUS-derived PI ratios quantify microcirculatory dysfunction in AKI, correlating with chronic TI injury and predicting recovery.
急性肾损伤（AKI）的进展涉及复杂的微循环和结构变化，传统指标难以充分反映这些变化。本研究探讨对比增强超声（CEUS）和剪切波弹性成像（SWE），以评估AKI患者的血流动力学再分布和纤维化情况。
对16例经活检确诊的肾小管间质（TI）肾炎患者及匹配的对照组进行前瞻性队列研究。我们旨在探讨CEUS-SWE得出的参数（峰值强度（PI）、上升时间（RT）、达峰时间（TTP）和剪切波速度（SWV））与肾脏组织病理学及3个月预后（肾脏恢复：估计肾小球滤过率（eGFR）≥45 mL/min/1.73 m²）之间的潜在相关性。
CEUS显示出阶段特异性灌注模式：较轻的AKI（eGFR >25 mL/min/1.73 m²）表现为髓质充血（皮质与髓质PI比值：对照组为1.12±0.18，AKI组为0.80±0.24；P<0.05），这可能是对髓质缺氧的一种代偿反应。PI、RT和TTP的皮质与髓质比值与慢性TI损伤显著相关（r = 0.501/-0.576/-0.547），反映了毛细血管稀疏在疾病严重程度和纤维化中的作用。严重肾功能不全（eGFR <25 mL/min/1.73 m²）的患者肾动脉阻力指数升高。在3期AKI中，PI比值与肾小球硬化呈正相关（r = 0.690，P = 0.03），皮质RT/TTP与慢性TI损伤呈负相关（r = -0.807/-0.821，P = 0.005/0.004），反映了AKI期间皮质灌注不足和代偿性灌注再分布受损。在预后方面，PI比值较低（表明髓质充血得以保留）的患者肾脏恢复情况较好（64.3%的患者eGFR≥45 mL/min/1.73 m²；P = 0.02）。SWE得出的SWV随AKI严重程度下降（P<0.05），但由于水肿/坏死等混杂因素，缺乏纤维化特异性。
CEUS得出的PI比值可量化AKI中的微循环功能障碍，与慢性TI损伤相关并可预测恢复情况。
