MR扩散张量成像评估高尿酸血症患者肾损伤

目的 探讨MR扩散张量成像评价高尿酸血症早期肾功能损伤的可行性。方法 收集23例男性无症状高尿酸血症（AH组）、30例痛风（GA组）患者及23名健康志愿者（HC组）。检测血清尿酸浓度（SUA），估算肾小球滤过率（eGFR）。行常规MRI及DTI，比较3组间肾皮、髓质表观扩散系数（ADC）值及各向异性（FA）值、SUA、eGFR差异，并分别分析其与SUA及eGFR的相关性；同时分析SUA与eGFR间的关系。结果 HC组SUA值低于AH组及GA组（P均<0.05），GA组eGFR低于HC组（P<0.05）。AH组与GA组肾皮质和髓质的FA值均低于HC组（P均<0.05）；AH组、GA组肾皮质ADC值和GA组肾髓质ADC值均低于HC组（P均<0.05）。肾皮、髓质FA值（r=-0.41、-0.40）及肾皮、髓质ADC值（r=-0.34、-0.28）与SUA均呈负相关（P均<0.05），而肾皮、髓质DTI各参数与eGFR无明显相关性；SUA与eGFR呈负相关（r=-0.43，P<0.05）。结论 DTI可用于评估高尿酸血症早期肾功能损伤；高尿酸血症肾皮质ADC值及肾皮、髓质FA值均低于正常人；肾皮、髓质ADC值及FA值与SUA均呈负相关，SUA与肾功能损伤程度呈正相关。

Assessing kidney injury of hyperuricemia patients with MR diffusion tensor imaging

Objective To investigate the feasibility of MR diffusion tensor imaging (DTI) in evaluating early renal function injury of hyperuricemia. Methods Totally 23 male patients with asymptomatic hyperuricemia (AH group), 30 patients with gouty arthritis (GA group) and 23 healthy volunteers (HC group) were collected. Serum uric acid (SUA) and estimated glomerular filtration rate (eGFR) were recorded, and then routine MRI and DTI were performed. The differences of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values of renal cortex or medulla, SUA and eGFR of 3 groups were compared. The correlations of ADC and FA values of renal cortex or medulla with SUA and eGFR were analyzed, and the correlation of SUA and eGFR was analyzed. Results SUA of HC group was lower than that of AH and GA group (both P<0.05), while eGFR of GA group was lower than that of HC group (P<0.05). FA values of renal cortex and medulla in AH group and GA group were lower than that of HC group (all P<0.05). The cortical ADC values in AH group and GA group and medullary ADC value in GA group were lower than that in HC group (all P<0.05). FA values of renal cortex and medulla (r=-0.41, -0.40), ADC values of renal cortex and medulla (r=-0.34, -0.28,) showed negative correlations with SUA (all P<0.05) but not with eGFR. Also, negative correlation of eGFR and SUA was found (r=-0.43, P<0.05). Conclusion DTI can be used to evaluate early renal function injury caused by hyperuricemia. ADC and FA value of renal cortex and medulla of hyperuricemia patients are lower than that of normal people. ADC value and FA value of renal cortex or medulla are negatively correlated with SUA, while SUA is positively correlated with the degree of renal impairment.