Mattei Chiara, Pelander Lena, Hansson Kerstin, Uhlhorn Margareta, Olsson Ulf, Häggström Jens, Ljungvall Ingrid, Ley Charles J
University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Vet Radiol Ultrasound. 2019 Jul;60(4):432-446. doi: 10.1111/vru.12755. Epub 2019 May 3.
Ultrasound provides information on kidney morphology, but studies relating structural and functional abnormalities in chronic kidney disease (CKD) are lacking. The aim of this descriptive cross-sectional study was to compare individual kidney (IK) B-mode ultrasound abnormalities to IK glomerular filtration rate (GFR) estimated by scintigraphy normalized to plasma volume (PV) in dogs, to evaluate if ultrasonographic findings were associated with low IKGFR/PV. Eighty privately owned dogs with and without clinical suspicion of CKD were prospectively enrolled, and kidney ultrasound and IKGFR/PV were evaluated independently. Ultrasound images were assessed retrospectively for subjective abnormalities (shape, cortical, and medullary hyperechogenicity), and kidney size was measured. The normal IKGFR/PV cutoff was derived from dogs in the study group with no history and clinical signs of kidney disease and normal blood and urine results (n = 28) and was 16.84 mL/min/L. Kidneys were categorized into normal, mild, moderate, and severe ultrasound changes according to subjective ultrasound grades. Associations were found between low IKGFR/PV and abnormal kidney shape (P = .0004), cortical hyperechogenicity (P = .0008), medullary hyperechogenicity (P < .0001), and low kidney volume (P = .0092). Apart from the moderate and severe category comparison, IKGFR/PV value significantly decreased with increasing severity of category. The combination of ultrasonographic subjective abnormalities had a high sensitivity (93.8%) and moderate specificity (65.7%) for detecting low IKGFR/PV. Kidneys with normal IKGFR/PV had a low frequency of mild ultrasound changes. Findings indicate kidneys with increasing number and grade of subjective ultrasound abnormalities are more likely to have a lower IKGFR/PV.
超声可提供肾脏形态学信息，但关于慢性肾脏病（CKD）结构与功能异常关系的研究尚缺。本描述性横断面研究旨在比较犬个体肾脏（IK）的B型超声异常与通过闪烁扫描法估算并经血浆容量（PV）标准化的IK肾小球滤过率（GFR），以评估超声检查结果是否与低IKGFR/PV相关。前瞻性纳入80只有无CKD临床疑似的私人饲养犬，独立评估肾脏超声和IKGFR/PV。回顾性评估超声图像的主观异常（形状、皮质和髓质回声增强），并测量肾脏大小。正常IKGFR/PV临界值源自研究组中无肾脏疾病病史和临床体征且血液及尿液检查结果正常的犬（n = 28），为16.84 mL/min/L。根据主观超声分级，将肾脏分为正常、轻度、中度和重度超声改变。发现低IKGFR/PV与肾脏形状异常（P = .0004）、皮质回声增强（P = .0008）、髓质回声增强（P < .0001）及肾脏体积减小（P = .0092）相关。除中度和重度类别比较外，IKGFR/PV值随类别严重程度增加而显著降低。超声主观异常的组合对检测低IKGFR/PV具有高敏感性（93.8%）和中度特异性（65.7%）。IKGFR/PV正常的肾脏轻度超声改变频率较低。研究结果表明，主观超声异常数量和分级增加的肾脏更可能具有较低的IKGFR/PV。
