Table 1_Case Report: Budd–Chiari-like syndrome in a cat with polycystic kidney and liver disease.docx

A 9-year-old spayed female Persian Chinchilla cat presented with progressive lethargy and acute right hindlimb pain and lameness. Diagnostic imaging revealed diffuse renal and hepatic cysts, resulting in marked hepatomegaly. Computed tomography (CT) further identified a localized narrowing of the intrahepatic caudal vena cava (CVC), likely due to extrinsic compression by the enlarged liver. Laboratory tests revealed moderate anemia, leukocytosis, hypoalbuminemia, and a hypercoagulable state with markedly elevated serum amyloid A levels. Based on these findings, the cat was diagnosed with polycystic kidney and liver disease (PKD/PLD), complicated by Budd–Chiari-like syndrome (BCLS), a rare hemodynamic disorder in felines. Despite supportive care, the patient succumbed to renal failure within 7 weeks. Whole-genome sequencing identified a heterozygous known pathogenic non-sense mutation in PKD1 (XM_023247051.2:c.9864C > A), a novel frameshift mutation in GANAB, and multiple missense variants in PKD1 and PKHD1. To the best of our knowledge, this is the first reported case of feline BCLS secondary to PLD-induced CVC compression. These findings underscore the importance of considering vascular complications in advanced PKD/PLD and suggest that multigenic variation may contribute to disease severity and clinical variability.

一只9岁已绝育的雌性金吉拉波斯猫（Persian Chinchilla cat）因进行性嗜睡、急性右后肢疼痛及跛行就诊。诊断影像学检查可见弥漫性肾囊肿与肝囊肿，引发显著肝肿大。计算机断层扫描（Computed tomography, CT）进一步检出肝内下腔静脉（intrahepatic caudal vena cava, CVC）局限性狭窄，推测由肿大肝脏的外源性压迫所致。实验室检查显示中度贫血、白细胞增多症、低白蛋白血症，伴高凝状态且血清淀粉样蛋白A（serum amyloid A, SAA）水平显著升高。基于上述结果，该猫被诊断为多囊肝肾疾病（polycystic kidney and liver disease, PKD/PLD），并发类巴德-吉亚利综合征（Budd–Chiari-like syndrome, BCLS）——一种家猫中罕见的血流动力学紊乱性疾病。尽管接受了支持治疗，该患猫仍在7周内死于肾衰竭。全基因组测序（Whole-genome sequencing, WGS）检出PKD1基因存在1处杂合的已知致病性无义突变（XM_023247051.2:c.9864C > A）、GANAB基因存在1处新型移码突变，同时PKD1与PKHD1基因携带多处错义变异。据我们所知，这是首例报道的由多囊肝肾疾病诱发下腔静脉压迫继发的猫类布加样综合征病例。本研究结果凸显了在晚期多囊肝肾疾病中考虑血管并发症的重要性，并提示多基因变异可能参与影响疾病严重程度与临床异质性。