Department of Veterinary Medical Sciences, Alma Mater Studiorum-University of Bologna, Ozzano dell'Emilia, Bologna, Italy.
Department of Comparative Biomedicine and Food Science, University of Padova, Legnaro, Padua, Italy.
Vet Res Commun. 2022 Jun;46(2):613-619. doi: 10.1007/s11259-022-09933-4. Epub 2022 May 5.
The limping syndrome is occasionally reported during acute feline calicivirus (FCV) infections or as consequence of vaccination. In this retrospective study, three clinical cases of lameness in household cats naturally infected by FCV were described and phylogeny of the virus were investigated by analysing the hypervariable E region of the ORF2 viral gene. Cats were diagnosed with polyarthritis and FCV RNA or antigens were detected in symptomatic joints. One cat, euthanized for ethical reasons, underwent a complete post-mortem examination and was subjected to histopathological and immunohistochemical investigations. No phylogenetic subgrouping were evident for the sequenced FCV. Histopathology of the euthanized cat revealed diffuse fibrinous synovitis and osteoarthritis eight months after the onset of lameness and the first detection of FCV RNA, supporting the hypothesis of a persistent infection. FCV was demonstrated by immunohistochemistry in synoviocytes and fibroblasts of the synovial membranes. This study provides new data on the occurrence of polyarthritis in FCV-infected cats, demonstrates by immunohistochemistry the presence of FCV in the synovial membranes of a cat with persistent polyarthritis and supports the absence of correlation between limping syndrome and phylogenetic subgrouping of viruses.
跛行综合征偶尔在猫急性传染性杯状病毒（FCV）感染或疫苗接种后出现。在这项回顾性研究中，描述了 3 例在家养猫中自然感染 FCV 后出现跛行的临床病例，并通过分析 ORF2 病毒基因的高变区 E 区来研究病毒的系统发育。猫被诊断为多发性关节炎，在有症状的关节中检测到 FCV RNA 或抗原。由于伦理原因对一只猫实施了安乐死，对其进行了全面的尸检，并进行了组织病理学和免疫组织化学检查。对测序的 FCV 没有明显的系统发育亚群。在跛行和首次检测到 FCV RNA 8 个月后，安乐死的猫的组织病理学显示弥漫性纤维性滑膜炎和骨关节炎，支持持续性感染的假说。免疫组织化学显示 FCV 存在于滑膜细胞和滑膜纤维母细胞中。本研究提供了 FCV 感染猫发生多发性关节炎的新数据，通过免疫组织化学证明了持续性多发性关节炎猫的滑膜中有 FCV 存在，并支持跛行综合征与病毒的系统发育亚群之间不存在相关性。
