一只8个月大的完好无损的雄性家猫从帕尔马市的多猫收容所转交给帕尔马大学(意大利)兽医科学系兽医教学医院(VTH)的急诊服务,在冬季(2023年1月),为了嗜睡,厌食症,体温过低,和低血糖。在VTH,在心脏检查后,心率的增加,在正常血压条件下,被检测到。信号,临床病史,基础代谢面板(BMP),超声检查,细胞学检查结果均与猫感染性腹膜炎(FIP)的诊断一致.通过分子遗传测试(猫冠状病毒RNA的实时PCR)在腹腔积液中确认了FIP。分子遗传学研究还检测到FCoVS基因单核苷酸突变:生物型M1058L。尸检时,腹部记录了一个渗出的集合,胸腔,和心包囊.白色实质结节,直径约1毫米,被发现在肺的表面和深处,肝脏,肾脏,和心脏。组织病理学显示典型的FIP脓性肉芽肿性血管炎,IHC证实存在FIP病毒(FIPV)抗原。最相关的组织病理学发现是与S基因突变的FCoV(M1058L生物型)的存在相关的心肌炎/心肌坏死。这是FCoV/FIPM1058L生物型阳性的猫中的第一例心肌炎。需要进一步的研究来支持突变的FCoVM1058L生物型,作为一种罕见的,但有可能,FCoV/FIP阳性猫心肌炎的病原体。包括几个FCoV/FIPM1058L阳性病例的研究可以使我们与心脏大体病理相关,组织病理学,和FCoV/FIPM1058L生物型在心肌中的免疫定位。这项研究可能使我们能够确定FCoV/FIPM1058L生物型对心肌细胞的有效取向,或者在存在与患者相关的伴随原因的情况下,心肌细胞病变是否明显。其恶劣的条件,或外部环境困扰,如寒冷季节,以及上述伴随事件是否相关。
An 8-month-old intact male domestic shorthair cat was referred to the Emergency Service of the Veterinary Teaching Hospital (VTH) of the Department of Veterinary Science of the University of Parma (Italy) from the Parma municipal multi-cat shelter, during the winter season (January 2023), for lethargy, anorexia, hypothermia, and hypoglycemia. At the VTH, upon cardiologic examination, an increase in heart rate, under normal blood pressure conditions, was detected. Signalment, clinical history, basal metabolic panel (BMP), ultrasound investigations, and cytological findings were all consistent with a diagnosis of feline infectious peritonitis (FIP).
FIP was confirmed in the effusive abdominal fluid by a molecular genetic test (real-time PCR for feline coronavirus RNA). The molecular genetic investigation also detected an FCoV S gene single-nucleotide mutation: biotype M1058L. At necropsy, an effusive collection was recorded in the abdomen, thoracic cavity, and pericardium sac. White parenchymal nodules, of about 1 mm diameter, were found on the surface and deep in the lungs, liver, kidneys, and heart. Histopathology revealed the typical
FIP pyogranulomatous vasculitis and IHC confirmed the presence of the
FIP virus (FIPV) antigen. The most relevant histopathological finding was the myocarditis/myocardial necrosis associated with the presence of the S gene-mutated FCoV (M1058L biotype). This is the first case of myocarditis in a cat positive for the FCoV/
FIP M1058L biotype. Further studies are necessary to support the mutated FCoV M1058L biotype, as an uncommon, but possible, causative pathogen of myocarditis in FCoV/FIP-positive cats. Studies including several FCoV/FIP M1058L-positive cases could allow us to make a correlation with heart gross pathology, histopathology, and immunolocalization of the FCoV/FIP M1058L biotype in the myocardium. The investigation will potentially allow us to determine the effective tropism of the FCoV/
FIP M1058L biotype for myocardiocytes or whether myocardiocyte lesions are evident in the presence of concomitant causes related to the patient, its poor condition, or external environmental distress such as cold season, and whether the aforementioned concomitant events are correlated.