Huvé Romain, Fontaine Pascal, Blais Marie-Claude, Conversy Bérénice
Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Montréal, Saint-Hyacinthe, QC, Canada.
JFMS Open Rep. 2020 Dec 21;6(2):2055116920979271. doi: 10.1177/2055116920979271. eCollection 2020 Jul-Dec.
An 8-month-old neutered male domestic shorthair kitten was examined for anorexia, lethargy and palatine ulcers. Systemic lupus erythematosus (SLE) was suspected based on a positive antinuclear antibody (ANA) titer and six manifestations of autoimmunity: fever, paronychia, oral ulcers, proteinuria, thrombocytopenia and leukopenia. Mastocytemia was observed on the blood smear. Although the clinical presentation of this case meets the classification criteria for SLE in humans, tick-borne disease and histopathology evaluation of the oral and cutaneous lesions would have been necessary to support a definite diagnosis of SLE. Baseline ANA titration was performed in two laboratories with conflicting results, which may reflect substrate differences used for the titration, but a false-positive result cannot be excluded. The cat received prednisolone and all clinical and laboratory abnormalities resolved after two months of treatment. Subsequent ANA titers remained positive and were not correlated to the patient's clinical progression.
This report describes new findings associated with a presumptive diagnosis of SLE in a kitten, highlighting that SLE may not be ruled out even in young cats and may be associated with mastocytemia. ANA titration is part of the initial diagnostic work-up of SLE but is a non-specific test and discrepancies can be observed between laboratories. The titration of more specific antibodies such as those used in humans would be helpful to diagnose SLE. ANA titration may not correlate with clinical activity of SLE; hence, the interest of an ANA titer follow-up to establish disease control warrants further investigation.
一只8个月大已绝育的雄性家养短毛小猫因厌食、嗜睡和腭部溃疡接受检查。基于抗核抗体（ANA）滴度阳性以及自身免疫的六种表现：发热、甲沟炎、口腔溃疡、蛋白尿、血小板减少和白细胞减少，怀疑患有系统性红斑狼疮（SLE）。血液涂片观察到肥大细胞血症。尽管该病例的临床表现符合人类SLE的分类标准，但仍需要进行蜱传疾病以及口腔和皮肤病变的组织病理学评估以支持SLE的确切诊断。在两个实验室进行了基线ANA滴度检测，结果相互矛盾，这可能反映了用于滴定的底物差异，但不能排除假阳性结果。这只猫接受了泼尼松龙治疗，两个月后所有临床和实验室异常均得到缓解。随后的ANA滴度仍为阳性，且与患者的临床进展无关。
本报告描述了与一只小猫SLE疑似诊断相关的新发现，强调即使在幼猫中也不能排除SLE，且可能与肥大细胞血症有关。ANA滴度检测是SLE初始诊断检查的一部分，但它是一项非特异性检测，不同实验室之间可能会出现差异。滴定更特异性的抗体（如人类使用的那些）将有助于诊断SLE。ANA滴度可能与SLE的临床活动无关；因此，通过随访ANA滴度来确定疾病控制情况是否有用值得进一步研究。
