Reynolds Rachel M, Marks Stanley L, Guo Ling T, Shelton G Diane, Graham Karina J
Veterinary Specialists of Sydney, Miranda, NSW, Australia.
School of Veterinary Medicine, University of California, Davis, CA, USA.
JFMS Open Rep. 2024 Aug 2;10(2):20551169241254227. doi: 10.1177/20551169241254227. eCollection 2024 Jul-Dec.
A 6-month-old male entire domestic shorthair cat presented for presumptive myopathy that was non-responsive to antiprotozoal therapy. Clinical features included marked macroglossia, dysphagia, regurgitation, truncal muscle hypertrophy, pelvic limb gait abnormalities and megaoesophagus. Relevant diagnostics included serial creatine kinase activity, cardiac troponin I, fluoroscopic swallow study and routine muscle histopathology. Ultimately, post-mortem histopathology with immunostaining demonstrated markedly decreased or absent staining for the rod and carboxy terminus of dystrophin, confirming a dystrophin-deficient muscular dystrophy (MD). The misdiagnosis of toxoplasmosis was based on an increased IgG titre and muscle histopathology submitted to a local laboratory. Treatment for megaoesophagus included vertical feeding of wet food only, sildenafil and omeprazole. Dysphagia and regurgitation improved moderately. Presumptive hyperaesthesia and muscle pain were managed with anti-inflammatory doses of prednisolone. The patient was ultimately euthanased as a result of progressive MD signs and uraemia at 2 years of age.
This case report highlights the collective clinical features of MD, as they could be considered pathognomonic for this rare condition and must be differentiated from other myopathies via specific immunostaining of muscle biopsies. This is crucial to obtain a correct and early diagnosis, allowing instigation of potentially valuable treatments. Megaoesophagus is an inconsistent feature in feline MD in addition to the more commonly observed oropharyngeal dysphagia. Management with a canned diet, sildenafil, omeprazole and upright feeding was beneficial with moderate improvement in the frequency of regurgitation. Prednisolone was thought to minimise the presumptive myalgia.
一只6个月大的雄性未绝育家养短毛猫因疑似肌病就诊，对抗原虫治疗无反应。临床特征包括明显的巨舌症、吞咽困难、反流、躯干肌肉肥大、后肢步态异常和巨食管症。相关诊断包括连续检测肌酸激酶活性、心肌肌钙蛋白I、荧光吞咽研究和常规肌肉组织病理学检查。最终，死后组织病理学检查及免疫染色显示肌营养不良蛋白的杆状和羧基末端染色明显减少或缺失，确诊为肌营养不良蛋白缺乏性肌营养不良（MD）。将其误诊为弓形虫病是基于当地实验室检测的IgG滴度升高和肌肉组织病理学检查结果。巨食管症的治疗包括仅垂直喂食湿粮、西地那非和奥美拉唑。吞咽困难和反流症状有一定程度改善。推测的感觉过敏和肌肉疼痛通过给予抗炎剂量的泼尼松龙进行处理。该患者最终因进行性MD体征和尿毒症于2岁时实施安乐死。
本病例报告突出了MD的综合临床特征，这些特征可被视为这种罕见疾病的特征性表现，必须通过肌肉活检的特异性免疫染色与其他肌病相鉴别。这对于获得正确的早期诊断至关重要，从而能够启动可能有价值的治疗。除了更常见的口咽吞咽困难外，巨食管症是猫MD中一个不一致的特征。采用罐装饮食、西地那非、奥美拉唑和垂直喂食进行管理是有益的，反流频率有一定程度的改善。泼尼松龙被认为可将推测的肌痛降至最低。
