Elevated Thyroid Peroxidase Antibodies with Encephalopathy in MELAS Syndrome

• Published in: Pediatric neurology 2007-06, Vol.36 (6), p.414-417
• Main Authors: Chan, Derrick W.S., BMBS, Lim, C.C. Tchoyoson, MBBS, Tay, Stacey K.H., MBBS, Choong, Chew-Thye, MBBS, Phuah, Huan Kee, MBBS
• Format: Article
• Language: English
• Subjects: Acidosis, Lactic - etiology; Autoantibodies - blood; Biological and medical sciences; Brain - pathology; Child; Diffusion Magnetic Resonance Imaging; Diseases of striated muscles. Neuromuscular diseases; Female; Hashimoto Disease - complications; Hashimoto Disease - immunology; Humans; Iodide Peroxidase - immunology; Magnetic Resonance Spectroscopy; Malformations of the nervous system; Medical sciences; MELAS Syndrome - complications; Neurology; Pediatrics; Stroke - etiology
• ISSN: 0887-8994; 1873-5150
• DOI: 10.1016/j.pediatrneurol.2007.02.005

Both the syndrome of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS syndrome) and Hashimoto’s encephalopathy can present with nonspecific encephalopathy. Hashimoto’s encephalopathy is an association of steroid-responsive encephalopathy with elevated thyroid peroxidase antibodies. Steroid-responsive encephalopathy, however, is not characteristic of the MELAS syndrome, which typically presents with stroke-like episodes and lactic acidosis in cerebrospinal fluid and blood. Here, a patient is described with goiter, recurrent encephalopathy and elevated thyroid peroxidase antibodies who apparently responded to steroid therapy; however, magnetic resonance imaging was atypical for Hashimoto’s encephalopathy, and she was diagnosed with MELAS syndrome. This syndrome can present with apparent steroid-responsive encephalopathy and elevated thyroid peroxidase antibodies, mimicking Hashimoto’s encephalopathy, and should be suspected if lactic acidosis is present and typical features are detected on magnetic resonance imaging.