Focal form of acquired myasthenia gravis with megaesophagus in a Yorkshire terrier dog

  • Hahn, Tae-Yeon (Department of Veterinary Internal Medicine, College of Veterinary Medicine, Konkuk University) ;
  • Kang, Min-Hee (Department of Veterinary Internal Medicine, College of Veterinary Medicine, Konkuk University) ;
  • Eom, Ki-Dong (Department of Veterinary Radiology, College of Veterinary Medicine, Konkuk University) ;
  • Park, Hee-Myung (Department of Veterinary Internal Medicine, College of Veterinary Medicine, Konkuk University)
  • Received : 2013.02.18
  • Accepted : 2013.07.02
  • Published : 2014.03.31


A 12-year-old, castrated male Yorkshire terrier dog presented with frequent regurgitations that had begun 45 days earlier and become more progressive. Radiographs revealed an air-trap region behind the cranial esophageal sphincter muscle in the esophagus and esophagographies with barium contrast showed mild esophageal dilation with decreased motility. Esophageal motility increased within 5 min of neostigmine methylsulfate administration and acetylcholine receptor antibodies titer increased to beyond the normal range. Based on these findings, acquired myasthenia gravis with focal form was diagnosed, making this the first such case diagnosed by an acetylcholine receptor antibody test in Korea.


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