T-lymphocyte-rich thymoma and myasthenia gravis in a Siberian tiger (Panthera tigris altaica).
A 10-year-old captive male Siberian tiger (Panthera tigris altaica) presented with acute onset collapse, vomiting and dyspnoea, preceded by a 6-month period of progressive muscle wasting. Following humane destruction, post-mortem examination revealed a large multilobulated mass in the cranial mediastinum, which was diagnosed as a T-lymphocyte-rich thymoma with the aid of immunohistochemistry. Retrospective serology for acetylcholine receptor antibodies (titre 3.90 nmol/l) confirmed a diagnosis of thymoma-associated myasthenia gravis. Thymomas are reported rarely in wild carnivores, but when detected they appear to be similar in morphology to those seen in domestic carnivores and may also be accompanied by paraneoplastic syndromes. The clinical signs of myasthenia gravis in the tiger were consistent with those reported in cats and dogs and the condition is proposed as an important differential diagnosis for generalized weakness in captive Felidae.
School of Veterinary Medicine, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK. Electronic address: Kathryn.Allan@glasgow.ac.uk.
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K
Allan
Zoological Society of London, Regent's Park, London NW1 4RY, UK.
N
N
Masters
Abbey Veterinary Services, 89 Queen Street, Newton Abbot, Devon TQ12 2BG, UK.
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Rivers
ZSL Whipsnade Zoo, Dunstable, Bedfordshire LU6 2LF, UK.
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K
Berry
Zoological Society of London, Regent's Park, London NW1 4RY, UK.
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A
Routh
School of Veterinary Medicine, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK.
C
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Lamm
D000818:Animals; D008297:Male; D009157:Myasthenia Gravis / Q000473:pathology / Q000662:veterinary*; D013601:T-Lymphocytes / Q000473:pathology*; D013945:Thymoma / Q000473:pathology / Q000662:veterinary*; D013953:Thymus Neoplasms / Q000473:pathology / Q000662:veterinary*; D046010:Tigers
Panthera tigris altaica; Siberian tiger; myasthenia gravis; thymoma