Putative paraneoplastic pemphigus and myasthenia gravis in a cat with a lymphocytic thymoma. Issue 6 (28th October 2013)

• Record Type: Journal Article
• Authors: Hill, Peter B.; Brain, Phil; Collins, David; Fearnside, Steve; Olivry, Thierry
• Is Part Of: Veterinary dermatology. Volume 24:Issue 6(2013:Dec.)
• Page Start: 646
• Page End: e164
• Publication Date: 2013-10-28
• Subjects: Veterinary dermatology -- Periodicals; Pet medicine -- Periodicals; 636.08965
• DOI: 10.1111/vde.12086
• Languages: English
• ISSNs: 0959-4493

Abstract

<abstract abstract-type="main" id="vde12086-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="vde12086-sec-0001" sec-type="section"> <title>Background</title> <p>Paraneoplastic pemphigus (PNP) is a rare and severe autoimmune blistering skin disease of humans. It is associated mainly with haematopoietic neoplasia and a unique autoantibody profile. At this time and in animals, PNP has only been reported in dogs.</p> </sec> <sec id="vde12086-sec-0002" sec-type="section"> <title>Objectives</title> <p>To report clinical, histological and immunological findings in a cat with suspected thymoma‐associated PNP.</p> </sec> <sec id="vde12086-sec-0003" sec-type="section"> <title>Animal</title> <p>An 8‐year‐old female spayed Himalayan cat.</p> </sec> <sec id="vde12086-sec-0004" sec-type="section"> <title>Results</title> <p>The cat presented with a thoracic mass diagnosed as a lymphocytic thymoma. Two weeks postremoval, the cat developed myasthenia gravis, which was controlled with prednisolone and pyridostigmine. The myasthenia gravis resolved, but the cat developed severe cutaneous erosions and ulcers primarily affecting the caudal ventral abdomen and perineum, but also the ventral chest, axillae and medial pinnae. Histopathological analysis revealed changes consistent with pemphigus vulgaris and erythema multiforme, a combination of lesions highly suggestive of PNP. Direct immunofluorescence revealed intercellular epidermal IgG deposition in the lower epidermis, especially in areas of suprabasal clefts. Indirect immunofluorescence revealed antikeratinocyte IgG to basal keratinocytes and bladder epithelial cells. Immunological results supported a diagnosis of PNP. Skin lesions were treated with prednisolone and chlorambucil and, after clinical remission was obtained, the drugs were tapered and eventually discontinued without further recurrence of skin lesions.</p> </sec> <sec id="vde12086-sec-0005" sec-type="section"> <title>Conclusions and clinical importance</title> <p>In this cat, clinical, microscopic and immunological findings were consistent with a diagnosis of PNP, with thymoma being the suspected cause.</p> </sec> </abstract>