Paraneoplastic pemphigus in a dog with splenic sarcoma

Area of Science:

• Veterinary Dermatology
• Autoimmune Diseases
• Oncology

Background:

• Paraneoplastic pemphigus (PNP) is a severe autoimmune blistering disease in humans, characterized by skin lesions and underlying malignancy.
• Canine PNP is exceptionally rare, with only one previous case reported in veterinary literature.

Observation:

• A dog presented with widespread erosions affecting haired skin, mucocutaneous junctions, and oral mucosa.
• Histopathology revealed lesions consistent with both pemphigus vulgaris and erythema multiforme.
• Immunoprecipitation identified circulating IgG autoantibodies targeting five distinct antigens, likely epidermal plakins.

Findings:

• The study provides histologic and serologic evidence supporting a diagnosis of PNP in a dog with splenic sarcoma.
• The canine patient's clinical, histopathologic, and immunologic findings closely mirrored those seen in human PNP.
• The splenic neoplasm was identified as a spindle cell sarcoma.

Implications:

• This case represents the second documented instance of canine PNP and the first association with splenic neoplasia.
• Findings expand the understanding of PNP manifestations in veterinary medicine.
• Highlights the importance of considering autoimmune blistering diseases in dogs with concurrent neoplasia.