Case report: Successful treatment of intestinal leiomyositis in a dog using adjunctive intravenous immunoglobulin.

A 10-year-old spayed female Dachshund presented with abdominal pain and generalized severe ileus. An exploratory laparotomy was performed, confirming a severe ileus of undetermined origin. Multiple intestinal biopsy results confirmed acute intestinal leiomyositis. Immunohistochemistry (IHC) stains confirmed a T-cell predominant inflammatory infiltrate. Intravenous immunoglobulin (hIVIG) was administered prior to immunosuppressive therapy. Within 10 days of hIVIG treatment, functional peristaltic activity returned, and symptoms resolved. Long-term management, including the use of mycophenolate, resulted in sustained functional peristaltic recovery. Further studies are needed to explore the potential benefits of hIVIG treatment in the stabilization phase of this commonly fatal, treatment-refractory disease.