Preoperative and intraoperative ultrasound aids removal of migrating plant material causing iliopsoas myositis via ventral midline laparotomy: a study of 22 dogs.

BACKGROUND: Migrating plant material is often suspected clinically to be the underlying cause of iliopsoas myositis in the dog, but cannot always be found pre- or intraoperatively. In most cases, recurrence of clinical signs is related to failure to remove the plant material. Preoperative ultrasonography can be useful to visualize migrating plant material and to determine anatomical landmarks that can assist in planning a surgical approach. The purpose of the present study was to report the role of intraoperative (intra-abdominal) ultrasonography for visualizing and removing the plant material from iliopsoas abscesses using a ventral midline laparotomy approach. RESULTS: A retrospective case series of 22 dogs with iliopsoas muscle abnormalities and suspected plant material was reported. Preoperative visualization and subsequent retrieval of the plant material was performed during a single hospitalization. In all 22 dogs, the plant material (including complete grass awns, grass awn fragments and a bramble twig) was successfully removed via ventral midline laparotomy in which intraoperative ultrasonography was used to direct the grasping forceps tips to the foreign body and guide its removal. In 11 of these 22 dogs, the plant material was not completely removed during prior surgery performed by the referring veterinarians without pre- or intraoperative ultrasonography. Clinical signs resolved in all dogs and all dogs resumed normal activity after successful surgical removal of the plant material. CONCLUSION: Intraoperative ultrasonography is a safe and readily available tool that improves success of surgical removal of plant material within the iliopsoas abscesses via ventral midline laparotomy. Moreover, ultrasonographic findings of unusual plant material can be useful in planning and guiding surgical removal, by providing information about the size and shape of the foreign body.

Myopathy in a rhesus monkey with biopsy findings similar to human sporadic inclusion body myositis.

A rhesus macaque with generalized muscle atrophy and musculotendinous contractures was detected in our research center. Muscle biopsies showed myofibers with rimmed vacuoles and eosinophilic hyaline inclusions, accumulations of CD8+ and CD4+ lymphocytes and expression of major histocompatibility complex class I in myofibers. Intracellular inclusions were positive to Congo red. Semithin sections and transmission electron microscopy showed autophagic vacuoles within myofibers and myonuclei with inclusions of filaments. These morphological observations conform with the diagnostic criteria of human sporadic inclusion body myositis. This is the first report of this myopathy in nonhuman primates.

Vacuolar myopathy in a dog resembling human sporadic inclusion body myositis.

Sporadic inclusion body myositis (sIBM) is the most common myopathy in people over the age of 50 years. While immune-mediated inflammatory myopathies are well documented in dogs, sIBM has not been described. An 11-year-old dog with chronic and progressive neuromuscular dysfunction was evaluated for evidence of sIBM using current pathologic, immunohistochemical and electron microscopic diagnostic criteria. Vacuoles and congophilic intracellular inclusions were identified in cryostat sections of multiple muscle biopsies and immunostained with antibodies against amyloid-beta peptide, amyloid-beta precursor protein, and proteosome 20S of the ubiquitin-proteosome system. Cellular infiltration and increased expression of MHC Class I antigen were observed. Cytoplasmic filamentous inclusions, membranous structures, and myeloid bodies were identified ultrastructurally. These observations constitute the first evidence that both the inflammatory and degenerative features of human sIBM can occur in a non-human species.

Inclusion body myositis in spring peepers (Pseudacris crucifer).

In 2000, 2 adult captive spring peepers (Pseudacris crucifer) from the same zoological park were humanely euthanized. Histologically, both frogs had degeneration, atrophy, and necrosis of striated myofibers of the tongue admixed with chronic lymphohistiocytic inflammation. One frog had similar lesions in the skeletal muscles of the body wall. Several degenerate and necrotic myofibers contained single, eosinophilic, intranuclear inclusion bodies. Ultrastructural examination of the inclusions revealed nonenveloped, icosahedral, virus-like particles averaging 20-24 nm in diameter. This is the first reported case of inclusion body myositis in frogs and is believed to be due to parvoviral infection.