For further information about myasthenia gravis, please contact the Neurology/Neurosurgery Service, VMTH. The service provides comprehensive diagnostic procedures for the investigation of neuromuscular diseases including electrophysiology and a dedicated neuromuscular diagnostic laboratory.
Toni Beelard (Service coordinator)
530 754 0606
VMTH Hospital Reception
530 752 1393
Acquired myasthenia gravis (MG) is caused by antibody-mediated inactivation of the acetylcholine receptor on the neuromuscular endplate causing focal, regional or generalized muscle weakness. The course of the disease is often prolonged and many animals are euthanized or die from complications of megaesophagus, regurgitation and aspiration pneumonia.
Costs and time commitment for owners are high, even in cases that respond well to medical management, and most animals require elevated feeding and ongoing management of reurgitation and weakness.
Elevated feeding in a “Bailey chair”
Many medical treatments have been reported; however, responses to therapy and outcomes are unpredictable and death often results from aspiration pneumonia. Currently medical management attempts to maintain animals for weeks to months awaiting spontaneous remission of the disease.
Therapeutic apheresis is an extracorporeal procedure that separates blood into its components for removal or specific alteration prior to return to the patient. Therapeutic plasma exchange (TPE) is an apheresis treatment in which plasma (containing pathologic antibodies) is removed and exchanged with donor plasma. TPE is used routinely to treat MG in human patients with severe disease or disease unresponsive to conventional therapy.
Preliminary data for treatment of refractory MG has been encouraging. Three dogs showed significant improvement after 2 treatments. All dogs received a total of 3 treatments within 5 – 7 days. Treated dogs became ambulatory within 3 days of starting TPE treatment with subsequent resolution of regurgitation and megaesophagus.
Cost for a course of TPE (3 treatments) will range from $3-5,000. However costs are comparable to patients undergoing standard medical therapy and management with a more protracted disease course and common complications.
Advantages of successful TPE may include:
More successful treatment of medically refractory cases
More rapid resolution of clinical signs
Lower incidence of complications
We will be happy to review cases and discuss diagnostic and treatment options for potential patients.