Mucopolysaccharidosis (Cats)

Myositis is inflammation of muscle tissue that results in pain, weakness, and muscle atrophy (shrinking). Myositis can be caused by a number of different disease entities, including toxoplasmosis, leptospirosis, bacterial infections (abscesses), low blood potassium (see text below), and autoimmune disease. One special type of myositis, called masticatory myositis, affects the facial muscles of affected dogs, causing atrophy and the inability to chew normally.

Myositis isdiagnosed using clinical signs and blood tests designed to detect increased  levels in muscle enzymes within the blood. In especially elusive cases, biopsy samples taken from suspected muscle tissue can help veterinarians obtain a definitive diagnosis.

Treatment: appropriate antimicrobial or antiparasitic therapy will help relieve the myositis. Anti-inflammatory medications can also be used to relieve the pain and discomfort associated with the inflammation until the underlying cause is treated.

The term myopathy refers to abnormal anatomy and/or function of skeletal muscle tissue within the body. Chow chows, golden retrievers, and Irish terriers are examples of breeds that can suffer from inherited myopathies. Dogs suffering from myopathies exhibit abnormal postures, stiff gaits, and generalized shrinking or atrophy of the muscles. Because of the inherited nature of these diseases, the onset of clinical signs usually occurs within a year of age.