Skip to main content


What is Myositis?

Inflammatory muscle diseases include and are often called myositis, myopathy, or inflammatory myopathies. Myositis is a type of autoimmune condition characterized by weak, aching, and inflamed muscles. Patients with myositis may fall or trip often. Like with all autoimmune diseases, the body responds as if there is an infection, but ends up attacking its own healthy tissues. The most common types are myositis are polymyositis, dermatomyositis, inclusion body myositis, and necrotizing autoimmune myopathy.


With polymyositis, skeletal muscles responsible for movement slowly weaken because inflamed cells misfire at muscle fibers. This most often impacts muscles in the hips, thighs, and shoulders. Patients are typically adults, more often female, ages 30 to 60. If left untreated, patients may struggle to swallow, speak, stand, or otherwise be active. Other symptoms may include arthritis, shortness of breath, and heart issues.


Dermatomyositis attacks both the muscles and the blood vessels responsible for taking blood to the muscle and skin. This causes a purple or red rash that can develop on the knuckles, elbows, knees, face, back, shoulders, and chest. Calcium deposits may cause hard bumps under the skin. Progressive muscle weakness occurs in the hips, thighs, arms, neck, and shoulders. It is more common among children and women.

Inclusion Body Myositis

Inclusion body myositis is a degenerative muscle disease that occurs when certain proteins clump together. It can involve the muscles of the wrists, fingers, thighs, and foot. It’s usually on one side of the body and may cause swallowing difficulties. It’s more common in men over the age of 50. Many patients end up using a wheelchair within 10 to 15 years of diagnosis.

Necrotizing Autoimmune Myopathy

Necrotizing autoimmune myopathy is a rare condition that causes weakness, especially in the lower body. People who have this disorder often experience dizziness, severe fatigue, and muscle pain when climbing stairs or standing up quickly.  

What Causes Myositis?

It is unclear what causes myositis, but doctors suspect that some types are caused by autoimmune disorders that are triggered by an infection, virus, toxin, or another environmental element.

How is Myositis Diagnosed?

It usually takes multiple tests to confirm a myositis diagnosis, including a complete physical exam, blood tests, an electromyography, and a muscle biopsy. Blood tests may be used to check for inflammation levels and to look for antibodies that attack the cell’s nucleus. An electromyography, or EMG, inserts a tiny needle electrode into the muscle to record electrical messages from nerve endings. Myositis may cause an unusual activity pattern. A muscle biopsy, done by examining a small sample of muscle under a microscope, can also detect inflammation. An MRI scan may detect damaged areas of muscle. Your doctor will use the combination of tests and exams to determine what type of myositis you have.

How is Myositis Treated?

Steroids, taken either by tablets or injections, are the most typical treatment for myositis. They often can reduce inflammation quickly. Your doctor will discuss potential side effects with you, as well as medicine you should take with the steroids to offset potential bone loss.

What you can expect at UTHealth Neurosciences

UTHealth Neurosciences brings together a multidisciplinary team of board-certified, fellowship-trained neurosurgeons, neurologists, researchers, and pain management specialists to help provide relief for even the most complex problems. Your team will share insights, leading to better treatment decisions and outcomes. You will receive expert care, excellent communication, and genuine compassion.

We first investigate nonsurgical treatment options, including medical management, pain management, physical therapy, rehabilitation, and watchful waiting. When surgery is needed, our neurosurgeons routinely employ innovative minimally invasive techniques. Throughout the treatment process, we will work closely with the doctor who referred you to ensure a smooth transition back to your regular care. While you are with us, you will receive expert care, excellent communication, and genuine compassion.

Contact Us

At UTHealth Houston Neurosciences, we offer patients access to specialized neurological care at clinics across the greater Houston area. To ask us a question, schedule an appointment, or learn more about us, please call (713) 486-8000, or click below to send us a message. In the event of an emergency, call 911 or go to the nearest Emergency Room.