Mixed Connective Tissue Disease

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Mixed Connective Tissue Disease

Question:

I was diagnosed with rheumatoid arthritis almost 4 years ago. Multiple treatments have been ineffective. I just changed doctors and the new team of specialists mentioned "mixed connective tissue disease" as a possible diagnosis. Can you tell me more about this and its relationship to rheumatoid arthritis?

Answer:

Mixed Connective Tissue Disease (MCTD) is a rare disorder. It shares the features of several conditions, including lupus, myositis (muscle inflammation) and scleroderma. These conditions are all autoimmune diseases, which means the body's defense system mistakenly attacks the body's own tissues. MCTD seems to be an autoimmune disease, too.

Symptoms of MCTD may begin with arthritis. So, doctors may correctly diagnose rheumatoid arthritis in a person with joint pain and swelling in multiple joints, especially joints in the hands and wrists. Morning stiffness is also typical.

If other symptoms develop over time, the patient's diagnosis may "evolve" into MCTD. Symptoms may include:

• A rash on the face, chest or limbs

• Muscle weakness and pain

• Color changes in the fingers triggered by cold (Raynaud's phenomenon)

• Skin thickening, especially on the fingers, hands, forearms and face

• Chest pain made that worsens when taking a deep breath or shortness of breath with exertion

• Fever and fatigue

Blood and urine tests will look for anemia, kidney or muscle inflammation, and an abnormal antibody called anti-ribonuclear protein. These all point toward MCTD.

Treating MCTD depends on which body parts are affected. Corticosteroids, hydroxychloroquine, methotrexate and other immunosuppressive drugs are commonly recommended. Drugs to open up blood vessels, such as nifedipine, are often prescribed for Raynaud's phenomenon. Cyclophosphamide or cellcept may be prescribed if kidney inflammation is present. Intravenous immunoglobulin, an injection of antibodies collected from blood donors, may be effective for muscle inflammation.

Most people with rheumatoid arthritis or MCTD can be effectively treated. However, it may take a while to identify the best therapy or combination of treatments.

Robert Shmerling, M.D., is associate physician and clinical chief of rheumatology at Beth Israel Deaconess Medical Center and an associate professor in medicine at Harvard Medical School. He is an active teacher in the Internal Medicine Residency Program, serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program and has been a practicing rheumatologist for over 25 years.

Last updated:	July 20, 2009