What are connective tissue diseases?

A connective tissue disease is any disease that affects the parts of the body that connect the structures of the body together.

Connective tissues are made up of two proteins: collagen and elastin. Collagen is a protein found in the tendons, ligaments, skin, cornea, cartilage, bone, and blood vessels. Elastin is a stretchy protein that resembles a rubber band and is the major component of ligaments and skin. When a patient has a connective tissue disease, the collagen and elastin are inflamed. The proteins and the body parts they connect are harmed.

What are the different types of connective tissue diseases?

There are several different types of connective tissue diseases. They can be inherited or caused by environmental factors. Connective tissue diseases include, but are not limited to:

  • Rheumatoid arthritis (RA): Rheumatoid arthritis is one of the most common connective tissue diseases and can be inherited. RA is an autoimmune disease, meaning the immune system attacks its own body. In this systemic disorder, immune cells attack and inflame the membrane around joints. It also can affect the heart, lungs, and eyes. It affects many more women than men (an estimated 71% of cases).
  • Scleroderma: An autoimmune condition that causes scar tissue to form in the skin, internal organs (including the GI tract), and small blood vessels. It affects women three times more often than men throughout life, occurring at a rate of 15 times greater for women during childbearing years.
  • Granulomatosis with polyangiitis (GPA), formerly called Wegener’s granulomatosis: A form of vasculitis (inflammation of the blood vessels) that affects the nose, lungs, kidneys, and other organs.
  • Churg-Strauss syndrome: A type of autoimmune vasculitis that affects cells in the blood vessels of the lungs, gastrointestinal system, skin, and nerves.
  • Systemic lupus erythematosus lupus (SLE): A disease that can cause inflammation of the connective tissue in every organ of the body, from the brain, skin, blood, to the lungs. It is nine times more common in women than in men.
  • Microscopic polyangiitis: An autoimmune disease that affects cells in blood vessels in organs throughout the body. This is a rare condition.
  • Polymyositis/dermatomyositis: A disease characterized by inflammation and degeneration of the muscles. When the condition also affects the skin, it is called dermatomyositis.

How do connective tissue diseases affect the lungs and breathing?

One of the most serious impacts of connective tissue disease is on the pulmonary system. The types of connective tissue diseases mentioned above can involve the lungs and affect breathing.

Here is an overview:

  • RA: Although RA mainly affects the joints, it can cause serious complications that affect the lungs. These include painful breathing due to inflammation of the lung lining and shortness of breath because inflammation of the lining causes fluid to accumulate in the lungs. RA can also cause lung nodules (spots) called rheumatoid nodules to form. These usually do not cause symptoms. A more common effect of RA on the lungs is the scarring of the tissue due to the inflammation. Symptoms of this may include shortness of breath, a chronic cough, weakness, and fatigue. Treatment for pulmonary complications of rheumatoid arthritis includes removing excess fluid from the lungs and using medications to suppress the immune system that will decrease the inflammation in the lungs.
  • Scleroderma: About 80% of all patients with scleroderma have pulmonary complications. Without treatment, lung involvement is the leading cause of death from scleroderma. Scleroderma can cause inflammation of the lung tissue, lung scarring, and injury to the blood vessels in the lungs. Symptoms of these include a feeling of breathlessness and fatigue. Treatment includes the use of immune-suppressing medications, regular exercise, and the use of supplemental oxygen if needed.
  • GPA: This disease mostly affects the upper respiratory tract (sinuses and nose), as well as the breathing tubes and the lung tissue by causing inflammation and damage to the blood vessels in those organs. Pulmonary symptoms include a cough that might include bloody phlegm, chest discomfort with or without shortness of breath, nose bleeds, and a persistent runny nose. Treatment for this condition is primarily the use of anti-inflammatory and immune-suppressing medications.
  • Churg-Strauss syndrome: This condition that affects blood vessels in the lungs can have serious breathing complications. It first presents with asthma-like symptoms, including shortness of breath and the inability to catch your breath. Other symptoms can include coughing up blood. The lungs can also develop scarring as well as accumulate fluid. Treatment includes the use of immune-suppressing drugs, usually prednisone. This is very effective in treating the syndrome.
  • SLE: More than 50% of patients with SLE have pulmonary complications. Pleurisy (inflammation of the lining of the lung) is the most common problem. Other complications include the build-up of fluid around the lung and scarring of the lung tissue. SLE can also cause a condition called lupus pneumonitis, an inflammation of the lungs that can be chronic. Symptoms of these conditions include shortness of breath, chest pain, difficulty breathing, and coughing. Lupus pneumonitis may cause a fever. Treatment includes immune-suppressing drugs.
  • Microscopic polyangiitis: This condition is very similar to but rarer than, GPA and causes inflammation of the blood vessels in the lungs. Pulmonary problems are similar, including bloody cough and shortness of breath. Treatments are also anti-inflammatory and immune-suppressing medications.
  • Polymyositis/dermatomyositis: Polymyositis can cause scarring of the lungs, which causes symptoms such as shortness of breath and coughing. The disease can also affect the muscles surrounding the lungs, which can make it difficult to take deep breaths and can rarely lead to respiratory failure. Treatments include the use of immune-suppressing drugs, oxygen, and physical therapy.

Call your doctor right away if you experience any of these symptoms, or if you are already diagnosed with a connective tissue disease and are experiencing breathing problems. With proper treatment, many pulmonary complications of connective tissue disease can be managed along with other complications of the disease.

Last reviewed by a Cleveland Clinic medical professional on 01/16/2015.


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