Connective Tissue Disorders
Connective Tissue Disorders

Understanding Connective Tissue Disorders

The doctor says your child has a connective tissue disorder. This might be the first time you’ve even heard the phrase. What’s wrong with your child’s body? Is it serious? What does it mean in the long run?

 To understand what connective tissue disorders are, it’s important to understand first what connective tissue is. To do that, it’s helpful to start by thinking about the body’s organs.

How Do Connective Tissue Disorders Start?

 Organs are where some of the body’s most important functions take place—like pumping blood through the heart or breathing air into and out of the lungs. Each organ is made up of several types of tissues that work together, sort of like building blocks. The skeleton is the body’s second-largest organ; the skin is the largest.

 The connective tissues of the skeleton consist of cartilage, bone, tendon, muscle and ligaments. These tissues come together to form the skeleton and allow it to keep its shape and strength so that it can do its job of providing protection, moving, and producing blood (from the bone marrow).

But when your child has a connective tissue disorder, the proteins or components that make up connective tissues can be abnormal for several different reasons. In some cases, it is because they become inflamed or irritated. In other circumstances, it is because there is a change in a gene that affects the protein. When these connective tissues do not function properly, then the organs that they are found in work less effectively and can experience long-term damage.

What Are Some Types of Connective Tissue Disorders?


Connective Tissue Disorders: Why There Are So Many

The body has 78 organs, and the skeleton has 206 bones. Connective tissues are found throughout all of these complex structures. In fact, there are more than 200 of these types of disorders.

Some of the most common connective tissue disorders include:

Rheumatoid arthritis (RA)

Rheumatoid arthritis is the most common autoimmune connective tissue disorder. In an autoimmune disease, the immune system, which normally attacks foreign invaders like viruses and bacteria, instead starts attacking the body, particularly joints that are made up of tendons, ligaments, cartilage, and coverings.

RA can cause pain, swelling, stiffness, limited motion, or impaired joint function.


Like rheumatoid arthritis, scleroderma is also an autoimmune condition. It causes connective tissues to become hard or thick, which can cause pain or swelling in the joints and muscles.

There are two main types of scleroderma: localized and systemic. Localized scleroderma tends to impact mostly the skin and joints. Systemic scleroderma—which is much rarer in children—can impact both the skin and internal organs, particularly the lungs.  

Systemic lupus erythematosus (SLE, or lupus)

Lupus is a disease in which tissue in every organ of the body—such as the brain, lungs, blood, and skin—becomes inflamed. This can cause a wide range of symptoms, from headaches and fatigue to swelling and hair loss. Frequently, early signs include joint pain.

Osteogenesis imperfecta (OI)

Osteogenesis imperfecta is also known as brittle bone disease. This is a genetic disease that is the result of changes in genes that are important to the quality and quantity of bone.

In some cases, it is a new change in an otherwise normal family. Sometimes it is passed on through generations of families. More rarely, unaffected parents each pass on a nonfunctional gene. It causes bones to break easily, even without trauma. It can also cause weak muscles, a curved spine, hearing loss, or brittle teeth.

Ehlers-Danlos syndrome (EDS)

This disorder is actually a group of disorders that results from abnormal collagen—a major protein that forms connective tissues, such as tendon, ligaments, muscles, and bone.
It can cause symptoms such as extremely loose joints, weak muscle tone, scoliosis (a curve in the spine), or very fragile skin that easily tears or bruises, because collagen is also important to the strength of skin.

Children with this condition can have a broad range of health issues, such as small, fragile blood vessels; slow wound healing; easily sustained injuries; and pain. Many of the forms of Ehlers-Danlos syndrome are due to genetic defects, but in other cases, the cause remains unknown.

What Are Some Common Symptoms of Connective Tissue Disorders?

Since there are so many different kinds of connective tissue disorders, signs and symptoms vary widely. However, some of the common symptoms of these disorders include:

  • Fevers (e.g., autoimmune disorders)
  • Pain, stiffness, or weakness in the muscles and joints (e.g., autoimmune disorders)
  • Delayed motor skills development (e.g., OI and EDS)
  • Bone deformities (e.g., OI)
  • Low energy (e.g., autoimmune and EDS)

Certain disorders—like rheumatoid arthritis, scleroderma, and systemic lupus erythematosus—can sometimes cause serious health problems. For instance, they can create abnormalities in the lungs, causing breathing problems like breathlessness or chronic coughing.

 What Causes Connective Tissue Disorders?

Each type of connective tissue disorder has its own potential cause.

For some types—like osteogenesis imperfecta—the disorder might be due to a gene that changed, or mutated. Occasionally, conditions like systemic lupus erythematosus can develop because of a reaction to a medication.

However, many types of connective tissue disorders—like rheumatoid arthritis and scleroderma—have no known cause.