Connective Tissue Disease: Types, Symptom, Treatment, Causes, Prevention

The connective tissues are the structural portions of the body that supports the body by holding the cells. It is known as cellular glue, as it helps in shape formation of the tissues. The connective tissues are made up of two types of protein molecules:

• Collagen- The collagen proteins are classified into various types and the body tissues constitutes of them in various amount.
• Elastin- Elastin is the second type of protein molecules which has the potential to stretch like a spring. It is a major component of the tissues that attach bones and skin- ligaments.

The collagen and elastin may get damaged due to inflammation leading to connective tissue disease. The connective tissue disease refers to disorder in the connective tissues that cause multiple damages in the body.

The damage in the connective tissue resulting into multiple damages into the related organs of the body is called connective tissue disease.

The disorders include problems in various organs like lungs, heart, kidneys, eyes etc. and systems like gastrointestinal tract or the immune system in the body.

The types of connective tissue disease can majorly be classified into two types. These two types can be further classified into subtypes. The types are:

• Inherited Disorders of Connective Tissue: These types of disorders are a diverse group of diseases. They are also known as Heritable Disorders of Connective Tissues (HDCTs), which primarily affect the joints, skin and cardiovascular systems. The severity of the musculoskeletal phenotype is dependent on:
• The role and function of the damaged protein on the musculoskeletal structure.
• The type and intensity of mutation.

These types of disorders can be further classified into:

• Epidermolysis Bullosa (EB) –EB usually occurs since birth and is caused due to damaged proteins of the skin. The abnormalities of EB includes:
  • Hyperextensible skin- resulting into tearing or friction from clothing.
  • Dysfunction in the respiratory tract, digestive tract and the bladders.
• Ehlers-Danlos Syndrome (EDS) – EDS might be caused due to mutation in Type V Collagen gene, which is crucial in the assembly of proper skin matrix collagen fibrils and the basement of membrane. EDS is a group of more than 10 disorders. Various abnormalities are seen, including:
  • Hypermobile joints
  • Week blood vessels
  • Hyperextensible skin
  • Bleeding gums
• Osteogenesis Imperfecta- Osteogenesis Imperfecta occurs due to mutation in the Type I collagen gene, responsible for the organic bone matrix. The amount or the quality of protein in Type I collagen gene gets diminished. This condition has various subtypes. Some common abnormalities include:
  • Thin skin
  • Brittle bones
  • Curved spine
  • Low muscle mass
  • Impairment in hearing
  • Weak teeth- it may break easily
  • Breathing problems
  • The white areas of the eyes get blue or gray.
• Marfan Syndrome- Marfan syndrome is caused due to multiple mutations in fibrillin-1 gene on chromosome 15q21. It is autosomal dominant as it affects the bones, blood vessels, ligaments and eyes. Various abnormalities include:
  • Ascending aorta- which is the largest artery in the body.
  • Suspensory ligament of the lens.
  • Long bones.

The occurrence of Marfan syndrome is 1 in 10,000.

• Autoimmune Diseases:The autoimmune diseases are caused by the antibodies generated by the immune system of the body. These antibodies damage their own body tissues. The autoimmune disease can be further classified into:
  • Rheumatoid Arthritis- Rheumatoid Arthritis also known as seropositive arthritis caused by the inflammatory immune system. Various abnormalities include:
    • Thick Synovium
    • Morning stiffness in the body
    • Pain and swelling in the joints
    • Anemia
    • Fatigue
    • Fever
• Systemic Lupus Erythematosus – Systemic Lupus Erythematous is caused due to inflammation in the internal organs, joints or skin. The symptoms of SLE include:
  • Rashes on the cheeks and bridge of the nose
  • Anemia
  • Mouth ulcers
  • Hair loss
  • Lack of memory and concentration
• Scleroderma- Scleroderma is a group of disorders causing tight, thick layer of skin, damage to the organs and the buildup of scar tissue. Scleroderma can further be classified into:
  • Localized scleroderma- It is found in skin and muscle below it.
  • Sytemic Sclerosis- It is found in blood vessels and various organs.
• Polymyositis and Dermatositis- Polymyositis are related to inflammation in muscle and Dermatositis is related to skin inflammation including skin around eyes and hands. These two disorders are interrelated. The symptoms include:
  • Fatigue
  • Fever
  • Breathing problems
  • Muscle weakness
  • Weight loss
• Sjogren’s Syndrome- Sjogren’s syndrome is a chronic disorder that affects the moisture-producing glands like mouth and eyes due to damage caused by the immune system. The symptoms consists of:
  • Dry mouth
  • Dry eyes
  • Fatigue
  • Pain in the joints
  • Risk of lymphoma
  • Damage in lungs, kidneys and blood vessels
  • Nerve problems.
• Vasculitis- The inflammation in the blood vessels causes Vasculitis. It includes 20 different types of conditions caused due to damaged blood vessels. It obstructs blood flow to other tissues and other organs in the body.
• Other Types of Connective Tissue Diseases: Besides, the above mentioned types, the other types of Connective tissue disease includes:
  • Scurvy-this is a type of connective tissue disorder that is caused due to defective collagen growth and repair due to deficiency of Vitamin C in the body. The symptoms include:
    • Gum bleeding
    • Fatigue
    • Iron deficiency
    • Joint effusions
    • Ecchymosis

The abnormalities include:

• Stunted bone growth
• Bow legs
• Reduced bone formation
• Defective structural arrangement
• Swelling and pain in joints

• Spondyloepiphyseal Dysplasia- this is a type of connective tissue disorder that is caused due to genetic defect in type II collagen. The abnormalities include:
  • Abnormal epiphyseal development in the lower and upper parts of the body.
  • Scoliosis: Sharply curved apex over a small number of vertebrae.
  • Retinal detachment
  • Respiratory problems
• Kniest Syndrome- This is a type of connective tissue disorder that is caused due to damage in the type II collagen. The abnormalities related to Kniest syndrome include:
  • Scoliosis/ Kyphosis
  • Disproportionate Dwarfism
  • Joint stiffness
  • Impairment in hearing

The symptoms of connective tissue disease are based on its type. However, the common symptoms include:

• Fatigue
• Fever
• Pain and swelling in joints
• Pain in muscles
• Weakness
• Stiffness.

The specific causes of Connective tissue diseases are unknown. However, the damage in the genetic patterns and environmental factors play a vital role in causing the connective tissue disease.

The diagnosis of Connective tissue disease can be done with the help of the following:

• Laboratory Tests–
  • Blood Tests: The blood test includes ESR and CRP. The tests help in analyzing the genetic mutation and abnormalities in the blood cells.
• Imaging Techniques–
  • X-ray: To find out the abnormalities in the bone.

There is no certain type of treatment for connective tissue disease. However, to treat its signs and symptoms following can be undertaken:

• Medication:It helps in treating the symptoms of connective tissue disease. However, a continuous medication is required if the signs are more critical. The medications to treat the symptoms of connective tissue disorder includes:
  • Corticosteroids- It can help in reducing inflammation and prevents from damaging healthy cells by the immune system.
  • Calcium channel blockers- It may help in relaxing the muscles on the walls of blood vessels.
  • Pulmonary hypertension medications- Sildenafil like Viagra can be prescribed.
  • Immunosuppressants- It can help in normal functioning of the immune system.
  • Antimalarial drugs- It can help in treating mild connective tissue disease and may prevent flare-up.

The prevention of Connective tissue disease can be divided into two stages:

• Primary- The primary prevention of Connective tissue disease includes modified lifestyle and environmental factors. Unhealthy food and smoking should be avoided to minimize the risks of kidney disorders.
• Secondary- Aggressive medications to treat autoimmune disease are a secondary way of prevention. However, this should be administered only on patients who are asymptomatic to critical disease.

The connective tissue diseases are a group of disorders and are associated to various abnormalities in the skin and bones. Proper and timely care can help in preventing critical consequences of the disease.