Overlap syndrome
Encyclopedia
An overlap syndrome is an autoimmune disease
of connective tissue
in which the patient presents with symptoms of two or more diseases. As much as 25% of all patients with connective tissue disease
show signs of an overlap syndrome.
Examples of overlap syndromes include MCTD and scleromyositis
, but the exact diagnosis depends from which diseases the patient shows symptoms. In overlap syndromes, features of systemic lupus erythematosus
(SLE), systemic sclerosis, polymyositis
, dermatomyositis
, rheumatoid arthritis
(RA) and Sjögren's syndrome
are found often.
Autoimmune disease
Autoimmune diseases arise from an overactive immune response of the body against substances and tissues normally present in the body. In other words, the body actually attacks its own cells. The immune system mistakes some part of the body as a pathogen and attacks it. This may be restricted to...
of connective tissue
Connective tissue
"Connective tissue" is a fibrous tissue. It is one of the four traditional classes of tissues . Connective Tissue is found throughout the body.In fact the whole framework of the skeleton and the different specialized connective tissues from the crown of the head to the toes determine the form of...
in which the patient presents with symptoms of two or more diseases. As much as 25% of all patients with connective tissue disease
Connective tissue disease
A connective tissue disease is any disease that has the connective tissues of the body as a target of pathology. Connective tissue is any type of biological tissue with an extensive extracellular matrix that supports, binds together, and protects organs...
show signs of an overlap syndrome.
Examples of overlap syndromes include MCTD and scleromyositis
Scleromyositis
Scleromyositis or the PM/Scl overlap syndrome is a complex autoimmune disease . Patients with scleromyositis have symptoms of both systemic scleroderma and either polymyositis or dermatomyositis, and is therefore considered an overlap syndrome...
, but the exact diagnosis depends from which diseases the patient shows symptoms. In overlap syndromes, features of systemic lupus erythematosus
Systemic lupus erythematosus
Systemic lupus erythematosus , often abbreviated to SLE or lupus, is a systemic autoimmune disease that can affect any part of the body. As occurs in other autoimmune diseases, the immune system attacks the body's cells and tissue, resulting in inflammation and tissue damage...
(SLE), systemic sclerosis, polymyositis
Polymyositis
Polymyositis is a type of chronic inflammation of the muscles related to dermatomyositis and inclusion body myositis.-Signs and symptoms:...
, dermatomyositis
Dermatomyositis
Dermatomyositis is a connective-tissue disease related to polymyositis and Bramaticosis that is characterized by inflammation of the muscles and the skin.- Causes :...
, rheumatoid arthritis
Rheumatoid arthritis
Rheumatoid arthritis is a chronic, systemic inflammatory disorder that may affect many tissues and organs, but principally attacks synovial joints. The process produces an inflammatory response of the synovium secondary to hyperplasia of synovial cells, excess synovial fluid, and the development...
(RA) and Sjögren's syndrome
Sjögren's syndrome
Sjögren's syndrome , also known as "Mikulicz disease" and "Sicca syndrome", is a systemic autoimmune disease in which immune cells attack and destroy the exocrine glands that produce tears and saliva....
are found often.