About

Connective tissue diseases (CTD) are Systemic Autoimmune Rheumatic Diseases (SARDs), a group of disorders characterized by inflammation and autoimmune reactions that affect multiple organ systems. These diseases involve the immune system attacking the body’s tissues, leading to widespread inflammation and damage. The most common SARDs are:

  • Systemic Lupus Erythematosus (SLE), a chronic autoimmune disease that can affect the skin, joints, kidneys, brain, and other organs, with symptoms like fatigue, joint pain and swelling, skin rashes (especially a butterfly-shaped rash on the face), photosensitivity, fever, and organ involvement such as nephritis and pericarditis.
  • Systemic Sclerosis (Scleroderma), an autoimmune disease characterized by fibrosis (thickening and hardening) of the skin and internal organs.
  • Sjögren’s Syndrome, that primarily affects the glands that produce saliva and tears.
  • Polymyositis and Dermatomyositis, inflammatory myopathies that cause muscle inflammation and weakness. Dermatomyositis is associated with a distinctive skin rash.
  • Mixed Connective Tissue Disease (MCTD), a disease featuring overlapping symptoms of SLE, Scleroderma, and Polymyositis, with specific autoantibodies (anti-RNP-70). Autoantibodies against cellular components, anti-nuclear antibodies (ANA), are important serological markers for CTD. Target antigens include nucleic acids, cell nuclear proteins and ribonuclear proteins as well as components of the cytoplasm.
3–5%
prevalence of autoimmune disorders in the general population.
10:1
is the women-men ratio for specific autoimmune disorders.

Diagnosis

The diagnosis of CTD uses IFA (Immunofluorescence Assays) products and specific confirmatory tests. The gold standard of ANA determination (serological markers of CTD) is IFA, using human epithelial tumor cells (HEp-2), a stabilized cell line of human larynx carcinoma, known for its high sensitivity and specificity. In the context of CTD diagnosis is critical to identify the antibodies’ specificity. The Alegria monotest strip is a reliable solution offering a wide range of confirmatory tests, helping to save time and reduce reagent waste.

Sebia's Expertise

Sebia offers a reliable diagnostic path from the screening phase to the confirmation, by offering a combined workflow of ANA evaluation, and detection of the related antigens. This is done by using Sebia’s IFA test systems, the Alegria Monotest random access solution, and completed by the ELISA tests for high throughput tasks.