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Laboratory value | Result |
Hemoglobin | 10.2 g/dL |
Hematocrit | 31% |
Platelet count | 350,000/mm3 |
Leukocyte count | 3,000/mm3 |
Erythrocyte sedimentation rate | 52 mm/h |
Antinuclear antibodies | Positive |
Rheumatoid factor | Negative |
Anti-dsDNA | Negative |
Anti-Ro/La | Positive |
Sjogren's syndrome, named after Dr. Henrik Sjogren who first identified it, is a common autoimmune disorder, typically occurring in women.
In Sjogren’s syndrome, the body’s immune cells go rogue and start attacking various exocrine glands, which are glands that pour their secretions into a duct; most commonly the salivary glands and the lacrimal, or tear, glands.
Normally, the cells of the immune system are ready to spot and destroy anything foreign pathogens that could cause the body harm.
Immune cells called antigen-presenting cells, which include macrophages and dendritic cells, latch onto pathogens and engulf them - literally swallowing them up.
Pieces of the pathogen called antigens are then presented on a major histocompatibility complex class II molecule, or MHC-class II molecule - which is like a serving platter for antigens. An antigen presenting cell then searches for a T cell that can bind to the antigen.
Once found, binding to the antigen helps activate this T cell, which then releases proinflammatory cytokines, or signaling molecules, that recruit more immune cells - ultimately leading to inflammation.
The exact cause for Sjogren's syndrome is unknown, but it seems to be related to both genetic and environmental factors.
Genetic factors include genes which code for specific types of MHC class II molecules, called human leukocyte antigen, or HLA genes. Specifically HLA- DRW52, HLA- DQA1, or HLA- DQB1.
Environmental factors include an infection of exocrine glands like the salivary and lacrimal glands. Infections can damage the cells of the salivary gland, and expose their cell components, including their DNA, RNA, and histones to circulating immune cells.
These cell components get picked up by antigen-presenting cells, and presented to T-cells. In individuals with Sjogren's syndrome, a T cell gets inappropriately activated by these nuclear components, and considers them to be foreign nuclear antigens.
Sjogren's syndrome is an autoimmune disease in which the body's immune cells attack various moisture-producing exocrine glands, which normally pour their secretions into various ducts in the body, such as the salivary and the lacrimal glands. This results in the development of a dry mouth and dry eyes. Other symptoms can include dry skin, a chronic cough, vaginal dryness, numbness in the arms and legs, feeling tired, and muscle and joint pains. Treatment of Sjogren's syndrome typically involves medications to suppress the immune response, like corticosteroids; and also medications that increase the exocrine secretions like pilocarpine.
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