Exists when the immune system fails to recognize the body's own cells, and begins to attack them as if they were foreign.
Autoimmunity
Diseases caused by the body producing an inappropriate immune response against its own tissues.
Autoimmune disorders
Autoimmune disorders fall into two general types:
Systemic autoimmune diseases and localized
Disorders that damage many organs.
System autoimmune disease
Disorders where only a single organ or tissue is directly damaged by the autoimmune process
Localized
Systemic autoimmue diseases include
Rheumatoid arthritis and juenile RA, Lupus, Scleroderma, Scleroderma, Sjorgren's syndrome, Goodpasture's syndrome, Wegener's granulomatosis, Polymyalia Rheumatica, and Guillain-Barre syndrome.
Rheumatoid arthritis (RA) and Juvenile RA (JRA)
Joints; less commonly lungs and skin.
Lupus (Systemic Lupus Erythematosus)
Skins, joints, kidneys, heart, brain, red blood cells, and other
Scleroderma
Skin, intestine, less commonly lungs
Sjogren's syndrome
Salivary glands, tear glands, and joints
Goodpasture's syndrome
Lungs and kidneys
Wegener's granulomatosis
Blood vessels, sinuses, lungs, and kidneys
Polymyalgia Rheumatica
Large muscle groups
Guillain-Barre syndrome
Nervous system
Localized Autoimmune Diseases
Type 1 diabetes mellitus, Hashimoto's thyroiditis, Graves's disease, Celiac disease, Crohn's disease, Ulcerative colitis, Multiple sclerosis, Addison's disease, primary biliary cirrhosis, sclerosing cholangitis, autoimmune hepatitis, temporal arteritis/Gi
Type 1 Diabetes Mellitus
pancreas islets
Hashimoto's thyroiditis and Graves' disease
Thyroid
Celiac disease, Crohn's disease, and ulcerative colitis
GI tract
Multiple sclerosis
There is still some debate whether MS is an autoimmune disease
Addison' disease
adrenal
Primary biliary cirrhosis, sclerosing cholangitis, autoimmune hepatitis
liver
Temporal arteritis/giant cell arteritis
Arteries of the head and neck
Usually prevented by the normal functioning of immunologic regulatory mechanisms.
Autoimmune disease
When these controls dysfunction, antibodies to self antigens may be produced and.......
bind to antigens in the circulation to form circulating immune complexes and bind to antigens deposited in specific tissue sites.
An individual may develop an autoimmune response in a variety of ___________.
immunogenic stimuli
Autoimmune responses maybe caused by
-Antigens that do not normally circulate in the blood
-Altered antigens
-A foreign antigen that is shared or cross-reactive with self-antigens or tissue components
-Mutation of immunocempetent cells to acquire a responsive to self-antigens
-Loss of the im
A progressive inflammatory disease of the joints
Rheumatoid arthritis (RA)
Clinical symptoms of rheumatoid arthritis
The disease can be very mild or severe. Severe cases can maifest as a destructive polyarthritis where the hands and feet are severely deformed.
Serological findings of RA
Low serum iron and low or normal iron-binding capacity, Mild to moderate decrease in serum albumin.
During the acute and chronic phases the following are usually elevated:
Erythrocyte sedimentation rate, Gamma globulins (commonly IgM and IgG) Platelet count often (roughly in proportion to the severity of overall joint inflammation).
Rheumatoid Factor in RA
An IgM antibody that reacts against a patient's own IgG antibodies, demonstrable in 70-80% of patients with RA. Not a cause of rheumatoid arthritis but produced during the course of the disease. High titers associated with severe rheumatoid disease.
Antinuclear Antibodies in RA
Demonstrable in 20% of patients. Titers lower than in SLE (Systemi lupus erythematosus).
Complement Levels in RA
Usually normal except in those with vascultitis. Depressed hemolytic complement levels found in less than 1/3 patients. Usually found in patients with very high levels of rheumatoid factor (RF) and immune complexes.
Felty's Syndrome
Association of RA with splenomegaly and leukopenia. Almost always develops in patients with a high-tier rheumatoid factor (RF) assay, a positive antinuclear antibodies (ANA) assay, and rheumatoid nodules. Joint fluid examination is valuable, reflecting ab
The two most common autoimmune diseases that affect the thyroid:
Hashimoto's thyroiditis (also called chronic autoimmune thyroiditis) - characterized by an underactive thyroid and Grave's diseasem, which is characterized by an overactive thyroid.
Signs and Symptom of Hashimoto's Thyroiditis
Thyroiditis, hypothyroidism, and a large and rubbery thyroid gland (goiter).
Thyroiditis
Inflammation of the thyroid gland
Hypothyroidism
Underactive thyroid
Symptoms of hypothyroidism
Dry skin, decreased sweating, puffy face with edematous eyelids, yellow tinge pallor, weight gain, and dry brittle hair.
Signs and symptoms of Grave's Disease
Manifests by overproduction of thyroid hormones. Goiter that is soft instead of rubbery. Leads to hyperthyroidism (overactive thyroid).
Symptoms of hyperthyroidism
Nervousness, insomnia, rapid heartbeat, fatigue, restlessness, and hypertrophy of eye muscles causes eyeball to bulge out..
Important proteins, enzyme, and hormones of the thyroid include
Thyroglobulin, thyroid peroxidase (TPO), Thyroid stimulating hormone (TSH), and triiodothyronine and thyroxine hormones.
Thyroglobulin
protein which is the precursor of thyroid hormones
Thyroid peroxidase (TPO)
Enzyme that plays an important role in the production of thyroid hormones
Hashimoto's thyroiditis hormone test
Slight increase in the plasma TSH concentration (early phase). Fall of thyroid hormones thyroxine and serum triodothyronine (later phases).
Hashimoto's Thyroiditis
The following autoantibodies found in moderate to high titers of 50% of patients are antithyroglobin, antimicrosomal antibodies (considered more diagostic). More than 90% have anti-TPO (autoantibody to TPO)
Grave's Disease Hormone test
Decreased levels of TSH. Elevated levels of hormones triiodothyronine and thyroxine. Increased uptake of radioactive iodine (confirmatory test). Anti-TPO antibodies found in 50% of patients.
Systemic Lupus Erythematosus Overview
Classic model of autoimmune disease. Chronic systematic inflammatory diseases. Incidence 1 in every 2000 individuals (tripled over last 4 decades). Mostly affects women. Onset usually between 20-40 years. Course of disease is variable. Usually follows a c
Most common causes of death with SLE
Renal failure and infectious complications.
Signs and syptoms of SLE are __________ and _________.
Diverse, nonspecific
Early signs of SLE
Fatigue, weight loss, malaise fever, and loss of appetite
Joint involvement with SLE
Seen in 90% of patients and includes joint pain or arthritis.
Butterfly rash in SLE
Seen in more than 40% of patients. Rash in shape of butterfly across nose and cheeks.
SLE infections
Increased susceptibility to common and opportunistic infections.
SLE can involve the following organ systems:
Renal system, cardiovascular system, GI system, nervous system, and musculoskeletel system.
Antinuclear Antibodies (ANA)
Hallmark autoantibody of systemic lupus erythematosus (SLE). Heterogeneous group of immunoglobins that react with whole nucleus or nuclear components such as DNA and nuclear proteins. They are true autoantibodies. They are found in other diseases such as
Potential blood test finding for SLE
Moderate anemia, lymphocytopenia, and thrombocytopenia.
Serological manifestations of SLE
High levels of antinuclear antibodies (ANA), Immune complexes, complement-level depression, tissue deposition of Igs and complement and other autoantibodies.