Lecture 12 Hormones Flashcards
What are the four autoimmune laboratory tests?
erythrocyte sedimentation rate, c-reactive protein, antinuclear antibody, rheumatoid factor
What are the four autoimmune laboratory tests?
erythrocyte sedimentation rate, c-reactive protein, antinuclear antibody, rheumatoid factor
What are the indications for an ESR?
erythrocyte sedimentation rate; sed rate; does not tell you a diagnosis just tells you that something is wrong; marker for inflammation, infection, neoplasm, and tissue necrosis
What is the pathophysiology behind ESR test?
erythrocytes are negatively charged and therefore repel eachother; inflammation and infection can increase release of acute phase reactants therefor increasing the positive charge; the RBCs start to stack in the test tube making the ESR higher
In the case of inflammation and infection what are the two acute phase reactants that the body releases?
fibrinogen and immunoglobulin’s
What is the normal value for an ESR?
0-20 mm/h
What is the normal value for C-reactive protein?
0-10 mg/dL
What is the function of C-reactive protein?
recognizes and responds to inflammatory mediators and target damages tissue for clearance
What is the purpose of CRP-HS?
can detect small enough amounts of CRP to stratify risk for cardiac disease or future cardiovascular events
What is the ANA test important for diagnosing?
systemic lupus erythematosus (SLE)
What are the manifestations of SLE?
butterfly rash!, fatigue, weight loss, arthralgia. myalgias, lymphadenopathy, multiple organ involvement
What are the negative and positive values for ANA?
less than 1:40 dilution is negative…
greater than 1:160 is positive
What are some of the other diseases one could have with a positive ANA test?
SLE, progressive systemic sclerosis, rheumatoid arthritis, siogren syndrome, dermatomyoaitia, polyarteritis
What are the manifestations of scleroderma?
fatigue, arthralgia, myalgia, skin thickening and hardening, digital ulcers
What percent of people with a positive ANA will actually have lupus?
11-13%; shows that people with other disease can present with a positive ANA test
What are the systemic manifestations of rheumatoid arthritis?
fatigue, cardiovascular, renal, and others…
What is the normal value for rheumatoid factor?
How does rheumatoid arthritis differ from osteoarthritis?
it is caused by autoantibody destruction of joint tissue and has systemic manifestations
What is the rheumatoid factor predominantly composed of?
IgM antibodies that are directed against the portion of IgG antibody known as the Fc fragment
What disease is the rheumatoid factor increased with?
rheumatoid arthritis, other autoimmune disease, chronic infections, such as hepatitis, malignancy
What are the lab tests ordered for the thyroid gland?
TSH, T4, Free T4, T3, Free T3
What are the normal values for the thyroid stimulating hormone?
0.5-5.0 uIU/ mL
What is control of the thyroid gland controlled by?
hypothalamus and pituitary gland
What are the indications for an ESR?
erythrocyte sedimentation rate; sed rate; does not tell you a diagnosis just tells you that something is wrong; marker for inflammation, infection, neoplasm, and tissue necrosis
What is the pathophysiology behind ESR test?
erythrocytes are negatively charged and therefore repel eachother; inflammation and infection can increase release of acute phase reactants therefor increasing the positive charge; the RBCs start to stack in the test tube making the ESR higher
In the case of inflammation and infection what are the two acute phase reactants that the body releases?
fibrinogen and immunoglobulin’s
What is the normal value for an ESR?
0-20 mm/h
What is the normal value for C-reactive protein?
0-10 mg/dL
What is the function of C-reactive protein?
recognizes and responds to inflammatory mediators and target damages tissue for clearance
What is the purpose of CRP-HS?
can detect small enough amounts of CRP to stratify risk for cardiac disease or future cardiovascular events
What is the ANA test important for diagnosing?
systemic lupus erythematosus (SLE)
What are the manifestations of SLE?
butterfly rash!, fatigue, weight loss, arthralgia. myalgias, lymphadenopathy, multiple organ involvement
What are the negative and positive values for ANA?
less than 1:40 dilution is negative…
greater than 1:160 is positive
What are some of the other diseases one could have with a positive ANA test?
SLE, progressive systemic sclerosis, rheumatoid arthritis, siogren syndrome, dermatomyoaitia, polyarteritis
What are the manifestations of scleroderma?
fatigue, arthralgia, myalgia, skin thickening and hardening, digital ulcers
What percent of people with a positive ANA will actually have lupus?
11-13%; shows that people with other disease can present with a positive ANA test
What are the systemic manifestations of rheumatoid arthritis?
fatigue, cardiovascular, renal, and others…
What is the normal value for rheumatoid factor?
less than 30
How does rheumatoid arthritis differ from osteoarthritis?
it is caused by autoantibody destruction of joint tissue and has systemic manifestations
What is the rheumatoid factor predominantly composed of?
IgM antibodies that are directed against the portion of IgG antibody known as the Fc fragment
What disease is the rheumatoid factor increased with?
rheumatoid arthritis, other autoimmune disease, chronic infections, such as hepatitis, malignancy
What are the lab tests ordered for the thyroid gland?
TSH, T4, Free T4, T3, Free T3
What are the normal values for the thyroid stimulating hormone?
0.5-5.0 uIU/ mL
What is control of the thyroid gland controlled by?
hypothalamus and pituitary gland
What is the thyrotropin- releasing hormone?
it is synthesized in the hypothalamus and transported to the pituitary where is stimulates the secretion of TSH
What can T3 and T4 increase?
myocardial contractility and heart rate, mental alertness, ventilator drive, bone turnover, GI motility
Why would you use the TSH test in conjunction with T3 and T4?
can identify origin of thyroid dysfunction, thyroid gland dysfunction or central
What is primary hypothyroidism and what are the causes?
defect in the thyroid gland; autoimmune thyroiditis (Hashimoto’s thyroiditis) is most common cause
What is secondary hypothyroidism and what are the causes?
less common than primary; decreases the secretion of TSH from pituitary or decrease TRH from hypothalamus; pituitary tumor, post-partum pituitary necrosis
What are the symptoms of hypothyroidism?
fatigue, dull mentation, dry skin, weight gain, bradycardia, constipation, cold intolerance
In hypothyroidism what happens to your TSH levels?
TSH level goes up
What does the thyroid gland produce?
T3 and T4; produced 90% T4 and 10% T3
Which thyroid hormone is more metabolically active?
T3
How can T3 be formed in the tissues?
by conversion of T4 to T3
What are the genetic and environmental causes of hashimoto’s thyroiditis?
hypothyroidism, thyroid failure, +/- goiter, follicular destruction
What are the genetic and environmental causes of Grave’s disease?
hyperthyroidism, goiter, orbitopathy, pretibial myxedema
What is the primary method for identifying autoimmune conditions?
identifying specific autoantibodies to each disease; also can evaluate acute phase reactants such as c-reactive protein and erythrocyte sedimentation rate
What is Roulaeux?
stacking of RBCs
What is a Westergren tube?
a sedimentation tube used in sed rate test
What are some factors that can interfere with ESR results?
microcytosis or anemia can increase ESR; polycythemia can decrease ESR; abnormally shaped RBCs can decrease ESR
What is the ESR that indicates infections?
if over 100 mm/hr
What is mild C-reactive protein?
mild respiratory infection, pregnancy, post-exercise, obesity, depression
What is moderate C-reactive protein?
myocardial infarction, malignancy, autoimmune disease, rheumatoid arthritis
What is marked C-reactive protein?
overwhelming bacterial infection, severe trauma
What is the pathophysiology behind ANA test?
antinuclear antibodies are identified through the use of indirect immunofluorescence; sample is diluted and the highest dilution at which the antinuclear antibodies are detected is reported as a result; the end point occurs when fewer than half the cells show antibody fluorescence
What are the different patterns in an ANA test?
peripheral, diffuse, speckled, nucleolar
What are the manifestations of polymyositis/ dermatomyositis?
proximal skeletal muscle weakness, pulmonary disease, dysphagia, polyarthritis, dermatologic manifestations
What are other autoantibodies that can be measured and are more specific for SLE?
anti-phospholipid antibodies, anti-double-stranded DNA, anti-smith antibody
What are other autoantibodies that can be measured and are more specific for Sjogren’s Syndrome?
anti-RO/ SSA, and Anti-LA/ SSB
What antibodies is Rheumatoid factor predominantly composed of?
IgM antibodies directed against the portion of an IgG antibody known as the Fc fragment; can be caused by other antibodies against the IgG Fc fragment
What percent of people with rheumatoid arthritis have rheumatoid factor?
60-80%
What is the rheumatoid factor that is measured in lab tests?
IgM RF
In predicting hypothyroidism or hyperthyroidism what should you measure?
TSH and more specifically serum free T4
How can you differentiate between primary and secondary hypothyroidism?
if both TSH and free T4 is decreased then there may be a disorder of hypothalamus or pituitary gland which is secondary hypothyroidism
What may a patient present with if they have subclinical hypothyroidism?
may have high normal or mildly elevated TSH with a normal free T4; there are nonspecific symptoms
What is hyperthyroidism caused by?
increased secretion of thyroid hormones from thyroid gland
What is the most common form of hyperthyroidism?
Grave’s Disease
What is Grave’s Disease caused by?
autoantibodies (TRAb) that bind and activate TSH receptors of the thyroid gland -> leads to an inhibitory effect on the hypothalamic-pituitary axis and TSH level decreases
What are some causes of hyperthyroidism?
Grave’s Disease, Hyperplasia of thyroid cells caused by toxic adenoma or toxic multinodular goiter, iodine rich medication such as amiodarone
What are some symptoms of hyperthyroidism?
anxiety, tremors, palpitations, perspiration, heat intolerance, weight loss, hyperdefacation
What are the antibodies that have been found to be associated with autoimmune thyroid conditions such as Hashimoto’s thyroiditis and Grave’s Disease?
thyroglobulin antibodies, thyroid peroxidase antibodies, thyrotropin (TSH) receptor antibodies
Who is recommended for thyroid screening by the American thyroid association?
beginning at age 35 start screening every 5 years
What is parathyroid hormone?
secreted in parathyroid gland in response to hypocalcemia; when serum calcium levels are low PTH increases
What increases PTH?
hyperparathyroidism secondary to parathyroid cancer, hypocalcemia, chronic renal failure, malabsorption syndrome, vitamin D deficiency
What decreases PTH?
surgical ablation or parathyroid gland, Hypercalcemia, metastatic bone tumor, Hypercalcemia of malignancy, Vitamin D intoxication
What are the acute phase reactants helpful in evaluating autoimmune disease?
C-reactive protein and ESR
What are the factors that can interfere with ESR?
microcytosis or anemia increase, polycythemia decrease, abnormally shaped RBCs decrease
CRP
C-reactive protein
What give a mild C-reactive protein?
mild respiratory infection, pregnancy, post-exercise, obesity, depression
What can give a moderate C-reactive protein?
myocardial infarction, malignancy, autoimmune disease, rheumatoid arthritis
What can give a marked C-reactive protein?
overwhelming bacterial infection, severe trauma
autoimmune thyroiditis
hashimoto’s thyroiditis
What are the antibodies that have been found to be associated with autoimmune thyroid diseases?
thyroglobulin antibodies, thyroid peroxidase antibodies, thyrotropin TSH receptor antibodies
