Quiz 2: Inflammatory Flashcards
What are the four autoimmune lab tests?
erythrocyte sedimentation rate, c-reactive protein, antinuclear antibody, rhematoid factor
What is ESR used for?
non-specific test used as a marker for inflammation, infection, neoplasm, and tissue necrosis or infarction
Is ESR constant?
No, frequent false elevations
Normally, erythrocytes are (x) charged and therefore (x) eachother
- negatively charged
- repel
In cases of inflammation or infection, the body releases X, including x and x.
the body releases acute phase reactants, including fibrinogen and immunoglobulins (antibodies)
Acute phase reactants are x charged
positively charged
When acute phase reactants are released, the environment around RBC becomes more x which leads to x
neutral which leads to “stacking of RBCs”
Stacking of RBCs is called
Rouleaux formation
How is ESR performed?
blood is aspirated into a sedimentation tube (westergren tube), blood separates into plasma and RBCs over 60 minutes, the amount of “settling” is measured
Normal ESR value
0-20 mm/h
A higher ESR level corresponds to:
more stacking of RBCs = more antibodies or inflammation
Factors that can increase ESR (RBC)
microcytosis or anemia (fewer or smaller RBCs present–falls farther)
Factors that decrease ESR (RBC)
More RBCs (polycythemia), abnormally shaped RBCs such as sickle cell (don’t “fall” well)
ESR is elevated in:
inflammatory states, autoimmune disease, obesity, malignancy, age, infection (serious)
C-reactive protein is an
acute phase reactant
Function of c-reactive protein
recognize and respond to inflammatory mediators and target damaged tissue for clearance and also activate complement system
A CRP level above x is likely to be significant
10 mg/dL
A CRP level above x is a fairly sensitive and specific indicator that there is an overwhelming bacterial infection present
50 mg/dL
C-reactive protein >10 (mild)
mild respiratory infection, pregnancy, post-exercise, obesity, depression
Moderate C-reactive protein level
MI, malignancy, autoimmune disease, RA
Marked C-reactive protein level >50
overwhelming bacterial infection, severe trauma
ANA =
antinuclear antibody
ANA test measures
the presence of autoantibodies towards proteins that are specific to the nucleic acids or complexes infolved with DNA or RNA
ANA is important in the diagnosis of
systemic lupus erythematosus (SLE)
What is SLE?
a chronic inflammatory disease that affects multiple joints and organs and is caused by an autoimmune process
What is not impacted in the butterfly rash?
Nasolabial folds
What is impacted in progressive systemic sclerosis (scleroderma)?
skin thickening and hardening, digital ulcers
Sjogren Syndrome manifests with:
diminished lacrimal and salivary gland function, dry eyes, dry mouth, vaginal dryness, rhinitis and sinusitis, lymphoma
Antinuclear antibodies are identified through:
indirect immunofluorescence
How is the ANA test performed?
the sample is diluted through a set of serial dilutions and the highest dilution at which the antinuclear antibodies are detected is reported as the result
Negative ANA test:
1:40 dilution
Positive ANA test:
1:160
What are the four patterns of the ANA test?
peripheral, diffuse, speckled, nucleolar
Diffuse (homogenous) ANA test
SLE
Peripheral or rim ANA test
SLE
Nucleolar ANA test
SLE or scleroderma
Speckled ANA test
SLE, scleroderma, others
What is rheumatoid arthritis?
autoimmune disease that manifests with joint stiffness, pain, swelling, and eventual deformity of MCP and PIP joints of hands
What is the primary lab to diagnose rhematoid arthritis?
rheumatoid factor
Rheumatoid arthritis impacts the synovial joints x and x
symmetrically and bilaterally
TSH normal value
0.5-5.0 uIU/mL
Where is the thyroid gland located?
anteriorly int he neck from the fifth cervical vertebrae to the first thoracic vertebrae
The two lateral lobes of the thyroid gland are connected by the
medial isthmus
Control of the thyroid gland is regulated by the
hypothalamus and pituitary gland
What is TRH?
Thyrotropin–releasing hormone
Where is TRH synthesized?
hypothalamus
Where is TRH transported to?
pituitary gland
What does TRH stimulate?
secretion of TSH
What does TSH bind to?
receptors on the thyroid gland
What does TSH stimulate the release of?
Thyroid hormones (T3 and T4)
T3 stands for
triiodothyronine
T4 stands for
thyroxine
Big place you see thyroid affect:
cardiovascular and metabolism
Which is more metabolically active: T3, T4
T3
T3 and T4 increase
myocardial contractility and heart rate, mental alertness, ventilator drive, bone turnover, GI motility
TSH stands for
thyroid stimulating hormone
What is the most frequent cause of hypothyroidism?
primary hypothyroidism (defect in thyroid gland)
What is secondary hypothyroidism?
decreased secretion of TSH from pituitary or decreased TRH from hypothalamus
What deficiency can cause hypothyroidism?
iodine
What disorders cause hypothyroidism?
autoimmune thyroiditis (Hashimoto’s thyroiditis), iodine deficiency, thyroidectomy, radiation to neck, treatment for hyperthyroidism
What is the most common cause of primary hypothyroidism?
Autoimmune thyroiditis (Hashimoto’s thyroiditis)
Causes of secondary hypothyroidism?
pituitary tumor, post-partum pituitary necrosis
Tertiary hypothyroidism:
hypothalamus source
Symptoms of hypothyroidism:
fatigue, dull mentation, dry skin, weight gain, bradycardia, constipation, cold intolerance
In hypothyroidism would you expect a high or low TSH value?
High
How do we differentiate thyroid disease?
Measure TSH and Free T4
What percent of thyroid production is T4?
90%
What percent of thyroid production is T3?
10%
Is T3 or T4 more metabolically active?
T3
Is T4 bound or un-bound?
Nearly all T4 is bound to protein
What is free T4?
unbound, free metabolically active form of T4
Is T4 or free T4 a better reflection of thyroid function?
Free T4
What percent of T3 is bound to proteins?
70%
In hypothyroid states, the serum TSH is elevated and in those conditions, the thyroid prefers and “chooses” to release
T3 so the T3 level remains constant, even in the face of disease
So as hypothyroidism progesses: TSH increases…
then free T4 decreases…and the last to holdout is T3
What will test results look like in hypothyroidism resultant from disorder of hypothalamus or pituitary gland
TSH is decreased and Free T4 is decreased
Test results for subclinical hypothyroidism?
high normal or mildly elevated TSH with a normal free T4
Test results for primary hypothyroidism:
High TSH, low Free T4
Hypothyroidism AKA
thyrotoxicosis
Most common form of hyperthyroidism is called
Grave’s Disease
What is Grave’s disease caused by:
autoantibodies (TSH receptor antibody or TRAb) that bind and activate TSH receptors of the thyroid gland
Are TSH levels high or low in hyperthyroidism?
low
What is unusual about someone with Grave’s Disease’ eyes?
Exophthalmos
Aside from Grave’s disease what are other causes of hyperthyroidism?
hyperplasia of thyroid cells whose function is not regulated by TSH (toxic adenoma, toxic multinodular goiter), iodine rich medications
Symptoms of hyperthyroidism:
anxiety, tremors, palpitations, weight loss, hyperdefacation
All patients with primary hyperthyroidism have a suppressed:
TSH
Overt hyerthyroidism levels:
low TSH, high free T4 and T3
Sublclinical hyperthyroidism:
TSH is low, but serum T3, Free T3, and Free T4 are all normal
