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Graves Disease
Karan J. Walston
Biology 003: Dr. Zigmond
March 21, 2002
1

thyroid gland controls metabolism
through the secretion of T4 and T3
hormones

one of the largest glands in the
endocrine system
2
T3 & T4 Function:

secretion of t3 & t4
by thyroid is
controlled by
endocrine feedback
system involving
pituitary gland &
the hypothalamus
in the brain
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Epidemiology
 discovered in Bath, England
1835 by Robert Graves
 affects approximately 3 out of
1000 people
 more prevalent in women & in
families with a history of the
disorder
4

graves’ disease can occur at any
age, but is unusual before puberty

most common in older adults

7:1 ratio predominance in women
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What is Graves’ Disease ?

autoimmune disease and the
leading cause of hyperthyroidism

mainly affects the thyroid gland

can also affect the eyes and skin
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
What is an autoimmune
disease?

What initiates these
autoimmune reactions?
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autoimmune response occurs
when the immune system incorrectly
identifies parts of healthy cells in the
body as “invaders” and produces
antibodies to attack the cells
8

autoimmune disease with
hyperthyroidism is when the goiter or
thyroid gland are
immunologically mediated

results from the production of autoantibodies directed against the TSH
(thyroid stimulating hormone) receptors
on the thyroid follicular cells or thyroid
gland
 antibodies attack these cells
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2 types of auto-antibodies:

TSI (thyroid simulating immunoglobins or
TSH –receptor antibodies (TRAb) mimic
the action of TSH, thereby inducing the
hypersecretion of the thyroid hormone

TGI (thyroid growth stimulating
immunoglobulins) initiates the growth of
thyroid cells or the thyroid gland
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Autoimmune Reactions Triggered by:
 viruses or bacteria in genetically
predisposed individuals
 certain strains of E.coli or Yersina
entercolitica possess cell
membrane TSH receptors

emotional stress plays a big factor
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Other Names for the Disease are:

most common is




Hyperthyroidism, not to be confused with
Hypothyroidism
toxic goiter
parry disease
basedow’s disease
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Graves’ Disease Symptoms:




nervousness
irritability
unexplained weight
loss
increased appetite

diarrhea

excessive sweating

heat intolerance

thyroid enlargement

rapid pulse
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Other Symptoms:

about 50 % of patients
have exophthalmos

raised plaque like itchy
skin on the legs

rapid pulse is can result in
cardiac failure=thyroid
storm
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Diagnosis:

physical exam

thyroid scan showing diffusely
increase uptake of radioactive
isotope (131I) to test thyroid
function

blood test for T4 & T3 – abnormally
high
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Treatments:

radioactive iodine

since 1939 treatment for
hyperthyroidism has been radioactive
iodine isotope (131I)

antithyroid drugs

thyroidectomy
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Problems with Treatments:

with radioactive iodine

correct dosage

underactive thyroid

hormone pill

radioactive materials
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Anti-thyroid Drugs:
2 types:
Propylthiouracil
Thyroxine
 low success rate
 can cause leukemia
 high relapse rate
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Surgery-Thyroidectomy



removal of thyroid gland
possible complications of voice box
replacement hormone pill
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Genetic Factors:

genetics may play a role but
inconclusive

there is an association between the
disease and the genes HLA or
(human leucocyte antigen) B8,
-DRw3, -Bw36
 50% concordance found between
identical twins
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Hypothyroidism:




underactivity of thyroid gland
risk factors
symptoms
treatment
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Recap:




symptoms
endocrinologist
blood test
radioactive iodine
uptake






treatment
follow-up
look for
reoccurring
symptoms
hypothyroidism
research
www.thyroid.org
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Questions:




Can you have children with graves’
disease?
How dangerous is radioactive
iodine and can it be past to fetus?
Does radioactive iodine isotope
cause cancer?
What are some other
manifestations related to this
disease?
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References:
Klein, I,Becker DV, Levey Gs. Treatment of
Hyperthyroid Disease: Ann Intern Med. 1994 Aug
15; 121 14:28-18
Merck Medical Manual of Diagnosis and
Therapy: Whitehouse Station, N.J. Merck & Co., inc
2000
http://www.nlm.nih.gov/medlineplus/ency
http:/www.thyroid.org/publications
http://www.sci.lib.uci.edu/hsg/Medical.html
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