Thyroid from Anterior
HPT AXIS
Produces is and Ty, stimulated Pituitary.
by
·
TSH
Ts is
biologically active.
Synthesised from Thyroglobulin precursor.
Ty abundantly produced, and is decodinised Ts.
·
is more to
80% of is comes from Ty, 20% is
synthesised by thyroid.
There is more free is than Ty.
Protein.
T/4 bind to proteins when in blood.
Thyroxine Binding
·
e.g.
Hypo:Free TSH (t feedback) Hyper:Free TSH (-feedback)
Free T3 Free T3
Free T4 Free T4
Hyperthyroidism
with mild
normocytic anaemia and
·
may come
neutropenia
females. Family History.
·
Onset 20-40 years, more common in
Causes: Grave's Disease (Autoimmunel
(more
-
common
Toxic Nodular Goitre
↑
-
Thyroiditis
-
lodine excess Grave's Disease
less
-
-
common
Adenoma
enlargement of thyroid / Heart.
-
Autoimmune Antibodies bind to
·
Symptoms: -
Lethargy TSH receptors in
Thyroid,
intolerance, notflushes, urticaria
Heat
overstimulating 3/4 synthesis.
-
-
30B
·
Continue drugs for 1.5years
before treatment,
Tremor, Myopathy, Hyperreflexia, Muscle wasting as 50% resolve.
-
Anxiety
-
Grave's
Weight loss, Diarrhoea, increased appetite/metabolism Eye symptoms:
-
-
Tachycardia, Palpitations, AF
·
Associated with smoking.
Shin Dedema
-
Double Vision
exofth almos
- -
-
Salman Erythema
-
lid retraction
hair loss -lid
lag
-
Osteoporosis -extraocular muscle swelling
-
Treatment:
GOITRE
·
Thionamide Drugs:
Carbimazole/Progylthiouracil (+B blocker to reduce symptoms).
·
Used to enter remission or
prepare for other treatment.
lead to monitor infection risk.
·
can neutropenia so
·Radioiodine
Therapy:radioactive iodine pill, iodine taken up by thyroid and radiation
destroys it.
·
Used as first-line, or after Thionamide if disease doesn'tresolve.
·
become
most hypo. post-treatment, can affectfertility, must self-isolate after.
Thyroidectomy:risk ofhoarse voice due to Recurrent for life.
·
Laryngealn. damage, needs L.
Thyroxine