Download MBBS Hypothyroidism Lecture PPT

Download MBBS (Bachelor of Medicine and Bachelor of Surgery) Latest Hypothyroidism Lecture PPT


HYPOTHYROID.
Thyroid gland.

?Thyroid is a small gland found in the middle of the

lower neck.

?Thyroid works with pituitary gland which

produces thyroid stimulating hormone(TSH).

?TSH stimulate the thyroid gland to produce the

thyroid hormone,T3 and T4.

Thyroxine Hormone

vIodine, a trace mineral, is essential for the

synthesis of thyroid hormone..

vThyroxine(T4) and triiodothyronine (T3).

v20 % of T3 derived directly from thyroid gland

and 80 % by conversion from T4.

vThyroid hormone regulate metabolism in every

cell of the body and play a role in virtually all

physiological function.
Regulating thyroid hormone.

o When the amount of thyroid hormone in the blood

drops, the pituitary gland secretes a hormone called

thyroid stimulating hormone(TSH).

o TSH then stimulate the thyroid gland to increase its

uptake of iodine from the blood, so that more

thyroxin(T4) can be synthesized.

o When necessary, thyroid is then converted to the

metabolically active triodothyroxine(T3), a process that

involves removing one iodine atom from T4.
TSH: THYROID STIMULATING

HORMONE.

?ELEVATED TSH.
?> 5mU/L

?LOW TSH.

HYPERTHYROIDISM ?< 0.5mU/L.
.

TEST

FROM

TO

UNITS

TSH

0.25

5.00

mU/L

FT4

9.0

25.0

pmol/L

FT3

3.5

7.8

pmol/L


THYROID TEST

? TSH--NORMAL RANGE--0.25--5.0 mU/L.

? Symptomatic primary hypothyroidism > 20
? Mild symptomatic hypothyroidism 10 to 20
? Primary hyperthyroidism < 0.05.
? Thyroxine(T4)
? Triiodothyronine(T3)
? Free T3
? Free T4
Labs.

Hyperthyroidism

? FT4
? TSH

Hypothyroidism

? FT4
? TSH.
Labs.

TSH

HIGH-TSH

LOW

FT4- LOW

HYPOTHYROIDISM

FT4 AND FT3-LOW

HIGH-FT4 AND

CENTRAL

FT3

HYPOTHYROIDISM.

HYPOTHYROID

THYROTOXICOSIS.
WHEN TO HAVE THYROID

FUNCTION TEST.

? Swelling in the neck
? Abnormal menstrual cycle
? Fertility problem
? High cholesterol
? Weight gain
? Puffiness of Face, dry skin, hair loss
? Fatigue, lethargy, Anemia etc..


THYROID REGULATION.
Physiological actions of Thyroxin

hormones.

? Potentiates brain development.
? Increases heart rate.
? Increases cardiac output.
? Increases ventilation rate.
? Thickens of endometrium in female.
Metabolic effects of Thyroid

hormones.

vThe hormone exerts action on every cell on

the body.

vCalorigenic effect or thermogenesis is the

major effect of throid hormone.

vThis thermogenic effect is mediated by

uncoupling of oxidative phosphorylation.
vBasal metabolic rate (BMR) is increased.

vThyroxine increases cellular metabolism.

vEarliest effect of T4 is stimulation of RNA

synthesis and consequent increase in protein
vsynthesis Higher concentration of T3 causes

protein catabolism and negative nitrogen

balance.

vLoss of body weight is a prominent feature of

hyperthyroidism.
vGluconeogenesis and carbohydrate oxidation

are increased.

vGlucose tolerance test shows rapid absorption.
vFatty acid metabolism is increased.

vCholesterol degradation is increased and
hence cholesterol level in blood is decreased,
which is another hallmark of hyperthyroidism.


CAUSE OF HYPOTHYROIDISM.
hypothyroidism.



? Hypothyroidism is a thyroid problem caused

by an underactive thyroid gland that produces

insufficient amount of thyroid hormones.

? Hypothyroidism is seen in both sexes, but is

more common in women.

? In pregnancy new born is at risk of cretinism.
? Cold intolerance
? Constipation.
? Lethargy
? Dry and course skin and hair
? Facial puffiness
? Anemia
? Impaired memory
? Confusion
? Dementia
? Low speech and motor activity.



Complications.

? Untreated condition, patient is at risk for?
? Diabetes.
? High blood pressure.
? Arthritis.
? Depression.
? Recurrent infection.
? Migraine.
Classification of hypothyroidism.

Due to failure

Due to

Due to failure

of the thyroid

hypopituitarism.

of

gland itself.

hypothalmus.

PRIMARY.

TERTIARY.

SECONDARY.
Hypothyroidism(GOITRE).

? Excess stimulation by TSH due to decreased

level of circulating thyroid hormones, leads to

enlargement of thyroid gland.

? Reason:
? 1. Iodine deficiency.
? 2.certain antithyroid drugs.
? 3.Hashimoto's thyroiditis.

This post was last modified on 30 November 2021