Hypothyroidism

Question 1

A 65-year-old lady , presented with long standing goitre, malaise & chronic fatigue. FBC & full biochemical profile reviewed as part of her assessment & showed low T3 & T4, high TSH along with macrocytic anaemia.

Q1. What’s the most clinical diagnosis ?

Answer 1

1ry hypothyroidism

Question 2

Q4. Describe the physiological regulation of thyroid hormones.

Answer 2

Hypothalamus – > TRH – > + pituitary to release TSH – > + thyroid to release T3, T4
-ve feed back from T3T4 on pituitary

Question 2

Q2. What’s the type anaemia in this patient?

Answer 2

Macrocytic anemia

Question 3

Q3. What’re the causes of macrocytic anaemia?

Answer 3

Due to hypothyroidism
As thyroid hormones are important for proliferation of precursor cells in bone marrow and for erythropoietin producttion also
Also pt may have malnutrition.

Question 4

Q5. What are differences between T3 &T4?

Answer 4

Trioiodotyrosine – more active less ptn binding capacity
Tetraiodotyrosin – Less active more ptn binding capacity

Question 4

Q6. Talk about synthesis of T3 & T4.

Answer 4

. lodide ions enter the thyroid follicular cell by active pumping
. lodide is converted to iodine by TOP
. lodine combines with tyrosine forming: monoiodotyrosine (MIT) and diiodotyrosine (DIT)
. MIT + DIT = T3 (tri iodotyrosine)
. DIT + DIT = T4 (tetra iodotyrosine)

Question 5

Q7. What are the clinical features of hypothyroidism?

Answer 5

Low mood
CVS – Bradycardia
GIT– constipation and low appetite
Irregular menistuation.
Coarse dry skin

Question 6

Q8. Mention 3 causes of hypothyroidism.

Answer 6

Primary hypothyroidism – > post surgery, iatrogenic or radiation
Also autoimmune like in Hashimoto’s
Could be nutritional or ideopathic
2ry due problems of pituitary gland or hypothalamus failure

Question 7

Q9. If hypothyroidism is 2ry to hypopituitarism, how TFT could differ?

Answer 7

TFT become low

Question 8

Q11. She was put on medical therapy; she is not compliant to treatment. Which teams should be involved in management?

Answer 8

Endocrinologist, GP and also family member

Question 9

Q12. What are the problems associated with emergency surgery in patient with hypothyroidism?

Answer 9

Peri-op anemia
Risk of ischemic heart dis.
Intra-op bradycardia, hypotension, hypothermia ( cause coagulopathy)
Post-op – > myxedema coma and confusion.

Question 9

Q13. How to improve the patient’s compliance to thyroid replacement therapy?

Answer 9

Discussion with pt
Communication with her GP and family
Medical follow up and simple regimen
(L-troxyin)