Hypothyroidism, its clinical features and management

1. Presented by: ANISH DHAKAL
10th
May, 2019
HYPOTHYROIDISM

2. Relevant Anatomy
 Weight: 20 – 40 gram
 Two lobes connected by isthmus
 Functioning unit: Lobule
 Each lobule has 24-40 follicles, which
has colloid
 In colloid, thyroglobulin is stored
 Each lobule is supplied by single
arteriole

3. Arterial Supply
Thyroid arteries (main blood supply)
 Superior thyroid artery
 Inferior thyroid artery
Branches of tracheal and esophageal arteries
Venous Drainage
Superior Thyroid Vein
Middle Thyroid Vein
Inferior Thyroid Vein
 All drain to Internal Jugular Vein

4.  Lymphatic Drainage
 Some lymph channel drain directly to Deep
Cervical Nodes
 Others drain principally to
 Central compartment- ‘Delphian’ and
paratracheal nodes
 Nodes of superior and inferior thyroid vein (Level
VI) and from there to Deep Cervical(level II, III, IV,
V)
 Mediastinal group(VII)
 Nerves
 Recurrent Laryngeal Nerve
 External Branch of Superior Laryngeal Nerve

5. Regulation of hormone secretion

7. Thyroid hormone biosynthesis and secretion
 Iodide uptake
 Iodide organification (MIT and DIT)
(thyroperoxidase)
 Coupling of MIT and DIT (thyronines)
 Storage in the colloid (thyroid follicles)
 Endocytosis of colloid droplets
 Proteolysis and hormone secretion

8. Important investigations
 Serum TSH (T3 & T4 if abnormal)
 Thyroid autoantibodies
 TSH receptor antibodies (TRAb)---Graves
disease
 Anti-thyroid peroxidase autoantibodies---
Hashimoto’s thyroiditis
 FNAC of palpable discrete swellings

9. Results of thyroid function tests in
normal and pathological states

10. Hypothyroidism

11. Clinical features of Hypothyroidism
Symptoms:
 Tiredness
 Somnolence
 Lethargy
 Cold intolerance
 Dry skin, dry hair
 Weight gain
 Constipation
 Menorrhagia
 Carpal tunnel syndrome

13. Clinical features of Hypothyroidism
Signs
 Bradycardia
 Cold extremities
 Facial features
 Purplish lips
 Periorbital oedema/myxoedema
 Periorbital puffiness
 Hoarse voice
 Bradykinesis, slow movements
 Delayed relaxation phase of ankle jerks

14. Myxoedema
 Clinical syndrome where sign and symptoms of
hypothyroidism is accentuated
 Characterized by typical facial appearance
 supraclavicular puffiness
 malar flush
 and yellow tinge to the skin

16. Management
 Thyroxine replacement
 Start with low dose—50mcg/day for 3 weeks
 Increasing thereafter to 100 mcg/day for further 3 weeks
 Finally maintenance dose of 100-150 mcg/day
 Patients feel better within 2-3 weeks
 TSH level as reference and should be reviewed in
in 1-2 years

17. In Ischemic Heart Disease
 Should be used cautiously
 Complications of thyroxine-exacerbation
of MI, Infarction, sudden death
 Start with very low dose and increase
very slowly

18. In pregnancy
 In pregnancy, higher dose is required 25-
50 microgram
 Reason- increased metabolism of
thyroxine by placenta and increased
serum thyroxine binding globulin during
pregnancy

19. Myxoedema coma
 Medical emergency(carries a high mortality rate)
 Altered mental state
 Hypothermia and a
 Precipitating medical condition, for example cardiac failure or infection
 Thyroid replacement, either bolus of 500 mg of T4 or 10 μg of
T3 (IV or orally) every 4–6 hours
 If the body temperature <30 degree Celsius the patient must be
warmed slowly

20. Contd…
 Other measures includes
 Intravenous broad-spectrum antibiotics
and hydrocortisone (in divided doses)
 Cautious use of IV fluid
 High flow oxygen

22. THANK YOU