1. Thyroid Diseases
Medical Perspective

2. Clinical Anatomy of Thyroid

3. Aspects That Will Be Addressed
Hyperthyroidism
Hypothyroidism
Thyroiditis

4. Hyperthyroidism

5. THYROID GLAND DISORDERS
THYROID GLAND REGULATION
“negative Feed-back” axis
Hypothalamus
(TRH positive effect)
Pituitary gland
(TSH, positive effect)
Thyroid gland
T3 & T4
(negative effect)

6. THYROID GLAND DISORDERS
THYROTOXICOSIS:
is defined as the state of thyroid hormone excesss
HYPERTHYROIDISM:
is the result of excessive thyroid gland function

7. Hyperthyroidism Symptoms
Hyperactivity/ irritability/ dysphoria
Heat intolerance and sweating
Palpitations
Fatigue and weakness
Weight loss with increase of appetite
Diarrhoea
Polyuria
Oligomenorrhoea, loss of libido

8. Hyperthyroidism Signs
Tachycardia (AF)
Tremor
Goiter
Warm moist skin
Proximal muscle weakness
Lid retraction or lag
Gynecomastia

9. Causes of Hyperthyroidism
Most common causes
Graves disease
Toxic multinodular goiter
Autonomously functioning nodule
Rarer causes
Thyroiditis or other causes of destruction
Thyrotoxicosis factitia
Iodine excess (Jod-Basedow phenomenon)
Struma ovarii
Secondary causes (TSH or ßHCG)

10. Graves Disease Autoimmune disorder
Abs directed against TSH receptor with intrinsic activity. Thyroid and fibroblasts
Responsible for 60-80% of Thyrotoxicosis
More common in women

11. Graves Disease Eye Signs
- no signs or symptoms
– only signs (lid retraction or lag) no symptoms
– soft tissue involvement (peri-orbital oedema)
– proptosis (>22 mm)(Hertl’s test)
– extra ocular muscle involvement (diplopia)
– corneal involvement (keratitis)
– sight loss (compression of the optic nerve)

12. Graves Disease Other Manifestations
Pretibial mixoedema
Thyroid acropachy
Onycholysis
Thyroid enlargement with a bruit frequently audible over the thyroid

13. Graves' Disease Goiter Hyperthyroidism Exophthalmos Localized myxedema
Thyroid acropachy
Thyroid stimulating immunoglobulins

14. Clinical Characteristics of Goiter in Graves’ Disease
Diffuse increase in thyroid gland size
Soft to slightly firm
Non-nodular
Bruit and/or thrill
Mobile
Non-tender
Without prominent adenopathy

15. Lid Lag in Thyrotoxicosis
Normal Lid Lag

16. Clinical Characteristics of Exophthalmos
Proptosis
Corneal Damage
Periorbital edema
Chemosis
Conjunctival injection
Extraocular muscle impairment
Optic neuropathy

17. Thyroid Ophthalmopathy
Proptosis
Lid lag

18. Ophthalmopathy in Graves
Occular muscle palsy
Laka Laka Laka

19. Ophthalmopathy in Graves
Periorbital edema and chemosis

20. Clinical Differentiation of Lid Retraction from Proptosis
sclera
seen above iris :
Observing position of lower lid (sclera seen below iris = proptosis, lid intersects iris = lid retraction)
Normal position
of eyelids
Proptosis
Lid retraction

21. Diagnosis of Graves Disease
TSH , free T4 
Thyroid auto antibodies
Nuclear thyroid scintigraphy (I123, Te99)

22. I 123 or TC 99m Normal v/s Graves
Graves Disease
I 123 or TC 99m Normal v/s Graves

23. Clinical Characteristics of Localized Myxedema
Raised surface
Thick, leathery consistency
Nodularity, sometimes
Sharply demarcated margins
Prominent hair follicles
Usually over pretibial area
Non-tender

24. Graves’ Disease - Localized Myxedema
Margins sharply
demarcated
Nodularity
Thickened skin
Margins sharply
demarcated

25. Diffuse Graves Thyroid
MNG and Graves
Huge Toxic MNG
Diffuse Graves Thyroid

26. Treatment of Graves Disease
Reduce thyroid hormone production or reduce the amount of thyroid tissue
Antithyroid drugs: propyl-thiouracil, carbimazole
Radioiodine
Subtotal thyroidectomy – relapse after antithyroid therapy, pregnancy, young people?
Smptomatic treatment
Propranolol

27. How long to give ATD ?
Reduction of thyroid hormones takes 2-8 weeks
Check TSH and FT4 every 4 to 6 weeks
In Graves, many go into remission after months
In such pts ATD may be discontinued and followed up
40% experience recurrence in 1 yr. Re treat for 3 yrs.
Treatment is not life long. Graves seldom needs surgery
MNG and Toxic Adenoma will not get cured by ATD.
For them ATD is not the best. Treat with RAI.

28. Radio Active Iodine (RAI Rx.)
I123 is used for Nuclear Scintigraphy (Dx.)
I131 is given for RAI Rx. (6 to 8 milliCuries)
Goal is to make the patient hypothyroid
No effects such as Thyroid Ca or other malignancies
Never given for children and pregnant/ lactating women
Not recommended with patients of severe Ophthalmopathy
Not advisable in chronic smokers

29. Radio Active Iodine (RAI Rx.)
In women who are not pregnant
In cases of Toxic MNG and TSA
Graves disease not remitting with ATD
RAI Rx is the best treatment of hyperthyroidism in adults
The effect is less rapid than ATD or Thyroidectomy
It is effective, safe, and does not require hospitalization.
Given orally as a single dose in a capsule or liquid form.
Very few adverse effects as no other tissue absorbs RAI

30. Preoperative Preparation
ATD to reduce hyper function before surgery
βeta blockers to titrate pulse rate to 80/min
SSKI 1 to 2 drops bid for 14 days
This will reduce thyroid blood flow
And there by reduce per operative bleeding
Recurrent laryngeal nerve damage
Hypo parathyroidism are complications

31. Thyrotoxicosis Factitia
Excessive intake of Thyroxine causing thyrotoxicosis
Patients usually deny – it is willful ingestion
This primarily psychiatric disorder
May lead to wrong diagnosis and wrong treatment
They are clinically thyrotoxic without eye signs of Graves
High doses of Thyroxine lead to TSH suppression
This causes shrinkage of the thyroid
Stop Thyroxine and give symptom relief drugs

32. Hypothyroidism

33. Hypothyroidism
Hypothyroidism is present when the thyroid gland is producing little or no thyroid hormones. Thus slowing things down....
Hyperthyroidism is present when the thyroid gland is producing little or no thyroid hormones. This slows the body down. People of any age can develop hypothyroidism. However, women age 60 and over are most prone to this disorder.

34. Hypothyroidism Symptoms
Tiredness and weakness
Dry skin
Feeling cold
Hair loss
Difficulty in concentrating and poor memory
Constipation
Weight gain with poor appetite
Hoarse voice
Menorrhagia, later oligo and amenorrhoea
Paresthesias
Impaired hearing

35. Hypothyroidism Signs Dry skin, cool extremities
Puffy face, hands and feet
Delayed tendon reflex relaxation
Carpal tunnel syndrome
Bradycardia
Diffuse alopecia
Serous cavity effusions

36. Hypothyroid Face
Notice the apathetic facies, bilateral ptosis, and absent eyebrows

37. Faces of Clinical Hypothyroidism

38. Causes of Hypothyroidism
Autoimmune hypothyroidism (Hashimoto’s, atrophic thyroiditis)
Iatrogenic (I123treatment, thyroidectomy, external irradiation of the neck)
Drugs: iodine excess, lithium, antithyroid drugs, etc
Iodine deficiency
Infiltrative disorders of the thyroid: amyloidosis, sarcoidosis,haemochromatosis, scleroderma

39. Lab Investigations of Hypothyroidism
TSH , free T4 
Ultrasound of thyroid – little value
Thyroid scintigraphy – little value
Anti thyroid antibodies – anti-TPO
S-CK , s-Chol , s-Trigliseride 
Normochromic or macrocytic anemia
ECG: Bradycardia with small QRS complexes

40. Treatment of Hypothyroidism
Levothyroxine
If no residual thyroid function 1.5 μg/kg/day
Patients under age 60, without cardiac disease can be started on 50 – 100 μg/day. Dose adjusted according to TSH levels
In elderly especially those with CAD the starting dose should be much less (12.5 – 25 μg/day)

41. Thyroiditis

42. Thyromegaly

43. Thyroiditis
Acute: rare and due to suppurative infection of the thyroid
Sub acute: also termed de Quervains thyroiditis/ granulomatous thyroiditis – mostly viral origin
Chronic thyroiditis: mostly autoimmune (Hashimoto’s)

44. Acute Thyroiditis Bacterial – Staph, Strep
Fungal – Aspergillus, Candida, Histoplasma, Pneumocystis
Radiation thyroiditis
Amiodarone (acute/ sub acute)
Painful thyroid, ESR usually elevated, thyroid function normal

45. Sub Acute Thyroiditis
Viral (granulomatous) – Mumps, coxsackie, influenza, adeno and echoviruses
Mostly affects middle aged women, Three phases, painful enlarged thyroid, usually complete resolution
Rx: NSAIDS and glucocorticoids if necessary

46. Sub Acute Thyroiditis (cont)
Silent thyroiditis
No tenderness of thyroid
Occur mostly 3 – 6 months after pregnancy
3 phases: hyperhyporesolution, last 12 to 20 weeks
ESR normal, TPO Abs present
Usually no treatment necessary

47. Clinical Course of Sub Acute Thyroiditis

48. Chronic Thyroiditis Hashimoto’s Autoimmune
Initially goiter later very little thyroid tissue
Rarely associated with pain
Insidious onset and progression
Most common cause of hypothyroidism
TPO abs present (90 – 95%)

49. Chronic Thyroiditis Reidel’s Rare Middle aged women Insidious painless
Symptoms due to compression
Dense fibrosis develop
Usually no thyroid function impairment

50. Thyroiditis
The most common form of thyroiditis is Hashimoto thyroiditis, this is also the most common cause of long term hypothyroidism
The outcome of all other types of thyroiditis is good with eventual return to normal thyroid function