HYPOTHYROIDISM

1. HYPOTHYROIDISM

2. HYPOTHYROIDISM Etiology • Primary: Hashimoto thyroiditis, radio active iodine therapy for graves’ disease, subtotal thyroidectomy, subacute thyroiditis, iodide deficiency • Secondary : Hypopituitarism due to pituitary adenoma • Tertiary :Hypothalamic disfunction (rare)

3. HYPOTHYROIDISM Clinical finding • Incidence : Various causes depending geographic & enviromental factors • Hashimoto thyroiditis the most common cause of hypothyroidism • Newborn infants (Cretinism) • Fatigue, coldness, weight gain, constipation, menstrual irregularities, muscle cramps

4. HYPOTHYROIDISM • Physical findings: Cool, rough n dry skin, puffy face and hands, hoarse voice, slow reflexes Cardiovascular sign: bradycardia, diminished CO, low voltage QRS, cardiac enlargement Pulmonary function: Respiratory failure Intestinal paralysis slowed , chronic constipation, ileus Renal function: decresed GFR, renal impairement Haematology : anemia, CNS symptoms: fatigue, inability to concentrate

5. THYROID Pituitary- thyroid relationships in primary hypothyroidism TRH Hypothalamus Dopamine Somatostatin Pituitary TSH Tissues T3, T4

7. Complication • Myxedema coma end stage of untreated hypothyroidism, cause radiotherapy in Graves’ Disease • Myxedema & Heart disease  CAD • Hypothyroidism Neuropsychiatricdisease  depression, confuse, paranoid, manic

8. Treatment Hypothyroidism • Levothyroxine (T4), not liothyronine (T3) because rapid absorption, short half life, transient effect. Dosage : 1 x in the morning to avoid insomnia 0.05 mg-0.2 mg/d • Mixedema coma ICU, intubation & mechanical ventilation, Treat infection, heart failure, IV drips with caution, levothyroxin IV

9. EXAMPLES OF THYROID DISEASES 1° Hypothyroidism Hyperthyroidism www.hsc.missouri.edu/~daveg/thyroid/thy_dis.html

10. Thyroiditis

11. Definition • Thyroiditis  heterogenous group of inflamatory disorders the thyroid gland • Etiologies range from autoimmune to infectious origins • Clinical course  Acute, subacute, or chronic. Can be euthyroid, transient phase thyrotoxicosis and / or hypothyroidism. Painless or painfull

12. Classification of thyroiditis I. Autoimmune thyroiditis Chronic autoimune thyroiditis Hashimoto’s thyroiditis Atrophic thyroiditis Focal thyroiditis Juvenile thyroiditis Silent thyroiditis / Postpartum thyroiditis II. Subacute thyroiditis III. Acute suppurative thyroiditis IV. Riedel’s thyroiditis

13. Hystologic classification Chronic lymphocytic Subacute lymphocytic Granulomatous Microbial inflamatory Invasive fibrosis Synonims Chronic lymphocytic thyroiditis, Hashimoto’s thyroiditis Subacut lymphocytic thyroiditis, Postpartum thyroiditis, Sporadic painless thyroiditis Subacut granulomatous thyroiditis De Quervains thyroiditis Suppurative thyroiditis Acute thyroiditis Riedel’s struma Riedel’s thyroiditis Classification of thyroiditis

14. Terminology for Thyroiditis. Type Synonim Hashimoto’s thyroiditis Chronic lymphocytic thyroiditis Chronic autoimmune thyroiditis Lymphadenoid goiter Painless postpartum thyroiditis Postpartum thyroiditis Subacute lymphocytic thyroiditis Painless sporadic thyroiditis Silent sporadic thyroiditis Subacute lymphocytic thyroiditis Painful subacute thyroiditis Subacute thyroiditis de Quervain’s thyroiditis Giant-cell thyroiditis Subacute granulomatous thyroiditis Pseudogranulomatous thyroiditis

15. Terminology for Thyroiditis. Type Synonim Suppurative thyroiditis Infectious thyroiditis Acute suppurative thyroiditis Pyogenic thyroiditis Bacterial thyroiditis Drug-induced thyroiditis - (amiodarone, lithium, interferon alfa, interleukin-2) Riedel’s thyroiditis Fibrous thyroiditis

16. Hashimoto’s thyroiditis(Chronic thyroiditis) Hakaru Hashimoto (1912)  4 patients chronic disorder of the thyroid diffuse lymphocytic infiltration, fibrosis, parenchymal atrophy, and eosinophilic change in some acinar cells Dr Hakaru Hashimoto

17. Hashimoto’s thyroiditis Hashimoto thyroiditis is the most common cause of hypothyroidism & goiter in theUnited States Statosky J et al. Am Acad of Family physicians 2000;61:1054

18. Hashimoto’s thyroiditis Etiology & pathogenesis HT is immunologic disorder which lymphocytes become sensitized to thyroidal antigens and autoantibodies are performed. Thyroid antibodies in HT are: 1. Thyroglobulin antibody (Tg Ab) 2. Thyroid peroxidase antibody (TPO Ab)-AMA 3. TSH Receptor blocking antibody (TSH- R Ab block)

19. Clinical Manifestation Hashimoto’s Thyroiditis Symptom & Signs HT usually presents with goiter , euthyroid or mild hypothyroidism. Sex distribution : F/M 4:1 Painless & patients may be anware of the goiter

23. Laboratory findings • T4 N/ low, TSH will be elevated. RAIU may be high, normal or low • Tg Ab & TPO Ab positif • Fine needle aspiration biopsy  large infiltration lymphocytes  Hurtle cells

24. Diagnostic procedures • Test of thyroid autoimmunity: TPOAb 95% + in Hashimoto thyroiditis & 90% Atrophic thyroiditis TgAb  less frequently + Diagnostic specificity of thyroid antibody tests is not absolute. • Test for thyroid function TSH, fT4 • RAIU: normal, low or high. • USG:diffusely reduced echogenecity. • FNAB not necessary,excep. rapidly enlarging goiter

25. Diagnosis of Hashimoto’s thyroiditis Diffuse goiter Anti microsomal (or TPO) antibody Anti-thyroglobulin antibody Positive Sign symptom of hypothyroidism Hashimoto’s thyroiditis Negative US Biopsy Positive *Simple goiter, adenomatous goiter etc Negative Other diseases*

26. Treatment Hashimotos thyroiditis

27. Treatment • Goiter small & asymptomatic not require therapy • Levo-thyroxine is given over hypothyroidism to supress TSH & decreased serum thyroid antibody. Levo-thyroxine in euthyroid, still controversial

28. Treatment • Corticosteroids : regression pain, reduction in size of the goiter, thyroid antibody , not recommended in benign disease. • Surgery indicated pain, cosmetic, or pressure symptoms after levothyroxine and corticosteroid therapy.

29. Riedel’s thyroiditis • Rare 1,06/100.000, middle age or elderly women • Etiology unknown (autoimmune process or primary fibrotic disorder) • Characterized  fibrosis replaces normal thyroid parenchyma,1/3 cases multifocal fibrosclerosis

30. Riedel’s thyroiditis • Thyroid fibrosis (stony hard,woody), painless, progressive anterior neck mass, • Generalized fibrosing (1/3 patients), pressure symptoms  laryngeal nerve paralysis or hypoparathyroidism (rare) • Usually euthyroidism, hypothyroidism (30%) • Laboratorium : non spesific • USG/CT-Scan inconclusive • Difinitive diagnosis  open Biopsy

31. Riedel’s thyroiditis • Treatment: Corticosteroids  medical treatment of choice Tamoxipen, methotrexate  inhibitor fibroblast proliferation ( early stages) Levothyroxine  hypothyroidism Surgical care  diagnosis, relieving tracheal compression • Mortality  asphyxia (6-10%), extrathyroidal fibrotic lesions may complicate the prognosis

32. Subacute thyroiditis • Cause unknown ( viral infection (?) preceded URT infection, coincidence viral disease (mumps, measles, Echo virus, adeno virus, epst. Barr virus, influenza) • Women : Men (3-5:1) • Onset: 20-60 yr • Summer

33. Subacute thyroiditis • Palpation thyroid: enlarged, asymetrical, nodul, firm, tender & painful. • Thyrotoxicosis during inflamatory phase  euthyroidism hypothyroidism euthyroidism (4th phases) • Laboratorium: ESR increase, leukocyt N/ increase, fT4,,TSH, RAIU • Recovery 4-6 months, spontaneous remitting

34. Changes in serum T4 & Radiactive iodine uptake in patients with subacute Thyroiditis 24-hour 131 I uptake % T4 ug/dL T4 40 20 30 15 10 20 5 10 131 I 0 0 Phase : Hyper Eu Hypo Eu Weeks: 1 4 11 - Woolf PD, Daly R :Am J Med 197;60:73

35. Laboratory findings during different phases of subacute thyroiditis Phase Thyrotoxicosis Hypothyroid Recovery T4 &/T3 Level High Low Normal TSH level Low Normal,or high High to normal RAIU value <5% Normal to high High to normal

36. Treatment Subacute thyroiditis • Symptomatic: Acetaminophen 4X 0,5g, NSAID or glucocorticoid (prednison 3 X 20 mg (7-10 days) • Betablockers symptoms of thyrotoxicosis • L-thyroxine 0.1-0.15 mg /daily  hypothyroid phase. Long-term L-thyroxine  permanent hypothyroidism (10%) • Antibioticsno value • Thyroidectomy  rarely

37. Clinical Differentiating of the Subtype Thyroiditis NECK PAIN N0 YES PRESENTING SYMPTOMS RAIU HYPERTHYROIDISM HYPOTHYROIDISM INCREASED DECREASED CHRONIC LYMPHOCYTIC THYROIDITIS RAIU MICROBIAL INFLAMMATORY THYROIDITIS SUBACUTE GRANULOMATOUS THYROIDITIS SUBACUT LYMPHOCYTIC THYROIDITIS GRAVES DISEASE Statosky J et al. Am Acad of Family physicians 2000;61:1054

38. Acute suppurative thyroiditis • Rare, serious, bacterial inflamatory disease, children, 20-40 yr, sex ratio 1:1 • Etiologi: Infectious: Staph. aureus, strep.pyogenes, strep. pneumonia, esch.coli, pseudomonas aeruginosa • Infection by hematogenous, direct trauma

39. Symptoms & signs • Neck pain, warm, tenderness, the neck unable to extend • Dysphagia, dysphonia, referred to ear, mandibula, lymphadenopathy • Systemic manifestation: fever, chills, tachycardia, malaise • Palpation: unilateral, erythematous

40. Acute suppurative thyroiditis • Thyroid function : Euthyroidism • Laboratorium :TPO antibodies absent, ESR high, PMN leukocytosis • 24-hour 123I uptake normal • FNA Biopsy: purulent material • Treatment: antibiotics or surgical drainage

41. Chronic-pyogenic thyroiditis • Etiology : Salmonella typhosa, syphilis, tuberculosis,echinococcus, actinomyces • Symptoms: Suppurative, non suppurative • Treatment: antibiotic, drainage

42. Thyroid nodules & Thyroid cancer

43. Thyroid nodules - prevalence • Thyroid nodules common, increase with age • 30-60% of thyroids have nodules at autopsy • Palpation: 5-20% ( > 1 cm ) • USG : 15-50% ( >2 mm )

44. Diagnostic approach • Fine Needle Aspiration (FNA) 10-20% risk of suspicious cytology, therefore  thyroid surgery 95% of histology will be benign, and surgery “unnecessary” • Isotop Scann(CT) rarely used for evaluation  80% of nodules are “cold” small cold nodules may be missed COLD nodules may be malignant • Ultrasonography (USG)

45. Diagnostic approach - ultrasound Identifies solid vs cystic nodules Identifies MNG May aid FNA Does not exclude malignancy

46. Diagnostic approach - other tests Calcitonin very high results diagnostic for MTC risk of borderline false positives not for routine use Thyroglobulin not helpful for exclusion of carcinoma: overlap with benign disease best for follow-up after thyroidectomy

47. Thyroid nodules & Thyroid cancer • In 95% of cases , thyroid cancer presents as a nodule or lump in the thyroid nodul thyroid. • Thyroid nodule extremely common, particularly women.Prevelance in USA 4% in adult population. F:M ratio 4:1. • Thyroid cancer rare. Incidence 0.004% per year

48. Diffrentiation benign & Malignant lesions • History : Family history of goiter suggests benign disease, endemic goiter • Physical characteristics: Benign: older age, woman, soft nodule, multi nodular goiter. Malignant: Children, young, male, solitary, firm nodule, vocal cord paralysis, firm lymph nodes, distant metastasis

49. Malignant thyroid Carcinoma • Papillary Carcinoma 75 % • Folliculare Carcinoma 16 % • Medullary Carcinoma 5 % • Anaplastic Carcinoma 3 % • Lymphoma 5 -10 %

50. Management of the solitary nodule