MCQs Thyroidt.docx

Q1. Which of the following is not true for Hashimoto thyroiditis? a) It is an autoimmune disease caused by CD4 cells with specificity to thyroid antigens b) commonly presents as hypothyroidism c) Surgery is required in almost all cases d) Hashimoto thyroiditis can progress to lymphoma of thyroid

Q 2. In which of the following conditions anti thyroid antibody may not be elevated? a) Hashimoto thyroiditis b) Grave's disease c) Multinodular goitre d) Lymphoma thyroid

Q3. Regarding thyroid and parathyroid neoplasms a. Follicular carcinoma of thyroid primarily spreads through lymphatics b. Parathyroid adenoma is the most likely cause of primary hyperparathyroidism c. Hürthle cell carcinoma is a variant of papillary carcinoma of the thyroid d Phaeochromocytoma is detected by measuring urinary 5-HIAA levels e. Superior laryngeal nerve supplies cricothyroid muscle

Q4. A complication of thyroidectomy which can be prevented by prophylaxis is a) Injury to recurrent laryngeal nerve b) Hypocalcemia c) Thyroid Storm d) Q5) What is the next step in investigating a 26 year old male with solitary thyroid nodule 1 cm in size? a) Radio Isotope scan b) Thyroid functions (T3,T4, TSH) c) USG guided FNAC d) Follow without investigations

Answers 1. c Hashimoto's thyroiditis is an autoimmune process that is thought to be initiated by the activation of CD4+T (helper) lymphocytes with specificity for thyroid antigens. Hypothyroidism is due to cytotoxic cells and autoantibodies. Primary treatment is Thyroxine and surgery is only indicated for cosmetic reasons . Hashimoto's thyroiditis more common in women (male: female ratio 1:10 to 20) between the ages of 30 and 50 years. Commony presents as moderately enlarged firm gland discovered on routine physical examn or the awareness of a painless anterior neck mass, although 20% of patients present with hypothyroidism, and 5% present with hyperthyroidism (hashitoxicosis) Chances of lymphoma are more in cases with hashimoto's thyroiditis.

2. d Antibodies include antithyroglobulin (anti-Tg), antimicrosomal or antithyroid peroxidase (anti-TPO) and thyroid-stimulating immunoglobulin (TSI). Anti-Tg and anti-TPO antibody levels they indicate the underlying disorder, usually an autoimmune thyroiditis. Approximately 80% of patients with Hashimoto's thyroiditis have elevated thyroid antibody levels, but levels may also be increased in patients with Graves' disease, multinodular goiter, and, occasionally, with thyroid neoplasms In Grave's disease antibodies are directed against (TRAbs) (thyroid hormone receptors) (TSI)

Notes Iodine Metabolism The average daily iodine requirement is 0.1 mg. Iodine is rapidly converted to iodide in stomach and jejunum. Iodide is actively transported into the thyroid follicles. Thyroid Hormone Synthesis involves four steps 1.Thyroid trapping of iodide 2. Oxidation of iodide into iodine and coupling with tyrosine to form monoiodotyrosine and diiodotyrosine. 3. Coupling to form T3 and T4 4.Hydrolisation of Thyroglobulin to release T3 and T4

In the euthyroid state, T4 is produced and released entirely by the thyroid gland, whereas only 20% of the total T3 is produced by the thyroid. Most of the T3 is produced by peripheral deiodination of T4 in the liver, muscles, kidney, and anterior pituitary, The thyroid gland is capable of autoregulation, which allows it to modify its function independent of TSH. As an adaptation to low iodide intake, the gland preferentially synthesizes T3 rather than T4, thereby increasing the efficiency of secreted hormone. In situations of iodine excess, iodide transport, peroxide generation, synthesis, and secretion of thyroid hormones are inhibited.

3.e 4. c Thyroid storm, a manifestation of severe thyrotoxicosis, is avoided by prophylactic treatment with propylthiouracil or methimazole prior to surgery. 5. B Although some or all of these tests may be required at some stage, the initial investigation would be thyroid function tests to look at whether the patient is hypothyroid or hyperthyroid. Low TSH means hyperthyroidism and is further evaluated with Radio isotope scan. It also suggests lower chance of malignancy High TSH suggests hypothyroidism most likely Hashimoto's thyroidits

MCQs : Thyroid By Wasim R. Issa1:56 PMMCQsLeave a Comment

1- what is the vertical extension of the thyroid in relation to the vertebrae ?

a- C4 to T1 b- C5 to T1 c- C6 to T1 d- C3 to T1

answer : B

2- the thyroid develops from ?

a- ectoderm b- mesoderm c- dorsal pharyngeal gut endoderm d- ventral pharyngeal gut endoderm

answer : D

3- screening method for medullary carcinoma of thyroid ?

a- serum calcitonin b- serum calcium c- serum ALP d- serum acid phosphatase

answer : A

4- medullary carcinoma of thyroid arises from ?

a- parafollicular cells b- cells lining the acini c- capsule of thyroid d- stroma of the gland

answer : A

5- which of the following is/are used in the management of thyroid malignancy?

a- Iodine 131 b- Iodine 125 c- Technitium 99 d- Phosphorus 32 e- strontium

answer is A

6- characteristic eye sign in dysthyroid status ?

a- exopthalmos b- ptosis c- optic neuropathy d- myopathy

answer : A

7- hurthle cells are seen in ?

a- hashimoto's thyroiditis b- follicular cell carcinoma c- hurthle cell thyroid adenoma d- all the above

answer is D

8- C cells populate which part of the lateral lobe of the thyroid ?

a- upper one-third of the lateral lobe of thyroid b- middle one-third of the lateral lobe of thyroid c- lower one-third of the lateral lobe of the thyroid d- distributed equally all over the lateral lobe of the thyroid

answer :B

9- pick out the correct statements .

a- the external laryngeal nerve runs close to the superior thyroid artery . b- the recurrent laryngeal nerve runs close to the inferior thyroid artery .

c- the external laryngeal nerve runs close to the inferior thyroid artery . d- the recurrent laryngeal nerve runs close to the superior thyroid artery .

answer : both A and B are correct . ( so the surgeon has to be very careful while ligating those arteries, while performing thyroidectomy ).

10- treatment of medullary carcinoma of the thyroid with lymphnode metastasis?

a- subtotal thyroidectomy + radioiodine b- subtotal thyroidectomy + radiotherapy c- neartotal thyroidectomy + radioiodine d- neartotal thyroidectomy + radiotherapy e- total thyroidectomy + radiotherapy

answer : E

11- what is near total thyroidectomy ?

a- right lobectomy + isthmusectomy b- left lobectomy + isthmusectomy c- bilateral lobectomy with isthmusectomy d- right lobectomy + isthmusectomy + left half lobectomy e- right and left lobectomy

answer : D

12- papillary carcinoma of thyroid with bone metastasis is treated by?

a- subtotal thyroidectomy + radioiodine b- subtotal thyroidectomy + radiotherapy

c- near total thyroidectomy + radioiodine d- near total thyroidectomy + radiotherapy e- total thyroidectomy + chemotherapy

answer : C and D

13- most common cause of thyroiditis is ?

a- hashimoto's thyroiditis b- reidl's thyroiditis c- subacute thyroiditis d- viral thyroiditis

answer : A

14- thyroglossal cyst may occasionally give rise to which carcinoma ?

a- papillary b- anaplastic c- medullary d- follicular

answer : A

15- a post-thyroidectomy patient develops signs and symptoms of tetany. The management is ?

a- I.V calcium gluconate b- Bicarbonate c- Calcitonin

d- Vitamin D

Answer : A

16- hypoparathyroidism following thyroid surgery occurs with in ?

a- 24 hours b- 2-5 days c- 7-14 days d- 2-3 weeks

Answer : B

17- a patient undergoes thyroid surgery following which he develops perioral tingling . his blood calcium is 8.9 meq/l. next step in the management is ?

a- vitamin D orally b- oral calcium and vitamin D c- intravenous calcium gluconate and serial monitoring d- wait for calcium to decrease to less than 7 meq/l before taking further action

answer : B

18- a patient after undergoing thyroid surgery presents with perioral paraesthesia . serum calcium level is 7 mg/dl . what will be the best management ?

a- oral vitamin D3 b- oral vitamin D3 and calcium c- I.V calcium gluconate d- Oral calcium

Answer : D

19- which of the following is not a complication of total thyroidectomy ?

a- bleeding b- airway obstruction c- hoarseness d- hypercalcemia

answer : D

20- in post operative room after thyroid surgery , patient developed sudden respiratory distress , dressing was removed and it was found to be slightly blood stained and wound was bulging . what will be the first thing to be done ?

a- tracheostomy b- cricothyroidectomy c- laryngoscopy and intubation d- remove the stitch and take the patient to O.T

answer : D

21- a patient presents with neck swelling and respiratory distress few hours after a thyroidectomy surgery. Next management would be ?

a- open immediately b- tracheostomy c- wait and watch d- oxygen by mask

answer : A

22- after thyroidectomy patient developed stridor within 2 hours. All are likely causes of stridor except ?

a- hypocalcemia b- recurrent laryngeal nerve palsy c- laryngomalacia d- wound hematoma

answer : A . hypocalcemia due to hypoparathyroidism after thyroid surgey normall results with in 2-5 days .

23- papillary carcinoma of the thyroid ( PCT ) patients are ?

a- euthyroid b- hypothyroid c- hyperthyroid d- T3 thyrotoxicosis

Answer : A

24- HURTHLE cell carcinomas are derived from which cells ?

a- follicular cells b- para follicular cells c- oxyphilic cells d- lymphocytes

answer : C

25- the malignancy which is common on long standing goiter ?

a- PCT b- MCT c- FCT d- Anaplastic

Answer : C . Follicular carcinoma of the thyroid .

26- least malignant thyroid cancer ?

a- papillary b- medullary c- anaplastic d- follicular

answer : a ( mean the more differentiation ) and the commonest tumor is it .

27- which of the following gene defects is associated with development of the medullary carcinoma of the thyroid ?

a- RET proto oncogene ( on chromosm 10 ) b- FAP gene c- RB gene d- BRCA 1 gene

Answer :A RET proto gene : associated with medullary thyroid carcinoma, hirschsprung's disease and pheochromocytoma and rearrangement of RET gene leads to papillary thyroid carcinoma

28- psammoma bodies are seen in all of the following conditions except ?

a- serous cystadenoma of ovary b- papillary carcinoma of thyroid c- meningioma d- mucinous cystadenoma of ovary

answer : D

29- all of the following are early life threatening complications of thyroid operation except ?

a- tracheomalacia and collapse of larynx b- wound hematoma with compression of the trachea c- hypocalcemia d- thyroid storm

answer : C

30- in pregnancy ?

a- thiouracil is contraindicated b- surgery is contraindicated c- radioiodine is contraindicated d- none

answer: C

31- lateral aberrant thyroid refers to ?

a- congenital thyroid abnormality b- metastatic foci from primary in the thyroid c- struma ovarii d- lingual thyroid

answer : B

32- a patient presented with headache and flushing . he has a family history of his relative having died of a thyroid tumor. The investigation that would be required for this patient will be ?

a- chest x-ray b- measurement of 5-HIAA c- measurement of catecholamine d- intravenous pyelography

answer : C . measurement of catecholamines . headache and flushing suggest symptoms of adrenal tumor and a history of thyroid tumor in the relative suggest the MEN syndrome type 2a or 2b . so the adrenal tumor is probably pheochromocytoma and so catecholamines have to be measured .

33- cancer that develops after irradiation ?

a- PCT b- MCT

c- FCT d- Anaplastic

Answer : A

34- mutated p53 gene is formed in most of ?

a- anaplastic carcinomas b- PCT c- MCT d- FCT

Answer : A

35- treatment of choice for medullary carcinoma of thyroid is ?

a- total thyroidectomy b- partial thyroidectomy c- iodine 131 ablation d- hemithyroidectomy

answer : A