Endocrinology Flashcards
1
Q
Neck swellings
A 56-year-old lady complains of an intermittent swelling under her jaw on the left side. The swelling increases in size and becomes painful when she eats.
A Anaplastic carcinoma of thyroid B Benign tumour of parotid (pleomorphic adenoma) C Branchial cyst D Papillary carcinoma of the thyroid E Pharyngeal pouch F Riedel's thyroiditis G Solitary thyroid nodule H Submandibular calculus I Thyroglossal cyst J Virchow's node
A
Submandibular calculus
This is a typical history of a submandibular stone. On eating, the salivary glands are stimulated to produce saliva. As there is a calculus present in the duct the gland swells because it is obstructed. This occurs most commonly in the submandibular gland. The stone may be palpable in the floor of the mouth.
2
Q
Neck swellings
A 70-year-old lady presents with a two month history of a swelling in the front of the neck. There has been a rapid increase in the size of the lump. She has become hoarse. On examination she is noted to have an audible wheeze and there is a large hard mass in the lower anterior part of the neck.
A Anaplastic carcinoma of thyroid B Benign tumour of parotid (pleomorphic adenoma) C Branchial cyst D Papillary carcinoma of the thyroid E Pharyngeal pouch F Riedel's thyroiditis G Solitary thyroid nodule H Submandibular calculus I Thyroglossal cyst J Virchow's node
A
Anaplastic carcinoma of thyroid
This is a very short history of two months. The rapid increase in size suggests malignancy. The other features which are compatible with this are the hoarse voice due to involvement of the recurrent laryngeal nerve.
The audible wheeze will also be due to pressure on the trachea and paralysis of the recurrent laryngeal nerve will also have effects on the vocal chord. The hard mass in the lower anterior part of the neck is suggestive of anaplastic carcinoma.
Riedel’s thyroiditis would also produce a hard, irregular swelling of the thyroid gland, but have a longer history.
3
Q
Neck swellings
A 60-year-old man presents with a 4 x 2 cm mass to the left of the midline in the lower neck. The mass is oval in shape with a smooth surface. It moves upwards on swallowing.
A Anaplastic carcinoma of thyroid B Benign tumour of parotid (pleomorphic adenoma) C Branchial cyst D Papillary carcinoma of the thyroid E Pharyngeal pouch F Riedel's thyroiditis G Solitary thyroid nodule H Submandibular calculus I Thyroglossal cyst J Virchow's node
A
Solitary thyroid nodule
This swelling is benign as is it oval and smooth in shape. It is obviously connected with the thyroid because it moves on swallowing.
It is not a thyroglossal cyst because it is to the left of the midline. It is not a branchial cyst because it moves on swallowing.
4
Q
Neck swellings
A 14-year-old girl presents with a swelling on the left side of the neck. It is painless but has been slowly increasing in size. On examination there is a smooth 5 x 5 cm swelling arising from beneath the anterior aspect of the upper third of the sternomastoid muscle.
A Anaplastic carcinoma of thyroid B Benign tumour of parotid (pleomorphic adenoma) C Branchial cyst D Papillary carcinoma of the thyroid E Pharyngeal pouch F Riedel's thyroiditis G Solitary thyroid nodule H Submandibular calculus I Thyroglossal cyst J Virchow's node
A
Branchial cyst
This is a branchial cyst, which is usually presents in young people. It may not be apparent until an infection develops; and the classical position is at the anterior aspect of the upper third of the sternomastoid muscle.
5
Q
Neck swellings
A 65-year-old man presents with difficulty with swallowing, weight loss and vomiting. On examination he is cachexic with a firm swelling in the left supraclavicular fossa.
A Anaplastic carcinoma of thyroid B Benign tumour of parotid (pleomorphic adenoma) C Branchial cyst D Papillary carcinoma of the thyroid E Pharyngeal pouch F Riedel's thyroiditis G Solitary thyroid nodule H Submandibular calculus I Thyroglossal cyst J Virchow's node
A
Virchow’s node
The history is suggestive of gastric carcinoma at the cardia with secondaries in the supraclavicular nodes, that is, Virchow’s node. The dysphagia, weight loss and vomiting would be compatible with a pharyngeal pouch but this would produce a soft swelling of variable size in the left side of the neck.
6
Q
Causes of impotence
A 35-year-old male presents with a six month history of reduced libido and impotence. He is rarely aware of any erection and has lost interest in sex. He has been married for 10 years. He has been taking lansoprazole for gastro-oesophageal reflux disease for 18 months. His results show a testosterone of 6.8, a LH of 2.1 and FSH 3 with a prolactin of 1550.
Normal ranges:
Testosterone 10-30 nmol/L
LH 1-10 mu/L
FSH 1-10 mu/L
Prolactin 100-500 mu/L
A Addison’s disease B Haemochromatosis C Klinefelter’s syndrome D Non-functioning pituitary tumour E Primary gonadal failure F Prolactinoma G Psychological H Thyrotoxicosis I Vascular
A
Prolactinoma
Proalctinoma/microprolactinoma is suggested by the elevated prolactin concentration which is not caused by the drug therapy and the hypogonadotrophic hypogonadism (inappropriately normal LH/FSH - these should rise in the face of a low testosterone but remain in the normal range suggesting a pituitary abnormality).
Prolactinomas are rather unusual in men but do need to be considered.
7
Q
Causes of impotence
A 23-year-old male presents with a three month history of deteriorating impotence. He is aware of normal morning erections, has normal sex drive but is frequently unable to sustain erections with his newly acquired partner. This is putting a strain on his relationship. He confesses to having smoked the occasional cannabis joint but takes no regular medication. His results show a testosterone of 13.5, LH 3.2, FSH 2.5 and prolactin 335.
A Addison’s disease B Haemochromatosis C Klinefelter’s syndrome D Non-functioning pituitary tumour E Primary gonadal failure F Prolactinoma G Psychological H Thyrotoxicosis I Vascular
A
Psychological
Psychological impotence is the commonest cause of impotence and the history of normal erectile function with normal early morning erections and intermittent failure of erections.
Although cannabis may cause impotence the past history is not supportive. His results are entirely normal.
8
Q
Causes of impotence
A Addison’s disease B Drug induced C Haemochromatosis D Klinefelter’s syndrome E Non-functioning pituitary tumour F Primary gonadal failure G Prolactinoma H Psychological I Thyrotoxicosis J Vascular
A
Haemochromatosis
There are numerous drug induced causes of impotence.
In the first patient’s case, investigations are normal and therefore it would appear that the bendroflumethiazide is the most probable cause of his impotence.
Haemochromatosis, an autosomal recessive disorder associated with excess iron deposition, is classically associated with arthritis, diabetes and hypogonadotrophic hypogonadism. This is typically due to iron deposition within the pituitary. Primary hypogonadism may also occur.
The normal LH and FSH in the presence of low testosterone indicates hypogonadotrophic hypogonadism as they are inappropriately low for the low testosterone concentration.
9
Q
Interpreting thyroid function tests
Non-functioning pituitary tumour (NFPT).
A Free T4 12.1 nmol/L, TSH 7.9 mU/L
B Free T4 18.6 nmol/L, TSH 0.07
C Free T4 33 nmol/L, TSH 3.1 mU/L
D Free T4 55 nmol/L, TSH
A
Free T4 8.2 nmol/L, TSH 2.1 mU/L
A NFPT may be associated with hypopituitarism and secondary hypothyroidism with a low thyroxine (T4) plus normal or low thyroid-stimulating hormone (TSH). If the T4 is low yet the TSH normal then this would suggest that the TSH is abnormally low for the T4 suggesting that the pituitary hypothalamic axis is dysfunctional.
10
Q
Interpreting thyroid function tests
Subclinical hypothyroidism.
A Free T4 12.1 nmol/L, TSH 7.9 mU/L
B Free T4 18.6 nmol/L, TSH 0.07
C Free T4 33 nmol/L, TSH 3.1 mU/L
D Free T4 55 nmol/L, TSH
A
Free T4 12.1 nmol/L, TSH 7.9 mU/L
Subclinical hypothyroidism is associated with a normal T4 but elevated TSH. This suggests a developing thyroid failure. The raised TSH signals a reacting pituitary with the elevated TSH endeavouring to increase T4 secretion from the thyroid.
11
Q
Interpreting thyroid function tests
Subclinical hypothyroidism.
A Free T4 12.1 nmol/L, TSH 7.9 mU/L
B Free T4 18.6 nmol/L, TSH 0.07
C Free T4 33 nmol/L, TSH 3.1 mU/L
D Free T4 55 nmol/L, TSH
A
Free T4 18.6 nmol/L, TSH 0.07
The converse applies for subclinical hyperthyroidism where pituitary secretion is being inhibited by the excessive for the individual (although still in normal range) T4.
12
Q
10 year survival of thyroid cancer
A 25-year-old man found to have a 1 cm papillary thyroid cancer undergoes a total thyroidectomy. The disease is confined to the thyroid.
A 90%
A
> 90 %
Papillary thyroid cancer is the commonest type of thyroid cancer (50-60% of all thyroid cancers).
This form is commonest in young adults. Under the age of 40 years in males and 50 years in females the disease tends to have a very good prognosis. Overall the 10 year survival rate is approximately 80%, with the rate being 90-95% in the favourable group with disease confined to the thyroid.
13
Q
A 32-year-old woman undergoes a total thyroidectomy for a 1.5 cm medullary thyroid carcinoma confined to the thyroid.
A
50-60%
Medullary thyroid cancer is uncommon (6-8% of all thyroid cancers). Tumour growth is variable. Overall approximately 50% of patients will be alive at 10 years. Approximately 20% of medullary thyroid cancers are familial and are associated with the multiple endocrine neoplasia (MEN) syndromes.
14
Q
A 72-year-old man is found to have an anaplastic thyroid cancer on fine needle aspiration.
A
15
Q
A 45-year-old woman undergoes a total thyroidectomy for a follicular thyroid cancer. No metastases are found on staging.
A
50-60%
Follicular carcinoma can occur from young adulthood onwards (15-20% of all thyroid cancers). Follicular thyroid cancers tend to spread by the blood stream and may therefore present with metastases. Overall 60 % of patients will be alive at 10 years.
16
Q
During a thyroidectomy, ligation of the superior thyroid artery at its origin may be associated with damage to which of the following?
External laryngeal Glossopharyngeal (IX) Hypoglossal (XII) Internal laryngeal Recurrent laryngeal
A
External laryngeal
The external laryngeal nerve descends under cover of the sternothyroid and lies deep to the superior thyroid artery.
It pierces the inferior constrictor of the pharynx and enters the cricothyroid, supplying both of these muscles.
17
Q
Neck mass
A 4-year-old boy presents with a red tender swelling in the midline, which rises when he protrudes his tongue.
A Branchial cyst B Cystic hygroma C Dermoid cyst D Goitre E Haemangioma F Laryngocele G Sternomastoid tumour H Teratoma I Thyroglossal duct cyst
A
Thyroglossal duct cyst
The 4-year-old boy has a midline mass. The differential lies between thryoglossal cyst, goitre, dermoid cyst, teratoma or laryngocele. The clinical presentation suggests an infected thyroglossal cyst.
18
Q
Neck mass
A 2-day-old infant presents with large transilluminating mass in the right posterior triangle of the neck.
A Branchial cyst B Cystic hygroma C Dermoid cyst D Goitre E Haemangioma F Laryngocele G Sternomastoid tumour H Teratoma I Thyroglossal duct cyst
A
Cystic hygroma
The 2-day-old infant has a mass in the posterior triangle which transilluminates. A cystic hygroma is likely.
19
Q
Neck mass
A 2-week-old infant is noted to keep her head to the left. On examination she has a palpable lump in the left side of the neck.
A Branchial cyst B Cystic hygroma C Dermoid cyst D Goitre E Haemangioma F Laryngocele G Sternomastoid tumour H Teratoma I Thyroglossal duct cyst
A
Sternomastoid tumour
The 2-week-old infant has a firm mass in the body of sternocleidomastoid associated with decreased head movement to the contralateral side, a sternomastoid tumour. This responds to stretching exercises.
20
Q
Neck masses
A
Neck masses may be congenital or acquired.
Congenital masses may be in the midline, in the anterior triangle, posterior triangle, body or sternocleidomastoid or anywhere.
Masses in the anterior triangle represent branchial cleft cysts.
Haemangiomas can occur anywhere, but are easily identified by their soft, spongy red characteristics.
21
Q
Surgical glycaemic control
A 36-year-old female with gestational diabetes who is receiving four times daily insulin is to undergo elective caesarian section. Her HbA1c is 6.8%.
A Add glibenclamide B Add long acting subcutaneous insulin C Add metformin D Add short acting subcutaneous insulin E Omit oral hypoglycaemic agent F Continue with current therapy unchanged G Omit current agents H Stop current regimen; start insulin sliding scale
A
Start insulin sliding scale
When not eating and drinking within 4 hours of surgery and independent of the complexity or length of the procedure in both type 1 and type 2 patients, sliding scale insulin with dextrose infusion (same cannula with volumetric pump) is generally required.
22
Q
Surgical glycaemic control
A 36-year-old female with gestational diabetes who is receiving four times daily insulin is to undergo elective caesarian section. Her HbA1c is 6.8%.
A Add glibenclamide B Add long acting subcutaneous insulin C Add metformin D Add short acting subcutaneous insulin E Omit oral hypoglycaemic agent F Continue with current therapy unchanged G Omit current agents H Stop current regimen; start insulin sliding scale
A
Continue with current therapy unchanged
With type 1 patients for minor procedures, they can have their usual morning dose of insulin (plus breakfast) for an afternoon list but this is omitted (as they are starved) for a morning list. Hypoglycaemia is avoided with appropriate dextrose infusion and regular BM checks. (If they have a midday dose of insulin this must be omitted).
23
Q
Surgical glycaemic control
A 21-year-old female with type 1 diabetes being treated with twice daily insulin is admitted for suction termination of pregnancy on an afternoon operating list.
A Add glibenclamide B Add long acting subcutaneous insulin C Add metformin D Add short acting subcutaneous insulin E Omit oral hypoglycaemic agent F Continue with current therapy unchanged G Omit current agents H Stop current regimen; start insulin sliding scale
A
Omit oral hypoglycaemic agent
These cases illustrate the importance of appropriate management of diabetic patients undergoing surgery.
For ‘minor’ procedures (defined as eating and drinking within 4 hours of surgery) if patients are taking oral hypoglycaemic agents the drugs are omitted prior to surgery and the procedure performed with close supervision of glycaemic control.
Caesarian sections may be delayed for a variety of reasons and therefore a sliding scale would be appropriate.
24
Q
A 32-year-old lady who is heavily pregnant presents to her general practitioner as she is concerned about a swelling which has appeared in the anterior part of her neck. She has no previous medical history of note.
On examination, the GP finds a non-tender, smooth, firm and symmetrically enlarged thyroid gland.
Examination of the patient’s thyroid status suggests that she is euthyroid. There are no palpable lymph nodes.
Which one of the following is the most likely diagnosis?
Multinodular goitre Simple goitre Thyroglossal cyst Thyroid malignancy Thyroid nodule
A
Simple goitre
A simple goitre diffusely affects the whole gland without causing nodularity.
It is caused by a compensatory hypertrophy and hyperplasia of the gland.
A common cause is a physiological goitre due to increased demands for thyroid hormone which can occur in pregnancy.
Other causes include
Dietary iodine deficiency
Treated Graves’ disease and
Hereditary defects in thyroid metabolism.
A simple diffuse goitre can progress to form a multinodular goitre. If this were the case, the goitre would be expected to be asymmetrically enlarged.
25
Post surgery for a thyroid tumour, a woman develops a hoarse voice.
Her surgeon explains to her that the reason for this is a vocal cord paralysis caused by accidental damage to the recurrent laryngeal nerve.
This has most likely been damaged during ligation of which blood vessel running next to it?
```
Inferior thyroid artery
Inferior thyroid vein
Superior thyroid artery
Superior thyroid vein
Thyroid ima artery
```
Inferior thyroid artery
The recurrent laryngeal artery is related to the inferior thyroid artery.
The recurrent laryngeal nerve runs in the groove between the trachea and the oesophagus. It enters the larynx deep to the inferior constrictor muscle.
The inferior thyroid artery is a branch of the thyrocervical trunk.
The external laryngeal nerve runs near the superior thyroid artery but is less commonly damaged. Damage to this nerve will generally only lead to a slight hoarseness.
The superior thyroid artery is a branch of the external carotid artery.
26
A 79-year-old gentleman is admitted with a history of nocturia, frequency, poor flow, hesitancy and terminal dribbling; and retention due to benign prostatic hypertrophy is diagnosed.
Insertion of a catheter drains 2000 ml.
Whilst awaiting urological review, a check U and E has shown that his sodium level has increased from 138 mmol/l on admission to 155 mmol/l (137-144) and his potassium is unchanged at 3.7 mmol/l (3.5-4.9).
He has been normotensive throughout his admission.
What is the likely cause of this finding?
```
Cardiac failure
Cirrhosis
Cushing's syndrome
Nephrotic syndrome
Post-obstruction diuresis
```
Post obstruction diuresis
The likely diagnosis is post-obstruction diuresis during which, in addition to hypernatraemia, there is also an increased urinary loss of sodium (urinary sodium more than 30 mmol/l).
In Cushing's syndrome the hypernatraemia is usually associated with hypokalaemia and hypertension and thus is unlikely in this scenario.
The remaining options are all causes of hyponatraemia.
27
A 31-year-old woman is seen in the clinic complaining of weight loss and palpitations.
On examination she has a tremor and an irregularly irregular pulse. She has a smooth goitre which has a bruit and there is exophthalmos. Thyroid function tests are requested.
Which of the following combinations represents the clinical condition?
```
T4 ↑; T3 ↑; TSH ↓
T4 ↑; T3 N; TSH ↓
T4 ↑; T3 ↑; TSH ↑
T4 ↓; T3 ↓; TSH ↑
T4 ↓; T3 ↓; TSH ↓
```
T4 ↑; T3 ↑; TSH ↓
The patient has Graves' disease and in addition to the T4 ↑; T3 ↑; TSH ↓ pattern will have anti-TSH receptor antibodies.
Other features of Graves' include:
```
Heat intolerance
Diarrhoea
Poor concentration
Alopecia
Warm flushed skin
Hyperreflexia and
Pretibial myxoedema
Additional eye signs include:
```
```
Lid retraction
Lid lag
Proptosis and
Exophthalmos
The second profile (T4 ↑; T3 N; TSH ↓) is compatible with a toxic nodular goitre and the third (T4 ↑; T3 ↑; TSH ↑) with pituitary hyperthyroidism. Neither of these will have antithyroid antibodies or exophthalmos.
```
The fourth profile (T4 ↓; T3 ↓; TSH ↑) is primary hypothyroidism.
The fifth profile (T4 ↓; T3 ↓; TSH ↓) represents secondary hypothyroidism.
28
```
A 48-year-old woman is seen in the colorectal clinic with alteration in bowel habit. She also notes a definite weight gain over the past year.
Examination of the abdomen is unremarkable.
What is the likely diagnosis?
(Please select 1 option)
Graves' disease
Hyperparathyroidism
Hypothyroidism
Pituitary hyperthyroidism
Toxic nodular goitre
```
Hypothyroidism
Weight gain and constipation are important features of hypothyroidism, whilst others include
```
Bradycardia
Cold intolerance
Hyporeflexia
Myopathy
Weakness
Coarse skin
Poor memory
Hoarse voice.
It is essential to examine carefully the neck of patients with constipation, especially if there are no other GI symptoms, and also request a thyroid function test.
```
29
A 34-year-old woman who has been on long term steroid immunosuppression following a renal transplant 20 years previously is seen in the clinic.
She is obese with a moon face and has abdominal striae. Routine biochemical tests are requested.
Which of the following is a likely finding given the history?
```
Hypercalcaemia
Hyperkalaemia
Hypoglycaemia
Hyponatraemia
Metabolic alkalosis
```
Metabolic alkalosis
Cushing's syndrome is associated with
```
Hyperglycaemia
Hypernatraemia
Hypokalaemia
Metabolic alkalosis
Hypertension.
```
30
A 45-year-old man is admitted as an emergency with renal colic.
He has a past medical history which includes renal calculi and acute pancreatitis and is being investigated for bone pain.
Biochemical investigations are requested.
Which of the following is a likely finding?
```
Deficiency of vitamin D3
Hypercalcaemia
Hyperphosphataemia
Hypocalcaeima
Hypocalciuria
```
Hypercalcaemia
The clinical history suggests primary hyperparathyroidism which is characterised by the combination of high calcium and low phosphate levels as well as hypercalciuria.
The diagnosis is confirmed by measuring parathyroid hormone (PTH) which will be markedly elevated.
Vitamin D3 levels should not be affected in this condition.
31
A 56-year-old woman with a longstanding history of chronic renal failure who has been on haemodialysis for five years complains of bone pain affecting her left hand.
An x ray is performed and is reported as demonstrating osteitis fibrosa cystica.
What is the clinical diagnosis?
```
Osteoarthritis
Osteoporosis
Paget’s disease
Primary hyperparathyroidism
Secondary hyperparathyroidism
```
Secondary hyperparathyroidism
Secondary or renal hyperparathyroidism is a common finding in chronic renal failure.
It is associated with hypocalcaemia and hyperphosphataemia and in most cases it may be managed with phosphate binders and calcium supplementation. If surgery is required then a subtotal parathyroidectomy is the procedure of choice.
Osteitis fibrosa cystica is a radiological feature of severe hyperparathyroidism (primary or secondary), subperiosteal erosion being a more common feature.
32
```
Thyroid disease
A Graves' disease
B Multinodular goitre
C Thyroiditis
D Thyroxine overdose
E Toxic thyroid adenoma
In the following cases, select the most likely diagnosis:
Normal ranges
T4 9-22
T3 3.5-5.5
TSH 0.35-5
```
A 56-year-old housewife presents with weight loss, sweating and a goitre. Clinical examination reveals a heart rate of 100 bpm, a moderate goitre with no retrosternal extension. Examination of the eyes reveals lid retraction and lid lag. Free T4 is 36.7 pmol/l and TSH
Toxic thyroid adenoma
The 56-year-old housewife has thyrotoxicosis with increased focal uptake on uptake scintigraphy indicating a toxic adenoma.
33
```
Thyroid disease
A Graves' disease
B Multinodular goitre
C Thyroiditis
D Thyroxine overdose
E Toxic thyroid adenoma
In the following cases, select the most likely diagnosis:
Normal ranges
T4 9-22
T3 3.5-5.5
TSH 0.35-5
```
A 35-year-old man who works as a taxi driver presents with a three month history of palpitations, sweating and a goitre. Clinical examination reveals a heart rate of 60 bpm, a small painless goitre and no evidence of hyperthyroidism. His tests show free T4 8 pmol/l and TSH of 16 mlU/l (NR 0.3-4.5). Thyroid peroxidase antibodies are positive.
Thyroiditis
The 35-year-old male has hypothyroidism most likely due to a Hashimoto's thyroiditis.
34
```
Thyroid disease
A Graves' disease
B Multinodular goitre
C Thyroiditis
D Thyroxine overdose
E Toxic thyroid adenoma
In the following cases, select the most likely diagnosis:
Normal ranges
T4 9-22
T3 3.5-5.5
TSH 0.35-5
```
A 17-year-old female who works in a chemist presents with a six month history of sweating excessively when exercising in the gym. Clinical examination reveals a heart rate of 120 bpm, lid retraction and lid lag. No goitre is palpable. Free T4 is 28 pmol/l and TSH
Thyroxine overdose
The 17-year-old female has thyrotoxicosis and this is due to excessive intake of exogenous thyroxine as there is no uptake of radio-iodine indicating that the gland is suppressed.
35
```
Calcium disorders
A Bisophosphonate treatment
B Calcitonin
C Exploration and parathyroidectomy
D No action required
E Rehydration with 0.9% saline
```
A 55-year-old man presents with recurrent renal stones. Investigation has revealed a calcium of 2.70 mmol/L corrected for albumin. His PTH is 10 pmol/L. 24 hour urinary excretion of calcium is 12 mmol/24 hours. Ultrasound of the neck did not detect any sign of a parathyroid adenoma. SestaMIBI scan is inconclusive.
Normal ranges:
Serum corrected calcium 2.2 - 2.6 mmol/L
PTH 3 - 7 pmol/L
Urine Calcium 2.5 - 7.5 mmol/24h
Exploration and parathyroidectomy
This man has hypercalcaemia and high PTH with hypercalciuria indicating primary hyperPTH. The most appropriate treatment would be surgery.
36
A 60-year-old female is referred to your clinic for an incidental finding of corrected hypercalcaemia: 2.8 mmol/L. Her PTH is 7.1 pmol. 24 hour urinary excretion of calcium is 1.7 mmol/24 hours. SestaMIBI scan of the neck has detected a possible adenoma posterior to the left lower pole of the thyroid.
No action required
This woman has mild hypercalcaemia but a normal PTH (this would be inappropriately normal and still could reflect hyperPTH) but her urine calcium is low and this would suggest familial hypocalciuric hypercalcaemia - no treatment is required.
37
```
Calcium disorders
A Bisophosphonate treatment
B Calcitonin
C Exploration and parathyroidectomy
D No action required
E Rehydration with 0.9% saline
```
A 70-year-old female on the orthopaedic ward who has been admitted today with a right neck of femur fracture. She is confused and her calcium result is 2.9 mmol/L corrected.
Normal ranges:
Serum corrected calcium 2.2 - 2.6 mmol/L
PTH 3 - 7 pmol/L
Urine Calcium 2.5 - 7.5 mmol/24h
Rehydration with 0.9% saline
| This woman needs rehydration first and then investigation to establish the cause of the hypercalcaemia.
38
```
Calcium disorders
A Bisophosphonate treatment
B Calcitonin
C Exploration and parathyroidectomy
D No action required
E Rehydration with 0.9% saline
```
You have just admitted a 75-year-old lady with a painful vertebral crush fracture of the 10th thoracic vertebra. She has a calcium of 2.53 mmol/L corrected.
Bisophosphonate treatment
This woman has a normal calcium concentration but also what appears to be a osteoporotic fracture, for which bisphosphonates would be most appropriate.
39
Diabetes
A IV insulin with 5% dextrose sliding scale
B No action required
C Omit diabetes medication on morning of procedure
D SC insulin alone
E Stop oral hypoglycaemics 48 hours before procedure
In the following cases, select the most appropriate management.
A 25-year-old male with diabetes presents on your intake with a perianal abscess. He takes short acting insulin 8 units with meals and long acting insulin 10 units at night. His current blood glucose is 6 mmol/L. You plan to drain this abscess under GA in the morning.
Omit diabetes medication on morning of procedure
The minor operative procedure for the young man with good glycaemic control can be performed with omission of his morning insulin and then continuous review of BMs plus IV dextrose in the immediate post-operative period until he is able to eat normally.
40
Diabetes
A IV insulin with 5% dextrose sliding scale
B No action required
C Omit diabetes medication on morning of procedure
D SC insulin alone
E Stop oral hypoglycaemics 48 hours before procedure
A 75-year-old man with diabetes is admitted for investigations of claudication. He takes metformin 850 mg BD. His renal function is normal. In general his capillary blood glucoses range between 7-11 mmol/L at home. Your plan is to perform an angiogram before a femoral-popliteal bypass.
Omit diabetes medication on morning of procedure
For the man who is to have an angiogram it is important to omit the morning metformin and ensure adequate hydration prior to the procedure. There is the potential for contrast nephropathy. If this occurs high levels of metformin may cause lactic acidosis. This is rare in patients with normal renal function. Renal function should be monitored post-procedure before metformin is restarted. In patients with known renal impairment metformin should be stopped 48 hours before the procedure. Metformin has length of action of 24-36 hours.
41
Diabetes
A IV insulin with 5% dextrose sliding scale
B No action required
C Omit diabetes medication on morning of procedure
D SC insulin alone
E Stop oral hypoglycaemics 48 hours before procedure
A 55-year-old female with diabetes is admitted for wide local excision of a breast lump. She takes gliclazide 80 mg OD. Her blood glucose shows a level of 6.1 mmol/L.
Omit diabetes medication on morning of procedure
This woman requires just stopping the medication pre-operatively with frequent monitoring of BMs.
42
Diabetes
A IV insulin with 5% dextrose sliding scale
B No action required
C Omit diabetes medication on morning of procedure
D SC insulin alone
E Stop oral hypoglycaemics 48 hours before procedure
A 55-year-old male who has had diabetes mellitus since the age of eight is being admitted for an anterior resection of the colon in the morning. He takes insulin glargine 15 Units per day and actrapid insulin 6 units with each meal. His current capillary blood glucose is 13.7 mmol/L.
IV insulin with 5% dextrose sliding scale
This gentleman is to have a major procedure and requires conversion to sliding scale insulin.
43
```
Thyroid cancer
A Anaplastic carcinoma
B Follicular adenoma
C Follicular carcinoma
D Lymphoma
E Medullary thyroid carcinoma (MTC)
F Papillary carcinoma
```
For each patient described below, select the most likely single diagnosis from the list of options.
Each option may be used once, more than once or not at all.
A 16-year-old girl presents to the surgical outpatient department with a neck swelling. Clinical examination shows a 2.8 cm solid lump in the left thyroid lobe and two enlarged cervical lymph nodes lateral to the thyroid mass. Ultrasonography confirms the solid nature of the thyroid nodule. FNA biopsy of the thyroid nodule reveals malignant cells with vesicular appearance of nuclei. The nodule is cold on radio-isotope scanning.
Papillary carcinoma
The young girl has a thyroid cancer, most likely to be a papillary carcinoma as suggested by age alone
44
```
Thyroid cancer
A Anaplastic carcinoma
B Follicular adenoma
C Follicular carcinoma
D Lymphoma
E Medullary thyroid carcinoma (MTC)
F Papillary carcinoma
```
For each patient described below, select the most likely single diagnosis from the list of options.
Each option may be used once, more than once or not at all.
A 70-year-old man presents to the outpatients department with a rapidly enlarged thyroid swelling and hoarseness. Clinical examination shows a 2.8 cm solid lump in the left thyroid lobe and two enlarged cervical lymph nodes lateral to the thyroid mass. Ultrasonography confirms the solid nature of the thyroid nodule. FNA biopsy of the thyroid nodule reveals malignant cells with vesicular appearance of nuclei. The nodule is cold on radio-isotope scan.
Anaplastic carcinoma
This contrasts with the male who with local invasion and also the later age, would be more typical of an anaplastic lesion.
45
Which of the following is regarded as a physiological effect of thyroid hormones?
```
Decrease gluconeogenesis
Enhance insulin sensitivity
Reduce myocardial oxygen demand
Reduce nerve conduction
Reduce oxidation of fatty acids in tissues
```
Enhance insulin sensitivity
Thyroid hormones enhance:
- Insulin-dependent entry of glucose into cells
- Myocardial oxygen consumption
- Nerve conduction
- Gluconeogenesis and
- Oxidation of fatty acids.
46
A 52-year-old schoolteacher attends with weight loss and sweats. She is clinically thyrotoxic with a diffuse goitre.
Subsequent investigations show:
Free T4 40 pmol/l (9-23)
Free T3 9.8 nmol/l (3.5-6)
TSH 6.1 mU/l (0.5-5)
A repeat TFT is similar.
What is the most appropriate investigation for this patient?
FNA of thyroid gland
MRI scan pituitary gland
Radio-isotope uptake scan of thyroid gland
Repeat TFT checking for antibody interference
Thyroid auto antibodies
MRI scan
This patient is thyrotoxic; however, as the non-suppressed thyroid-stimulating hormone (TSH) suggests that this is due to excessive TSH production by the pituitary gland, the possibility of a thyrotroph adenoma must be pursued.
In primary hyperthyroidism the TSH should always be suppressed by negative feedback, which is not the case here.
TSH-omas are indeed very rare, but the giveaway would be the normal or elevated TSH with thyrotoxicosis.
47
A 49-year-old female two days post total thyroidectomy has developed tetany in both hands. Her corrected serum calcium is 1.90 mmol/l (2.2-2.6).
What is the most appropriate management for this patient?
```
Breathing into a brown paper bag
Intravenous calcium gluconate
Oral calcium supplements
Oral thyroxine
Surgical re-exploration of the neck and revascularisation of the parathyroids
```
Intravenous calcium gluconate
Complications following thyroidectomy include
Bleeding
Recurrent and superior laryngeal nerve injury
Infection
Hypoparathyroidism.
The most common complication of total thyroidectomy is hypocalcaemia secondary to hypoparathyroidism.
Parathyroid glands produce parathyroid hormone (PTH), which is intimately involved in the regulation of serum calcium. Inadequate production of PTH leads to hypocalcaemia. Hypoparathyroidism, and the resulting hypocalcaemia, may be permanent or transient.
Following thyroidectomy, especially total thyroidectomy, the serum calcium usually falls gradually and patients do not usually require supplementary medication before 24 hours.
Patients who have symptomatic hypocalcaemia in the early postoperative period, or whose calcium levels continue to fall, require treatment.
In the symptomatic patient, replace calcium with intravenous calcium gluconate.
48
A 58-year-old female four hours post total thyroidectomy has developed acute shortness of breath.
On examination the patient is visibly distressed and has stridor. Removing the dressings reveals a large haematoma deep to the wound.
Which of the following is the most appropriate immediate management?
```
Cricothyroidotomy
Immediate endotracheal intubation
Immediate removal of the skin clips and deep sutures at the bedside
Supplementary oxygen through a mask
Washout of haematoma in theatre
```
Immediate removal of the skin clips and deep sutures at the bedside
An unrecognised or rapidly expanding haematoma can cause airway compromise and asphyxiation.
The immediate management of stridor following thyroidectomy requires the immediate removal of the skin clips and sutures to relieve pressure on the trachea. Failure to take immediate action will result in tracheal occlusion and death. Delays in getting patients to theatre may result in an avoidable death.
Following the opening of the neck on the ward the patient should be transferred to the operating theatre for a thorough examination of the neck and meticulous control of bleeding before closing the neck wound.
49
A 50-year-old woman is admitted to the surgical ward for resection of a colorectal carcinoma. She has type 2 diabetes and her current glycaemic control is good on 5 mg glibenclamide daily.
Which of the following is the most appropriate pre-operative management plan for this patient's glycaemic control?
Continue glibenclamide at current dose
Give one bolus injection of insulin plus potassium just before surgery
Increase the dose of glibenclamide to 15 mg
Stop glibenclamide before surgery
Stop glibenclamide on the morning of surgery and commence insulin by intravenous infusion
Stop glibenclamide on the morning of surgery and commence insulin by intravenous infusion
The most appropriate answer is to stop glibenclamide on the morning of surgery, using IV insulin and potassium.
This patient is undergoing major surgery, therefore glycaemic control needs to be optimal during this period of extreme stress.
This is best achieved by stopping the glibenclamide on the morning of surgery and starting the patient on IV insulin and IV dextrose with K.
At this time the rate of insulin infusion can then be adjusted according to frequent blood glucose measurements.
50
A 36-year-old woman attends her GP's surgery. She has been diagnosed with hypothyroidism recently and takes thyroxine 100 micrograms daily.
The GP has the benefit of thyroid function and other tests from the previous week.
Which test is the best for monitoring progress and treatment?
```
Free thyroxine levels
Protein bound iodine levels
Thyroid peroxidase antibody levels
Thyroid stimulating hormone (TSH) levels
Triiodothyronine levels
```
Thyroid stimulating hormone (TSH) levels
Thyroxine suppresses the high TSH levels noted in hypothyroidism.
TSH is the best monitoring test and one should aim to get the TSH into the normal range.
51
Which of the following is the commonest clinical manifestation of primary hyperparathyroidism?
```
Bone disease
Constipation
Peptic ulceration
Polyuria
Renal stone disease
```
Renal stone disease occurs in 50 % of patients.
52
A 45-year-old man presents with an ulcer on his right foot. He has a 20 year history of type 1 diabetes and currently uses mixed insulin twice daily.
On examination he has a small ulcer of approximately 2 cm diameter on the outer aspect of his right big toe.
His peripheral pulses are all palpable but he has a peripheral neuropathy to the mid shins. The ulcer has an erythematous margin and is covered by pus.
What is the most likely infective organism?
```
Escherichia coli
MRSA
Pseudomonas aeruginosa
Staphylococcus aureus
Streptococcus pyogenes
```
Staphylococcus aureus
Diabetic foot ulcers can be divided into:
Those in neuropathic feet, and
Those in feet with ischaemia.
The neuropathic foot is warm and well perfused with palpable pulses, sweating is decreased and the skin may be dry and prone to fissures.
The ischaemic foot is cool and pulseless with thin, shiny skin which often lacks hair. There may also be atrophy of the subcutaneous tissues, but intermittent claudication and rest pain may be absent due to co-existent neuropathy.
Diabetic foot infections are common and always serious, and range in severity from superficial paronychia to deep infection and gangrene.
Other manifestations include:
```
Cellulitis
Myositis
Abscesses
Necrotising fasciitis
Septic arthritis
Tendonitis
Osteomyelitis.
All are associated with increased frequency and length of hospitalisation, and risk of lower extremity amputation.
```
Neuropathy, vascular insufficiency and reduced neutrophil function all mean that diabetics are more susceptible to foot ulceration.
Once skin ulceration occurs, the underlying tissues are exposed to colonisation by pathogenic organisms. The inflammatory response is often impaired, and therefore early signs of infection may be subtle. Local signs of wound infection are:
Granulation tissue that becomes increasingly friable
Yellow or grey moist tissue at the base of the ulcer
Purulent discharge and
An unpleasant odour.
The most common pathogens in acute, previously untreated superficial ulcers in diabetic patients are aerobic Gram positive bacteria (particularly Staphylococcus aureus and beta-haemolytic Streptococci).
In patients who have recently received antibiotics or who have deep tissue involvement, infection is usually caused by a mixture of aerobic Gram positive, Gram negative (for example, Escherichia coli, Proteus, Klebsiella) and anaerobic organisms (for example, Bacteroides, Clostridium).
Methicillin-resistant Staphylococcus aureus (MRSA) is more common in patients who have been previously hospitalised or who have received antibiotic therapy, although increasingly it is community acquired.
If infection is suspected, deep swab and tissue samples should be sent for culture and broad-spectrum antibiotics started. The presence of deep infection with abscess, cellulitis gangrene or osteomyelitis is an indication for hospitalisation.
Indications for urgent surgical intervention are:
A large area of infected sloughy tissue
Localised fluctuance and expression of pus
Crepitus in the soft tissues on radiological examination
Purplish discolouration of the skin (which indicates subcutaneous necrosis).
Antibiotic treatment should subsequently be tailored according to the clinical response, culture results and sensitivity. If osteomyelitis is present, surgical resection should be considered and antibiotics continued for four to six weeks.
53
A 62-year-old female with a six year history of type 2 diabetes attends for annual review.
Her HbA1c is 10% (NR
15.5mmol/l
The HbA1c is an important reflection of control over a three month period (life expectancy of the erythrocyte).
There is a good relationship between the rise in glucose and its ability to glycosylate the Hb molecule (there is a difference between average plasma glucose and blood glucose).
Thus a HbA1c of 7% would translate into an average plasma (higher than value of blood glucose) glucose of 9.5 mmol/L and a HbA1c of 10% into 15.5 mmol/L.
This is the reason why so much emphasis is placed on controlling HbA1c rather than the specific glucose measurements, as these vary so much throughout the day.
This is a difficult question and it is very unlikely that you would be asked to translate average blood glucose into an exact HbA1c figure without being provided with a conversion calculator; however, the learning point here is that you realise that the numerical values are not the same.
54
A 45-year-old female attends the diabetic annual review clinic.
Her body mass index has increased over the year to 33.3.
How do you calculate body mass index?
```
Height/Weight
Height/(Weight)2
Weight/Height
Weight/(Height)2
Weight/√ Height
```
BMI is one of the most important calculations of anthropometry and is calculated as weight over (height) squared and measured in kg/m2.
BMI can be described as:
```
Underweight (less than 18.5)
Normal (18.5-24.9)
Overweight (25-29.9)
Obese.
A BMI above 30 diagnoses obesity and has prognostic value indicating increased propensity to develop diabetes, cancer, osteoarthritis and depression.
```
55
A 53-year-old male presents with a three month history of polyuria with polydipsia.
Which of the following measurements would confirm a diagnosis of diabetes mellitus?
A fasting plasma glucose of 6.5 mmol/L
A fasting plasma glucose of 7.5 mmol/l
A plasma glucose of 10 mmol/l at the end of an oral glucose tolerance test
A random glucose of 10.5 mmol/l
A urine dipstick analysis showing +++ glucose
A fasting plasma glucose of 7.5 mmol/l
Diabetes mellitus is diagnosed on the basis of symptoms plus a random glucose above 11.1 mmol/l or fasting plasma glucose above 7 mmol/l or the two hour oral glucose tolerance test.
Impaired glucose tolerance would be indicated by a post OGTT plasma glucose between 7.7 and 11.1 or a fasting plasma glucose between 6.1 and 7.
56
A study reports on the results of a large study of the primary prevention of stroke in a diabetic population using a new antiplatelet agent versus aspirin.
The results of the study reveal that over a five year period the incidence of stroke in the aspirin treated group is 3% compared to a rate of 1.5% in the group treated with the new antiplatelet agent (p
50%
The relative risk reduction is another caculation important for the interpretation of publications.
In this case there is an absolute risk reduction of 1.5% (3 − 1.5%) in stroke afforded by the new agent compared with aspirin yet the relative risk reduction is 1.5/3 = 50%.
That is 50% fewer strokes may be prevented by the use of the newer agent compared with aspirin, although this would be the equivalent of 15 per 1000 patients treated (30 strokes expected/1000 patients treated with aspirin but only 15 with the new drug).
57
Which of the following statements regarding bariatric surgery is correct?
Associated with a significant post-operative mortality
Indicated in patients with a BMI of greater than 30
Contraindicated in adolescents
Indicated in patients with a BMI less than 35 kg/m2
Reduces cardiovascular mortality
Reduces cardiovascular mortality
Bariatric surgery is a major gastrointestinal procedure.
Bariatric surgery in adolescents raises social, psychological and developmental issues, but adolescents are not excluded from surgery, and some hospitals have specialised programmes for younger patients.
Potential candidates for surgery are those with a body mass index (BMI) exceeding 40, or BMI greater than 35 with serious co-morbidities (for example, sleep apnoea, type 2 diabetes).
Post-operative mortality ranges from 0.1-2%.
Vomiting is a risk associated with bariatric surgery, as are dumping syndrome and nutritional deficiencies.
58
A 17-year-old boy has learning difficulties and is seen in the genetics clinic as his maternal uncles also had learning difficulties.
Examination reveals that the patient has large ears and large testes.
What is the most likely genetic diagnosis?
```
47 XYY
Acromegaly
Fragile X syndrome
Klinefelter’s syndrome
Mosaic Down syndrome
```
Fragile X syndrome
In addition to moderate to severe mental retardation other characteristics of individuals with fragile X syndrome may include large ears, macroorchidism, prognathism, speech delays, prominent forehead, double-jointedness, autistic symptoms and occasional self-mutilation. The face is typically long and narrow, with a high arched palate and large ears.
Otitis media, strabismus, and dental problems may be present.
Other common characteristics include hyperextensible joints, hypotonia, and heart problems including mitral valve prolapse.
In males, abnormally large testes are a distinctive feature. In young children, delayed motor development, hyperactivity, behavioural problems, toe walking, and occasional seizures can occur.
59
A 48-year-old male is referred with impotence.
He has a history of angina, hypertension and type 2 diabetes.
Which one of the following drugs that he takes would present a contraindication to his being able to receive sildenafil?
```
Aspirin
Bendroflumethiazide
Isosorbide mononitrate
Lisinopril
Metformin
```
ISMN
Nitrates and sildenafil are contraindicated due to the precipitant drops in blood pressure.
Viagra is also associated with increases in intraocular pressure so should be avoided in glaucoma, hereditary retinal disease and in those with hypotension.
60
A 70-year-old woman is referred by a GP colleague to the hospital with a breast lump.
She is asymptomatic but her investigations reveal:
Corrected calcium 2.72 mmol/L (2.2-2.6)
Phosphate 0.80 mmol/L (0.8-1.4)
Alkaline phosphatase 110 U/L (45-105)
PTH concentration 5.1 pmol/L (0.9-5.4)
Whilst your colleague is away, you are shown these results by one of the receptionists.
What is the most likely diagnosis?
```
Bony metastases
Chronic vitamin D excess
Ectopic PTH related peptide (PTHrp) secretion
Multiple myeloma
Primary hyperparathyroidism
```
Primary hyperparathyroidism
This patient has hypercalcaemia with a borderline low phosphate concentration but an inappropriately normal parathyroid hormone (PTH) concentration.
This suggests hyperparathyroidism which is a relatively common disorder amongst elderly females.
Vitamin D excess would be expected to cause an elevated phosphate.
Bony metastases and multiple myeloma can both result in hypercalcaemia, which should result in a suppressed PTH.
PTH related peptide is a common cause of hypercalcaemia in malignancy. It is not usually detected by normal lab tests for PTH and therefore you would expect a low PTH in the setting of hyperclcaemia.
If this was multiple myeloma you would expect a physiological decrease in PTH as a response to the hypercalaemia. PTH is inappropriately normal here, as mentioned above, which should lead you to a diagnosis of primary hyperparathyroidism.
61
Which of the following is true regarding diabetic foot ulceration?
Autonomic neuropathy results in increased resting blood flow
Callous formation at pressure areas is an important predictor of ulceration
Plantar ulceration is most commonly due to atherosclerosis
Radiography can readily distinguish between Charcot's joint and osteomyelitis
Skin infection is the most common initiating event in ulceration
Callous formation at pressure areas is an important predictor of ulceration
Callous formation at pressure areas is an important predictor of potential ulceration.
Plantar ulceration is usually a consequence of neuropathy and minor skin trauma is probably the most common initiating event.
Blood flow is often decreased with autonomic neuropathy hence sympathectomy may be performed to improve skin blood flow.
It is difficult radiographically to distinguish between Charcot's joint and osteomyelitis.
62
Raised T4 and T3 low TSH
She was taking a variety of drugs for atrial fibrillation, ischaemic heart disease and type 2 diabetes.
Which of the following is most likely to be responsible for these results?
```
Amiodarone
Digoxin
Glibenclamide
Metformin
Simvastatin
```
Amiodarone frequently causes abnormalities in thyroid function tests and may cause both hypothyroidism and hyperthyroidism.
It may cause the former by interfering with the conversion of thyroxine (T4) to tri-iodothyronine (T3) and it may produce the latter either through thyroiditis or donation of iodine (amiodarone contains a large quantity of iodine).
Other side effects of amiodarone include pulmonary fibrosis and photosensitivity reactions.
63
Necrobiosis lipoidica diabeticorum
Necrobiosis lipoidica diabeticorum (NLD) is a painless rash with a central yellowish lipid-like core surrounded by a brownish/purplish periphery.
The condition is found in both type 1 and type 2 diabetes.
Ulceration of the lesion may occur.
NLD may be treated with PUVA therapy and improved therapeutic control.
64
To which of the following drug classes does the oral hypoglycaemic agent pioglitazone belong?
A biguanide
A peroxisome proliferator activated receptor (PPAR)-alpha agonist
A peroxisome proliferator activated receptor (PPAR)-gamma agonist
A sulphonylurea
An alpha-glucosidase inhibitor
A peroxisome proliferator activated receptor (PPAR)-gamma agonist
Pioglitazone belongs to the PPAR gamma agonist class of blood glucose lowering agents.
Through activation of this receptor they modulate adipocyte function and improve insulin sensitivity.
Blood glucose lowering effect is around 1-1.3% HbA1c, but associated adverse events include fluid retention and decreased bone mineral density.
Pioglitazone is contraindicated in patients with a prior history of heart failure.
65
An asymptomatic 56-year-old man with a family history of type 2 diabetes was found to have a fasting venous glucose of 6.5 mmol/L (3.0-6.0).
Which of the following relating to his further investigation is correct?
He has impaired glucose tolerance
He should be investigated further by another fasting venous sampling
He should be treated with oral hypoglycaemics in the first instance
He should undergo a 75 gm oral glucose tolerance test.
This does not need further investigation
He should undergo a 75 gm oral glucose tolerance test.
According to the new revised criteria (WHO 1997) for the diagnosis of diabetes, a fasting venous plasma glucose (VPG) of 6.1 - 6.9 is categorised as impaired fasting hyperglycaemia (IFG). This level requires further assessment with a 75 gram oral glucose tolerance test (OGTT) which is still the gold standard.
A two hour value of equal to or over 11.1 mmol/L is diagnostic of diabetes.
Impaired glucose tolerance is a two hour VPG of 7.8 - 11.1 during an OGT.
Initial treatment of type 2 diabetes is patient education, diet and lifestyle changes.
66
A 35-year-old man presents with weakness and tiredness.
He is noted to be hypertensive. Electrolytes show a hypokalaemia and hypomagnesaemia.
What investigation would you select for this patient?
```
Colonoscopy
Oral glucose tolerance test
Plasma renin to aldosterone ratio
Serum amylase
Serum calcium
```
Plasma renin to aldosterone ratio
This scenario illustrates that young patients with hypertension may have underlying secondary causes.
This patient has primary hyperaldosteronism, which is thought to be a reasonably common cause of hypertension. Primary hyperaldosteronism is associated with high aldosterone, suppressed renin, alkalosis, low potassium, low magnesium and normal/high sodium.
An important differential diagnosis here is renal artery stenosis.
Causes of primary hyperaldosteronism include:
Conn's syndrome (adrenal adenoma) causes over 50%
Adrenal hyperplasia
Adrenal carcinoma (rare)
Glucocorticoid deficiency - also called glucocorticoid-remediable aldosteronism. Note that this is isolated glucocorticoid (cortisol) deficiency driving high ACTH levels and increased aldosterone production. Addison's disease is different as it involves both glucocorticoid and mineralocorticoid deficiencies.
67
```
Interpretation of calcium results
A Addison's disease
B Ectopic PTH secretion
C Hypoparathyroidism
D Osteomalacia
E Paget's disease
F Primary hyperparathyroidism
G Pseudohypoparathyroidism
H Sarcoidosis
I Thyrotoxicosis
J Vitamin D excess
Select the most appropriate diagnosis that best explains the following results.
Normal ranges:
Calcium 2.2-2.6 mmol/L
Phosphate 0.8-1.2 mmol/L
Alkaline phosphatase 50-110 IU/L
PTH 3-5.5 pmol/L
```
Calcium 2.45 mmol/L
Phosphate 1 mmol/L
Alkaline phosphatase 240 IU/L
PTH 3.9 pmol/L
Pagets disease
The first series of results with normal calcium and phosphate but elevated alkaline phosphatase and normal PTH suggests a diagnosis of Paget's disease. Hypercalcaemia usually occurs with immobility. A dramatic rise in alkaline phosphatase may suggest malignant transformation.
68
```
Interpretation of calcium results
A Addison's disease
B Ectopic PTH secretion
C Hypoparathyroidism
D Osteomalacia
E Paget's disease
F Primary hyperparathyroidism
G Pseudohypoparathyroidism
H Sarcoidosis
I Thyrotoxicosis
J Vitamin D excess
```
Select the most appropriate diagnosis that best explains the following results.
```
Normal ranges:
Calcium 2.2-2.6 mmol/L
Phosphate 0.8-1.2 mmol/L
Alkaline phosphatase 50-110 IU/L
PTH 3-5.5 pmol/L
```
Calcium 2.45 mmol/L
Phosphate 1 mmol/L
Alkaline phosphatase 240 IU/L
PTH 3.9 pmol/L
Osteomalacia
The second series of results with lowish normal calcium, low phosphate, elevated alkaline phosphatase and PTH suggests a diagnosis of osteomalacia/vitamin D deficiency. This is a common entity in the elderly and associated with ethnicity. Bone aches and pains together with proximal muscle weakness may feature.
69
```
Interpretation of calcium results
A Addison's disease
B Ectopic PTH secretion
C Hypoparathyroidism
D Osteomalacia
E Paget's disease
F Primary hyperparathyroidism
G Pseudohypoparathyroidism
H Sarcoidosis
I Thyrotoxicosis
J Vitamin D excess
Select the most appropriate diagnosis that best explains the following results.
Normal ranges:
```
```
Normal ranges:
Calcium 2.2-2.6 mmol/L
Phosphate 0.8-1.2 mmol/L
Alkaline phosphatase 50-110 IU/L
PTH 3-5.5 pmol/L
```
Calcium 3.5 mmol/L
Phosphate 0.8 mmol/L
Alkaline phosphatase 320 IU/L
PTH
Ectopic PTH secretion
The third series has elevated calcium, lowish phosphate (arguing against vitamin D excess), elevated alkaline phosphatase and a suppressed PTH concentration. This picture suggests ectopic PTH secretion by a tumour such as a squamous cell carcinoma of the lung. The condition is as a consequence of the secretion of PTH related peptide (PTHrp) which has sequence homology to PTH but does not cross react in assays.
70
```
Medical treatment of tumours
A 5 Fluorouracil
B Bromocriptine
C Dexamethasone
D Gonadorelin analogues
E Mithramycin
F Oestrogen
G Radioactive iodine
H Somatostatin analogues
I Tamoxifen
J Testosterone
From the given list select the most appropriate medical treatment for the following tumours:
```
Prostate cancer
Gonadorelin analogues
Prostate cancer usually expresses testosterone receptors and so responds well to hormonal manipulations that switch off testosterone. Gonadorelin (LHRH) analogues induce hypogonadotrophic hypogonadism and effectively induce a castration.
71
```
Medical treatment of tumours
A 5 Fluorouracil
B Bromocriptine
C Dexamethasone
D Gonadorelin analogues
E Mithramycin
F Oestrogen
G Radioactive iodine
H Somatostatin analogues
I Tamoxifen
J Testosterone
From the given list select the most appropriate medical treatment for the following tumours:
```
Acromegaly
Somatostatin
Acromegaly is due to hypersecretion of growth hormone from a pituitary tumour. The synthetic somatostatin analogues (GHIH - GH inhibitory hormone) suppress GH secretion from these tumours and can be an effective alternative to surgery.
72
```
Medical treatment of tumours
A 5 Fluorouracil
B Bromocriptine
C Dexamethasone
D Gonadorelin analogues
E Mithramycin
F Oestrogen
G Radioactive iodine
H Somatostatin analogues
I Tamoxifen
J Testosterone
From the given list select the most appropriate medical treatment for the following tumours:
```
VIPoma
Somatostatin analogues
VIPomas (vaso-intestinal peptide) are neuroendocrine tumours and as such respond much better to somatostatin therapy than dopamine agonists.
73
```
Medical treatment of tumours
A 5 Fluorouracil
B Bromocriptine
C Dexamethasone
D Gonadorelin analogues
E Mithramycin
F Oestrogen
G Radioactive iodine
H Somatostatin analogues
I Tamoxifen
J Testosterone
```
Oestrogen receptor positive breast carcinoma
Tamoxifen
Breast carcinoma may express oestrogen receptors and in those subjects who are post menopausal, the selective oestrogen receptor modulator, tamoxifen, is a useful adjunct to surgery.
74
```
Medical treatment of tumours
A 5 Fluorouracil
B Bromocriptine
C Dexamethasone
D Gonadorelin analogues
E Mithramycin
F Oestrogen
G Radioactive iodine
H Somatostatin analogues
I Tamoxifen
J Testosterone
```
Metastatic carcinoid syndrome
Metastatic carcinoid syndrome
Carcinoid syndrome is due to a neuroendocrine tumour which expresses somatostatin receptors and the syndrome occurs when there is metastatic load in the liver. The tumour responds extremely well to somatostatin analogues with symptomatic improvement and tumour shrinkage.
75
```
Medical treatment of tumours
A 5 Fluorouracil
B Bromocriptine
C Dexamethasone
D Gonadorelin analogues
E Mithramycin
F Oestrogen
G Radioactive iodine
H Somatostatin analogues
I Tamoxifen
J Testosterone
```
Prolactinoma with suprasellar extension
Bromocriptine
Prolactinomas, even with suprasellar extension, respond extremely well and rapidly to dopamine agonists as dopamine is the inhibitory hormone to pituitary lactotroph secretion.
76
Causes of gynaecomastia
```
A Drug-induced
B Haemochromatosis
C Klinefelter’s syndrome
D Liver disease
E Myotonic dystrophy
F Physiological
G Renal failure
H Testicular tumour
I Thyrotoxicosis
```
A 13-year-old male is brought to the clinic by his parents who are concerned as he has developed a slightly enlarged left breast. He is otherwise well and has progressed normally in school. On examination, he has normal height and weight characteristics and has a small amount of breast tissue in the left breast, which is non-tender. He has scanty pubic hair and testicular volumes of approximately 7 mls bilaterally with developing penis.
Physiological gynaecomastia is common at puberty occurring in as many as 25%. It is characteristically unilateral and when bilateral is usually asymmetrical. It usually resolves spontaneously and reassurance is generally all that is required.
77
```
Causes of gynaecomastia
A Drug-induced
B Haemochromatosis
C Klinefelter’s syndrome
D Liver disease
E Myotonic dystrophy
F Physiological
G Renal failure
H Testicular tumour
I Thyrotoxicosis
```
A 16-year-old male attends clinic concerned regarding poor pubertal development and breast enlargement. He is otherwise well, has just completed schooling but without any qualifications after being in the remedial class. On examination he is tall and is of normal weight, has modest bilateral gynaecomastia, small testicular volumes bilaterally and small penis size. There is only scanty pubic hair but no axillary hair.
Klinefelter's syndrome is characterised by tall stature, gynaecomastia and below average intelligence. Karytotype is XXY and there is a primary hypogonadism with low testosterone and elevated luteinising hormone/follicle-stimulating hormone (LH/FSH) (primary testicular failure).
78
```
Interpreting thyroid function tests
A Free T4 12.1 nmol/L, TSH 7.9 mU/L
B Free T4 18.6 nmol/L, TSH 0.07 mU/L
C Free T4 34 nmol/L, TSH 3.9 mU/L
D Free T4 55 nmol/L, TSH
```
Free T4 34 nmol/L, TSH 3.9 mU/L
A TSH secreting pituitary tumour, which is rare, is associated with a raised T4 but a TSH within the normal range or slightly elevated. Clearly a T4 that is elevated should suppress TSH concentrations and therefore if the TSH is not suppressed then this suggests a problem with pituitary TSH secretion.
79
```
Interpreting thyroid function tests
A Free T4 12.1 nmol/L, TSH 7.9 mU/L
B Free T4 18.6 nmol/L, TSH 0.07 mU/L
C Free T4 34 nmol/L, TSH 3.9 mU/L
D Free T4 55 nmol/L, TSH
```
Free T4 55 nmol/L, TSH
80
```
Interpreting thyroid function tests
A Free T4 12.1 nmol/L, TSH 7.9 mU/L
B Free T4 18.6 nmol/L, TSH 0.07 mU/L
C Free T4 34 nmol/L, TSH 3.9 mU/L
D Free T4 55 nmol/L, TSH
```
Free T4 18 nmol/L, TSH 2.8 mU/L
Obesity does not cause any abnormality of thyroid function and would typically be associated with normal thyroid function.
81
```
A 42-year-old man is seen in the clinic reporting lethargy, nausea and vomiting and weight loss. On examination he is hypotensive and there is pigmentation of his palmar skin creases and of an old appendicectomy scar.
Routine biochemistry reveals:
Potassium 5.8 mmol/L (3.5-4.9)
Sodium 131 mmol/L (137-144)
What is the likely diagnosis?
```
```
Addison's disease
Conn's syndrome
Cushing's syndrome
Hypopituitarism
Waterhouse-Friderichsen syndrome
```
These features are classical of primary hypoadrenalism, Addison's disease or adrenal insufficiency, which usually has an autoimmune aetiology as the pigmentation is due to increased adrenocorticotropic hormone (ACTH), hence we can say primary.
Waterhouse-Friderichsen syndrome is an acute adrenal insufficiency due to bilateral haemorrhage in patients with severe sepsis, often meningococcal septicaemia.
Hypopituitarism would not cause increased pigmentation as ACTH would be low.
Conn's syndrome is primary hyperaldosteronism due an aldosterone producing adrenal tumour.
Cushing's syndrome occurs as a result of excess glucocorticoids.
82
A 41-year-old woman presents with a history of weight loss and anxiety.
She has a three year history of thyrotoxicosis for which she has been treated with previous courses of carbimazole but has failed to attend scheduled outpatient appointments for over one year.
Following the course of carbimazole which was stopped approximately two years ago she felt much better but was still aware of a goitre. Most recently she has become aware of a more prominent swelling of the right side of the neck and her symptoms of anxiety with a 3 kg weight loss. Currently she takes no medication but is a smoker of 10 cigarettes daily.
On examination she has, a pulse of 96 beats per minute, a fine tremor of the outstretched hands, lid lag and some periorbital puffiness. There is a moderately enlarged and diffuse goitre with a more prominent 3 cm nodule on the left of the gland which is non-tender. Over the goitre is a bruit and no lymphadenopathy is palpable. No other abnormalities are noted.
```
Investigations reveal:
Free T4 37.3 pmol/L (10-22)
TSH 0.05 mU/L (0.4-5)
Thyroid peroxidase antibodies
1:2400 U/L I123 uptake scan
```
Diffuse uptake with no uptake in left nodule
What is the most likely cause of the thyroid nodule?
```
De Quervain's thyroiditis
Graves' disease
Medullary carcinoma of the thyroid
Papillary carcinoma of the thyroid
Toxic multinodular goitre
```
Papillary carcinoma of the thyroid
This woman has hyperthyroidism but the prominent nodule which is 'cold' on uptake scanning is highly suggestive of thyroid carcinoma and the mostly likely diagnosis is Graves' disease (periorbital puffiness and thyroid bruit) associated with papillary thyroid carcinoma.
Thyroid cancer associated with Graves' disease is not uncommon and usually due to papillary carcinoma and must be considered in suspicious/expanding nodules rather than attributing purely to Graves' disease.
Thyroid peroxidase antibodies are found in more than 70% of cases of Grave's disease.
