endocrinology best r

8/13/2019 Endocrinology Best r

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Endocrinology 1

Endocrinology

A child aged 10 days has ambiguous genitalia. Which of the following may be causative.

Available marks are shown in brackets

1 )if a buccal smear is chromatin negative there is a serious risk of an Addisoniancrisis

[0]

2 )a raised urinary output of pregnanetriol would confirm a diagnosis of congenitaladrenal hyperplasia

[100]

3 ) the finding of the genotype 45 XO would reliably explain the anomaly [0]

4 )if testicles are present in the "labia" an acceptable explanation would beKlinefelter's syndrome

[0]

5 )

the most important factor in deciding the sex to which the child should be

assigned is the genetic (chromosomal) sex [0]

Comments:If the buccal smear positive ie female then there would be at increased risk of salt crisis. Saltlosers presenting in newborn period with crisis are more likely to be female. The commonestcause of ambiguous genitalia at birth is CAH, of which 95% are deficient in 21-hydroxylase.Less common enzyme defects involve 11B hydroxylase, and 3B hydroxysteroiddehydrogenase. About 2/3 of 21-hydroxylase are salt losers, and present with an hypoadrenalcrisis. There is normal male genitalia in 47 XXY Klinefelters and Turners - XO. In intersexstates, the assignation of sex is not totally based on the karyotype.

Which of the following doses of prednisolone is equivalent in its glucocorticoid potency to

20mg of hydrocortisone.


1 ) 2 mg [0]

2 ) 5 mg [100]

3 ) 10 mg [0]

4 ) 15 mg [0]

5 ) 20 mg [0]

Comments:It is important to know the relative potencies of the glucocorticoids. Dexamethasone forinstance is roughly 30 times more potent than hydrocortisone.

A 15 year old girl is referred by her general practitioner with agitation and weight gain. Hermother accompanies her during the consultation and explains that over the last 2 months she


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Endocrinology 2

has become increasingly agitated with poor sleep. Her progress at school has up until recently,been fine, although of late she has been apathetic. She has no past medical history of note,although family history reveals that her mother was treated for an 'overactive thyroid' and nowtakes thyroxine tablets. Examination reveals no specific abnormalities with a blood pressure of112/70 mmHg and a BMI of 20. Her GPs letter reveals the following results:TSH 3.2 mU/L (0. 35 - 5.0)

Total T4 250 nmol/L (55 - 144)free T4 12.9 pmol/L (9 - 24)Total T3 3.2 nmol/L (0. 9 - 2.8)free T3 3.8 pmol/l (3.0-5.8)What is the likely explanation for her presentation and results?


1 ) Bulimia Nervosa [0]

2 ) Dysthyroglobulinaemia [0]

3 ) Factitious Thyrotoxicosis [0]

4 ) Graves Disease [0]

5 ) Pregnancy [100]

Comments:This young girl has normal TFTs as reflected by free T4, T3 and normal TSH. However, hertotal T4 and T3 are elevated suggesting elevated Thyroid Hormone Binding, a feature ofpregnancy. Dysthyroglobulinaemia - Pendred's syndrome is a combination of Hypothyroidism,goitre and Deafness.

A 16 year old female patient is refered with primary amenorrhoea. Investigations reveal a 46XY karyotype. Which of the following concerning the condition is true?


1 ) A diagnosis of Turner's syndrome is likely [0]

2 )It is likely that her mother received Carbimazole for thyrotoxicosis duringpregnancy

[0]

3 ) Low testosterone and oestradiol concentrations would be expected [0]

4 ) The diagnosis is likely to be testicular feminisation syndrome [100]

5 ) The diagnosis is Noonan's syndrome [0]

Comments:A female phenotype can occur in testicular feminisation, a condition associated with androgeninsensitivity due to an androgen receptor defect. Stilboestrel therapy has been associated withthe induction of loatent tumours and to influence sexual behaviour but is not associated withabnormalities of sexual identity. In Noonan's syndrome, infants are males but physical features

resemble that found in Turner's syndrome. Neither prednisolone nor maternal thyrotoxicosiswould cause gender mal-assignment problems.

In a boy of 7 who was operated upon for a craniopharyngioma, which of the following disorderscan be expected to develop over the next couple of years:



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Endocrinology 3

1 ) Diabetes mellitus [0]

2 ) hyponatraemia [0]

3 ) poor growth [100]

4 ) Precocious puberty [0]

5 ) Spastic diplegia [0]

Comments:Pan hypopituitarism following surgical treatment would be expected, hence poor growth.Diabetes insipidus and hypernatraemia rather than hyponatraemia may be observed. Delayedpuberty would be expected rather than precocious puberty. Spastic diplegia would suggestextensive lateral expansion, which would not be expected. Diabetes mellitus is not a usualconsequence.

The thyroid hormone receptor is:


1 ) A gated ion channel [0]

2 ) A cell surface receptor [0]3 ) A cytoplasmic protein [0]

4 ) A G-protein coupled receptor [0]

5 ) A nuclear receptor [100]

Comments:The thyroid hormone receptor is a nuclear receptor. When it binds T3 it is able to bind to thethyroid hormone response element (TRE) in the promoter region of thyroid hormoneresponsive genes and initiates transcription.

Which one of the following options would not be expected in association with poorly controlledhypothyroidism in an 18 month old infant?


1 ) High plasma TSH concentration [0]

2 ) Delayed bone age [0]

3 ) Umbilical hernia [0]

4 ) Diarrhoea [100]

5 ) delayed development milestones [0]

Comments:High plasma TSH concentration with low Free Thyroxine level would occur. Thyroid hormoneis a prerequisite for normal growth and cognitive /psychomotor development so bone age anddevelopmental milestones would be delayed. Umbilical herniae are a feature. Constipation is a

feature rather than diarrhoea.

2 week old male child is brought to casualty by his concerned parents with diarrhoea andvomiting. He is the first child of a young couple. Examination reveals few features besidesobvious dehydration. He is noted to have a penile length of 3.5cms. Which of the following isthe most appropriate inital treatment for this patient?



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Endocrinology 4

1 ) Cow's milk allergy is the most likely diagnosis [0]

2 ) gluten-enteropathy should be excluded [0]

3 ) Requires urgent treatment with oral steroids [0]

4 ) Requires urgent treatment with IV normal saline [100]

5 ) Rota virus gastroenteritis is the most likely diagnosis [0]

Comments:The history suggests a diagnosis of classical congenital adrenal hyperplasia which iscommonly due to 21 hydroxylase deficiency. A variable presentation is typical but neonatalpresentations include salt losing crisis, penile development in the male virilisation andambiguous genitialia in females. Patients should initially be resuscitated with fluid, usuallysaline and if suspicious, urgent biochemistry requested for cortisol, 17OHP etc prior toadministration of intravenous steroids.

A 16 year old female presents with hypertension and increasing weight. Which of the followingfeatures would be most suggestive of Cushing's syndrome rather than simple obesity?

Available marks are shown in brackets1 ) Abdominal striae [0]

2 ) Acanthosis Nigricans [0]

3 ) Buffalo Hump (interscapular fat pad) [0]

4 ) Moon face [0]

5 ) Proximal myopathy [100]

Comments:Proximal myopathy, easy bruising and thin skin are clinical features that are most suggestiveof Cushing's syndrome. Otherwise, abdominal striae, buffalo hump, and acanthosis nigricansare all features of obesity. Similarly Oligomennorhoea would be a feature of obesity/polycysticovarian syndrome.

Which ONE of the following is true concerning Antidiuretic hormone (ADH)?


1 ) Carbamazepine potentiates it's release [100]

2 ) Ethanol potentiates it's release [0]

3 ) It circulates in the blood bound to neurohypophysin [0]

4 ) It is a cyclic octapeptide [0]

5 ) It is synthesised in the posterior pituitary [0]

Comments:

ADH is a nonapeptide manufactured in the paraventricular and supra-optic nuclei of thehypothalamus and released from the posterior pituitary. It acts on the collecting ductsimproving water permeability and hence water retention. Carbamazepine as well as otheragents such as thiazides and SSRIs may potentiate its release. Ethanol usually inhibitsrelease.

A 14 day old boy is admitted with collapse. She was born at 38+2/40 weighing 3.47kg to ahealthy Caucasian mother. Pregnancy and delivery had been uncomplicated. Followingdischarge she had failed to gain weight, and began vomiting 3 days ago. This had persisted


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Endocrinology 5

and worsened. Over the past 2 days the nappies had been wet twice a day.

On examination temperature 36.2C(tympanic), HR 160/min (thready pulses), RR 40/min. Nomurmur, chest clinically clear. Abdomen soft with no organomegaly. O2 saturations 85% in air.

Blood tests show:

Na 127 mmol/l

K 5.8 mmol/l

Urea 13.7 mmol/l

Creatinine 74

What is the most likely diagnosis?


1 ) Congenital adrenal hyperplasia [100]

2 ) Congenital heart disease [0]

3 ) Inborn errors of metabolism [0]

4 ) Sepsis [0]

Comments:

The picture is one of shock in a child who has become progressively dehydrated. Sepsis andcongenital heart disease are possible, but there is nothing specific to point in these directions.The electrolytes make the likely diagnosis salt-losing congenital adrenal hyperplasia.

An 11 year old girl is admitted with drowsiness and difficulty in breathing. She was well until 3weeks ago when she began feeling tired and losing weight. She has been very thirsty and has

been drinking lots of lucozade (high glucose drink) to give her energy. There is no other historyof note. Mother has 'thyroid disease'.

On examination she reponds only to pain. She has deep sighing breathing at 15/min, and aheart rate of 100/min. Her temperature is 36.8C (tympanic). Oxygen saturations are 97% inair. She has cool peripheries and a capillary refill time of 4 seconds.



1 ) Child abuse [0]

2 ) Hepatic failure [0]

3 ) Hypoglycaemia [0]4 ) Diabetic ketoacidosis [100]

5 ) Substance abuse [0]

Comments:

The history of weight loss, polydipsia and polyuria over 3 weeks suggest diabetes mellitus.Other autoimmune diseases run in the family. She has decreased level of consciousness,


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Endocrinology 6

early shock and Kussmaul breathing so the diagnosis is diabetic ketoacidosis. The BM stixhere was 48 mmol/l.

Which of the following is correct concerning Type 1 Diabetes in children.


1 ) Insulin therapy should be given only when oral hypoglycaemic agents fail [0]

2 ) There is a strong hereditary component [0]

3 ) The onset of the disease is usually acute [100]

4 ) Retinopathy is commonly seen upon diagnosis. [0]

5 )The adequacy of glycaemic control is most reliably assessed by twice dailyurinalysis

[0]

Comments:The disease often presents with ketoacidosis. The genetic associations in type 1 Diabetes areless strong. For example the risk of Type 1 Diabetes developing in the child is 6.3% if thefather is affected and 1.3% if the mother is affected. Insulin therapy is given initially.

Microvascular complications do not usually appear till 5-10 years after the diagnosis.Glycaemic control can be assessed by capillary glucose testing and measurement of HbA1C.

Which of the following statements applies to Precocious puberty:


1 ) Is less common in girls [0]

2 ) In boys it is usually idiopathic [0]

3 ) Is a well recognised sequel to hydrocephalus [100]

4 ) Is associated with a normal rate of skeletal maturation [0]

5 ) Is treated with LHRH antagonists. [0]

Comments:Precocious puberty is approximately five times more common in females. In females it is usually idiopathic, inmales the commonest cause is a hypothalamic hamartoma. CNS disorders such as hydrocephalus, head trauma,cerebral palsy and meningitis are aetiological factors.

Skeletal maturation is accelerated. The condition is treated with LHRH agonists.

Which of the following techniques would be most useful in the differential diagnosis betweenectopic Cushing's syndrome and pituitary dependent Cushing's disease.


1 ) Urine free cortisol [0]

2 ) High dose Dexamethasone suppression test [0]

3 ) ACTH concentrations [0]

4 ) Inferior petrosal sinus sampling [100]

5 ) CRF test [0]

Comments:Inferior petrosal sinus sampling with an elevated central ACTH concentration compared withthe peripheral value is the most valuable test in the differential diagnosis of either Cushing'sdisease or ectopic Cushing's syndrome. The other tests are far less useful in comparison.


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Endocrinology 7

Which of the following is true regarding male sexual development:


1 )The apex of the physical strength spurt antedotes the peak height velocity by sixmonths

[0]

2 ) Sperm production begins in the early stages [100]

3 ) The earliest detectable evidence is pubic hair growth [0]

4 ) The average prepubertal penile length is 8cm [0]

5 ) The average testicular volume in the adult is 15ml [0]

Comments:

The strength spurt occurs after the pubertal growth spurt. Spermatogenesis is commonlyapparent from the age of 11 years and upwards, however motility, morphology andconcentration do not reach adult levels till 17 years.

The earliest detectable evidence of puberty in males is the increase in testicular size(length of2.5cm and a volume of 4mls).The average prepubertal penile length is 6.4cm The averagetesticular volume in the adult is around 20-25mls.

Causes of hypoadrenalism include:


1 ) Hughes' syndrome (anti-phospholipid antibody) [100]

2 ) MEN type 2a [0]

3 ) VonHippel-Lindau [0]

4 ) Pendred's syndrome [0]

5 ) McArdle's syndrome [0]

Comments:The anti-phospholipid syndrome is one of the commoner causes of Hypoadrenalism and mayprecipitate adrenal infarction and haemorrhage through adrenal vein thrombosis.

A 16 year old male with a day history of malaise, weakness and vomiting. He was diagnosedwith Insulin dependent diabetes mellitus 3 years prviously. Which ONE of the followingsupports a diagnosis of diabetic ketoacidosis:


1 ) Abdominal pain at onset [0]

2 ) A serum bicarbonate of 10 mmol/l [100]

3 ) A serum glucose 14 mmol/l [0]

4 ) Decreased appetite in the past few days [0]

5 ) Shallow respirations [0]

Comments:a-An unusual but recognised feature particularly in children. However does not support adiagnosis of DKA. b-Suggests metabolic acidosis. c-'Normoglycaemic DKA' can occur and a


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Endocrinology 8

glucose of 14 doesn't rule out the diagnosis but it does not support the diagnosis. d-Usuallypatients are unwell with infections and anorexia. e-Respiratory compensation leads to rapiddeep (Kussmaul's) breathing. (Dr Mike Mulcahy)

A 17 year-old male student presents with a three week history of thirst, polyuria, balanitis andweight loss. What is the most appropriate next investigation?


1 ) 75 g glucose tolerance test [0]

2 ) Fructosamine concentration [0]

3 ) HbA1c [0]

4 ) Random plasma glucose concentration [100]

5 ) Urinary ketones [0]

Comments:

This patient obviously has diabetes mellitus and the diagnosis should be confirmed with either

a fasting plasma glucose above 7 mmol/l or a random plasma glucose above 11.1 mmol/l.

Which one of the following statements is correct concerning Glucose-6-phosphate

dehydrogenase deficiency?


1 ) it is inherited as an autosomal dominant condition. [0]

2 ) The condition is more severe in males. [0]

3 ) Is associated with drug induced haemolysis [100]

4 ) Is an indication for splenectomy [0]

5 ) blood transfusions are not indicated. [0]

Comments:G6PDH deficiency is an X linked recessive condition. It manifests more commonly in males but

is not more severe. Drugs which cause haemolysis include aspirin, antimalarials, antibacterialsand sulphonamides. Splenectomy is not helpful in the management of this condition. Bloodtransfusions may be life saving.

A four year old boy presents in coma. For the previous few nights he has been enuretic,although previously dry. On admission he is dehydrated and his breath has a peculiar sweetsmell. Blood gas analysis shows pH 7.12, pO2 95mmHg, pCO2 15mmHg, HCO3 10mmol/l.Which one of the following statements is correct?


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Endocrinology 9


1 ) He has lactic acidosis [0]

2 ) He has respiratory acidosis [0]

3 ) Rehydration should be very slow in case of precipitating cardiac failure [0]

4 ) The initial fluid of choice is 4% dextrose/0.18% saline solution [0]

5 ) His breath will have a characterisitic smell of ketones [100]

Comments:His features are consistent with diabetic ketoacidosis and include history of enuresissecondary to polyuria, dehydration and ketotic breath. He has a metabolic acidosis asbicarbonate levels are low. Rehydration should be relatively quickly, however over vigorouscorrection of the fluid deficit will precipitate cerebral oedema. The initial choice of fluid is 0.9%saline normal saline

A 3 month old boy is admitted unwell. Investigations reveal a hypokalaemic alkalosis. Which ofthe following may be responsible for this metabolic disturbance?

Available marks are shown in brackets1 ) feeds that are too concentrated [0]

2 ) congenital pyloric stenosis [100]

3 ) cystic fibrosis [0]

4 ) previous urinary diversion [0]

5 ) renal failure [0]

Comments:Metabolic alkalosis with hypokalemia is seen in pyloric stenosis because of the loss ofstomach acid with K and HCl, and cystic fibrosis as in pseudo Bartter syndrome. Renal failureand urinary diversion cause metabolic acidosis. Bartter syndrome is a form of renal K wastingwith elevated renin and aldosterone, the K is usually


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Endocrinology 10

1 ) Concentrations are reduced in pregnancy [0]

2 ) Concentrations are elevated in hepatic cirrhosis [0]

3 ) Concentrations are usually elevated in adult growth hormone deficiency [0]

4 ) Concentrations are reduced in starvation [100]

5 ) Concentrations are elevated in diabetes mellitus [0]

Comments:IGF-1 concentrations are often increased in pregnancy. Reduced IGF-1 is typically found inadult GHD, Cirrhosis of the liver due to reduced synthesis, diabetes mellitus and starvation.

Which ONE of the following is a recognised feature of achondroplasia?


1 ) Autosomal recessive inheritance [0]

2 ) May be diagnosed radiologically at birth [100]

3 ) Increased liability to pathological fractures [0]

4 ) Shortened spine [0]5 ) Subfertility [0]

Comments:ACHONDROPLASIA is an autosomal dominant condition and one of the commonest forms ofinherited dwarfism. Epiphyseal dysplasia - thin zone of cartilage cells, diminished columnararrangement short thick bones, spinal length almost always normal. Features - short limbs,normal trunk, large head, saddle nose, exagerrated lumbar lordosis normal mental and sexualdevelopment, spinal problems. Homozygotes - neonatal death (Harrisons)

Which of the following is a glycoprotein hormone?

Available marks are shown in brackets1 ) Growth hormone releasing hormone [0]

2 ) Cortisol [0]

3 ) Thyrotropin releasing hormone (TRH) [0]

4 ) Thyrotropin (TSH) [100]

5 ) Oxytocin [0]

Comments:Thyrotropin is glycosylated, cortisol is a steroid hormone and the others are peptidehormones/neuropeptides which as a group are rarely glycosylated.

Which of the following is associated with hypernatraemia.


1 ) Cholera [0]

2 ) Pyloric stenosis [0]

3 ) Inappropriate ADH secretion [0]

4 ) Diabetes insipidus [100]

5 ) Diabetes mellitus [0]


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Endocrinology 11

Comments:Cholera results in excessive water and sodium losses and hence hyponatraemia. Pyloricstenosis typically results in hypokalaemic, hypochloraemic, metabolic alkalosis and not causehypernatraemia. Inappropriate ADH secretion causes hyponatraemia. In Diabetes insipidusfailure to concentrate urine results in hypernatraemic dehydration with hyperosmolarity. Poorly

controlled diabetes results in osmotic diuresis and renal sodium loss.

A 12 year old child presents with pelvic pain and bowing of the tibia. A diagnosis ofosteomalacia is suspected. Which one of the following statements is true regardingosteomalacia?


1 ) Bone biopsy would show an increase in mineralised osteoid [0]

2 ) Is due to vitamin A deficiency [0]

3 ) May present with pseudo-fractures [100]

4 ) Serum calcium is increased [0]

5 ) Typically causes a distal myopathy [0]

Comments:Osteomalacia is due to vitamin D deficiency. It can result from malabsorption, renal disease(familial hypophosphataemic rickets), chronic renal failure and anticonvulsant therapy. It oftenpresents with bone pain and a proximal myopathy. The psuedo-fractures in the hip are termedLoosers zones. Serum calcium is low. A bone biopsy would show an decrease in the amountof mineralised osteoid.

Which one of the following statements is true concerning congenital hypothyroidism:


1 ) Bone age is usually normal. [0]2 ) Has an incidence of 1 in 15,000 [0]

3 ) Is a cause of bilateral inguinal herniae [0]

4 ) Requires children to be placed in special schooling [0]

5 ) Is best monitored by regular assessment of height velocity [100]

Comments:

Congenital hypothyroidism is associated with delayed bone age. The incidence is one in 4000.The condition is associated with umbilical herniae and not inguinal herniae.

Intellectual function and cognitive development may be impaired if the condition remains

untreated or in cases of severe cretinism, which is rare. The rate of linear growth is retarded inthis condition and is always less than weight gain.

Which of the following is a feature of pseudohypoparathyroidism?


1 ) Increased urinary phosphate and cAMP with PTH infusion [0]

2 ) Low serum PTH [0]


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Endocrinology 12

3 ) Low serum calcium and low serum phosphate [0]

4 ) Low serum calcium and high serum phosphate [100]

5 ) Shortened 2nd and 3rd metacarpals [0]

Comments:The biochemistry shows a hypocalcaemia with hyperphosphataemia being usual but elevatedPTH due to resistance to parathormone (PTH). This is due to mutation of the PTH receptorwith abnormality of the Gsalpha subunit with reduced cAMP production following a PTHinfusion. There are associated phenotypic signs including short stature, low IQ and shortened4th and 5th metacarpals.

A 16 year old female with Addisons disease is intolerant of her hydrocortisone treatmentwhich she takes at a dose of 20mg in the morning and 10mg in the evening. Which of thefollowing doses of prednisolone would provide an equivalent daily dose as her hydrocortisone?


1 ) 5mg [0]

2 ) 7.5mg [100]

3 ) 10mg [0]

4 ) 12.5mg [0]

5 ) 15mg [0]

Comments:The equivalent ratio of prednisolone to hydrocortisone is 1:4. For Dexamethasone tohydrocortisone the ratio is roughly 1:40.

An 18 year old woman is noted to have persistent polyuria in excess of 4 l itres per day whilstrecovering from a head injury she sustained in a road traffic accident. Investigations reveal:

potassium 4.1 mmol/L (3.5-4.9)

calcium 2.4 mmol/L (2.2-2.6)

glucose 5.6 mmol/L (3.0-6.0)

Which one of the following is the most effective method of confirming the diagnosis?


1 ) autoantibodies to vasopressin neurones [0]

2 ) MRI of the hypothalamus and pituitary [0]

3 ) therapeutic trial of low dose DDAVP [0]

4 ) vasopressin concentration [0]

5 ) water deprivation test [100]

Comments:The history and confirmed polyuria are suspicious of diabetes insipidus which is notuncommon after head injury. This can be confirmed with a water deprivation test where failureof urine concentration would be expected. A MRI of the pituitary and hypothalamus may show


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Endocrinology 13

no abnormality but would be undertaken after the diagnosis of DI is confirmed. Similarlyanterior hormone assessment would also be undertaken after the diagnosis is confirmed. Atherapeutic trial of DDAVP is only appropriate if the diagnosis of DI is confirmed as primarypolydipsia can also be a feature of trauma and in these circumstances DDAVP may precipitatehyponatraemia. Autoantibodies to ADH neurones are irrelevant.

A 17 year female presents with tingling and muscle cramps. There is no other past medicalhistory of note. Investigations reveal

Creatinine 68 micromol/L (50-100)

calcium 1.76 mmol/L (2.2-2.6)

albumin 38 g/L (37-49)

Which one of the following investigations is most likely to confirm the diagnosis?


1 ) Alkaline phosphatase concentration [0]

2 ) CT brain scanning [0]

3 ) PTH concentration [100]

4 ) Urine calcium concentration [0]

5 ) Vitamin D concentration [0]

Comments:

This patient has low calcium which could be due to either Vitamin D deficiency orhypoparathyroidism. The most likely cause in a young patient who has otherwise been quitewell with normal renal function would therefore be hypoparathyroidism. Urine calciumconcentrations are useful in familial hypercalciuric hypercalcaemia.

A 18 year-old girl presents with anxiety and palpitations. Her mother had been treated for anoveractive thyroid gland having received radioiodine and was now on Thyroxine replacementtherapy. On examination she had a pulse of 104 bpm with a fine tremor and lid lag. There wasno goitre palpable.

Investigations revealed:

serum free T4 33 pmol/L (10-20)

plasma thyroid stimulating hormone (TSH)


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Endocrinology 14

2 ) familial hyperthyroglobulinaemia [0]

3 ) Hashitoxicosis [0]

4 ) Graves disease [100]

5 ) Riedels thyroiditis [0]

Comments:

Although the lead-in might make you think that this patient could gain access to thyroxine andso a diagnosis of factitious hyperthyroidism is possible, in practice this is extremely unlikely. Astrong family history of thyrotoxicosis is typical for Graves' disease and the absence of a goitrewith the absence of TPO antibodies (found in 80% of Graves cases) again is compatible with adiagnosis of Graves.

A patient is receiving treatment with recombinant human growth hormone. Which of thefollowing is a recognised side effect of GH therapy?


1 ) Prostatic hypertrophy [0]2 ) Melanoma [0]

3 ) Benign intra-cranial hypertension [100]

4 ) Prolongation of the QT interval [0]

5 ) Osteoporosis [0]

Comments:GH is rarely associated with BIH, the mechanism probably is related to fluid retention. Thecommonest side effect of GH therapy is fluid retention, though other side effects includegynaecomastia, hypertension and atrial fibrillation. BPH has not been reported.

Which of the following statements apples to Diabetes in adolescence:


1 ) Is usually associated with a decreased insulin requirement [0]

2 ) Is associated with high levels of IGF-1 [0]

3 ) Causes a delayed menarche in girls. [0]

4 ) If poorly controlled causes reversible retinopathy [0]

5 ) Is compatible with holding a full driving licence [100]

Comments:

Diabetes in adolescence is associated with insulin resistance and increased insulin

requirement. IGF-1 levels are lower than in control subjects.

Delayed menarche occurs only if there is significant undernutrition as a consequence of poorcontrol or an eating disorder.

The retinopathy is not often reversible. There is no contraindication to holding a licence ifhypoglycaemia without warning and major visual complications do not develop.


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Endocrinology 15

Which of the following is commonly associated with congenital hypothyroidism in the neonatalperiod:


1 ) hypothermia [100]

2 ) Diarrhoea [0]

3 ) Prolonged conjugated hyperbilirubinaemia [0]

4 ) A small anterior fontanelle [0]

5 ) Inguinal hernia [0]

Comments:Hypothermia results from reduced metabolic rate. Constipation rather than diarrhoea is acommon clinical feature. Prolonged conjugated hyperbilirubinaemia is a relatively uncommonsequelae. The anterior fontanelle would be tense. Umbilical rather than inguinal herniae areassociated.

A 16 year old girl with obesity was referred with abdominal swelling and mild ankle oedema.On examination the blood pressure was 140/90 mmHg. Investigations revealed: Haemoglobin10.5g/dL (11.5-16.5), Serum biochemistry normal, Serum albumin 34 g/L (37-49), Urinedipstick proteinuria + Which investigation should be performed next?


1 ) 24 hour urinary protein estimation. [0]

2 ) Abdominal ultrasound. [0]

3 ) Plasma protein electrophoresis. [0]

4 ) Urinary albumin: creatinine ratio. [0]

5 ) Urinary B-human chorionic gonadotrophin test (B-HCG) [100]

Comments:This young girl has been gaining weight, has abdominal swelling and ankle oedema. She ishypertensive and has a mild anaemia with proteinuria. These signs should ring a bellsuggesting a concealed pregnancy with pre-eclampsia. The most relevant investigation wouldbe a pregnancy test urinary B-HCG.

An 18 month old boy investigated for failure to thrive and delayed development is found tohave primary hypothyroidism. Which of the following statements applies to his condition.


1 )He is unlikely to achieve normal intelligence despite immediate commencementof appropriate treatment

[100]

2 )If his bone age was 3 months the onset of his hypothyroid state is most likely tohave occurred at 3 months of age

[0]


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Endocrinology 16

3 ) Growth hormone deficiency is likely also to be associated [0]

4 ) Hashimotos disease is the most likely cause. [0]

5 ) He is more prone to develop parathyroid insufficiency [0]

Comments:The diagnosis of congenital hypothyroidism has been delayed and hence thyroxine therapy willnot restore mental function fully. The hypothyroidism is likely to have been present at birth.Growth hormone deficiency may be seen in association with secondary hypothyroidism ifpituitary insufficiency exists, but not in primary hypothyroidism. The most likely aetiology isabsent or ectopic thyroid. Hypoparathyroidism is unrelated.

A 17 year old female attends clinic complaining of hirsuitism and oligomennorhoea. Which ofthe following would be most suggestive of a diagnosis of Polycystic Ovarian Syndrome?


1 ) Increased androstenedione concentration [100]

2 ) Increased insulin concetration [0]

3 ) Increased Prolactin concetration [0]4 ) Increased FSH concetration [0]

5 ) Increased Sex Hormone binding globulin (SHBG) concentration [0]

Comments:PCOs is associated with a raised LH:FSH ratio, with insulin resistance and hyperandrogenismas evidenced by raised androstenedione and slightly raised testosterone. Elevated prolactinconcentrations although a feature of PCOs is not specific of the diagnosis and may suggestmicroprolactinoma. Although insulin resistance is a feature of PCOs, a raised insulinconcentration is rather irrelevant and no one would measure this in clinical practice. It is oftenelevated in association with testosterone secreting tumours.

Which of the following is associated with Congenital Adrenal Hyperplasia?


1 ) Delayed puberty [0]

2 ) Hypopigmentation [0]

3 ) Hyporeninaemia [0]

4 ) Persistent Wolffian duct [0]

5 ) Premature epiphyseal closure [100]

Comments:

Premature epiphyseal closure is a classical feature of CAH, and is secondary to high levels ofsex steroids. Under, and over treatment of CAH patients puts patients at risk of short stature,over treatment because of the glucocorticoid induced inhibition of the growth axis. CAH isassociated with precocious puberty caused by long term exposure to androgens,which activatethe hypothalamic-pituitary-gonadalaxis.

Similarly, CAH is associated with hyperpigmentation, and hyperreninaemia due to sodium lossand hypovolaemia. The Wolffian duct is never formed in CAH.


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Endocrinology 17

Which of the following statements is correct concerning puberty:


1 ) In girls the first sign is the appearance of pubic hair [0]

2 ) In boys the first sign is enlargement of the testes [100]3 ) Precocious puberty is more common in boys [0]

4 )Once the epiphyses of the long bones fuse with the metaphyses there is nofurther growth in stature

[0]

5 ) In girls menarche coincides with the peak of the growth spurt [0]

Comments:

The first sign of puberty in the female is breast development, termed thelarche. Enlargement ofthe testes of greater than 2.5cm in length or 4 mls in volume is a reliable indicator of puberty.

Precocious puberty is approximately five times more common in femnales. Ossification centres

appear in early life, and ultimately the epiphysis or growth plate will fuse with the shaft of thelong bones and from then further growth will not occur. Most females have reached peakheight velocity 1.3 years before menarche.

A 17 year-old girl presents with vomiting and her investigations show:

sodium 120 mmol/L (137 - 144)

potassium 3.0 mmol/L (3.5-4.9)

urea 2.2 mmol/L (2.5 - 7.5)

urine sodium 2 mmol/L

urine osmolality 700 mosmol/kg (350 - 1000)



1 ) Addison's disease [0]

2 ) bulimia nervosa [100]

3 ) diuretic abuse [0]

4 ) syndrome of inappropriate antidiuretic hormone secretion [0]

5 ) water intoxication [0]

Comments:

This patient is likely to have Bulimia young girl with a likely low body mass contributing to the lowurea, vomiting contributing to the hypokalaemia/hyponatraemia. Her urine sodium is appropriately low

and due to a relative dehydration she has appropriately concentrated urine. This is not Addisonsdiseaseas urine sodium would be high with high urea and likely high potassium. Similarly it is notSIADH due to the low urine sodium. Diuretic abuse would cause high urine sodium. Water intoxication

would produce a dilute urine.

Which one of the following statements applies to congenital adrenal hyperplasia:
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Endocrinology 18


1 ) It always presents shortly after birth [0]

2 ) Boys more commonly present at an earlier age than girls [0]

3 ) It is most frequently caused by 11 beta hydroxylase deficiency [0]

4 ) It is commonly associated with genital pigmentation [100]

5 ) Hypotension is invariably present. [0]

Comments:Congenital adrenal hyperplasia may present in teenagers with oligo/amenorrhoea andhirsuitism without significant virilisation and is termed late onset CAH. Girls present earlierbecause of virilisation and ambiguous genitalia, boys may present with precocious puberty. Itis most commonly caused by 21 hydroxylase deficiency and genital pigmentation is due tohigh circulating ACTH. 11 beta hydroxylase deficiency can cause virilisation with hypertension.

A six year old is admitted unconscious. His breath smells of Acetone. Blood gas estimation ispH 7.05, pCO2 24mmhg, standard bicarbonate 12mmol/l, blood glucose 47mmol/l. Which ofthe following statements are correct?


1 ) urea is likely to be low [0]

2 ) He has a respiratory acidosis [0]

3 ) He should be treated with subcutaneous insulin [0]

4 ) He has a metabolic acidosis [100]

5 ) He should be treated with 5% Dextrose. [0]

Comments:As a result of osmotic diuresis and natriuresis mediated by glucose he will be dehydrated andsodium depleted. This will raise blood urea.PCO2 and serum bicarbonate are low and this isconsistent with metabolic acidosis and respiratory compensation. In respiratory acidosis the

PCO2 would be high and bicarbonate levels would be higher to effect a metaboliccompensation. In view of the fact that he has diabetic ketoacidosis, treatment with insulinshould be commenced. Volume replacement with 0.9% saline must be adequate, howeverovervigorous rehydration could precipitate cerebral oedema.

In the treatment of Congenital Adrenal Hyperplasia, which of the following statements iscorrect?



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Endocrinology 19

1 ) Hydrocortisone may be administered once daily [0]

2 ) Preferred treatment in children is prednisone [0]

3 )Efficacy of treatment is best monitored by 17-OH progesterone andandrostenedione levels

[100]

4 ) Renin activity levels are of no clinical use in treatment monitoring [0]

5 ) Hypotension, hyperkalaemia and hyperreninaemia suggest that the dose ofmineralocorticoid should be reduced [0]

Comments:

In the treatment of CAH the lowest dose of glucocorticoid that suppresses(not totally) Adrenalandrogens, whilst maintaining normal growth and weight gain is the optimum dose ofglucocorticoid replacement.Renin activity levels can be used to monitor adequacy of mineralocorticoid and sodiumreplacement. Hydrocortisone has a relatively short half-life and must therefore be administeredtwice daily, whilst the preferred mode of glucocorticoid replacement in children ishydrocortisone as it minimises growth suppression.Over treatment with mineralocorticoids leads to hypertension, suppressed plasma rennin

activity and possibly growth retardation.

Which one of the following statements is correct:


1 ) Dyshormonogenesis is the commonest cause of congenital hypothyroidism [0]

2 )In patients with short stature (height below the 3rd centile) one should alwaysscreen for growth hormone efficiency

[0]

3 ) Congenital adrenal hyperplasia is a cause of ambiguous genitalia in the newborn [100]

4 ) Children with diabetes mellitus always require treatment with insulin [0]

5 ) Onset of puberty is usually earlier in boys than in girls [0]

Comments:The commonest causes of congenital hypothyroidism are thyroid aplasia/hypoplasia or ectopicthyroid gland. Short stature may be the consequence of multiple factors and Growth hormonedeficiency is identified in a minority of patients. Growth velocity, parental height, intercurrentillnesses and use of drugs such as steroids may be more relevant. In females with congenitaladrenal hyperplasia, excessive adrenal androgens result in virilisation and ambiguousgenitalia. The incidence of type 2 diabetes in children is rising, and children may be treatedwith weight loss/diet and or metformin. Also in the condition known as MODY (maturity onsetdiabetes of the young, autosomal dominant, defective insulin secretion) oral hypoglycaemicsare used initially. The onset of puberty is delayed by approximately 2 years in males, whencompared to females.

A 16 year old female presents with a six month history of excessive weight gain andweakness. On examination she had central obesity with abdominal striae, a blood pressure of178/96 mmHg and proximal muscle weakness. Urinalysis showed glucose ++. What is themost appropriate initial investigation for this patient?


1 ) 9am plasma cortisol concentration [0]


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Endocrinology 20

2 ) 24 hour urinary free cortisol concentration [100]

3 ) ACTH concentration [0]

4 ) a 1mg overnight dexamethasone suppression test [0]

5 ) a short synacthen test [0]

Comments:This patient is likely to have Cushings syndrome. Its a difficult choice between overnightdexamethasone suppression test and the urine free cortisol estimation but on balance, thesimplest test would be Urine free cortisol assessment. 9am cortisol and ACTH concentrationswill not confirm the diagnosis. A short synacthen test is used to confirm hypoadrenalism.

Leptin


1 ) Is synthesised in the hypothalamus [0]

2 ) Reduces Basal metabolic rate [0]

3 ) Acts upon the adipocyte [0]

4 ) Produces satiety [100]

5 ) Plasma concentrations correlate directly with lean body mass. [0]

Comments:Leptin is synthesised within the adipocyte and plasma concentrations are directly related toadipocyte (fat) mass. It acts on centres within the hypothalamus to produce satiety.

Side effects of recombinant human growth hormone therapy include:


1 ) Proliferative retinopathy [0]

2 ) Aplastic anaemia [0]3 ) Leukaemia [0]

4 ) Creutzfeldt-Jacob disease [0]

5 ) Benign Intracranial hypertension [100]

Comments:Unlike the old pituitary derived GH, rhGH is not associated with CJD as it is manufactured byrecombinant techniques. rhGH therapy has been associated with BIH probably due to the fluidretention associated with GH therapy.

A girl aged 5 years attending normal school presents to the outpatient clinic with bilateralenlargement of the breasts. Bone age is 5.8 years and height is on the 90th centile.

There has been no vaginal bleeding:

Which of the following is correct:


1 ) The diagnosis is unlikely to be precocious puberty [100]

2 ) It is desirable to check her karyotype in making a diagnosis [0]


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Endocrinology 21

3 ) Lateral skull X-ray should be requested [0]

4 ) Menarche will likely take place in 3 years [0]

5 ) She will need to be treated with Clomiphene [0]

Comments:

The diagnosis is unlikely to be precocious puberty as elevated gonadal steroid levels increaseheight velocity and the rate of skeletal maturation as well causing feminisation and breastdevelopment.

The condition is more suggestive of premature thelarche. Karyotypic anomalies are notrelevant. If central (LHRH dependent) precocious puberty is suspected then MRI would be ofvalue rather than cranial ultrasound to identify hypothalamic lesions and other CNS lesions.

However pelvic ultrasound showing normal uterine volume is the most sensitive discriminatorbetween premature thelarche and true precocious puberty. Puberty and menarche should takeplace at the normally expected timing( 11-13y).

LHRH agonists are used in the treatment of precocious puberty of all types and notclomiphene, an estrogen antagonist.

A genotypic male (XY) infant is born with feminised external genitalia. The testes are retainedwithin the abdomen and the internal reproductive tracts show a normal male phenotype. Whichof the following abnormalities would account for this abnormal development?


1 ) Complete androgen insensitivity [0]

2 ) 5 alpha-reductase deficiency [100]

3 ) 17alpha-hydroxylase deficiency [0]

4 ) Sertoli-only syndrome [0]5 ) Testicular dysgenesis [0]

Comments:The differentiation of the Wolffian ducts into normal male internal reproductive tract requirestestosterone but not dihydrotestsosterone. However, the differentiation of the external genitaliainto the male reproductive system does require DHT. Absence of 5 alpha reductase in thelatter will result in feminisation. Untreated patients are phenotypically female often present atpuberty with virilisation a consequence of testosterone surges. Treatment depends upon DHTtherapy.

Which of the following statements applies to congenital hypothyroidism.


1 ) Cannot be diagnosed clinically before 3 months of age [0]

2 ) May be associated with an ectopic thyroid gland [100]

3 ) Thyroxine may be discontinued after a period of treatment. [0]

4 ) Can present in the newborn period with haemolytic jaundice. [0]

5 ) If undiagnosed causes short stature but with a normal bone age. [0]


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Endocrinology 22

Comments:Patients with congenital hypothyroidism may exhibit non-specific clinical features e.g. jaundiceand poor feeding however macroglossia is a fairly specific clinical finding aiding diagnosis. Thecommonest causes of congenital hypothyroidism are an absent or ectopic gland. The need forthyroxine is life long. The hyperbilirubinaemia is conjugated and haemolytic jaundice wouldnot occur. Short stature and delayed bone age occur.

A 17 year-old female is referred following a visit to the dentist where marked erosion of herteeth was noted. She was entirely asymptomatic and her only medication was the oralcontraceptive pill. On examination her blood pressure was 110/70 mmHg and her body massindex was 21.5 kg/m

2(18 - 25).

Investigations

sodium 135 mmol/l

potassium 2.1 mmol/l

bicarbonate 42 mmol/l

urea 2.6 mmol/L

corrected calcium 2.08 mmol/

alkaline phosphatase 201 iu/l (50-110)



1 ) Bulimia nervosa [0]

2 ) Conn's syndrome [0]

3 ) Laxative abuse [0]

4 ) Pregnancy [0]

5 ) Primary hypoparathyroidism [100]

Comments:This patient has tooth erosion associated with hypokalaemic metabolic alkalosis andhypocalcaemia. This suggests a diagnosis of hypoparathyroidism. Conn's is unlikely in thisage group, is not associated with tooth erosion and hypertension would be expected. Bulimialike laxative abuse would be associated with hypokalaemia but the hypocalcaemia with raisedalkaline phosphatase would not be expected. Early pregnancy would not fit this picture.

Which one of the following statements is correct concerning hyperglycaemia (non-ketotic) in anestablished diabetic child :


1 ) Is usually symptomatic [0]

2 ) Requires additional insulin immediately [0]

3 ) May be seen following an untreated hypoglycaemic convulsion [100]

4 ) Is a cause of recurrent urinary tract infections [0]

5 ) Should be treated by reducing the number of daily carbohydrate exchanges [0]

Comments:


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Endocrinology 23

Non-ketotic hyperglycaemia is usually asymptomatic, or less frequently mild symptoms suchas thirst and polyuria may develop. Additional stat doses of insulin may cause hypoglycaemialater>

Untreated hypoglycaemia may result in delayed hyperglycaemia through the influence of

counter-regulatory hormones e.g catecholamines and growth hormone, which will raise bloodglucose.

Recurrent urinary infections are not associated, however furuncles are. The condition shouldbe treated according to the cause. For example if the hyperglycaemia is reactive and precededby severe hypoglycaemia, insulin dosage may have to be reduced and carbohydratesincreased.

A 15-year-old girl complained of anxiety and excessive sweating. She was not taking anymedication.

Investigations showed:

TSH concentration 0.9 mU/L (0.5-3.4)

free T4 concentration 16 pmol/L (10-18)

total T4 concentration 180 nmol/L (55-145)

free T3 concentration 8.2 pmol/L (3.5-10.5)

total T3 concentration 3.3 nmol/L (0.9-2.5)

These results are compatible with which one of the following diagnoses?


1 ) Factitious thyrotoxicosis [0]

2 ) Familial dysalbuminaemic hyperthyroxinaemia [0]

3 ) Pregnancy [100]

4 ) Sick euthyroid syndrome [0]

5 ) Thyrotoxicosis [0]

Comments:The symptom complex is intentionally misleading. The patient has a normal TSH and normal

free T3 and T4 concentrations, excluding thyrotoxicosisbut elevated Total concentrationssuggesting a rise in the binding globulins. This can occur in pregnancy. Sick euthyroidismwould be typically associated with low thyroid hormone concentrations.

A 17 year old female who is 16 weeks pregnant reports that her elder brother has vitamin Dreisistant rickets. What is the most likely mode of inheritance of this condition?

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Endocrinology 24

1 ) Autosomal dominant [0]

2 ) Autosomal dominant with incomplete penetrance [0]

3 ) Autosomal recessive [0]

4 ) X-linked dominant [100]

5 ) X-linked recessive [0]

Comments:

Vitamin D resistant rickets is inherited in an X-linked dominant manner. Therefore an affected female

will transmit the disease to 50% of her sons and 50% of her daughters. An affected male will transmit

the condition to all of his daughters but none of his sons. In this case as the mother is unaffected,

therefore there is no risk of the condition being passed to her unborn child.

A 13 year old girl is rushed into hospital, having become rapidly drowsy after running the 1500metres in the school atheletics competition. She has been on insulin for diabetes for 3 years.Her latest HbA1C is 7.8%.

On examination she responds to pain, and is pale and sweaty. Her temperature is 36.5C, RR12/min and HR 80/min. There are no focal neurological findings.



1 ) Child abuse [0]

2 ) Hepatic failure [0]

3 ) Hypoglycaemia [100]

4 ) Diabetic ketoacidosis [0]

5 ) Substance abuse [0]

Comments:

The history suggests tight diabetic control, with neurological deterioration following exercise.Hypoglycaemic coma is most likely, and the sweatiness and pallor are suggestive. The BM stixin this case was 1.2 mmol/l and she recovered rapidly with IV 10% dextrose 5 ml/kg.

A 17-year-old girl complains of feeling tired and lethargic for the last 6 months. She also hasgeneralized abdominal discomfort and constipation. She denies depression but herperformance at school has deteriorated this year. Examination shows a pale and thin youngwoman. Her blood pressure is 110/60 mmHg.

Hb 13.4 g/l

WBC 4.8 x 109

Platelet 290 x 109

ESR 37mm/hr

Na 131mM (135-144)

K 2.7mM (3.4-4.5)

Urea 3.0mM (3-7)

Creat 90mM (50 - 100)

Bicarbonate 35mM (20-28)


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Endocrinology 25

Alkaline phosphotase 90iu/l (50-110)

bilirubin 12 (0-17)

AST 30 iu/l (5-40)

Albumin 36g/l (33-44)

CXR normal

Which of the following is the most likely underlying diagnosis?


1 ) Cushings syndrome [0]

2 ) Conns syndrome [0]

3 ) Addisons disease [0]

4 ) Anorexia nervosa [100]

5 ) Phaechromocytoma [0]

Comments:

This patient has anorexia nervosa with self-induced vomiting, which would explain the low Na,K and alkalosis. Addisons disease causes hyponatraemia and hyperkalaemic acidosis, whilstCushings disease cause hypokalaemic alkalosis. The clinical presentation does not fit with thelatter. Conn's syndrome (adrenal adenoma) is associated with hypertension andhypokalaemia.

A 12 year old girl presents with anxiety and weight loss. She is noted to have a fine tremor anda pulse of 100 beat per minute. Thyroid function tests confirm thyrotoxicosis. Which one of thefollowing statements is true of thyrotoxicosis in children.


1 ) Is more common in males [0]

2 ) Is often associated with short stature [0]

3 ) Is usually not due to an auto-immune process [0]

4 ) Is treated in the first instance with anti-thyroid drugs such as Carbimazole [100]

5 ) Is usually associated with a high TSH level [0]

Comments:Thyrotoxicosis has a female preponderance in all age groups. Thyrotoxicosis in early life maycause delayed sexual maturation, although physical development is normal and skeletalgrowth may be accelerated. Thyrotoxicosis in this age group is mostly due to graves disease.

Anti thyroid drugs, are used initially and relapses can be treated with drugs or surgery.Radioactive iodine is generally not administered. TSH is suppressed.

Which of the following statements concerning Congenital adrenal hyperplasia due to 21hydroxylase deficiency is correct:


1 ) It causes testicular enlargement [0]


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Endocrinology 26

2 ) It results in delayed fusion of epiphyses [0]

3 ) There is increased aldosterone secretion [0]

4 ) It has an autosomal recessive inheritance [100]

5 ) It is more easily diagnosed in boys than girls [0]

Comments:The condition causes virilisation in the female (male secondary sexual characteristics e.g.clitoromegaly, ambiguous genitalia) and in males sexual development may be entirely normalor precocious puberty develops. Delayed epiphyseal fusion is not a feature. Aldosteronedeficiency causes salt wasting in this condition. The disease has an autosomal recessiveinheritance. The disease is far more easily diagnosed in females who develop abnormalgenitalia, than males who may have no clinical signs.

Which one of the following is inherited in an autosomal dominant fashion:


1 ) Neurofibromatosis [100]

2 ) Cystic fibrosis [0]

3 ) Prader-Willi syndrome [0]

4 ) Beta-Thalassaemia [0]

5 ) Downs syndrome [0]

Comments:

Neurofibromatosis is a single gene autosomal dominant disorder. Beta Thalassaemia is recessivelyinherited. One copy of the abnormal gene is termed thalassaemia minorand if there are 2 copies of theabnormal gene the condition, which develops, is thalassaemia major. Prader Willi syndrome is a

chromosomal disorder characterised by insatiable appetite, hyperglycaemia and short stature. Downssyndrome is a chromosomal disorder.

A child is diagnosed with congenital adrenal hyperplasia. Which of the following statements correctlyapplies to his condition.


1 ) It has an X-linked inheritance [0]

2 ) There is over-production of cortisol [0]

3 ) Hypokalaemia occurs. [0]

4 ) Undescended testes is associated. [0]

5 ) If untreated he may be infertile later. [100]

Comments:

Congenital Adrenal Hyperplasia has an autosomal recessive inheritance. Failure to synthesise cortisol bythe adrenals leads to a feedback activation of ACTH production by the pituitary. Potassium retentionoccurs as a consequence of aldosterone deficiency. Undescended testes are not associated, howevertesticular adrenal rest tumours are associated. Undertreated patients may be infertile later due to thepresence of high circulating androgens.


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A male has pectus excavatum. Which one of the following findings would point to a diagnosis of Marfanssyndrome.


1 ) Mental retardation [0]

2 ) Osteoporosis [0]

3 ) Short stature [0]

4 ) History of peripheral arterial occlusion [0]

5 ) Echocardiogram shows ascending aortic aneurysm [100]

Comments:

Marfans syndrome is autosomal dominant and shares some features in common with homocystinuria(scoliosis, tall stature, lens subluxation), but mental retardation, osteoporosis and arterio/venousthrombosis are features of the latter condition.

A short dysmorphic 12 year old child presents to you. Which one of the following would lead you tosuspect she may have Turners syndrome.


1 ) Mental retardation [0]

2 ) Cyanotic heart disease [0]

3 ) Primary amenorrhoea [100]

4 ) Accelerated bone age [0]

5 ) Bilateral clinodactyly [0]

Comments:

Mental retardation is not a feature. Bicuspid aortic valve and coarctation rather than cyanotic heartdisease are associated. Primary amenorrhoea occurs due to gonadal dysgenesis. Bone age may bedelayed. Clinodactyly is not a feature.

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