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Question 1
Incorrect
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A 26-year-old woman is 24 weeks pregnant had a recent ultrasound that shows the foetus large for dates.
She has an oral glucose tolerance test (OGTT) which was requested due to a combination of her Asian ethnicity and background of obesity.
The following results are obtained:
Time (hours) Blood glucose (mmol/l)
0 9.2
2 14.2
What is the most appropriate management?Your Answer: Start metformin
Correct Answer: Start insulin
Explanation:Insulin remains the standard of care for the treatment of uncontrolled gestational diabetes. Tight control maintained in the first trimester and throughout pregnancy plays a vital role in decreasing poor fetal outcomes, including structural anomalies, macrosomia, hypoglycaemia of the new-born, adolescent and adult obesity, and diabetes.
The baby is already large for dates so nutritional therapy can not be used alone. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 2
Incorrect
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A 26-year-old woman presents to a reproductive endocrinology clinic with a history of not being able to conceive after 2 years of using no contraception. Polycystic ovarian syndrome maybe her diagnosis.
Which of the following is most likely to be associated with this condition?Your Answer: Low levels of circulating insulin
Correct Answer: Elevated LH/FSH ratio
Explanation:In patients with polycystic ovarian syndrome (PCOS), FSH levels are within the reference range or low. Luteinizing hormone (LH) levels are elevated for Tanner stage, sex, and age. The LH-to-FSH ratio is usually greater than 3.
Women with PCOS have abnormalities in the metabolism of androgens and oestrogen and in the control of androgen production. PCOS can result from abnormal function of the hypothalamic-pituitary-ovarian (HPO) axis.
The major features of PCOS include menstrual dysfunction, anovulation, and signs of hyperandrogenism. Other signs and symptoms of PCOS may include the following:
– Hirsutism
– Infertility
– Obesity and metabolic syndrome
– Diabetes
– Obstructive sleep apnoeaAndrogen excess can be tested by measuring total and free testosterone levels or a free androgen index. An elevated free testosterone level is a sensitive indicator of androgen excess. Other androgens, such as dehydroepiandrosterone sulphate (DHEA-S), may be normal or slightly above the normal range in patients with polycystic ovarian syndrome (PCOS). Levels of sex hormone-binding globulin (SHBG) are usually low in patients with PCOS.
Some women with PCOS have insulin resistance and an abnormal lipid profile (cholesterol >200 mg/dL; LDL >160 mg/dL). Approximately one-third of women with PCOS who are overweight have impaired glucose tolerance or type 2 diabetes mellitus by 30 years of age.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 3
Correct
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A 48-year-old female presented in the emergency department with complaints of increased thirst, confusion and drowsiness. When taking her history it was found that she was treated successfully for breast malignancy 2 years ago. Which of the following abnormalities is most likely responsible for these symptoms?
Your Answer: Hypercalcemia
Explanation:Treated breast malignancy is pointing towards hypercalcemia as it is very common in patients of CA. The symptoms of hypercalcemia are increased thirst, drowsiness and confusion.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 4
Correct
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A 35-year-old female admitted with heat intolerance, neck pain, palpitations and recent onset weight loss despite increased appetite. Which of the following is most likely to be associated with diagnosis of thyroiditis associated with viral infection?
Your Answer: Reduced uptake on thyroid isotope scan
Explanation:Subacute thyroiditis (De Quervain’s thyroiditis) is a self-limiting thyroid condition presenting with three clinical courses of hyperthyroidism, hypothyroidism, and return to normal thyroid function. In subacute thyroiditis serum thyroglobulin (TG) levels are elevated. ESR is usually greater than 50 mm/h, often exceeding 100 mm/h. Radio-iodine uptake is low or nil. Antithyroperoxidase antibodies are associated with autoimmune thyroiditis
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 5
Correct
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A 55-year-old woman complains of weight gain, hoarseness of voice, constipation, and muscle weakness 1 month after undergoing thyroid surgery. On examination, her face is puffy. Which of the following is the most likely diagnosis?
Your Answer: Hypothyroidism
Explanation:All the symptoms this patient is suffering from are the classic features of a hypothyroid state.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 6
Incorrect
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Regarding the pathophysiology of diabetes mellitus, which of the following is true?
Your Answer: Patients with type 1 diabetes mellitus are rarely HLA-DR4 positive
Correct Answer: Concordance between identical twins is higher in type 2 diabetes mellitus than type 1
Explanation:Type 1 diabetes is a chronic illness characterized by the body’s inability to produce insulin due to the autoimmune destruction of the beta cells in the pancreas. Approximately 95% of patients with type 1 DM have either HLA-DR3 or HLA-DR4. Although the genetic aspect of type 1 DM is complex, with multiple genes involved, there is a high sibling relative risk. Whereas dizygotic twins have a 5-6% concordance rate for type 1 DM, monozygotic twins will share this diagnosis more than 50% of the time by the age of 40 years.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 7
Correct
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An 18-year-old woman in her 30th week of pregnancy is brought to the hospital in altered sensorium. She is taking slow, shallow breaths and her breath has a fruity smell. An arterial blood gas (ABG) shows the presence of ketones. What is the most probable diagnosis?
Your Answer: Diabetic Ketoacidosis (DKA)
Explanation:This a case of gestational diabetes presenting with DKA. It is a serious case that requires immediate intervention. Pregnant diabetics tend to develop DKA on a lower serum glucose level than non-pregnant diabetics. The shortness of breath is a trial to wash the excess CO2 to compensate for the metabolic acidosis seen in the ABG. The fruity smell is acetone excreted through the lungs. The main treatment of this case is proper fluid management and insulin infusion.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 8
Correct
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A 70-year-old man presents to the emergency department acutely unwell. He is shocked, drowsy and confused.
He is known to be type-2 diabetic maintained on metformin.
Blood tests reveal a metabolic acidosis with an anion gap of 24 mmol/l. Ketones are not significantly elevated and random blood glucose was 8.7 mmol/l.
What is the mainstay of treatment for this condition?Your Answer: Rehydration
Explanation:Lactic acidosis is occasionally responsible for metabolic acidosis in diabetics. It may occur in the presence of normal blood levels of the ketone bodies, and such cases are often described as having non-ketotic diabetic acidosis.
It is most commonly associated with tissue hypoperfusion and states of acute circulatory failure.
Appropriate measures include treatment of shock, restoration of circulating fluid volume, improved cardiac function, identification of sepsis source, early antimicrobial intervention, and resection of any potential ischemic regions. Reassessment of lactate levels for clearance assists ongoing medical management. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 9
Correct
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A 35-year-old female had an oral glucose tolerance test. Her oral glucose test after 2 hrs was 10mml/l. What is the result of her test?
Your Answer: Impaired glucose tolerance
Explanation:Impaired glucose tolerance is a pre-diabetic state of hyperglycaemia that is associated with insulin resistance and increased risk of cardiovascular pathology. To diagnose impaired glucose tolerance, the OGTT value after 2 hrs should be 140-199mg/dl (7.7 – 11.0 mmol/l). Impaired fasting glucose is diagnosed as fasting blood sugar between 100 mg/dl to 125 mg/dl.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 10
Correct
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A 25-year-old woman is found to have a blood pressure of 170/100 mmHg during a routine medical check. She is otherwise well and her physical examination is unremarkable.
Blood tests show:
Na+ 140 mmol/l
K+ 2.6 mmol/l
Bicarbonate 31 mmol/l
Urea 3.4 mmol/l
Creatinine 77 µmol/l
Which one of the following investigations is most likely to be diagnostic?Your Answer: Renin:aldosterone ratio
Explanation:Primary aldosteronism now is considered one of the more common causes of secondary hypertension (HTN).
Individuals with primary aldosteronism may present with hypokalaemia metabolic alkalosis; however, as many as 38% of patients with primary aldosteronism may be normokalaemia at presentation.
Routine laboratory studies can show hypernatremia, hypokalaemia, and metabolic alkalosis resulting from the action of aldosterone on the renal distal convoluted tubule (DCT) (i.e., enhancing sodium reabsorption and potassium and hydrogen ion excretion).
Plasma aldosterone/plasma renin activity ratio is used for screening because it is fairly constant over many physiologic conditions.The patient is clinically free, so Cushing diseases can be exclude.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 11
Correct
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A 46-year-old woman was referred to the endocrinology department with hypercalcemia and raised parathyroid hormone levels. Her blood tests are highly suggestive of primary hyperparathyroidism.
She has type 2 diabetes controlled by metformin alone. Her albumin-adjusted serum calcium level is 3.5 mmol/litre.
Which of the following is the most important reason for her referral?Your Answer: Albumin-adjusted serum calcium level of 3.5 mmol/litre
Explanation:Indications for surgery for the treatment of primary hyperparathyroidism:
1. Symptoms of hypercalcaemia such as thirst, frequent or excessive urination, or constipation
2. End-organ disease (renal stones, fragility fractures or osteoporosis)
3. An albumin-adjusted serum calcium level of 2.85 mmol/litre or above. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 12
Incorrect
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Which of the following is most consistent with small cell lung cancer?
Your Answer: hypercalcemia is commonly seen
Correct Answer: hypertrophic pulmonary osteoarthropathy is rarely seen
Explanation:The clinical manifestations of Small cell lung cancer (SCLC) can result from local tumour growth, intrathoracic spread, distant spread, and/or paraneoplastic syndromes.
Hypertrophic pulmonary osteoarthropathy (HPO) is a rare paraneoplastic syndrome that is frequently associated with lung cancer; however, the incidence of clinically apparent HPO is not well known.
SIADH is present in 15% of cases and most commonly seen.
Although hypercalcaemia is frequently associated with malignancy, it is very rare in small cell lung cancer despite the high incidence of lytic bone metastases.
Ectopic Cushing’s syndrome in SCLC does not usually exhibit the classic signs of Cushing’s syndrome and Cushing’s syndrome could also appear during effective chemotherapy.
Chemotherapy is the treatment of choice in SCLC. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 13
Incorrect
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A 19-year-old male has gone to his local doctor's surgery complaining of weight loss, an increased thirst, and urinating more frequently. His father, grandfather, and both of his sisters have all been diagnosed with DM. What type of DM does this patient most likely suffer from?
Your Answer: IDDM
Correct Answer: MODY
Explanation:The key features of MODY are: being diagnosed with DM under the age of 15, having a parent with DM, and DM in two or more generations of the family.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 14
Incorrect
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A 28-year-old woman is evaluated in the endocrinology clinic for increased urine output. She weighs 60 kg and has a 24-hour urine output of 3500 ml. Her basal urine osmolality is 210 mOsm/kg.
She undergoes a fluid deprivation test and her urine osmolality after fluid deprivation (loss of weight 3 kg) is 350 mOsm/kg. Subsequent injection of subcutaneous DDAVP (desmopressin acetate) did not result in a further significant rise of urine osmolality after 2 hours (355 mOsm/kg).
Which of the following is the most likely diagnosis?Your Answer: Nephrogenic diabetes insipidus
Correct Answer: Primary polydipsia
Explanation:In central and nephrogenic diabetes insipidus (DI), urinary osmolality will be less than 300 mOsm/kg after water deprivation. After the administration of ADH, the osmolality will rise to more than 750 mOsm/kg in central DI but will not rise at all in nephrogenic DI. In primary polydipsia, urinary osmolality be above 750 mOsm/kg after water deprivation. A urinary osmolality that is 300-750 mOsm/kg after water deprivation and remains below 750 mOsm/kg after administration of ADH may be seen in partial central DI, partial nephrogenic DI, and primary polydipsia.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 15
Correct
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A 77-year-old woman is admitted in an unconscious state. On examination in casualty, her temperature is 33 °C and she was in left ventricular failure.
Her blood glucose level is 5.7 mmol/l and random cortisol is elevated. Free T4 is 4.4 pmol/l.
A CT scan of her brain reveals no focal lesion and a cursory assessment reveals no gross focal neurology.
Which diagnosis fits best with this woman's clinical picture?Your Answer: Profound hypothyroidism
Explanation:Elderly patients with severe hypothyroidism often present with variable symptoms that may be masked or potentiated by co-morbid conditions. Characteristic symptoms may include fatigue, weight gain, cold intolerance, hoarseness, constipation, and myalgias. Neurologic symptoms may include ataxia, depression, and mental status changes ranging from mild confusion to overt dementia.
Clinical findings that may raise suspicion of thyroid hormone deficiency include hypothermia, bradycardia, goitrous enlargement of the thyroid, cool dry skin, myxoedema, delayed relaxation of deep tendon reflexes, a pericardial or abdominal effusion, hyponatremia, and hypercholesterolemia.The patient has a greatly reduced free T4 concentration, is hypothermic, unconscious and has evidence of associated heart failure. All of those support the diagnosis of profound hypothyroidism.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 16
Correct
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A 42-year-old male with long history of diabetes is complaining of a red-hot tender lump near his anus. What is the most possible diagnosis?
Your Answer: Abscess
Explanation:A diabetic patient is a patient with depressed immunity. It is not uncommon to develop abscesses. Diabetic patients have a defected cellular innate immunity. On the other hand, bacteria become much more virulent in a high glucose environment in the interstitium.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 17
Correct
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A 25-year-old woman with type-1 diabetes mellitus attends for her routine review and says she is keen on becoming pregnant.
Which of the following is most likely to make you ask her to defer pregnancy at this stage?Your Answer: Hb A1C 9.4%
Explanation:Pregnancies affected by T1DM are at increased risk for preterm delivery, preeclampsia, macrosomia, shoulder dystocia, intrauterine fetal demise, fetal growth restriction, cardiac and renal malformations, in addition to rare neural conditions such as sacral agenesis.
Successful management of pregnancy in a T1DM patient begins before conception. Research indicates that the implementation of preconception counselling, emphasizing strict glycaemic control before and throughout pregnancy, reduces the rate of perinatal mortality and malformations.
The 2008 bulletin from the National Institute for Health and Clinical Excellence recommends that preconception counselling be offered to all patients with diabetes. Physicians are advised to guide patients on achieving personalized glycaemic control goals, increasing the frequency of glucose monitoring, reducing their HbA1C levels, and recommend avoiding pregnancy if the said level is > 10%.
Other sources suggest deferring pregnancy until HbA1C levels are > 8%, as this margin is associated with better outcomes. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 18
Incorrect
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A 40-year-old man is referred by his general practitioner. He has a family history of premature cardiovascular disease.
Cholesterol testing reveals triglyceride levels of 4.2 mmol/l and a high-density lipoprotein (HDL) level of 0.8 mmol/l.
You advise him to start fibrate therapy.
Which of the following best describes the mode of action for fibrates?Your Answer: They are inhibitors of CETP cholesterol ester transferase protein activity
Correct Answer: They are inhibitors of lipoprotein lipase activity and increase HDL synthesis
Explanation:Treatment with fibrates, a widely used class of lipid-modifying agents, results in a substantial decrease in plasma triglycerides and is usually associated with a moderate decrease in LDL cholesterol and an increase in HDL cholesterol concentrations.
Evidence from studies is available to implicate 5 major mechanisms underlying the above-mentioned modulation of lipoprotein phenotypes by fibrates:
1. Induction of lipoprotein lipolysis.
2. Induction of hepatic fatty acid (FA) uptake and reduction of hepatic triglyceride production.
3. Increased removal of LDL particles. Fibrate treatment results in the formation of LDL with a higher affinity for the LDL receptor, which is thus catabolized more rapidly.
4. Reduction in neutral lipid (cholesteryl ester and triglyceride) exchange between VLDL and HDL may result from decreased plasma levels of TRL.
5. Increase in HDL production and stimulation of reverse cholesterol transport. Fibrates increase the production of apoA-I and apoA-II in the liver, which may contribute to the increase of plasma HDL concentrations and a more efficient reverse cholesterol transport. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 19
Incorrect
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A 28-year-old manual worker had stepped on a rusty nail. He says he received tetanus toxoid 8 years ago. What should be done for him now?
Your Answer: Human immunoglobulin and full course of tetanus vaccine
Correct Answer: Human immunoglobulin only
Explanation:Only immunoglobulins are required, as he is already immunized.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 20
Incorrect
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A 25-year-old woman comes to the endocrine clinic for her regular follow up. She has hypertension, controlled by a combination of Ramipril and indapamide and was diagnosed with 11-beta hydroxylase deficiency since birth when she was found to have clitoromegaly.
Which of the following is most likely to be elevated?Your Answer: 17-OH pregnenolone
Correct Answer: 11-Deoxycortisol
Explanation:11-beta hydroxylase is stimulated by ACTH and responsible for conversion of 11-deoxycortisol to cortisol and deoxycorticosterone to corticosterone.
In 11-beta hydroxylase deficiency, the previously mentioned conversions are partially blocked, leading to:
– Increased levels of ACTH
– Accumulation of 11-deoxycortisol (which has limited biological activity) and deoxycorticosterone (which has mineralocorticoid activity)
– Overproduction of adrenal androgens (DHEA, androstenedione, and testosterone) -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 21
Correct
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A 23-year-old man who works as a clerk presents for review. He is 6 feet 2 inches tall, with delayed puberty and infertility. On examination, he has small testes with scanty pubic hair.
Blood results are shown below:
Follicle-stimulating hormone (FSH) 40 U/l (1-7)
Testosterone 4 nmol/l(9-35)
What is the most probable diagnosis?Your Answer: 47XXY
Explanation:Klinefelter syndrome (KS), the most common human sex chromosome disorder 47,XXY. It is characterized by hypogonadism (micro-orchidism, oligospermia/azoospermia) and gynecomastia in late puberty. If Klinefelter syndrome is not diagnosed prenatally, a patient with 47,XXY karyotype may demonstrate various subtle, age-related clinical signs that would prompt diagnostic testing. These include the following:
Infants: Hypospadias, small phallus, cryptorchidism.
Toddlers: Developmental delay (especially expressive language skills), hypotonia.
Older boys and adolescent males: Tall stature; delayed or incomplete pubertal development with eunuchoid body habitus; gynecomastia; small, firm testes; sparse body hair.From childhood with progression to early puberty, the pituitary-gonadal function observed is within normal limits for 47,XXY males.
At mid puberty and later, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) concentrations rise to hyper-gonadotropic levels, inhibin B levels fall until they are undetectable, and testosterone levels are at low or low-normal levels after an initial increase.Fragile X syndrome, also termed Martin-Bell syndrome or marker X syndrome, is the most common cause of inherited mental retardation, intellectual disability, and autism.
However, the patient here does not have any mental disabilities as he already works as a clerk, and that too would make Down’s Syndrome less likely.Classic Kallmann syndrome (KS) and idiopathic hypogonadotropic hypogonadism (IHH) are rare genetic conditions that encompass the spectrum of isolated hypogonadotropic hypogonadism. Most patients have gonadotropin-releasing hormone (GnRH) deficiency, as suggested by their response to pulsatile GnRH therapy. Hypothalamic-pituitary function is otherwise normal in most patients, and hypothalamic-pituitary imaging reveals no space-occupying lesions. By definition, either anosmia or severe hyposmia is present in patients with Kallmann syndrome, in contrast to patients with idiopathic hypogonadotropic hypogonadism, whose sense of smell is normal.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 22
Correct
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In a patient with type-1 diabetes mellitus, which cells when affected, lead to insulin deficiency?
Your Answer: B cells of the pancreatic islets
Explanation:Insulin is produced by the beta-cells in the islets of Langerhans in the pancreas while Glucagon is secreted from the alpha cells of the pancreatic islets of Langerhans.
Type 1 diabetes mellitus is the culmination of lymphocytic infiltration and destruction of the beta cells of the islets of Langerhans in the pancreas. As beta-cell mass declines, insulin secretion decreases until the available insulin is no longer adequate to maintain normal blood glucose levels. After 80-90% of the beta cells are destroyed, hyperglycaemia develops and diabetes may be diagnosed. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 23
Correct
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A 50-year-old man is referred with impotence. He has a history of angina, hypertension and type 2 diabetes.
Which one of the following drugs that he takes is a contraindication to him being able to receive sildenafil?Your Answer: Isosorbide mononitrate
Explanation:Sildenafil administration to patients who are using organic nitrates, either regularly and/or intermittently, in any form is contraindicated.
Organic nitrates and nitric oxide (NO) donors exert their therapeutic effects on blood pressure and vascular smooth muscle by the same mechanism as endogenous NO via increasing cGMP concentrations. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 24
Correct
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A 55-year-old woman admitted to the hospital with her third urinary tract infection in as many months. She has type-2 diabetes and started Empagliflozin (a sodium glucose co-transporter 2 inhibitor) 4 months ago. You suspect recurrent urinary tract infections secondary to her empagliflozin.
Where is the main site of action of the drug?Your Answer: Early proximal convoluted tubule
Explanation:Selective sodium-glucose transporter-2 (SGLT2) is expressed in the proximal renal tubules and is responsible for the majority of the reabsorption of filtered glucose from the tubular lumen.
Empagliflozin; SGLT2 inhibitors reduce glucose reabsorption and lower the renal threshold for glucose, thereby increasing urinary glucose excretion, thus increasing the risk of urinary tract infections. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 25
Correct
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Which of the following allows for a diagnosis of diabetes mellitus?
Your Answer: Symptomatic patient with random glucose 12.0 mmol/L on one occasion
Explanation:Criteria for the diagnosis of diabetes
1. A1C >6.5%. The test should be performed in a laboratory using a method that is certified and standardized.*
OR
2. Fasting glucose >126 mg/dl (7.0 mmol/l). Fasting is defined as no caloric intake for at least 8 h.*
OR
3. 2-h plasma glucose >200 mg/dl (11.1 mmol/l) during an OGTT. The test should be performed as described by the World Health Organization, using a glucose load containing the equivalent of 75 g anhydrous glucose dissolved in water.*
OR
4. In a patient with classic symptoms of hyperglycaemia or hyperglycaemic crisis, a random plasma glucose >200 mg/dl (11.1 mmol/l).
*In the absence of unequivocal hyperglycaemia, criteria 1-3 should be confirmed by repeat testing. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 26
Correct
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A 17-year-old Jewish girl presents with primary amenorrhoea. On examination, she looks a little hirsute and has evidence of facial acne. She is within her predicted adult height and has normal breast and external genitalia development, however, there is excess hair over her lower abdomen and around her nipple area.
Investigations were as follows:
Hb 13.1 g/dl
WCC 8.6 x109/l
PLT 201 x109/l
Na+ 139 mmol/l
K+ 4.5 mmol/l
Creatinine 110 µmol/l
17-OH progesterone 1.4 times the upper limit of normal
Pelvic ultrasound: bilateral ovaries and uterus visualised.
Which of the following is the most likely diagnosis?Your Answer: Non-classical congenital adrenal hyperplasia
Explanation:Mild deficiencies of 21-hydroxylase or 3-beta-hydroxysteroid dehydrogenase activity may present in adolescence or adulthood with oligomenorrhea, hirsutism, and/or infertility. This is termed nonclassical adrenal hyperplasia.
Late-onset or nonclassical congenital adrenal hyperplasia (NCAH) due to 21-hydroxylase deficiency is one of the most common autosomal recessive disorders. Reported prevalence ranges from 1 in 30 to 1 in 1000. Affected individuals typically present due to signs and symptoms of androgen excess.
Treatment needs to be directed toward the symptoms. Goals of treatment include normal linear growth velocity, a normal rate of skeletal maturation, ‘on-time’ puberty, regular menstrual cycles, prevention of or limited progression of hirsutism and acne, and fertility. Treatment needs to be individualized and should not be initiated merely to decrease abnormally elevated hormone concentrations.
Normal Ultrasound rules out Turner’s syndrome. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 27
Correct
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A young woman is concerned that she has put on weight since she was a medical student, as she now no longer finds time to exercise. She decides to try various weight loss tablets temporarily.
After 2 months, she is successfully losing weight but also has trouble with increased stool frequency, difficulty in climbing stairs and getting up out of chairs. However, she has no problems walking on the flat.
She also has difficulty in sleeping at the moment but puts that down to the increased frequency of headaches for the past 2 months.
Which one of the following is the most likely cause of her weakness?Your Answer: She is abusing thyroxine tablets
Explanation:Exogenous thyroid hormone use has been associated with episodes of thyroid storm as well as thyrotoxic periodic paralysis.
It presents with marked proximal muscle weakness in both upper and lower limbs, hypokalaemia and signs of hyperthyroidism.
Hyperthyroidism generally presents with tachycardia, hypertension, hyperthermia, and cardiac arrhythmiasLaxatives and diuretics can result in electrolyte abnormalities.
Medical complications associated with laxatives include chronic diarrhoea which disrupts the normal stool electrolyte concentrations that then leads to serum electrolyte shifts; acutely, hypokalaemia is most typically seen. The large intestine suffers nerve damage from the chronic laxative use that renders it unable to function properly. The normal peristalsis and conduction are affected; the disorder is thought to be secondary to a degeneration of Auerbach’s Plexi. However, it does not cause muscle weakness.Insulin tends to cause weight gain, not weight loss.
Metformin does not cause muscle weakness but can cause headaches. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 28
Incorrect
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Which of the following is most consistent with achondroplasia?
Your Answer: Increased liability to pathological fractures
Correct Answer: May be diagnosed radiologically at birth
Explanation:Achondroplasia is the most common type of short-limb disproportionate dwarfism. A single gene mapped to the short arm of chromosome 4 (band 4p16.3) is responsible for achondroplasia and is transmitted as an autosomal dominant trait. All people with achondroplasia have a short stature.
Characteristic features of achondroplasia include an average-size trunk, short arms and legs with particularly short upper arms and thighs, limited range of motion at the elbows, and an enlarged head (macrocephaly) with a prominent forehead. Fingers are typically short and the ring finger and middle finger may diverge, giving the hand a three-pronged (trident) appearance. People with achondroplasia are generally of normal intelligence.
Examination of the infant after birth shows increased front-to-back head size. There may be signs of hydrocephalus. It may be diagnosed radiographically at birth, or becomes obvious within the first year with disparity between a large skull, normal trunk length and short limbs. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 29
Correct
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A 40-year-old man presents with a history of carpal tunnel syndrome and osteoarthritis of his weight-bearing joints. He has recently begun to suffer from symptoms of sleep apnoea.
On examination, he has a prominent jawline and macroglossia. His BP is elevated at 155/95 mmHg and there is peripheral visual field loss.
Which of the following is true?Your Answer: Pegvisomant can be used where IGF-1 is not normalised post surgery
Explanation:The patient has Acromegaly.
Acromegaly is a chronic disorder characterised by growth hormone (GH) hypersecretion, predominantly caused by a pituitary adenoma.Random GH level testing is not recommended for diagnosis given the pulsatile nature of secretion. Stress, physical exercise, acute critical illness and fasting state can cause a physiological higher peak in GH secretion.
Pegvisomant is a US Food and Drug Administration-approved treatment for use after surgery. In a global non-interventional safety surveillance study, pegvisomant normalised IGF-1 in 67.5% of patients after 5 years (most likely due to lack of dose-up titration), and also improved clinical symptoms. Pegvisomant improves insulin sensitivity, and long-term follow-up showed significantly decreased fasting glucose over time, while the first-generation SRL only have a marginal clinical impact on glucose homeostasis in acromegaly. Pegvisomant does not have any direct anti-proliferative effects on pituitary tumour cells, but tumour growth is rare overall.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 30
Correct
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A collapsed patient comes into A&E. He has a steroid user card and empty boxes of prednisolone. He has obvious rheumatoid features on examination and some unilateral consolidation on his chest X-ray. He is given intravenous fluids and broad-spectrum antibiotics.
Which one of the following would be the most useful addition to the current management?Your Answer: IV hydrocortisone 100 mg
Explanation:The empty boxes indicate that the patient has run out of his medication.
Chronic administration of high doses of glucocorticoids (GCs) (e.g., prednisone or prednisolone) and also other hormones such as oestrogens, progestins, androgens and growth hormone induce varying degrees of tolerance, resulting in a progressively decreased response to the effect of the drug, followed by dependence and rarely addiction.
The glucocorticoid withdrawal syndrome (GWS) has been considered a withdrawal reaction due to established physical dependence on supraphysiological GC levels.
The severity of GWS depends on the genetics and developmental history of the patient, on his environment, and on the phase and degree of dependence the patient has reached. Its management should include a temporary increase in the dose of GCs followed by gradual, slow tapering to a maintenance dose. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 31
Correct
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A 55-year-old man known with Addison's disease presented with complaints of recurrent attacks of postural hypotension. What kind of electrolyte imbalance would be seen in his biochemical profile investigations?
Your Answer: Low Na+, High K+
Explanation:Patients suffering from Addison’s disease have low aldosterone. Aldosterone increases Na+ absorption and excretion of K+. So in these patients there would be decreased Na+ and increased K+ levels.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 32
Correct
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A 50-year-old woman came to the diabetes clinic for her regular follow up.
The following results are obtained:
Urine analysis: Protein+
HBA1c 86 mmol/mol (10.0%)
What is her average blood glucose level during the past 2 months?Your Answer: 15
Explanation:The level of haemoglobin A1c (HbA1c), also known as glycated haemoglobin, determines how well a patient’s blood glucose level has been controlled over the previous 8-12 weeks. Recent studies have been made to correlate between HbA1c and average glucose level.
Using the following formula: Average blood glucose (mmol/l) = (1.98 x 1 HbA1c) – 4.29 -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 33
Correct
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Which of the following electrolyte abnormalities is most likely to be seen in SIADH?
Your Answer: Low serum Na, low serum osmolarity, high urine osmolarity
Explanation:In SIADH, there is increased secretion of the ADH hormone resulting in increased water absorption. That’s why there would be decreased serum Na, decreased osmolarity and increased urine osmolarity.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 34
Incorrect
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Using DEXA, which of the following bone mineral density values indicates osteopenia in the measured site?
Your Answer: A T score of -1.8
Correct Answer: A T score of -2.6
Explanation:Osteopenia is an early sign of bone weakening that is less severe than osteoporosis.
The numerical result of the bone density test is quantified as a T score. The lower the T score, the lower the bone density. T scores greater than -1.0 are considered normal and indicate healthy bone. T scores between -1.0 and -2.5 indicate osteopenia. T scores lower than -2.5 indicate osteoporosis.
DEXA also provides the patient’s Z-score, which reflects a value compared with that of person matched for age and sex.
Z-score values of -2.0 SD or lower are defined as below the expected range for age and those above -2.0 SD as within the expected range for age. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 35
Correct
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A 66-year-old woman comes to you with a tender lump near the anal opening and a fever. She has history of T1DM for the last 20 years. What treatment should she get?
Your Answer: I&D + antibiotics
Explanation:Surgical incision and drainage is the most common treatment for anal abscesses. About 50% of patients with an anal abscess will develop a complication called a fistula. Diabetes is a risk factor for an anal abscess.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 36
Correct
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A 30-year-old previously well female presented with yellowish discolouration of her sclera. Investigations revealed low haemoglobin, a retic count of 8% and the occasional spherocyte on blood film. Which of the following is the most appropriate single investigation?
Your Answer: Direct coombs test
Explanation:A low haemoglobin and a high retic count is suggestive of a haemolytic anaemia. Occasional spherocytes can be seen on blood film during haemolysis and it is not a specific finding. Direct Coombs test will help to identify autoimmune haemolytic anaemia, where there are antibodies attached to RBCs.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 37
Correct
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Primary hyperaldosteronism is characterized by which of the following features?
Your Answer: Muscular weakness
Explanation:Primary hyperaldosteronism, also known as Conn’s Syndrome, is one of the most common causes of secondary hypertension (HTN).
The common clinical scenarios in which the possibility of primary hyperaldosteronism should be considered include the following:
– Patients with spontaneous or unprovoked hypokalaemia, especially if the patient is also hypertensive
– Patients who develop severe and/or persistent hypokalaemia in the setting of low to moderate doses of potassium-wasting diuretics
– Patients with treatment-refractory/-resistant hypertension (HTN)
Patients with severe hypokalaemia report fatigue, muscle weakness, cramping, headaches, and palpitations. They can also have polydipsia and polyuria from hypokalaemia-induced nephrogenic diabetes insipidus. Long-standing HTN may lead to cardiac, retinal, renal, and neurologic problems, with all the associated symptoms and signs. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 38
Incorrect
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Which of the following is correct regarding post-menopausal hormone replacement therapy (HRT) according to randomised clinical studies ?
Your Answer: Reduces cardiovascular mortality
Correct Answer: Increases plasma triglycerides
Explanation:Oestrogen therapy reduces plasma levels of LDL cholesterol and increases levels of HDL cholesterol. It can improve endothelial vascular function, however, it also has adverse physiological effects, including increasing the plasma levels of triglycerides (small dense LDL particles). Therefore, although HRT may have direct beneficial effects on cardiovascular outcomes, these effects may be reduced or balanced by the adverse physiological effects.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 39
Correct
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A 45-year-old obese patient arrives at the clinic for a regular health check up. His labs are as follows: Fasting blood sugar: 6 mmol/l, Oral glucose tolerance test (OGTT): 10 mmol/L. What is the most likely diagnosis?
Your Answer: Impaired glucose tolerance
Explanation:Impaired glucose tolerance means that blood glucose is raised beyond normal levels, but not high enough to warrant a diabetes diagnosis. With impaired glucose tolerance you face a much greater risk of developing diabetes and cardiovascular disease. Impaired glucose tolerance is defined as 2-hour glucose levels of 140 to 199 mg per dL (7.8 to 11.0 mmol) on the 75-g oral glucose tolerance test, and impaired fasting glucose is defined as glucose levels of 100 to 125 mg per dL (5.6 to 6.9 mmol per L) in fasting patients.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 40
Incorrect
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A 33-year-old woman presents to the clinic with chronic fatigue. She has 3 children and a full-time job and is finding it very difficult to hold everything together. There is no significant past medical history.
On examination, her BP is 145/80 mmHg and her BMI is 28.
Investigations show:
Hb 12.5 g/dl
WCC 6.7 x109/l
PLT 204 x109/l
Na+ 141 mmol/l
K+ 4.9 mmol/l
Creatinine 120 μmol/l
Total cholesterol 5.0 mmol/l
TSH 7.8 U/l
Free T4 10.0 pmol/l (10-22)
Free T3 4.9 pmol/l (5-10)
Which of the following is the most likely diagnosis?Your Answer: Hypothyroidism
Correct Answer: Subclinical hypothyroidism
Explanation:Elevated TSH (usually 4.5-10.0 mIU/L) with normal free T4 is considered mild or subclinical hypothyroidism.
Hypothyroidism commonly manifests as a slowing in physical and mental activity but may be asymptomatic. Symptoms and signs are often subtle and neither sensitive nor specific.
The following are symptoms of hypothyroidism:
– Fatigue, loss of energy, lethargy
– Weight gain
– Decreased appetite
– Cold intolerance
– Dry skin
– Hair loss
– Sleepiness
– Muscle pain, joint pain, weakness in the extremities
– Depression
– Emotional lability, mental impairment
– Forgetfulness, impaired memory, inability to concentrate
– Constipation
– Menstrual disturbances, impaired fertility
– Decreased perspiration
– Paraesthesia and nerve entrapment syndromes
– Blurred vision
– Decreased hearing
– Fullness in the throat, hoarseness
Physical signs of hypothyroidism include the following:
– Weight gain
– Slowed speech and movements
– Dry skin
– Jaundice
– Pallor
– Coarse, brittle, straw-like hair
– Loss of scalp hair, axillary hair, pubic hair, or a combination
– Dull facial expression
– Coarse facial features
– Periorbital puffiness
– Macroglossia
– Goitre (simple or nodular)
– Hoarseness
– Decreased systolic blood pressure and increased diastolic blood pressure
– Bradycardia
– Pericardial effusion
– Abdominal distention, ascites (uncommon)
– Hypothermia (only in severe hypothyroid states)
– Nonpitting oedema (myxoedema)
– Pitting oedema of lower extremities
– Hyporeflexia with delayed relaxation, ataxia, or both. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 41
Correct
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Following a head injury, a 22-year-old patient develops polyuria and polydipsia. He is suspected to have cranial diabetes insipidus so he undergoes a water deprivation test.
Which one of the following responses would most indicate a positive (abnormal) result?Your Answer: Failure to concentrate the urine during water deprivation, but achievement of urine osmolality of 720 mmol/kg following the administration of desmopressin
Explanation:The water deprivation test (i.e., the Miller-Moses test), is a semiquantitative test to ensure adequate dehydration and maximal stimulation of ADH for diagnosis. It is typically performed in patients with more chronic forms of Diabetes Insipidus (DI). The extent of deprivation is usually limited by the patient’s thirst or by any significant drop in blood pressure or related clinical manifestation of dehydration.
In healthy individuals, water deprivation leads to a urinary osmolality that is 2-4 times greater than plasma osmolality. Additionally, in normal, healthy subjects, administration of ADH produces an increase of less than 9% in urinary osmolality. The time required to achieve maximal urinary concentration ranges from 4-18 hours.
In central and nephrogenic DI, urinary osmolality will be less than 300 mOsm/kg after water deprivation. After the administration of ADH, the osmolality will rise to more than 750 mOsm/kg in central DI but will not rise at all in nephrogenic DI. In primary polydipsia, urinary osmolality will be above 750 mOsm/kg after water deprivation.
A urinary osmolality that is 300-750 mOsm/kg after water deprivation and remains below 750 mOsm/kg after administration of ADH may be seen in partial central DI, partial nephrogenic DI, and primary polydipsia. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 42
Incorrect
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A 35-year-old female presented with purple stretch marks on her abdomen, easy bruising and weight gain. A low dose Dexamethasone suppression test did not show any but a high dose Dexamethasone suppression test showed suppression of cortisol levels. Which of the following is the most likely cause for this presentation?
Your Answer: Pseudo-cushing's
Correct Answer: Pituitary Adenoma
Explanation:Clinical features are due to excess cortisol. High-dose dexamethasone suppression test shows suppression in patients with Cushing’s disease. Cushing syndrome includes all causes of glucocorticoid excess, whereas Cushing’s disease is reserved only for pituitary-dependent Cushing’s syndrome.
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 43
Correct
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A 50-year-old woman was investigated following an osteoporotic hip fracture. The following results are obtained:
TSH < 0.05 mu/l
Free T4 29 pmol/l
Which of the following autoantibodies is most likely to be present?Your Answer: TSH receptor stimulating autoantibodies
Explanation:The patient has hyperthyroidism and its most common cause is Grave’s Disease.
Grave’s Disease is an autoimmune disease due to circulating autoantibodies known as TSH receptor stimulating autoantibodies or Thyroid-stimulating immunoglobulins (TSIs) that bind to and activate thyrotropin receptors, causing the thyroid gland to grow and the thyroid follicles to increase the synthesis of thyroid hormone. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 44
Correct
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A 45-year-old man presents with tiredness and central weight gain.
He underwent pituitary surgery for a non-functional pituitary tumour two years ago. Although he recovered from his pituitary surgery well, he has been found to have complete anterior hypopituitarism. Accordingly he is receiving stable replacement therapy with testosterone monthly injections, thyroxine and hydrocortisone.
On examination, there are no specific abnormalities, his vision is 6/9 in both eyes and he has no visual field defects.
From his notes, you see that he has gained 8 kg in weight over the last six months and his BMI is 31. His blood pressure is 122/72 mmHg.
Thyroid function tests and testosterone concentrations have been normal. A postoperative MRI scan report shows that the pituitary tumour has been adequately cleared with no residual tissue.
Which of the following is the most likely cause of his current symptoms?Your Answer: Growth hormone deficiency
Explanation:The somatotroph cells of the anterior pituitary gland produce growth hormone (GH).
GH deficiency in adults usually manifests as reduced physical performance and impaired psychological well-being. It results in alterations in the physiology of different systems of the body, manifesting as altered lipid metabolism, increased subcutaneous and visceral fat, decreased muscle mass, decreased bone density, low exercise performance, and reduced quality of life. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 45
Correct
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A 40-year-old woman presents with weight loss, palpitations, diarrhoea and cessation of periods. She has been treated by her GP for anxiety. Examination reveals a single nodule on the left of her thyroid, about 1.5 cm in diameter.
Thyroid scan shows increased uptake within the nodule with reduced activity throughout the rest of the gland.
Thyroid function tests showed a free thyroxine of 30 pmol/l (9-25 pmol/l), TSH < 0.05 mU/l (0.5-5).
Based on these findings, what would be the definitive treatment?Your Answer: Radioactive iodine therapy
Explanation:Patients who have autonomously functioning nodules should be treated definitely with radioactive iodine or surgery.
Na131 I treatment – In the United States and Europe, radioactive iodine is considered the treatment of choice for Toxic Nodular Goitre. Except for pregnancy, there are no absolute contraindications to radioiodine therapy. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 46
Incorrect
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A 55-year-old man with a three-year history of type 2 diabetes comes to the clinic for review. He is currently managed with metformin 1 g BD and feels that his home blood glucose monitoring has deteriorated over the past few months. There is a history of hypertension and dyslipidemia for which he takes Ramipril 10 mg daily and atorvastatin 20 mg.
On examination, his BP is 155/82 mmHg, his pulse is 71 and regular. His chest is clear. His BMI is 32.
Investigations show:
Haemoglobin 12.9 g/dl (13.5 - 17.7)
White cell count 5.0 x109/l (4 - 11)
Platelets 180 x109/l (150 - 400)
Sodium 140 mmol/l (135 - 146)
Potassium 5.0 mmol/l (3.5 - 5)
Creatinine 123 mmol/l (79 - 118)
HbA1c 8.0% (<7.0)
He would like to start sitagliptin.
Which of the following adverse effects would you warn him about?Your Answer: Osteoporosis
Correct Answer: Pancreatitis
Explanation:Sitagliptin-induced pancreatitis can occur at any time after the initiation of therapy, even after several years. Patients taking sitagliptin who present with signs and symptoms of mild or severe pancreatitis should immediately discontinue sitagliptin and use an alternate medication regimen for control of type 2 diabetes.
In response to pancreatitis reported in post-marketing surveillance through the Adverse Event Reporting System (AERS), the FDA has issued revised prescribing information for sitagliptin stating that cases of acute pancreatitis have been reported with use, to monitor closely for signs and symptoms of pancreatitis, and to use sitagliptin with caution in patients with a history of pancreatitis. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 47
Correct
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A 25-year-old man wants to start a relationship but is concerned about his small phallus. He also has difficulty becoming aroused. On examination, he is slim and has gynecomastia. There is a general paucity of body hair, his penis and testes are small.
Which diagnosis fits best with this history and examination?Your Answer: Klinefelter's syndrome
Explanation:The patient most likely has Klinefelter’s syndrome.
Klinefelter syndrome (KS) refers to a group of chromosomal disorders in which the normal male karyotype, 46,XY, has at least one extra X chromosome. XXY aneuploidy, the most common human sex chromosome disorder. It is also the most common chromosomal disorder associated with male hypogonadism and infertility.
Klinefelter syndrome is characterized by hypogonadism (micro-orchidism, oligospermia/azoospermia), gynecomastia in late puberty, hyalinization and fibrosis of the seminiferous tubules, elevated urinary gonadotropin levels, and behavioural concerns. -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 48
Correct
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A 60-year-old man known to have type 2 diabetes comes for regular follow up. He is on metformin 2 g per day and gliclazide 160 mg per day. His recent HbA1c was 8.4% and his blood pressure was 140/75 mmHg. Eye examination reveals dot and blot haemorrhages and microaneurysms. None are close to the macula.
Which of the following defines his eye condition?Your Answer: Background diabetic retinopathy
Explanation:Patients with diabetes often develop ophthalmic complications, the most common and potentially most blinding of these complications is diabetic retinopathy.
The following are the 5 stages in the progression of diabetic retinopathy:
1. Dilation of the retinal venules and formation of retinal capillary microaneurysms.
2. Increased vascular permeability.
3. Vascular occlusion and retinal ischemia.
4. Proliferation of new blood vessels on the surface of the retina.
5. Vitreous haemorrhage and contraction of the fibrovascular proliferation.
The first 2 stages of diabetic retinopathy are known as background or nonproliferative retinopathy. Initially, the retinal venules dilate, then microaneurysms (tiny red dots on the retina that cause no visual impairment) appear. As the microaneurysms or retinal capillaries become more permeable, hard exudates appear, reflecting the leakage of plasma.Mild nonproliferative diabetic retinopathy (NPDR) or background diabetic retinopathy is indicated by the presence of at least 1 microaneurysm, while neovascularization is the hallmark of Proliferative Diabetic Retinopathy (PDR).
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This question is part of the following fields:
- Endocrine System & Metabolism
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Question 49
Incorrect
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A 58-year-old woman has multiple non-healing leg ulcers. She reports feeling unwell for several months. Examination findings include a normal blood pressure, pulse 90 bpm, pale conjunctivae and poor dentition associated with bleeding gums. What is the most likely underlying diagnosis?
Your Answer: Vitamin B12 deficiency
Correct Answer: Vitamin C deficiency
Explanation:Severe vitamin C deficiency results in scurvy, a disorder characterized by hemorrhagic manifestations and abnormal osteoid and dentin formation.
Vitamin C plays a role in collagen, carnitine, hormone, and amino acid formation. It is essential for bone and blood vessel health and wound healing and facilitates recovery from burns. Vitamin C is also an antioxidant, supports immune function, and facilitates the absorption of iron (see table Sources, Functions, and Effects of Vitamins).
Dietary sources of vitamin C include citrus fruits, tomatoes, potatoes, broccoli, strawberries, and sweet peppers. (See also Overview of Vitamins.) -
This question is part of the following fields:
- Endocrine System & Metabolism
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Question 50
Correct
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A 30-year-old man presented with polydipsia and polyuria for the last two years.
Investigations reveal:
Serum urea 9.5 mmol/L (2.5-7.5)
Serum creatinine 108 mol/L (60-110)
Serum corrected calcium 2.9 mmol/L (2.2-2.6)
Serum phosphate 0.7 mmol/L (0.8-1.4)
Plasma parathyroid hormone 6.5 pmol/L (0.9-5.4)
Which of the following is directly responsible for the increase in intestinal calcium absorption?Your Answer: 1,25 Dihydroxy vitamin D
Explanation:This patient has hypercalcaemia due to hyperparathyroidism. However, the intestinal absorption of calcium is mainly controlled by 1,25 dihydroxy-vitamin D. Under the influence of calcitriol (active form of vitamin D), intestinal epithelial cells increase their synthesis of calbindin (calcium-binding carrier protein) necessary for active calcium ion absorption.
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This question is part of the following fields:
- Endocrine System & Metabolism
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