MRCPUK Endocrinology and Diabetes (Specialty Certificate Examination) Sample Questions:

1. A 54-year-old man was referred from the urology department with erectile dysfunction.
On examination, he had normal secondary sexual characteristics. Testicular volume was
estimated at 15 mL bilaterally.
Investigations:
random plasma glucose8.0 mmol/L
serum testosterone8.1 nmol/L (9.0-35.0) plasma follicle-stimulating hormone3.4 U/L (1.0-7.0) plasma luteinising hormone4.7 U/L (1.0-10.0) serum prolactin410 mU/L (<360)
What is the most appropriate next step in management?

A) prescribe sildenafil
B) prescribe testosterone replacement
C) serum testosterone (09.00 h)
D) fasting plasma glucose
E) check for macroprolactinaemia

2. A 45-year-old woman attended for annual follow-up for long-standing hypoparathyroidism (a complication of thyroid surgery 5 years previously). She was asymptomatic. She was taking alfacalcidol 1 microgram daily.
Examination was unremarkable.
Investigations:
serum creatinine105 umol/L (60-110)
serum corrected calcium2.45 mmol/L (2.20-2.60)
24-h urinary calcium9.8 mmol (2.5-7.5)
What is the most appropriate next step in management?

A) decrease alfacalcidol dosage
B) change alfacalcidol to calcitriol
C) recommend low-calcium diet
D) change alfacalcidol to teriparatide
E) add bendroflumethiazide

3. A 43-year-old man presented with a 2-year history of tiredness and reduced libido. He had not been found to have diabetes mellitus.
On examination, his body mass index was 22.4 kg/m2 (18-25), he was poorly virilised and had 10 mL testes.
Investigations:
serum cortisol (09.00 h)220 nmol/L (200-700) serum testosterone4 nmol/L (9.0-35.0) plasma follicle-stimulating hormone1.2 U/L (1.0-7.0) plasma luteinising hormone1.2 U/L (1.0-10.0) serum prolactin150 mU/L (<360) serum thyroid-stimulating hormone1.2 mU/L (0.4-5.0) serum free T48.2 pmol/L (10.0-22.0)
serum insulin-like growth factor 17.8 nmol/L (5.6-23.3)
MR scan of pituitaryempty sella; no mass lesion
An insulin tolerance test was advised to assess both cortisol and growth hormone reserve.
What is the most appropriate dose of insulin (in units/kg body weight) to administer?

A) 0.5
B) 0.1
C) 0.01
D) 1.0
E) 0.05

4. A 33-year-old woman was seen for diabetes review 2 months after her first pregnancy. Diabetes mellitus had been diagnosed at 18 weeks' gestation. She had experienced no symptoms; routine urinalysis had shown glucose 4+, with no ketones, and her fasting blood glucose concentration was 6.2 mmol/L (3.0-6.0), rising to 13.5 mmol/L (<7.8) in a 75-g oral glucose tolerance test. She had been treated with insulin during the pregnancy, and stopped after delivery. Her mother and maternal aunt had been treated for type 2 diabetes mellitus, and a maternal uncle for type 1 diabetes. Her body mass index was 23.7 kg/m2 (18-25).
Without insulin she remained well, with no osmotic symptoms, no weight loss and no ketosis.
Investigations:
fasting plasma glucose8.4 mmol/L (3.0-6.0)
haemoglobin A1c68 mmol/mol (20-42)
oral glucose tolerance test (75 g):
fasting plasma glucose7.9 mmol/L (3.0-6.0)
2-h plasma glucose13.8 mmol/L (<7.8)
serum insulin72 pmol/L (<186)
serum C-peptide945 pmol/L (180-360)
A trial of therapy with gliclazide 40 mg once daily led to a significant improvement in her blood glucose.
What is the most likely cause of her diabetes?

A) latent autoimmune diabetes in adulthood
B) type 1 diabetes mellitus
C) maturity-onset diabetes of the young caused by HNF-1? mutation
D) maturity-onset diabetes of the young caused by glucokinase mutation
E) type 2 diabetes mellitus

5. A 37-year-old woman presented with a 2-year history of increasingly frequent flushing episodes. She described alternating loose bowel motions and constipation. She had also noted menstrual irregularity. She had no respiratory symptoms. She denied headache or chest pain, but complained of palpitations.
On examination, she appeared well. Her blood pressure was 128/82 mmHg.
Investigations:
serum thyroid-stimulating hormone0.8 mU/L (0.4-5.0)
What is the most appropriate next investigation?

A) urinary 5-hydroxyindoleacetic acid
B) fasting plasma gut hormones
C) urinary metanephrines
D) serum gonadotrophins
E) plasma metanephrines

Solutions: