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

1. A 33-year-old man was referred to the diabetes clinic with an 8-month history of weight loss and polydipsia. Two months previously his general practitioner had found a high fasting plasma glucose concentration of 17.5 mmol/L (3.0-6.0) and a haemoglobin A1c of 116 mmol/mol (20-42). The patient was taking metformin 1 g twice daily. He reported in the diabetes clinic that his home capillary blood glucose concentrations persisted to be high, ranging between 15-24 mmol/L.
On examination, his body mass index was 23 kg/m2 (18-25).
His blood tests were repeated in the diabetes clinic and he was treated with a basal bolus insulin regimen. Urinalysis was negative for ketones.
Investigations (in diabetes clinic):
haemoglobin A1c110 mmol/mol (20-42)
serum C-peptide200 pmol/L (180-360)
anti-glutamic acid decarboxylase (GAD)
antibodies69 IU/mL (<10)
anti-IA2 antibodiesnegative
What is the most likely diagnosis?

A) maturity-onset diabetes of the young
B) type 1 diabetes mellitus
C) mitochondrial diabetes mellitus
D) latent autoimmune diabetes in adults
E) haemochromatosis

2. A 60-year-old man with type 2 diabetes mellitus attended for an elective laparoscopic cholecystectomy. His oral hypoglycaemic medication regimen was metformin 1 g twice daily and gliclazide 160 mg twice daily. His haemoglobin A1c concentration had been 69 mmol/mol (20-42) when checked 2 months previously.
He was admitted on the morning of surgery and was on the morning list. He had fasted from midnight and taken metformin 1 g at 05.00 h.
On examination, he weighed 82 kg.
Investigations (on admission):
serum creatinine64 umol/L (60-110)
fasting plasma glucose18.1 mmol/L (3.0-6.0)
capillary blood ketones0.2 mmol/L (<1)
According to the Joint British Diabetes Societies guideline 'Management of adults with diabetes undergoing surgery and elective procedures', what is the most appropriate next step in management to bring his preoperative glucose into the acceptable range (4.0-12.0 mmol/L)?

A) rapid-acting analogue insulin 16 units subcutaneously
B) gliclazide 160 mg orally
C) cancel surgery and refer to local diabetes team
D) variable-rate insulin infusion
E) rapid-acting analogue insulin 8 units subcutaneously

3. A 73-year-old man with type 2 diabetes mellitus was reviewed because of borderline hypertension. He was taking metformin 1 g twice daily, gliclazide 160 mg twice daily, aspirin 75 mg daily and simvastatin 20 mg at night. He had a history of diabetic retinopathy.
On examination, his body mass index was 34 kg/m2 (18-25); his blood pressure was 146/86 mmHg. When he returned 2 months later, his blood pressure was 142/88 mmHg.
Investigations:
serum creatinine102 umol/L (60-110)
haemoglobin A1c66 mmol/mol (20-42)
urinary albumin:creatinine ratio
(untimed specimen)7.4 mg/mmol (<2.5)
According to NICE guidelines (CG66, May 2008), what is the target for blood pressure reduction?

A) <130/80 mmHg
B) <125/70 mmHg
C) <120/70 mmHg
D) <140/80 mmHg
E) <150/90 mmHg

4. A 16-year-old boy was referred to the diabetes clinic following the discovery of a random plasma glucose concentration of 18.0 mmol/L. His general practitioner had begun treatment with metformin. The patient had a body mass index of 35 kg/m2 (18-25). He had had problems throughout his childhood, and had been taken out of school and was educated at home by his mother. He was attending the ophthalmology clinic for visual problems.
On examination, he was obese. He had hearing aids in both ears and evidence of acanthosis nigricans. Neither parent had a history of diabetes mellitus.
What is the most likely diagnosis?

A) hepatocyte nuclear factor 1? mutation
B) type 2 diabetes mellitus
C) Alstrom's syndrome
D) mitochondrial diabetes
E) Bardet-Biedl syndrome

5. A 75-year-old woman presented with a 4-week history of lethargy. Her medical history was unremarkable and she took no medication.
On examination, her blood pressure was 140/70 mmHg lying. She was euvolaemic.
Investigations:
serum sodium120 mmol/L (137-144)
serum potassium3.8 mmol/L (3.5-4.9)
serum urea3.0 mmol/L (2.5-7.0)
serum creatinine75 umol/L (60-110)
short tetracosactide (Synacthen@) test (250 micrograms):
baseline serum cortisol450 nmol/L (200-700)
serum cortisol (30 min after tetracosactide)600 nmol/L (>550)
serum thyroid-stimulating hormone2.5 mU/L (0.4-5.0)
serum free T416.9 pmol/L (10.0-22.0)
urinary sodium70 mmol/L
What is the most appropriate initial management?

A) intravenous sodium chloride 0.9%
B) hydrocortisone
C) demeclocycline
D) tolvaptan
E) fluid restriction

Solutions: