A 30-year-old Chinese patient presents with a history of
weakness of both lower and upper limbs. The weakness started overnight in his
lower limbs and spread to involve the upper limbs as well.
The patent had been well till then and had not had any
diarrhoea or vomiting. He had not lost any weight. There were no significant
On examination he looked well, fully orientated in place,
time and person. No evidence of
weight loss, temperature 37°C. Pulse rate 65 beats per minute
regular. BP 120/60. No rash, skin warm and dry. No lymphadenopathy.
On neurological examination of his limbs tone was normal
there was weakness of all four limbs, reflexes were diminished, plantars
downgoing, no sensory loss.
ESR not elevated
Glucose 7.5 mmol/l
Na 140 mmol/l
K 1.6 mmol/l
Chloride 104 mmol/l pH 7.39
In this patient, whilst awaiting the results of his blood
tests, what bedside investigation would give you a clue to the cause of the
Urine for ketone bodies
Specific gravity of urine
What other investigation would you arrange for this
patient to determine the aetiology of his condition?
Thyroid function tests
Overnight dexamethasone suppression test
Aldosterone plasma rennin activity ratio
Adrenal CT scan