Endocrine

Question 1

What complications occur independent of hyperthyroidism

Answer 1

Graves orbitopathy and neonatal thyrotoxicosis are independent of hyperthyroidism

Question 2

An elderly male of no fixed abode with a history of alcohol dependency and chronic liver disease is taken to the Emergency Department with reduced consciousness (GCS 5) and a blood glucose of 1.3 mmol/L.
What is the correct management of his hypoglycaemia
A. IM glucagon stat
B. Lucozade
C. 100mL IV normal saline
D. 100mL IV dex 5%
E. 100mL IV gluose 20%

Answer 2

E

Hypoglycaemia in patients with alcoholic liver disease does not respond to glucagon
Patients with alcoholic liver disease have depleted glycogen stores, therefore, treatment with glucagon does not improve blood glucose.

Question 3

A 74-year-old male is admitted to the Emergency Department after routine blood tests by his GP showed the following results. The patient has a background of stable essential thrombocytosis.

Na+ 139 mmol/l
K+ 6.6 mmol/l
Urea 4.2 mmol/l
Creatinine 68 umol/l

Hb 13.5 g/dl
Plt 800 *109/l
WBC 6.6 *109/l

His ECG was normal and he was given calcium gluconate along with an insulin/dextrose infusion. Following this his potassium improved to 6.1, however over the next few days he remained persistently hyperkalaemic.

What would you suspect is the cause of his high potassium given his high cell counts?
A. Pseudohyperkalaemia
B. Tumour lysis syndrome 
C. Hypomagnesaemia
D. Conns syndrome 
E. CKD

Answer 3

A - pseudohyperkalaemia
High cell counts and high potassium: consider pseudohyperkalaemia

Pseudohyperkalaemia is a rise in serum potassium that occurs due to excessive leakage of potassium from cells, during or after blood is taken. It is a laboratory artefact and does not represent the true serum potassium concentration. The majority of potassium is intracellular and thus leakage from cells can significantly impact serum levels. In this case the potassium is released as the large numbers of platelets aggregate and degranulate.

Causes include:
haemolysis during venepuncture (excessive vacuum of blood drawing or too fine a needle gauge)
delay in the processing of the blood specimen
abnormally high numbers of platelets, leukocytes, or erythrocytes (such as myeloproliferative disorders)
familial causes

Measuring an arterial blood gas will give a quick and accurate measure of true serum potassium. For obtaining a lab sample, using a lithium heparin tube, requesting a slow spin (on the lab centrifuge) and walking the sample to the lab should ensure an accurate result.