Sir, I write regarding the issue of steroid cover in the prevention of an adrenal crisis.1 Patients who are susceptible would not be able to produce enough endogenous steroids to cope with the stress of certain procedures. Acute adrenal insufficiency is a life threatening complication in these patients and has a vague presentation making its diagnosis difficult. Symptoms may include weakness, abdominal pain, salt craving, diarrhoea, constipation and syncope. Unfortunately, there are a multitude of other differentials that may distract from making a prompt diagnosis and instituting correct management.2

In our setting, the most common cause for this insufficiency is suppression of the hypothalamic-pituitary axis from chronic exogenous steroid usage (secondary adrenal insufficiency).3 Adrenal crisis may then result from an acute exacerbation of chronic insufficiency, caused in this case by surgical stress. This is particularly the case in patients having steroid replacement therapy for more than four years.4

Such varying guidelines are encountered in the management of other conditions and are continually evolving.5 These include antibiotic prophylaxis in prevention of infective endocarditis, INR levels and, more recently, cessation of aspirin and other antiplatelet medications pre-operatively to minimise intra and post operative haemorrhage.

As there is an objective test for adrenal gland function – the synacthen test (short or long) – it is possible to resolve any suggestions of insufficiency. The short test is relatively quick, and performed usually in the morning involving two blood samples taken 30 minutes apart and a small intramuscular injection given after the first sample is taken. A plasma cortisol response of >500 nmol/L can help exclude adrenal atrophy due to Addison's Disease or steroid therapy.

Given the current evolution of evidence based medicine would it not be considered prudent to consider such a test to provide some objectivity to our management in these cases? Does further work need to be done to establish the reliability of this procedure in testing for the risk of acute adrenal insufficiency after surgery?