Context: The insulin tolerance test (ITT) is the gold standard for assessment of the pituitary adrenal axis but its use is limited because of concerns relating to the risk of hypoglycaemia. Objective: This study examined the depth and duration of hypoglycaemia achieved during the test in a large cohort of patients. Design: Two hundred and twenty ITTs were performed from 2005 to 2010. Setting: A 1200-bed University Teaching Hospital. Patients: Two hundred and twenty ITTs were carried out in patients with suspected or known pituitary disorders. Interventions: Intravenous insulin was administered to achieve nadir plasma glucose (NPG) of 2.2 mmol/l (39.6 mg/dl). Blood chemistry to show the cortisol and GH response to hypoglycaemic stress was measured. Main outcome measures: Predictors of depth and duration of hypoglycaemia, adverse events and within-subject variability of nadir glucose, peak cortisol and peak GH were studied. Results: Thirty percent of the cohort achieved a nadir glucose of !2.0 mmol/l (36 mg/dl) that lasted for 60 min or more. The NPG correlated positively with fasting plasma glucose (FPG; rZ0:56; P!0.0005), insulin dose (rZ0.27; P!0.0005) and weight (rZ0.21; P!0.004). The within subject variability of nadir glucose was 15.2%, peak cortisol was 11.7% and peak GH was 6.4%. The factors determining nadir blood glucose were FPG (bZ0.56, P!0.0005, 20% contribution) and weight (bZ0.14, P!0.05, 2% contribution). The five patients with adverse events had NPG and insulin dose comparable with the rest of the population. Conclusions: The hypoglycaemia achieved during the ITT is much lower than the target required. However, adverse events are few and do not relate to the depth of hypoglycaemia.

No abstract

We present an unusual case of Addison's disease due to bilateral adrenal infarction in a patient with myelodysplasia. To our knowledge, bilateral adrenal infarction in association with myelodysplasia has not been reported previously.

The United Kingdom Prospective Diabetes Study demonstrated the importance of good glycaemic control in patients with type 2 diabetes. Despite this knowledge, half of the population with diabetes have an HbA1c above 8%. Five general practices in Torbay identified all patients with type 2 diabetes and suboptimal glycaemic control (HbA1c >7.5%) who were not on insulin. A retrospective review of the general practice records of patients was performed. Patients were categorised into: need to consider insulin; need to increase oral agents; treatment has recently been appropriately increased; patient plans to commence insulin; insulin considered inappropriate or patient declined insulin; patient under a secondary care diabetes team; patient diagnosed with diabetes within the last year. In all, 376 patients with an HbA1c >7.5% were identified. Of these, 118 patients (31.4%) had appropriately increased their oral medication. Only 21 had discussed insulin initiation but an additional 74 were classified as needing to consider insulin therapy. Twenty‐three percent required an increase in their oral hypoglycaemic medication. Insulin was declined by the patient or thought inappropriate in 49 cases. There were 17 new diagnoses and only eight under secondary care. In conclusion, 43% of patients with type 2 diabetes and HbA1c >7.5% required an increase in oral medication or consideration for insulin. This need had not been recognised in the majority of cases. We believe that closer liaison between primary care and specialist diabetes teams is required. Copyright © 2008 John Wiley & Sons.