Endocrine Abstracts

A 20-year-old man with a 5-year history of poorly controlled type 1 diabetes presented with epigastric pain, bloating and weight loss. He had attended DAFNE recently and had been commenced on an insulin Pump resulting in improvement of HbA1C from 114 to 76 mmol/mol over a 4-month period. Blood pressure was elevated (157/108 mmHg) with a resting tachycardia of 110. Haemoglobin was elevated at 18.7 g/dl. 24 h blood pressure monitoring revealed an average diastolic blood pressure of 120 mmHg and he was admitted for further investigation and management. Doxazosin caused his blood pressure to drop to 68/40 mmHg and was discontinued. MRI adrenals and MRA of the renal arteries did not reveal any significant abnormality. The patient did not want to remain in hospital, and was discharged with close follow-up in an ambulatory care setting.

Twenty-four hour urinary noradrenaline levels were elevated at 904 nmol/24 h (70–550). Subsequently, the result of plasma metanephrines taken during his hospital admission became available and were within normal range. Following this result, he was commenced on metoprolol. Midodrine, an alpha-1 receptor agonist, was subsequently commenced for severe symptomatic orthostatic hypertension. Average 24 h blood pressure on this combination was 136/87 mmHg. Due to on-going weight loss with BMI of 15.7, he required input from dieticians.

Four months later, his weight has increased by 3 kg. His symptoms of postural hypotension are only occasional and his midodrine dose has been reduced.

Acute insulin neuritis can be precipitated by rapid improvements in blood glucose control. This resulted in acute autonomic neuropathy with marked autonomic over-activity and some features suggestive of phaeochromocytoma. Clinical history and normal plasma metanephrines helped secure the diagnosis and tailor management.