A common problem in the elderly with an uncommon cause: hypoglycaemia secondary to the Doege-Potter syndrome.

Falls due to hypoglycaemia in the elderly is usually a complication of diabetic treatment. In the absence of diabetes, hypoglycaemia may be due to insulin or insulin-like producing tumours. The Doege-Potter syndrome is a rare paraneoplastic syndrome, characterised by non-islet cell tumour hypoglycaemia (NICTH) secondary to a solitary fibrous tumour that secretes insulin-like growth factor (IGF) 2. Definitive treatment of hypoglycaemia due to NICTH is by tumour resection. Our patient was a 78-year-old woman admitted after a fall with a facial injury and a history of significant weight loss. Her blood sugar was persistently low despite intravenous dextrose infusion. CT of the thorax revealed a large heterogeneous mass measuring 11.6×16.3×15.6 cm in the right hemithorax. A biopsy of the mass was reported as a solitary fibrous tumour. Biochemical investigations revealed low insulin, C-peptide, IGF-1 and a high IGF-2:IGF-1 ratio, consistent with NICTH. The patient underwent tumour resection and the hypoglycaemia normalised completely immediately after surgery. 2015 BMJ Publishing Group Ltd.