Management of refractory hypoglycaemia in a metastatic neuroendocrine tumour co-secreting serotonin and insulin.

A 27-year-old otherwise healthy man of African descent presented to the hospital with initial symptoms of carcinoid syndrome that later evolved into symptoms of hyperinsulinemic hypoglycaemia. Investigations revealed a metastatic neuroendocrine tumour (NET), co-secreting both serotonin and insulin. Management involved a multimodal approach in an attempt to reduce tumour burden and achieve euglycaemia, which proved to be a significant challenge in the face of refractory hypoglycaemia despite the administration of multiple prohyperglycaemic agents in combination. Unfortunately, given the burden of metastatic disease and multiple medical complications that ensued, the patient passed away. This case highlights the clinical history of a NET co-secreting serotonin and insulin, the use of combination therapy in the treatment of refractory hypoglycaemia in a metastatic insulin-producing tumour and emerging therapeutic modalities in the treatment of these rare malignancies.

Subcutaneous versus intraperitoneal insulin for patients with diabetes mellitus on continuous ambulatory peritoneal dialysis: meta-analysis of non-randomized clinical trials.

BACKGROUND: Diabetes mellitus is one of the leading causes of end stage renal disease. Use of intraperitoneal (IP) nsulin in diabetic patients on peritoneal dialysis (PD) can restore glucose control to near normal values. The safety and efficacy of this method is unclear. METHODS: We performed a meta-analysis to study the safety and efficacy of IP insulin administration in diabetic patients on PD. The primary outcome measures is glycemic control: secondary outcome measures were plasma lipids, insulin dose requirement/day and the risk of peritonitis and hepatic subcapsular steatosis. Medline, EMBASE, Cochrane Central Register of Controlled Trials, and reference lists of eligible studies were searched. Eligible studies included randomized and non-randomized controlled trials that allocated adult PD diabetic patients to IP insulin and subcutaneous (SC) insulin. RESULTS: Twenty one citations were identified and three met the eligibility criteria. Glycemic control with IP insulin, as assessed with HbA1C, was equal to or better than that obtained with SC insulin: weighted mean difference was -1.49 % (95% CI: -2.17 to - 0.27, p=0.0001). The insulin dose required was more than two-fold higher in the IP treatment. Serum HDL-cholesterol decreased during IP insulin therapy while serum triglyceride (TG) concentration tended to increase, in comparison with levels seen in patients treated with SC insulin. CONCLUSIONS: Use of IP insulin provides adequate glycemic control, which appears superior to that seen following treatment with conventional SC insulin. The plasma lipids are adversely affected by IP insulin, possibly contributing to increased cardiovascular risk. Data are limited and further studies are needed to assess for the long-term safety of this approach.