Endocrine Abstracts

Postural orthostatic tachycardia syndrome (PoTS) reflects a disturbance of autonomic function leading to a myriad of clinical features. Subcutaneous octreotide injections and intramuscular long acting preparations of octreotide have been used in the treatment of PoTS. However, inconvenience of frequent injections, side effects and theoretical overexposure, as well as cost of the intramuscular preparation, makes them far from ideal.

We present a case of uncontrolled severe PoTS rectified through the novel use of octreotide via an insulin pump.

A 22-year-old woman presented in April 2002 with episodic palpitations associated with chest discomfort, dyspnoea, and pre-syncope. After 3 years of inconclusive investigations, deteriorating symptomatic control leaving her off work, wheelchair bound, recovering from multiple syncopal related long bone fractures, depression and with a poor quality of life, a diagnosis of PoTS was considered. Diagnostic tilt table testing identified pre-syncope associated with sinus tachycardia, maximum heart rate rise of 42 bpm, and decreases in blood pressure confirming PoTS.

Several therapies including fludrocortisone, slow sodium, midodrine, ephedrine and ivabradine were either ineffective or caused intolerable side effects. In May 2010, SC octreotide, 50 μg every 90 min six times a day (300 μg/24 h), was trialled. Despite her PoTS symptoms improving, she reported excruciating abdominal cramps and diarrhoea following each injection. The severity and frequency of side effects prompted the use of subcutaneous octreotide via an Animas insulin pump in 2011. The patient received 10 μg/h of octreotide for 12 h (120 μg/24 h). The patient reported significant improvements in physical function and ability to maintain upright posture with no side effects. She returned to work and her quality of life improved.

Conclusion: Delivery of octreotide via an insulin pump provides a novel therapeutic strategy in the management of PoTS using lower doses and achieving symptom control with fewer side effects compared to subcutaneous octreotide.