Introduction

While generally considered benign, sickle cell trait (SCT) is both common and associated with a risk of sudden exertional death. Indeed, all high-level US intercollegiate athletes now face mandatory screening, raising legal and ethical concerns that resonate given the 2012 London Olympics' role in driving universal sports' participation, and increasing public health messaging promoting physical activity. This issue is also of substantial clinical and scientific interest: the pathogenesis of such deaths is unknown and successful management thus impeded.

This article discusses both clinical presentation and relevant (patho)physiology. It also proposes that a vicious cycle of skeletal muscle microvascular occlusion and ‘metabolic failure’ drives potassium efflux from erythrocytes and myocytes and therefore, hyperkalaemic death. Such discussion may be of value to all dealing with subjects with SCT in the community, to emergency/intensive care physicians who treat such cases and to researchers seeking new methods of screening and modes of treatment.