Strategies for rhEPO detection in sport

This article examines available strategies for the detection of recombinant erythropoietin (rhEPO) abuse in sport. RhEPO was quickly recognized as an effective but hazardous performance-enhancing agent. In the absence of a valid procedure to detect rhEPO doping, at-competition health checks were introduced, which excluded athletes from competition when their hemoglobin or hematocrit values exceeded an arbitrary limit. This limited the danger to athletes, but did nothing to eliminate the use of rhEPO. Through the last decade, both direct and indirect methods for detecting rhEPO were investigated. No single indirect marker was found that satisfactorily demonstrated rhEPO use. A combination of blood and urine tests together formed the procedure and strategy approved by the International Olympic Committee (IOC) for detecting rhEPO use at the Sydney Olympics. However strategies for testing for EPO are as important as the developed laboratory analytical procedures. The use of extensive out-of-competition testing and analysis within the IOC accredited laboratory system is critical to any testing program. At-competition blood tests have merit as true health checks and will also be needed to detect acutely useful agents such as hemoglobin-based oxygen carriers. However the persistence of the "health check" rationale for on-site at-competition rhEPO testing has led to much wasted testing effort, as rhEPO use by athletes will rarely occur near to or at the time of the competition for fear of detection. Thus, direct testing methods (such as the rhEPO urine test) especially will fail due to the completed metabolism and elimination of administered rhEPO before the test, unless the international sporting federations use the information gathered to assist in targeted out-of-competition testing. This article discusses the limitations of testing at competition and proposed strategies for dealing with various phases of EPO doping in detail, concluding that no one single currently used strategy will detect all users of rhEPO. The development of strategies to diagnose rhEPO abuse may serve as a model to detect other biological agents.