A novel method utilizing markers of altered erythropoiesis for the detection of recombinant human erythropoietin abuse in athletes

Background and Objectives. The use of recombinant human erythropoietin (r-H uEPO) to enhance athletic performance is prohibited. Existing tests cannot readily differentiate between exogenous and endogenous EPO. Therefore the a im of our study was to investigate possible indirect detection of r-HuEPO U se via blood markers of altered erythropoiesis. Design and Methods. Twenty-seven recreational athletes were assigned to thr ee groups prior to a 25 day drug administration phase, with the following p rotocols: EPO+IM group(n = 10), 50 Ukg(-1) r-HuEPO at a frequency of 3wk(-1 ), 100 mg intramuscular (IM) Iron 1wk(-1) and a sham iron tablet daily; EPO +OR group (n = 8), 50 U.kg(-1) r-HuEPO 3wk(-1), sham iron infection 1wk(-1) and 105 mg of oral elemental iron daily; placebo group (n = 9), sham r-HuE PO injections 3wk(-1), sham iron injections 1wk(-1) and sham Iron tablets d aily. Each group was monitored during and for 4 weeks after drug administra tion. Results. Models incorporating combinations of the variables reticulocyte he matocrit (RetHct), serum EPO, soluble transferrin receptor, hematocrit (Hct ) and % macrocytes were analyzed by logistic regression. One model (ON-mode l) repeatedly identified 94-100% of r-HuEPO group members during the final 2 wk of the r-HuEPO administration phase. One false positive was recorded f rom a possible 189. Another model (OFF-model) incorporating RetHct, EPO and Hct was applied during the wash-out phase and, during the period of 12-21 days after the last r-HuEPO injection, it repeatedly identified 67-72% of r ecent users with no false positives. Interpretation and Conclusions. Multiple indirect hematologic and biochemic al markers used simultaneously are potentially effective for identifying cu rrent or recent users of r-HuEPO. (C) 2000, Ferrata Storti Foundation.