Reticulocyte Count in Sports Medicine Physiological and Pathophysiological Principles

In clinical practice the reticulocyte count is the most useful method to estimate red cell life span and red cell production Formerly this was partly hampered by the low precision of manual counts Today this method is largely replaced by flow cytometry available by almost all larger systems for automated blood count ana lysis at low costs and sufficient analytic precision ibis methodology permits an extended use of the reticulocyte count in the differential diagnosis of anemias In pathological conditions resulting in anemia due to absolute or relative erythropoietin deficiency an increase of the reticulocyte count and a transient immaturity of the reticulocyte population is the first evidence of erythropoietic regeneration followed by a delayed increase of both the hemoglobin concentration and the he matocrit These clinical observations as well is experimental studies on healthy athletes performed after the Olympic Games in Australia in 2000 were used to create an indirect test to detect the use of blood doping in sports medicine particularly by the prohibited use of eivthropoietin and related medications before competitions However clinical experience shows frequent problems of the cor led interpretation of reticulocyte parameters due to v triable reporting of results and use of different calculations of reticulocyte indices Additional problems arise in doping controls such as the exact timing of the suspected use of erythropore tin and the blood tests performed as well as the possible influence of m physical strain per se Here we discuss the limits of the analytical methods and the problems of interpretation in the context of the laboratory profile in both the clinical setting and sports medicine