Leukocyte, neutrophil, immature granulocyte counts and interleukin-6 are superior to procalcitonin, C-reactive protein and delta-He for detection of mild inflammation: data from marathon runners producing mild systemic inflammation visible immediately after the run / Leukozyten, Neutrophile, unreife Granulozyten und Interleukin-6 sind zum Nachweis geringgradiger Entzündungen Procalcitonin, C-reaktivem Protein und Delta-He überlegen: Ergebnisse aus einer Untersuchung von Marathonläufern

Immature granulocytes (IGs) and differences between reticulocyte and erythrocyte haemoglobin content (delta-He) are now available as modern parameters on routine haematology analysers for detecting inflammation. Are these markers more suitable to detect mild inflammation when compared with traditional inflammation markers such as leukocyte count, C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 (IL-6) or diverse leukocyte surface molecules mainly used in research programs? To answer this question, a marathon race was used as a model of mild inflammation. Full blood counts, CRP, PCT, IL-6, expression of surface molecules on granulocytes, monocytes and lymphocytes were measured before and immediately after the race (inflammatory state) and were compared with each other. A further blood sample was taken after a 10-day rest. In the inflammatory state leukocytes, neutrophil counts and IL-6 concentration were considerably increased compared with basic conditions. Diagnostic sensitivity and specificity came up to 100%. CRP was not increased and delta-He did not drop to negative values, as it occurs in severe inflammation. Leukocyte surface molecules were able to indicate a mild inflammatory state induced by the marathon race, but these markers did not achieve the same discriminatory power when compared with IL-6 levels or neutrophil count. In conclusion, leukocytes, neutrophils and IG counts as well as IL-6 levels are the best indicators in a mild inflammation model similar to a marathon race.