Does polycythemia affect interleukin‐6 response pattern in early postnatal period?

Abstract Introduction : Neonatal polycythemia may result in increased cytokine production. We aimed to investigate whether polycythemia and partial exchange transfusion (PET) affect interleukin‐6 (IL‐6) response pattern in early neonatal period. Methods : Ninety‐four newborns, 57 with polycythemia (Group 1) and 37 as control group (Group 2) were enrolled in the study. PET was performed at 4–6 hr following birth in the first group. Blood levels of IL‐6 were measured at 2–4 hr following birth; measurements were repeated at 6 and 24 hr after PET in newborns with polycythemia and at similar hours in Group 2. In Group 1, two patients (3.5%) who were diagnosed with proven sepsis excluded from the study. Results : Both initial and the last IL‐6 levels were higher in Group 1 (21.7; 5.5–190 pg/ml and 18.3; 2.7–92.4 pg/ml) than those of the controls (8.4; 0.2–47.8 pg/ml and 8.6; 2.0–21.0 pg/ml) ( P =0.001 for both comparisons). In Group 1, IL‐6 levels increased at 6 hr after PET and decreased thereafter. IL‐6 showed the same pattern in the control group. IL‐6 levels were higher than >70pg/ml in two (3.6%), seven (12.7%), and two (3.6%) subjects during three evaluation steps, respectively. Neither clinical nor proven sepsis was subsequently detected in any of these subjects. IL‐6 levels were within the acceptable values in Group 2. Conclusion : IL‐6 levels seem to be high in newborns with polycythemia during the first days of life, although they rarely exceed maximum acceptable levels. The pattern of IL‐6 response might be taken into account to optimize its use in the diagnosis of early‐onset neonatal sepsis. J. Clin. Lab. Anal. 24:340–347, 2010. © 2010 Wiley‐Liss, Inc.