OBJECTIVETo explore significance of serum soluble CD163(sCD163) and soluble CD25(sCD25) in diagnosis and guiding treatment of children with hemophagocytic lymphohistiocytosis (HLH).

METHODData of 42 cases of children with HLH, 32 cases of non-HLH children with infection presented to First Affiliated Hospital of Zhengzhou University pediatric clinic and ward were collected from December 2013 to December 2014. Twenty-four healthy children were enrolled into a normal control group in the same period.Peripheral venous blood specimens (3 ml) were taken from the children with HLH after fasting before treatment, two weeks after treatment and eight weeks after treatment.Peripheral venous blood specimens (3 ml) were also taken from children of non-HLH infected group and normal control group after fasting at the initial visit. Serum sCD163 and sCD25 levels in the peripheral blood in three groups were determined by ELISA. According to cause of disease, children with HLH were divided into infection-related HLH, tumor-related HLH, primary HLH and others; relationship between serum sCD163 and sCD25 level and cause of disease was analyzed.

RESULTSerum sCD163 of HLH group ((6 094 ± 2 769) µg/L) and serum sCD163 of non-HLH infection group ((2 174 ± 950) µg/L) were significantly higher than that of normal control group ((777 ± 256) µg/L), F=71.396, P<0.05), and the differences among groups were statistically significant (P<0.05); serum sCD25 of HLH group ((41 963 ± 31 821) ng/L) and serum sCD25 of non-HLH infection group ((6 700 ± 4 105) ng/L) were significantly higher than that of normal control group ((2 440 ± 1 870) ng/L, F=37.513, P<0.05).There was no statistically significant difference between the non-HLH infection group with the normal control group (P>0.05), and the difference between the remaining groups was statistically significant (P<0.05). And serum sCD163 and sCD25 level of HLH group had a positive linear correlation, and Pearson correlation coefficient r=0.742 (t=7.000, P<0.05). The difference of serum sCD163 and sCD25 level among the different cause of disease in HLH group was significant (P<0.05).Pairwise comparison showed that serum sCD163 and sCD25 level of tumor-associated HLH group significantly increased as compared with infection-associated HLH group (P<0.05), but the difference was not statistically significant between the other groups (all P>0.05). Serum sCD163 and sCD25 level of HLH group before treatment, 2 weeks and 8 weeks after treatment showed a statistically significant tendency of decrease (P<0.05). Seen from the ROC curve, when sCD163 cut-off point was 2 359.08 µg/L, the diagnostic sensitivity was 83.3%, and specificity was 83.9%.When sCD25 cut-off point was 14 901.024 ng/L, the diagnosis sensitivity was 76.2%, and specificity was 98.2%.

CONCLUSIONSerum sCD163 and sCD25 levels may be used for diagnosis of HLH.Dynamically monitoring of serum sCD163 and sCD25 level can help to determine deterioration of HLH and guide treatment.