Objective: To explore the significance of NK cell activity, interleukin-2 receptors (sCD(25)) and glycosylated ferritin in the early diagnostic of acquired hemophagocytic lymphohistiocytosis (HLH).
Methods: 57 patients suspected of HLH from June 2005 to May 2008 and 25 healthy subjects were enrolled in the study. The patients suspected of HLH were divided into three groups i.e. (1) a group with diagnosis confirmed at first visit; (2) a group with diagnosis confirmed at subsequent visit and (3) a group with diagnosis unconfirmed according to HLH-2004 diagnostic criteria. Healthy subjects were enrolled as control. NK cell activity was determined with a released LDH assay. The percentage of glycosylated ferritin was determined with phytohemagglutinin adsorption assay. sCD(25) was examined with ELISA double antibody sandwich assay. We compared the coincidence of each diagnostic index before and after diagnosis.
Results: The median percentage of NK cell activity was significantly lower in the first group (18.3 +/- 5.6)% and the second (16.7 +/- 6.7)% than that in the third group (33.4 +/- 6.8)% or in the controls (36.6 +/- 5.0)%. The median percentage of glycosylated ferritin was also significantly lower in the first group (15.4 +/- 2.0)% and the second group (16.9 +/- 3.4)% than that in the third group (40.4 +/- 3.0)% or in the controls (45.2 +/- 2.2)%. Meanwhile, the median level of sCD(25) was significantly higher in the first group (12 916 +/- 4328) ng/L and the second group (12 117 +/- 5465) ng/L than that in the third group (4728 +/- 1482) ng/L or in the controls (3841 +/- 993) ng/L. Furthermore, NK cell activity, sCD(25) and glycosylated ferritin were abnormal in all the patients in the early stage of HLH.
Conclusion: NK cell activity, sCD(25) and glycosylated ferritin may be helpful markers for the early diagnosis of HLH.