OBJECTIVETo investigate the expression levels and clinical significance of serum high mobility group box 1 (HMGB-1) in patients with secondary hemophagocytic lymphohistiocytosis (sHLH).

METHODSSerum HMGB-1 levels were determined by using enzyme linked immunosorbent assays (ELISA) in 51 sHLH patients and 15 healthy contrlols. Other laboratory data, including soluble interleukin-2 receptor (sCD25), white blood cells (WBC), hemoglobin (Hb), platelet (Plt), fibrinogen (FIB), lactate dehydrogenase (LDH), triglyceride (TG), alanine transaminase (ALT), aspartate aminotransferase (AST), serum ferritin (SF), C reactive protein (CRP), and blood sedimentation rate (ESR) were also collected.

RESULTSSerum HMGB-1 levels in the newly diagnosed group were significantly higher than that in the control group (P<0.01). Serum HMGB-1 levels in the newly diagnosed lymphoma-associated HLH (LHLH) group were significantly higher than that in non-HLH group, including infection-associated HLH (IHLH) and autoimmune-associated HLH (AHLH) group (P<0.05); The serum HMGB-1 levels in the clinical remission group were significantly lower than that in the newly diagnosed group (P<0.05), however, serum HMGB-1 was not decreased significantly in the progression/relapsed group, compared with the newly diagnosed group (P>0.05). Serum HMGB-1 levels in newly diagnosed sHLH patients positively correlated with sCD25 (r=0.62, P<0.01) and ESR (r=0.55, P<0.05). The receiver operating characteristic curves (ROC) for serum HMGB-1 levels of sHLH patients and healthy controls produced a cutoff value at 15.3 µg/L, with its 90% sensitivity and 99% specificity, respectively. In addition, an optimal cutoff value for HMGB-1 was 27.4 µg/L in the patients LHLH and non-HLH (AHLH+IHLH) with 96% sensitivity and 81% specificity, separately.

CONCLUSIONSerum HMGB-1 levels possesses an important clinically significance for disease diagnosis, differential diagnosis, evaluation of nosographic activity and treatment efficacy in the patients with sHLH.