Baseline characteristics
Table 1 displayed patients’ clinical characteristics and laboratory examination. The median age at diagnosis of total study population was 56 years and 23 patients (42.6%) were defined old patients (over 60 years). Male occupied a large proportion (70.4%), with ratio of 2.4. More than half (53.7%) suffered EBV infection. To be specific in terms of clinical manifestations, 54 patients (100%) presented with fever; 38 patients (70.4%) manifested with splenomegaly. Other laboratory findings of diagnostic criteria included hypofibrinogenemia (34/54), hypertriglyceridemia (26/54), hyperferritinemia (52/54) and hemophagocytosis (40/54).
The median level of 25-(OH)-D was 23.95 (range:7.5-90.8)ng/ml and 49 patients (90.7%)had vitamin D deficiency (25-(OH)-D<50nmol/L, i.e., 20ng/ mL). Then, we separated total cases into two groups according to a published research: low 25-(OH)-D level (n=32, <30 nmol/L) and relatively high 25-(OH)-D level (n=22, ≥30 nmol/L). Participants with lower 25-(OH)-D had higher TG (3.28vs. 2.45mmol/L P =0.032). There was no statistical difference on other characteristics. Patients in the high 25-(OH)-D group had a higher rate of hemophagocytosis, with a statistical trend (86.4% vs. 65.6% P =0.056).
According to the correlation analysis, the level of 25-(OH)-D was opposite to triglycerides and ferritin, with significant importance (Figure 1).