IL2RA and hemophagocytic syndrome: Additional laboratory workup for HLH was notable for an elevated ferritin (1,684 ng/mL, reference range 31-294 ng/mL), elevated triglycerides (386 mg/dL, reference range 29-200 mg/dL), normal fibrinogen level (309 mg/dL, reference range 170-410 mg/dL), normal NK cell frequency and absolute count, and an elevated soluble IL-2R/CD25 (19,338 U/mL, reference range 137-838 U/mL).