The Prognostic Significance of Beta2 Microglobulin in Patients with Hemophagocytic Lymphohistiocytosis

Objective. To determine the prognostic significance of beta2 microglobulin (β (2)-m) concentrations in patients with hemophagocytic lymphohistiocytosis (HLH), a rare disorder caused by pathologic activation of the immune system. Patients and Methods. The study population consisted of 74 patients diagnosed with HLH and 35 healthy controls. Serum β (2)-m levels were measured using a latex agglutination photometric immunoassay. Results. Median serum β (2)-m levels were significantly higher in HLH patients than in healthy controls (4.05 versus 1.5 mg/L; P < 0.001) and were significantly higher in patients with lymphoma associated hemophagocytic syndrome (LAHS) than in patients with benign disease-associated HLH (4.2 versus 3.3 mg/L; P < 0.001). Higher serum β (2)-m levels were positively correlated with LAHS (P = 0.005), abnormal lactate dehydrogenase concentrations (P = 0.009), and hypoalbuminemia (P = 0.003). ROC analysis showed that overall survival (OS) was significantly shorter in LAHS patients with serum β (2)-m levels ≥4.03 mg/L compared to <4.03 mg/L (P < 0.001). Moreover, multivariate analysis showed that serum β (2)-m level was an independent prognostic of OS (P = 0.034) in patients with LAHS. Conclusion. High serum β (2)-m levels and LAHS were associated with markedly poorer OS in patients with HLH. Serum β (2)-m concentration was a powerful and independent prognostic factor for OS in patients with LAHS.