Elevated Interleukin-10 Levels Are Associated with Low Platelet Count and Poor Prognosis in 90 Adult Patients with Hemophagocytic Lymphohistiocytosis.

INTRODUCTION

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening syndrome characterized by excessive inflammatory responses. This study explored the association between laboratory characteristics and outcomes in adult patients with HLH.

METHODS

The adult patients diagnosed with HLH at the Second Hospital of Shanxi Medical University from September 2016 to September 2021 were retrospectively analyzed in this study.

RESULTS

A total of 90 HLH patients were included. Among them, 60% were males, with a median age at diagnosis of 54 years. More than 85% of HLH patients presented with fever, splenomegaly, and cytopenias. IL-10 and IL-6 were elevated in 93.3% and 91.1% of patients, respectively. Elevated IL-10 levels were associated with lower platelet counts (r = -0.37, p < 0.001). Infections were seen in 46.7% (42/90) of cases. 29 patients with malignancy-associated HLH had T- or NK-cell (n = 16) or B-cell (n = 12) lymphoma. Autoimmune diseases accounted for 21.1% (19/90). Treatment was variable. In total, 36 patients survived (40%). The median overall survival (OS) was 1.5 months (95% confidence intervals [CI]: 0.2-2.8 months), with a 1-year OS of 40.9%. Patients with autoimmune diseases had markedly longer survival than those triggered by infection and malignancy (p < 0.001). Multivariate Cox regression analysis indicated that treatment delays (hazard ratios 0.36, 95% CI: 0.14-0.94, p = 0.036), platelet count (2.33, 1.30-4.18, p = 0.005), and IL-10 (2.07, 1.16-3.68, p = 0.014) were independent risk factors for poor outcome.

CONCLUSION

Infection and lymphoma are the leading causes of HLH in adult patients with heterogeneous clinical manifestations. Survival of adult HLH is frustrating, especially those associated with malignancies. Besides, elevated IL-10 levels were associated with lower platelet counts, and these two markers were independent risk factors for poor prognosis. Earlier treatment led to better outcomes.