A novel prognostic model for adult patients with Hemophagocytic Lymphohistiocytosis

Abstract

Background

Hemophagocytic Lymphohistiocytosis (HLH) is a type of rare disease with low survival rate. We aimed to develop a model to evaluate the six-month prognosis in adult HLH patients. The data at discharge (will be called as post-treatment) for newly diagnosed adult HLH patients was collected and independent prognostic variables were selected for inclusion in the model.

Results

Three laboratory markers were confirmed to be the independent risk factors (ferritin: hazard ratio (HR) 0.101, 95% confidence interval (CI) 0.036–0.282, P<0.001; platelets: HR 4.799, 95% CI 1.884–12.223, P = 0.001; alanine aminotransferase (ALT): HR 0.423, 95% CI 0.180–0.997, P = 0.049). These were included in the final clinical prediction model. Receiver operating characteristic (ROC) curves disclosed that this model had a better discrimination (area under the curve (AUC) = 0.842, 95% CI 0.773–0.910, P < 0.001) than each of them alone and the calibration curves aligned completely with the model predictions and actual observations. Kaplan-Meier curves revealed a significant difference in the overall survival (OS) in patients stratified by the model with higher values associated with a better OS.

Conclusion

These results point out that serum ferritin, platelets and ALT levels are independent elements of OS in adult patients with HLH, and that the proposed model have a better prognostic value than any of these markers alone.