Elevated Serum Interleukin-6 Predicts Favorable Response to Immunosuppressive Therapy in Children With Aplastic Anemia

Background: Immunosuppressive therapy (IST) is the standard treatment for aplastic anemia (AA) children who lack a sibling donor, but the clinical response rate to IST varies. Predictors of response to IST are valuable for stratifying AA patients and making clinical decisions. Methods: The serum interleukin (IL)-6 levels of 41 AA patients were measured at the time of diagnosis and the response rate of the patients to IST was evaluated at 3, 6, and 12 months after IST. Receiver-operator characteristic (ROC) analysis was used to calculate the predictive value of initial IL-6 levels in determining response at 6 months after IST. Results: The initial IL-6 levels were significant higher in responders than nonresponders at 6 months after IST (211.89 vs. 18.09 pg/mL; P =0.005), using 36.8 pg/mL as a threshold, there were 80% sensitivity and 81% specificity for discriminating responders and nonresponders to IST. Patients with initial high IL-6 level (>36.8 pg/mL) have favorable response rates than those with initial low IL-6 level (<36.8 pg/mL) at 3, 6, and 12 months after IST ( P <0.01). Conclusion: High levels of IL-6 at the time of diagnosis predict a favorable response to IST in children with AA and this may be helpful for patient’s stratification and clinical decisions.