Major Infections of Newly Diagnosed Childhood-Onset Systemic Lupus Erythematosus.

Objective: To evaluate the risk of major infections in children with newly diagnosed childhood-onset systemic lupus erythematosus (cSLE). Methods: Predictors of major infections were identified by the multivariable logistic regression. Major infection free was defined as no major infection events within 6 months after the diagnosis of cSLE. The Kaplan-Meier survival plot was performed. A prediction model for major infection events was established and examined by receiver operating characteristic (ROC) curve analysis. Results: A total of 98 eligible patients were recorded in the medical charts. Sixty-three documented events of major infections were found in 60 (61.2%) cSLE patients. Furthermore, 90.5% (57/63) of infection events occurred within the first 6 months after the diagnosis of cSLE. The high SLEDAI (SLEDAI >10), lupus nephritis and lymphocyte count <0.8×109/L were predictors for major infections. The CALL score (Children with high disease activity [SLEDAI >10], lymphopenia, and LN) was defined by the number of predictors. Patients were then categorized into two groups: low-risk (score 0-1) and high-risk (score 2-3). Patients in the high-risk group had higher rates of the major infection occurrence than those in the low-risk group during the 6 months after the diagnosis of the cSLE (P<0.001) (HR:14.10, 95% CI 8.43 to 23.59). The ROC curve analysis indicated that the CALL score was effective both in the whole cSLE cohort [area under the curve (AUC) = 0.89, 95% CI: 0.81-0.97] and in the subgroup of lung infections (n = 35) (AUC = 0.79, 95% CI: 0.57-0.99). Conclusion: High disease activity, LN and lymphopenia were predictors for major infections in newly diagnosed cSLE patients. Specific predictors help identify the cSLE patients with the high risk of major infections. The CALL score could be a useful tool to stratify cSLE patients in practice.