Ye Q, , Wang G, et al. - This study sought to explore whether the exposure levels of mycophenolic acid are correlated with comorbidities in children with systemic lupus erythematosus. Researchers retrospectively obtained longitudinal data from systemic lupus erythematosus (SLE) children, who were taking mycophenolate mofetil for immunosuppression and under therapeutic drug monitoring. They computed the area under the concentration-time curve of mycophenolic acid (MPA) over 24 hours (AUC0–24h) with Bayesian methods. They used logistic regression and random forest models to evaluate the relationship between comorbidities and MPA exposure levels. Researchers enrolled 107 children with 358 times of follow-up (median age 169.02 months). It was shown that elevated levels of MPA exposure are correlated with decreased incidence odds of diabetes, acute kidney injury, or pneumonia in SLE children. The findings revealed that an AUC0–24h of 100.39 mg · h/L or an AUC0-12h of 50.20 mg · h/L could be used as the targeted exposure level for clinical practice.