Adult-Onset Still's Disease in Pregnancy: Lessons Learned and an Approach to Subsequent Pregnancies.

Adult-onset Still's disease (AOSD) is a rare autoinflammatory disorder with potential for life-threatening complications in pregnancy. Recently, biologic therapeutics have been increasingly used for treatment of AOSD, but there is little available data on the treatment of AOSD in pregnancy. Here we report a 23-year-old primigravid patient with a history of AOSD who presented at 20 weeks of gestation with fever, arthralgias, rash, fatigue, and highly elevated ferritin, concerning for AOSD flare. She was treated with tocilizumab, an interleukin-6 receptor antagonist, with rapid clinical and laboratory improvement; however, she underwent iatrogenic preterm delivery at 34 weeks of gestation for fetal distress, which was attributed to placental injury. In a subsequent pregnancy, she was treated with tocilizumab throughout and had an uncomplicated term delivery with normal labs and no AOSD flare. This case highlights that the use of tocilizumab may be effective to reduce the risk of AOSD flare during pregnancy.