Fulminant myocarditis with adult-onset Still's disease: case-based review

Myocarditis has been reported as a life-threatening complication of adult-onset Still's disease (AOSD), but fulminant myocarditis with AOSD is very rare. We hereby report a case of a 43-year-old female with fulminant myocarditis with AOSD. She had a refractory AOSD and cardiogenic shock with markedly elevated ferritin level up to 67,370 ng/mL. She was successfully treated with canakinumab and mechanical circulatory support (MCS) such as venoarterial extracorporeal membrane oxygenation and Impella CP. We also reviewed the previous cases of fulminant myocarditis with AOSD published from 1976 to December 2022, and only 8 cases of fulminant myocarditis with AOSD have been reported. The characteristics of these cases showed that the average age at presentation was 37.6 years (range 24-47 years). The time to myocarditis from the onset of AOSD ranged from 2 weeks to 2 years; however, most cases developed myocarditis within 1 year. Initial presenting symptoms included fever, dyspnea, chest pain, myalgia, rash, and sore throat. The median peak ferritin was 13,000 ng/mL. Left ventricular ejection fractions were not greater than 35%. Our case was the first reported case successfully treated with canakinumab and MCS. This review suggests that myocarditis may be an early phase of the complication in patients with AOSD, and the severity of AOSD may correlate with the severity of myocarditis. Canakinumab for AOSD and MCS for fulminant myocarditis may be one of the choices for overcoming the comorbidities.