Rituximab for therapy-refractory cardiac sarcoidosis

In 2017 a caucasian 34 years old male presented to our outpatient clinic with generalized lymphadenopathy and mild restrictive lung defect and reduction in diffusion capacity. Diagnosis of sarcoidosis was made based on clinical presentation, radiological findings and histological examination of the lung parenchyma.

Two years before a cardioverter was implanted because of ventricular tachycardia after exclusion of coronary artery disease. Cardiological work-up revealed a mildly reduced ejection fraction of the left ventricle and increased metabolism of the myocardium in Cardio-PET-CT. Myocardial biopsy demonstrated an inflammatory myocarditis compatible with sarcoidosis. Corticosteroid therapy was started and escalated with azathioprine because of lacking clinical response. However, arrhythmia persisted and the patients complained palpations and exertional dyspnoea despite of antiarrhythmic and heart insufficiency therapy. A new Cardio-PET-CT scan demonstrated ongoing inflammation of the myocardium. Therefore, therapy was escalated to rituximab (two times 1 g within 14 days).Infliximab was avoided due to reduced ejection fraction and concerns of further deterioration of left ventricular function. Steroid dose was tapered during the following months without clinical complaints of the patients. At follow-up arrhythmia was reduced and a novel cardio-PET-CT showed markedly reduced inflammatory activity of the myocardium in line with a good response of sarcoidosis to rituximab treatment.

Immunosuppressive therapy in sarcoidosis is required in steroid-refractory sarcoidosis, however choice of the immunosuppressive drug relies mainly on trial and error and case severity. This case report emphasizes that rituximab may be an option for cardiac sarcoidosis, if other immunosuppressive drugs fail to induce remission or have to be avoided because of side effects.