Hemophagocytic Lymphohistiocytosis Complicating Systemic Sarcoidosis.

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening hyperinflammatory syndrome characterized by histiocyte proliferation and hemophagocytosis. Primary HLH is caused by genetic defects, whereas secondary HLH occurs in the setting of underlying diseases, such as infections, malignancies, or rheumatic diseases. Rheumatic diseases, such as systemic juvenile arthritis or systemic lupus erythematosus, have been associated with HLH. However, the association between sarcoidosis and HLH has been rarely reported in the literature. Herein, we report a case of a 36-year-old female who was recently diagnosed with sarcoidosis, and she developed fatal HLH that was not responsive to high-dose steroids.