Cytophagic histiocytic panniculitis and hemophagocytic lymphohistiocytosis: an overview

Cytophagic histiocytic panniculitis (CHP) is a rare panniculitis that is associated with systemic features including fevers, hepatosplenomegaly, lymphadenopathy, pancytopenia, hepatic abnormalities, hypertriglyceridemia, and coagulopathy without an elevated erythrocyte sedimentation rate. The panniculitis lesions show adipose tissue lymphocytic and histiocytic infiltration along with hemophagocytosis, which may also appear in bone marrow, spleen, lymph nodes, and liver. Patients may have a rapidly fatal disease course, a longer disease course with intermittent remissions and exacerbations for many years prior to death, or a nonfatal acute or intermittent course responsive to treatment. The cytophagocytic disorder in these patients is a hemophagocytic lymphohistiocytosis (HLH), similar to the infection‐activated reaction associated with perforin mutations found in familial hemophagocytic lymphohistiocytosis. HLH is a group of autoinflammatory disorders, which include macrophage activation syndrome and infection‐associated hemophagocytic syndrome, which if not treated rapidly, can be fatal. The relationship of CHP and HLH is discussed. CHP associated diseases include: subcutaneous panniculitis‐like T cell lymphomas; infections, connective tissue diseases, other malignancies, and the molecular disorders that cause HLH. Treatment of CHP includes: glucocorticoids in combination with cyclosporine, combined chemotherapeutic medications and most recently, anakinra, an Interleukin‐1 receptor antagonist; along with supportive care, search for underlying malignancies and treatment thereof, and control of associated infections.