Cytophagic Histiocytic Panniculitis

Cytophagic histiocytic panniculitis (CHP) is a very rare form of panniculitis manifesting as recurrent multiple subcutaneous nodules (which may progressively become ecchymotic and ulcerated), and histologically characterized by lobular panniculitis with lymphocytic and histiocytic infiltration in the subcutaneous adipose tissue.

Epidemiology

The exact prevalence is unknown, but less than 100 cases have been reported (mostly middle-aged and elderly patients).

Clinical description

The histiocytic infiltration often involves lymph nodes, bone marrow and other tissues of the reticuloendothelial system. Severe fever, malaise, pancytopenia, hepatosplenomegaly, and mucosal ulcers are common systemic symptoms.

Etiology

The etiology remains unclear. In more than 50% of cases, the disease occurs in immunocompromised patients (those with immunodeficiency, autoimmune disease or hematological disease) and is triggered by an infection (mainly with a virus from the herpes-virus family).

Diagnostic methods

Diagnosis relies on the histological features of fat infiltration.

Differential diagnosis

Differential diagnosis includes malignant histiocytosis and virus-associated hemophagocytic syndrome, as well as systemic Weber-Christian panniculitis (see these terms). A search for subcutaneous T-cell lymphoma is mandatory.

Management and treatment

Management involves symptomatic treatment and systemic chemotherapy. Combinations of cytotoxic and immunosuppressive drugs have been reported to be efficient. Chemotherapy followed by stem cell rescue should be considered in severe cases.

Prognosis

Although remissions have been reported, the disease tends to follow a chronic course often complicated by terminal hemorrhagic diathesis and organ system failure.