Cytophagic histiocytic panniculitis with haemophagocytosis in a patient with familial multiple lipomatosis and review of the literature.

We report a patient with the extremely rare familial multiple lipomatosis syndrome, who developed the uncommon autoimmune disease cytophagic histiocytic panniculitis, manifested as inflammation of preexisting lipomas. Despite his initial critical condition and unsuccessful treatment with steroids, he responded to cyclosporin and remains well 15 years after diagnosis. In contrast with most previous reports, our patient stays dependent on cyclosporin; repeated attempts of discontinuing or substituting treatment were quickly followed by relapse. Haemophagocytic panniculitis is considered as a T-cell disorder, but its exact pathophysiological mechanism has not been clarified. Differential diagnosis of cytophagic histiocytic panniculitis mainly includes malignant histiocytosis, subcutaneous panniculitis-like T-cell lymphoma (SPTCL) and lupus erythematosus panniculitis (lupus profundus). We discuss the main clinical features, diagnostic challenges and treatment issues of this usually benign, but at times life-threatening autoimmune condition.