Hemophagocytic lymphohistiocytosis: a rare complication of autologous stem cell transplantation.

Hemophagocytic lymphohistiocytosis (HLH) is a very severe and rare syndrome of pathologic immune activation characterized by cytopenia and clinical signs and symptoms of extreme inflammation. HLH is usually fatal without treatment so that accurate and timely diagnosis is very important. The syndrome occurs as a familial disorder (familial HLH - FLH) or as an acquired condition (secondary - sHLH) in association with a variety of pathologic states: infections, rheumatologic, malignant or metabolic diseases. Malignancy associated HLH is primarily reported in T÷NK (natural killer)-cell malignancies but also in B-cell neoplasms and other types of cancer. HLH has also been reported in rare cases as a highly fatal and difficult to diagnose complication of stem cell transplantation (SCT). In this paper, we present the case of a young male patient who underwent autologous SCT as consolidation therapy for a T÷NK-cell lymphoma, complicated with graft failure due to HLH. The patient was successfully treated with corticosteroids, Etoposide, Cyclosporine and immunoglobulins. As a particularity, he developed a second B-cell neoplasia a few months after SCT.