[Macrophage activation syndrome disclosing leukemic transformation of mycosis fungoides].

BACKGROUND

Mycosis fungoides can mimic pigmented purpuric dermatitis. We report such a case which progressed to peripheral T-cell lymphoma; progression was revealed by reactive hemophagocytic syndrome (RHS).

METHODS

A 65-year old male patient was hospitalized for a pigmented and purpuric eruption. The skin lesions appeared 2 years earlier and at that time biopsy had shown pigmented and purpuric dermatitis. One month before hospitalization, general signs appeared. On admission, he had papular and purpuric rash, mainly on the trunk, hepatosplenomegaly, enlarged axillar and inguinal lymph nodes, and fever at 38.2 degrees. A skin biopsy showed histologic changes typical of mycosis fungoides. He also had bicytopenia, hepatitis, and increased triglyceride and ferritin levels suggesting RHS which was proved by means of bone marrow biopsy. These tests also evidenced peripheral T-cell lymphoma. The patient was treated with two courses of chemotherapy (CHOP) but the disease progressed and he deceased.

CONCLUSIONS

Mycosis fungoides can occasionally begin with an eruption very closely resembling pigmented purpuric dermatitis. Therefore, repeated biopsies should be done in case of widespread permanent pigmented purpuric dermatitis of no apparent origin. RHS is a life-threatening disease. The diagnosis should be suspected in any cytopenic patient with fever, increased triglyceride levels and abnormal liver tests. A search for an etiology must then be undertaken a prompt treatment is needed.