We report a case of erythroderma revealing lymphoblastic leukaemia occurring immediately after myelodysplasia. The patient was an 87-year old man admitted for poor general condition, lymph node enlargement and pruriginous oedematous erythroderma. Laboratory examinations showed tricytopenia, bone marrow invasion by lymphoblasts in a myelodysplastic environment of the refractory anaemia type with excess of blasts, and a cutaneous lymphocytic infiltrate with non-blastic lymph node reaction. Owing to its morphological and immunohistological features, the lymphocytic infiltrate was regarded as non-specific. We could not help comparing this case to the other non-specific cutaneous lesions of refractory anaemia which usually reflect transformation into leukaemia.