The syndrome of the sea-blue histiocyte is a multisystemic infiltration by a special kind of macrophages which contain a ceroid material within its cytoplasm. We report herein a patient with mycosis fungoides, hyperlipidaemia type IIB and sea-blue histiocytes on bone marrow. Moreover, the cutaneous histopathology showed focus of eosinophilic spongiosis, that have not been previously described in mycosis fungoides, as far as we know.