[Bullous amyloidosis].

The patient, a 75-year old man, was admitted in May, 1986 for separation of the epidermis and extensive ecchymotic patches. Physical examination showed numerous haemorrhagic erosions on the extensor aspect of the limbs, feet and hands, and wide patches of epidermal separation in the axillary and dorsal regions. Ecchymotic purpura was present on the limbs, abdominal wall, neck and right orbital region. Nikolsky's sign was positive at the periphery of the lesions. Epidermal cysts, 1 to 5 mm in diameter, were visible on the back of the hands and on the upper part of the neck. There was no macroglossia. Several biopsies were performed in both diseased and healthy skin. Light microscopy of the diseased skin showed, at the junction of the papillary and middle dermis, a band of eosinophilic deposit in which were true intradermal bullae containing red cells. Congo red and thioflavine T stainings were positive, forming a dermal band. At direct immunofluorescence IgG, IgA, IgM as well as the C3 and C9 components of complement were absent. At electron microscopy there was no bullous separation at the dermoepidermal junction; the dermal deposits had a dense amyloid-like fibrillar structure without ramifications. Laboratory examinations showed lambda-2 monoclonal gammopathy with normal levels of IgG and IgA and slightly decreased IgM. Bence-Jones protein was found in the ruin. Bone marrow examination showed 8 p. 100 plasmocytes. The diagnosis was: non myelomatous lambda-2 monoclonal dysglobulinaemia. Amyloid deposits were found in biopsies of the gums and rectum. Other investigations gave negative results. Bullous lesions have been reported in about 20 cases of primary amyloidosis.(ABSTRACT TRUNCATED AT 250 WORDS)