SummaryDescription of a typical case of acute disseminated lupus erythematosus with signs and symptoms of diffuse involvement of the skin, articulations, heart, lungs, kidneys and central nervous system.The histological study showed most of the characteristic lesions associated with this disease : hematoxylin bodies, periarterial fibrosis of the spleen, retinal cytoid bodies and«wire loop»glomeruli of the kidneys. This last change does not seem to differ greatly from the other types of glomerular hyalinosis.The results of the cytochemical study of the hematoxylin bodies agree with those of Klemperer and coworkers. These corpuscules could arise from the depolymerization of desoxyribonucleins of the connective cells, and perhaps also from their subsequent combination with a protein of the ground substance of the connective tissue.Most of the changes observed were not extensive, except in the skin. This contrasted strikingly with the severity of the clinical course. However, the persistent fall of serumalbumin along with the considerable increase of gammaglobulins, indicated a profound disturbance in the protein metabolism.