[Lupus disease with antinuclear antibodies of the nucleolar type. Apropos of a series of 13 cases].

An exclusive or predominant nucleolar location of antinuclear antibodies is rare in the course of lupus disease: less than 1 p. cent of our patients. Thirteen cases of lupus disease with exclusive or predominant antinucleolar antibodies are analyzed: clinically, the only difference from other lupus diseases is the absence of pleurisy (p less than 0.03) and the frequent thrombopenia (p = 0.05). A proliferative glomerular lesion was found 4 times on renal biopsy. No patient presented any indications of overlapping sign with sclerodermia, polymyositis or Gougerot-Sjögren syndrome which are usually associated to a nuclear fluorescence of nucleolar type. 11 out of 13 patients have natural anti-DNA antibodies, including 9 with a very weak titer. Six patients present cytoplasmic anti-organic antibodies. Four patients have antibodies which precipitates on gelose, identifying nuclear or cytoplasmic antibodies: in 1 instance anti-SS-B et SS-A (Ro), in 1 instance anti-ribosomes associated with anti-ADN, in one instance anti-DNA. No serum contained anti-histones antibodies. The study of the sensitivity of nucleolar antigens to digestion by various enzymes (DNAse, RNAse and trypsin) showed that antinucleolar sera could be placed into three groups: 8/10 recognize a ribonucleic antigen, 1/10 a ribonucleoproteic antigen and 1/10 an antigen resisting to various enzymatic digestions. Therefore, in spite of its rarity, an exclusively nucleolar fluorescence should not rule out the diagnosis of lupus disease.