[Antibodies against native deoxyribonucleic acid (anti-nDNA) without antinuclear antibodies: clinical significance (author's transl)].

Antinuclear antibodies (ANA) by indirect immunofluorescence and antibodies against native deoxyribonucleic acid (anti-nDNA) by radiommunoassay were measured simultaneously in 6,000 sera from about 5,000 patients. Usual findings about 5,000 patients. Usual findings were: (a) both tests negative (75%), (b) only ANA positive (20%), and (c) both tests positive (3%). The unusual combination of ANA-negative/anti-nDNA positive was found in 117 sera from 24 patients. These patients were examined more closely clinically and the mentioned tests repeated. In five with systemic lupus erythematosus, in two with chronic rheumatoid arthritis and one with chronic urticaria this finding occurred repeatedly over some time. In five additional patients (two with chronic hepatitis, one each with drug-induced systemic lupus erythematosus, chronic rheumatoid arthritis, and drug related haemolytic anaemia) this unusual finding occurred only once but with high levels of anti-nDNA. In 11 patients with various diseases the combination of ANA-negative/anti-nDNA positive occurred only once, with the anti-nDNA value being low. In a control group of patients with mononucleosis, cytomegalic disease, acute or chronic hepatitis or hepatoma, anti-nDNA results were never positive.