Clinical features of 39 patients with antibodies to extractable nuclear antigens despite negative antinuclear antibodies: evidence for autoimmunity including neurologic and connective tissue diseases.
Systemic lupus erythematosus (SLE) rarely presents with a negative antinuclear antibody (ANA). Although antibodies to extractable nuclear antigens (ENA) are sometimes ordered despite a negative ANA, it is unclear if this contributes to the diagnosis of SLE or other forms of connective tissue disease (CTD). We reviewed 39 patients with anti-ENA antibodies despite a negative ANA during a 1-year period to determine the presence of SLE or other CTD. Several patients had clinical features suggestive of CTD, including 1 with possible SLE. A number of patients had neurologic disorders, especially peripheral neuropathy. In this study, the finding of anti-ENA despite negative ANA was associated with neurologic disorders and CTD. This may represent test bias or false-positive anti-ENA assays or false-negative ANA assays, or may imply immune-related mechanisms not previously described.
Davis
John M
JM
From Division of Rheumatology (JMD, KGM, SRY), Department of Medicine; Division of Clinical Biochemistry and Immunology (HAH), Department of Laboratory Medicine and Pathology; Mayo Clinic College of Medicine and Mayo Clinic, Rochester, Minnesota.
Moder
Kevin G
KG
Homburger
Henry A
HA
Ytterberg
Steven R
SR
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies / Q000032:analysis*; D000974:Antibodies, Antinuclear / Q000032:analysis*; D034961:Antigens, Nuclear / Q000276:immunology*; D015551:Autoimmunity / Q000276:immunology*; D015331:Cohort Studies; D003240:Connective Tissue Diseases / Q000175:diagnosis / Q000276:immunology*; D003937:Diagnosis, Differential; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000276:immunology*; D010523:Peripheral Nervous System Diseases / Q000276:immunology; D012859:Sjogren's Syndrome / Q000175:diagnosis / Q000276:immunology
D000906:Antibodies; D000974:Antibodies, Antinuclear; D034961:Antigens, Nuclear