Frequency of antinuclear antibodies in healthy children and adolescents.

Sera from 214 healthy children and adolescents (108 females [50.4%]) aged 6 months to 20 years (mean 8.7 years) and from 116 patients with rheumatic diseases were assayed for antinuclear antibody (ANA) by indirect immunofluorescence (IIF) by using HEp-2 cells as substrate. Twenty-seven healthy children (12.6%) presented a positive ANA test; there was no difference between genders, and we observed a trend for higher frequency of ANA >/= 1/80 among children between 5 years and 10 years. Eight of the 27 healthy children with positive ANA test were reevaluated 36 months later, and none of them had developed any rheumatic disease, though the sera remained positive in 2 of them. ANA was present in 42/116 patients (36.2%). In daily medical practice ANA determination should be required only in individuals with clinical signs and symptoms suggestive of autoimmune disease.