Prevalence of antinuclear autoantibodies in the serum of normal blood dornors.

Objective: To examine the presence of serum antinuclear autoantibodies in a healthy population.

Methods: Serum of 500 normal blood donors between 18 and 60 years of age were tested for the presence of autoantibodies. Antinuclear antibodies were detected by indirect immunofluorescence technique using HEp-2 epithelial cells as the substrate. The presence of dnaN was detected by indirect immunofluorescence technique using Critidia lucillae as the substrate. Anti-SSA (RO), anti-SSB (LA), anti-Sm, and anti-RNP were determined by double radial immunodiffusion.

Results: In the evaluation of the presence of serum antibodies, antinuclear antibodies were detected in 22.6% of the sera. The presence of other antibodies was not significant. The majority of the titers were 1:40.

Conclusion: The presence of autoantibodies is not necessarily pathologic and has to be related to the age group, gender, and clinical condition of the patient.