Frequency of antinuclear antibodies and rheumatoid factor in healthy Turkish children. 
The frequency of antinuclear antibodies (ANA) and rheumatoid factor (RF) was investigated in 118 apparently healthy children (56 male, 62 female).  The mean age was 9.8+/-2.3 years.  Antinuclear antibodies (ANA) were detected by indirect immunofluorescence, using a Hep-2 cell substrate.  Nephelometry was used to quantify RF in 116 children.  Five serum samples (4%, 3M, 2F) were ANA-positive in low titers and all had a speckled pattern.  None of the ANA-positive children had other extractable antinuclear antibodies.  Rheumatoid factor (RF) was over 25 IU/ml in four children (3%, 3F, 1M).  None of these was positive for both antibodies.  Our results suggest a similar frequency of ANA in healthy Turkish children even with a Hep-2 cell substrate, when compared to results of other reports.  On the other hand, RF was more frequent than in other reported series.