| Popis: |
Purpose: Two previous studies investigating the double-stranded DNA antibody titers in patients with familial Mediterranean fever found conflicting results. We intended to elucidate the reproducibility of the result revealed by one of these studies which found a high prevalance and correlation of double-stranded DNA antibodies with disease activity among a cohort of FMF patients. Methods: Double-stranded DNA antibody levels of 21 active FMF patients with 19 active lupus patients and 36 healthy volunteers as controls were determined with a commercial enzyme immunoassay kit. The sera of all subjects were also screened for antinuclear antibodies by using indirect immunofluorescent assay and substrates prepared from Hep-2 cell line. Results: Considering the cutoff value obtained by adding three standard deviations to the mean enzyme immunoassay value of healthy controls there was no significant increase in the double-stranded DNA values of active FMF patients compared to healthy controls. The percentage of fluorescent antinuclear antibodies in FMF group, healthy controls and lupus patients taken as positive controls were 23.8%, 8.3%, 100%, respectively. The fluorescence intensity was extremely weak in negative controls and in all FMF patients except one and could be defined as 'trace' when compared to that of lupus patients which was brightly luminiscent. Conclusion: The prevalance of double-stranded DNA antibodies has not increased and there were no significant difference between the percentage of fluorescent antibodies of FMF group and that of negative controls, although it appeared relatively high. This may be the result of female preponderance of our subjects, nonspecific binding of conjugate and subjective nature of the assay deciding in borderline situations. |
