Uncommon antinuclear antibody patterns as diagnostic indicators.

INTRODUCTION

The clinical significance of common antinuclear antibody (ANA) patterns, such as nuclear homogenous and nuclear speckled patterns with their corresponding specific antibodies, has already been established. However, the clinical relevance of these uncommon ANA patterns have not been well elucidated and these patterns are therefore not reported by most clinical laboratories. We herein report some retrospective data analysis linking patients' clinical status to several uncommon ANA patterns.

METHODS

We retrieved and assessed the patient records for ANA reports generated in our hospital over a period of two years. All testing had been performed using the gold standard Indirect Immunofluorescence Assay.

RESULTS

Records of 1235 consecutive patients tested for ANA were reviewed. ANA was positive in 330 of these patients with 6.39% found to have uncommon nuclear, cytoplasmic or mitotic sub-patterns. The mitotic spindle (0.89%), cytoplasmic anti-mitochondrial antibodies (0.80%), followed by discrete nuclear dots-multiple (0.72%) were the dominating patterns, with a higher prevalence in females than in males. Systemic lupus erythematosus and rheumatoid arthritis were the two most common autoimmune disorders associated with mitotic spindle fibers and nuclear centromere and nuclear large/coarse speckled ANA patterns.

CONCLUSION

The prevalence of these relatively uncommon ANA patterns was higher than expected. Further evaluation of these patterns along with their corresponding antibodies and their clinical utility must be encouraged. We trust this endeavour will provide diagnostic information in autoimmune and other disease conditions.