Detection of anti-dsDNA antibodies by computer-aided automated immunofluorescence analysis.

INTRODUCTION

NOVA View is a computer aided fluorescence microscope that is used for the automated reading and interpretation of indirect immunofluorescent tests in diagnostic immunology. The objective of the present study was to evaluate the performance of the NOVA View® system for the measurement of anti-dsDNA antibodies using the Crithidia luciliae indirect immunofluorescence test (CLIFT) technology.

METHODS

Analytical performance of NOVA View CLIFT was assessed in repeatability (within run) and reproducibility (between runs and instruments) studies. Two hundred-fifty patient samples (N=200 consecutive samples and N=50 samples from systemic lupus erythematosus patients) were tested to evaluate the agreement between results generated with NOVA View CLIFT, and those obtained with manual microscopic reading of the same slides. Positivity rate in SLE was assessed on the 50 SLE samples.

RESULTS

The NOVA View system showed high level of repeatability and reproducibility within runs, between runs, and between instruments. Agreement of NOVA View software interpretation and digital image reading results with manual microscopic reading results was 96.0%, and the same positivity rate was obtained on SLE samples by NOVA View digital image reading as that of manual microscopic reading (36.0% vs. 38.0%, respectively).

CONCLUSION

Results generated by NOVA View CLIFT were equivalent to those obtained by manual microscopic reading on a large routine sample set. NOVA View demonstrated consistency within and between runs, and between instruments. Automation of CLIFT provides reliability and is a suitable alternative for routine clinical laboratories.