Objectives To evaluate if the existence of anti-dsDNA antibodies detected by Crithidia luciliae indirect immunofluorescence (CLIF) method is associated with clinical and laboratory differences in patients with recent diagnosis of SLE.
Methods Retrospective descriptive study of a group of 104 SLE patients (who fulfilled the ACR 1982 revised criteria) with diagnostic and follow-up in our center. After consulting the clinical histories of the patients we recorded and analyzed: demographic data (age, sex and race), clinical manifestations (articular and extra-articular like malar rash, photosensitivity, discoid lupus, oral ulcers, diffuse alopecia, serositis, neurological, hematological and renal involvement) and laboratory parameters (ESR-mm/h, PCR-mg/dl, C3-mg/dl, C4-mg/dl, DNA-UI/mL, ANA titer, leukocyte, lymphocyte and neutrophil count-x10^3/ul, 24 hour proteinuria-mg/24h). We divided the patients in 3 groups based on the presence of anti-dsDNA by CLIF as follows: Group 1-CLIF always negative, Group 2-positive for CLIF at baseline, Group 3-positive for CLIF sometime during follow-up.
Results Of the 104 patients analyzed 97.1% were women with a mean age at the time of the diagnosis of 42,1±15,4 years. Twenty-nine patients (27.9%) were positive for anti-dsDNA CLIF at baseline (group 2) and 12 (11.5%) during follow-up (group 3). The patients who were positive for anti-dsDNA by CLIF at baseline showed higher titers of anti-dsDNA by ELISA and ANA antibodies, more lymphopenia and complement consumption, statistically significant when compared with the other two groups (p< 0.05). Regarding the clinical manifestations, the patients positive for anti-dsDNA by CLIF (groups 2 and 3) presented with more arthritis at baseline (p = 0.005). (see table).
Conclusions The results of this study suggest that the patients with SLE with positive anti-dsDNA by CLIF have more active disease presenting more lymphopenia and complement consumption. In our study population the baseline and follow-up positivity for anti-dsDNA by CLIF was associated to more arthritis at the beginning of the disease.
Acknowledgements Sergi Mojal
Disclosure of Interest None Declared