Evaluation of an Automated Screening Assay, Compared to Indirect Immunofluorescence, an Extractable Nuclear Antigen Assay, and a Line Immunoassay in a Large Cohort of Asian Patients with Antinuclear Antibody-Associated Rheumatoid Diseases: A Multicenter Retrospective Study

We assessed the diagnostic utility of the connective tissue disease (CTD) screen as an automated screening test, in comparison with the indirect immunofluorescence (IIF), EliA extractable nuclear antigen (ENA), and line immunoassay (LIA) for patients with antinuclear antibody- (ANA-) associated rheumatoid disease (AARD). A total of 1115 serum samples from two university hospitals were assayed using these four autoantibody-based methods. The AARD group consisted of patients with systemic lupus erythematosus (SLE), systemic sclerosis (SSc), Sjögren’s syndrome (SS), and mixed connective tissue disease (MCTD). The qualitative results of all four autoantibody assays showed a significant association with AARDs, compared to controls (P<0.0001 for all). The areas under the receiver operating characteristic curves (ROC-AUCs) of the CTD screen for differentiating total AARDs, SLE, SSc, SS, and MCTD from controls were 0.89, 0.93, 0.73, 0.93, and 0.95, respectively. The ROC-AUCs of combination testing with LIA were slightly higher in patients with AARDs (0.92) than those of CTD screen alone. Multivariate analysis indicated that all four autoantibody assays could independently predict AARDs. CTD screening alone and in combination with IIF, EliA ENA, and LIA are potentially valuable diagnostic approaches for predicting AARDs. Combining CTD screen with LIA might be effective for AARD patients.

The Child as a Surrogate for Diagnosis of Lupus in the Mother

Introduction. Neonatal lupus erythematosus (NLE) is an acquired disease of the newborn caused by transplacental transfer of maternal anti-Ro/SSA, anti-La/SSB, and infrequently anti-U1 RNP antibodies. Methodology. This is a case report of a male infant delivered via Caesarean section at 36-week gestation following detection of fetal bradycardia during routine antenatal clinic visit. Results. The mother was seropositive for antinuclear antibody (ANA) and anti-Ro/SSA and had elevated erythrocyte sedimentation rate. The baby was positive for ANA, extractable nuclear antigen (ENA), and anti-Ro/SSA. Pediatric echocardiography was abnormal and electrocardiography confirmed complete heart block.

Immunofluorescence pattern of antinuclear antibody and its association with autoantibody profile in systemic lupus erythematosus

<p><strong>Background:</strong> Antinuclear antibody (ANA) is useful in the diagnosis of systemic lupus erythematosus (SLE). Association of specific autoantibodies with the immunofluorescence pattern of ANA in SLE as noted in Western literature has been taken as reference in all over the world. However, in Bangladesh such research work or data correlating the autoantibodies and their ANA patterns is inadequate. <strong></strong></p><p><strong>Objective:</strong> To identify an association between immunofluorescence patterns of antinuclear antibody on HEp-2 cell and more specific antinuclear reactivities (e.g. anti-dsDNA and anti-extractable nuclear antigen) in the serum samples of SLE patients.</p><p><strong>Methods:</strong> Serum samples of 37 SLE patients who were diagnosed by ARA (American Rheumatism Association) classification criteria and laboratory tests, attending at lupus clinic of Bangabandhu Sheikh Mujib Medical University (BSMMU) during the study period of six months were subjected for ANA testing by Indirect Imrnunofluorescence (IIF) on HEp-2 cell, anti-dsDNA by ELISA and anti- extractable nuclear antigen (anti-ENA) by Dot Immunoblot. Dot blot strips were tested for anti-Sm, anti-RNP, anti-SSA/Ro, and anti-SSB/La. <strong></strong></p><p><strong>Results:</strong> Out of 37 SLE patients 32 (86.5%) cases were ANA positive by IIF on HEp-2 cell. ANA positive sera exhibited three fluorescence patterns such as speckled (43.7%), peripheral (34.3%) and homogenous pattern (21.8%). Peripheral pattern (100%) was strongly associated with anti-dsDNA (p&lt;0.05) and homogenous pattern (85.7%) was also predominantly associated with anti-dsDNA (p&lt;0.05). Speckled pattern (85.6%) was significantly associated with anti-ENA (p&lt;0.05). Anti-dsDNA was positive in 75% of SLE cases and majority (45.8%) of which showed peripheral pattern whereas anti-ENA was positive in 48.6% cases and majority (70.5%) of which showed speckled pattern. The most commonly identified antinuclear autoreactivity was directed towards anti-RNP (22.2%) then anti-Sm (16.6%), anti-SSA (16.6%) and anti-SSB (11.1 %). Multiple anti-ENA reactivities were identified in 33.3% cases. <strong></strong></p><p><strong>Conclusion:</strong> Peripheral and homogenous pattern is strongly associated with anti-dsDNA therefore may be predicted that patients have active SLE and speckled pattern may predict anti-ENA (specially ribonucleoprotiens). Thus, ANA-IIF method may suffice and probably reduce the expense of detailed immunological work-up with minimal loss in diagnostic accuracy.</p>