Agreement of three commercial anti-extractable nuclear antigen tests: EUROASSAY Anti-ENA Profile, Polycheck Autoimmune Test and FIDISConnective Profile

Antinuclear antibody (ANA) is useful in the diagnosis of connective tissue disorder (CTD). Association of specific autoantibodies with the immunofluorescence pattern of ANA in CTD, noted in western literature has been considered as reference in all over the world. However, in Bangladesh no such research work or data correlating the autoantibodies and their ANA patterns is found. Objective of the study was 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 CTD patients. Serum samples of 152 CTD patients (Systemic lupus erythematosus, Rhumatoid arthritis, Sjogren´s syndrome, Systemic sclerosis, Polymyositis, Mixed connective tissue disease) were diagnosed clinically, attending at Bangabandhu Sheikh Mujib Medical University (BSMMU) during the study period of January, 2010 to December, 2010. Samples were subjected for ANA testing by Indirect Immunofluorescence (IIF) on HEp-2 cell (ALPHADIA) in dilution of 1:40, 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, anti-SSB/La, anti-Scl-70 and anti-Jo-1. Out of 152 patients 110 (72.3%) cases were ANA positive by IIF on HEp-2 cell. ANA positive sera exhibited four fluorescence patterns such as speckled (50.8%), peripheral (21.6%) ,homogenous (18.1%) and nucleolar pattern (9%). Peripheral pattern and homogenous pattern was predominantly associated with anti-dsDNA (p<0.05). Speckled pattern was significantly associated with anti-ENA (p<0.05).The most commonly identified antinuclear autoreactivity was directed towards anti-RNP (25.7%) then anti-Scl-70 (20%), anti-SSA (14.2%) and anti-SSB (5.7%). Multiple anti-ENA reactivities were identified in 34.28% cases. Peripheral and homogenous pattern is strongly associated with anti-dsDNA and speckled pattern may predict anti-ENA (specially ribonucleoprotiens). As a definite correlation between the ANA patterns and the group of antibodies was detected by dot immunoblot, one could predict presence of certain specific auto antibodies for a particular ANA pattern identified. This may restrict on the cost of laboratory investigations in a developing country like Bangladesh. Thus, ANA-IIF method may reduce the expense of detailed immunological work-up with minimal loss in diagnostic accuracy.Bangladesh Med Res Counc Bull 2014; 40 (2): 74-78

Download Full-text

O38 A study on correlation of the Extractable Nuclear Antigen with clinical presentation and severity in patients of various connective tissue disorders

Indian Journal of Rheumatology ◽

10.1016/s0973-3698(10)60613-9 ◽

2010 ◽

Vol 5 (3) ◽

pp. S12

Author(s):

Viren Kaul

Keyword(s):

Connective Tissue ◽

Clinical Presentation ◽

Nuclear Antigen ◽

Connective Tissue Disorders ◽

Extractable Nuclear Antigen

Download Full-text

Diagnostic accuracy of the FIDIS multiplex fluorescent microsphere immunodetection system for anti-extractable nuclear antigen (ENA) antibodies in connective tissue diseases

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm.2007.096 ◽

2007 ◽

Vol 45 (4) ◽

Cited By ~ 12

Author(s):

Martine Vercammen ◽

Patricia Meirlaen ◽

Jacques Sennesael ◽

Brigitte Velkeniers ◽

Sara T'Kint ◽

...

Keyword(s):

Connective Tissue ◽

Diagnostic Accuracy ◽

Connective Tissue Diseases ◽

Nuclear Antigen ◽

Fluorescent Microsphere ◽

Extractable Nuclear Antigen

AbstractClin Chem Lab Med 2007;45:505–12.

Download Full-text

Application of a Combined Protocol for Rational Request and Utilization of Antibody Assays Improves Clinical Diagnostic Efficacy in Autoimmune Rheumatic Disease

Archives of Pathology & Laboratory Medicine ◽

10.5858/2007-131-112-aoacpf ◽

2007 ◽

Vol 131 (1) ◽

pp. 112-116

Author(s):

Marilina Tampoia ◽

Vincenzo Brescia ◽

Antonietta Fontana ◽

Antonietta Zucano ◽

Luigi Francesco Morrone ◽

...

Keyword(s):

Rheumatic Disease ◽

Clinical Pathology ◽

Nuclear Antigen ◽

Pathology Laboratory ◽

Diagnostic Efficacy ◽

Diagnostic Protocol ◽

Autoimmune Rheumatic Disease ◽

Double Stranded Dna ◽

Extractable Nuclear Antigen ◽

Dna Antibodies

Abstract Context.—Because of a marked increase in the number of requests for antinuclear antibodies, anti–extractable nuclear antigen antibodies, and anti–double-stranded DNA antibodies for the diagnosis of autoimmune rheumatic disease, guidelines have been proposed for their appropriate use. Objective.—To evaluate in terms of clinical efficacy and cost-benefit ratio the outcome of applying a protocol for the diagnosis of autoimmune rheumatic disease. Design.—A diagnostic protocol for the rational utilization of second-level tests (anti–extractable nuclear antigen antibodies and anti–double-stranded DNA antibodies) was applied at Hospital Polyclinic beginning January 2004. The appropriateness of 685 consecutive requests received at the clinical pathology laboratory from January to June 2004 was assessed. Patients who underwent these laboratory tests were followed up for 12 months after blood sample drawing. Results.—Introduction of the protocol led to a significant reduction in the number of second-level tests prescribed (27.9% vs 49.5% for anti–extractable nuclear antigen antibodies; 27.5% vs 56.6% for anti–double-stranded DNA antibodies). After the period of observation, none of the 163 patients who had negative results on the first-level test and were asymptomatic, for whom second-level tests had not therefore been performed, were found to have autoimmune rheumatic disease. In 90.5% (77/85) of patients positive for the second-level tests, clinical confirmation of autoimmune rheumatic disease was obtained. Conclusions.—Not only did application of the diagnostic protocol reduce the number of second-level tests performed but it also increased their specificity. Our data thus indicate that the use of shared guidelines by clinical and laboratory specialists yields satisfactory results.

Download Full-text