Bullous pemphigoid (BP) is an autoimmune blistering skin disease. Autoantibodies to BP180 and BP230 can be detected by indirect immunofluorescence (IIF) on different substrates (oesophagus, salt-split-skin, BP180-antigen dots, BP230-transfected cells) and ELISA. Here, we compared test characteristics of these test systems. We analysed sera from BP patients (n=60) in whom the clinical diagnosis had been confirmed histopathologically. The control cohort comprised sera from patients with other autoimmune-associated (n=22) or inflammatory (n=35) skin diseases. All samples were tested by IIF (EUROIMMUN™ Dermatology Mosaic) and ELISA (EUROIMMUN and MBL). Anti-BP180 is best detected with BP180-antigen dots by IIF (sensitivity: 88%; specificity: 97%). As
compared to IIF, the differences with both BP180 ELISA techniques are small though. Likelihood ratios (LRs) for positive and negative test results are >10 and between 0.1 and 0.2, respectively, for all test systems. Detection of anti-BP230 is highly variable (sensitivity range 38-60%; specificity range 83-98%). Only the IIF test reveals a LR for positive test results >10. Since the LRs for a negative test are all ~0.5, negative test results for anti-BP230 antibodies do not help to exclude BP. In conclusion, the multi-parameter IIF test reveals a good diagnostic performance in BP. Since this test simultaneously allows for the detection of anti-Dsg1 and anti-Dsg3 antibodies, involved in pemphigus foliaceus and vulgaris, a single test-incubation may be sufficient to differentiate between the most frequent autoimmune blistering diseases.
In conclusion, the multi-parameter IIF test reveals a good diagnostic performance in BP. Since this test simultaneously allows for the detection of anti-Dsg1 and anti-Dsg3 antibodies, involved in pemphigus foliaceus and vulgaris, a single test-incubation may be sufficient to differentiate between the most frequent autoimmune blistering diseases. PMID: 22580378 [PubMed – in process] (Source: Journal of Immunological Methods)
from MedWorm: Pemphigus http://www.medworm.com/index.
Systematic reviews and meta-analysis are essential tools to accurately and reliably summarize evidence, and can be used as a starting point for developing practice guidelines for the diagnosis and treatment of patients.
To estimate the diagnostic accuracy of enzyme-linked immunosorbent assays (ELISA) to detect anti-BP180 and anti-desmoglein 3 (Dsg3) autoantibodies in the diagnosis of autoimmune blistering skin diseases.
A Medline search of English written articles, published between 1994 and 2011, reporting data on the sensitivity and specificity of diagnostic tests was conducted using the following search terms: “BP180 autoantibodies”, “Dsg3 autoantibodies”, and “enzyme linked immunosorbent assay”. The selected articles have been evaluated according to the quality of the statistical methods used to calculate diagnostic accuracy (definition of cutoff value, use of ROC curves, and selection of control cases). The meta-analysis was performed using a summary ROC (SROC) curve and a random-effect model to independently combine sensitivity and specificity across studies.
The search yielded 69 publications on BP180 autoantibodies and 178 on Dsg3 autoantibodies. A total of 30 studies met the inclusion criteria: 17 provided data on the assays to detect autoantibodies to BP180 in a sample of 583 patients with bullous pemphigoid (BP), while 13 studies provided data on the assays to search for anti-Dsg3 autoantibodies in a sample of 1058 patients with pemphigus vulgaris (PV). The 17 studies on BP180 autoantibodies yielded a pooled sensitivity of 0.87 (95% confidence interval (CI) 0.85 to 0.89) and a pooled specificity of 0.98 (CI, 0.98 to 0.99). The area under the curve (AUC) for the SROC curve was 0.988, and the summary diagnostic odds ratio was 374.91 (CI, 249.97 to 562.30). The 13 studies on Dsg3 autoantibodies which met the inclusion criteria, yielded a pooled sensitivity of 0.97 (CI, 0.95 to 0.98), and a pooled specificity of 0.98 (CI, 0.98 to 0.99). The AUC for the SROC curve was 0.995 and the summary diagnostic odds ratio was 1466.11 (95% CI, 750.36 to 2864.61).
Results of the meta-analysis demonstrated that ELISA tests for anti-BP180 and anti-Dsg3 autoantibodies have high sensitivity and specificity for BP and PV, respectively, and can be used in daily laboratory practice for the initial diagnosis of autoimmune blistering skin diseases.
PMID: 22781589 [PubMed – as supplied by publisher] (Source: Autoimmunity Reviews)