Low sensitivity of type VII collagen enzyme-linked immunosorbent assay in epidermolysis bullosa acquisita: serration pattern analysis on skin biopsy is required for diagnosis.

Abstract

BACKGROUND:

The type VII collagen (coll VII) enzyme-linked immunosorbent assay (ELISA) has been reported to have high sensitivity (> 93%) and specificity (> 96%) for diagnosing epidermolysis bullosa acquisita (EBA) in patients who are seropositive on indirect immunofluorescence on salt-split skin (SSS).

OBJECTIVES:

To investigate the added value of the coll VII ELISA in the laboratory diagnosis of SSS-positive and SSS-negative EBA and to correlate the ELISA index with disease episode.

METHODS:

The coll VII ELISA was performed on banked sera of 28 patients with EBA: 15 SSS positive and 13 SSS negative. Sera from healthy blood donors (n = 17) and patients with other autoimmune blistering diseases (n = 29) served as controls. In four patients, the ELISA index was measured longitudinally. Serration pattern analysis by direct immunofluorescence has been prospectively performed since 2000 in 19 patients.

RESULTS:

The sensitivity in the SSS-positive group was 80% whereas it was 23% in the SSS-negative group. In the prospective EBA subset it was 45%. The sensitivity of u-serration pattern analysis on skin biopsy was 89%. Ten (53%) of these cases were seronegative with both ELISA and SSS, and would have been missed by serum analysis alone. Of the 46 control sera, one serum tested positive (specificity 97·8%). The coll VII ELISA correlated with disease activity over time in individual patients.

CONCLUSIONS:

The coll VII ELISA has limited added value in SSS-negative EBA cases. The ELISA test is valuable in differentiating EBA from antilaminin-332 mucous membrane pemphigoid and anti-p200 pemphigoid and in its ability to monitor patients with EBA serologically. U-serration pattern analysis on immunofluorescence skin biopsy is the gold standard for the diagnosis of EBA.

• Authors: J B Terra, M F Jonkman, G F H Diercks, H H Pas
• Journal: The British journal of dermatology (Br J Dermatol) Vol. 169 Issue 1 Pg. 164-7 (Jul 2013) ISSN: 1365-2133 [Electronic] England
• PMID: 23480491 (Publication Type: Evaluation Study, Journal Article)
• Copyright: © 2013 The Authors BJD © 2013 British Association of Dermatologists.

Chemical References

• Collagen Type VII

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Biopsy
• Case-Control Studies
• Collagen Type VII (metabolism)
• Enzyme-Linked Immunosorbent Assay (methods)
• Epidermolysis Bullosa Acquisita (diagnosis)
• Female
• Humans
• Male
• Middle Aged
• Prospective Studies
• Retrospective Studies
• Skin (pathology)