Serum Autoantibodies Detected in Celiac Disease

Serum autoantibodies specifically directed toward intracellular cytoskeletal actin filaments and known as antiactin antibodies, (AAA) were found to be associated with intestinal villous atrophy (IVA) in celiac disease.

Scientists at the University of Siena (Italy) retrospectively analyzed serum samples from 70 celiac disease (CD) patients of whom 41 were adults, with 31 females and 10 males, with an age range of 16-76 years; and 29 children of whom 18 were females and 11 males, whose ages ranged from 2-14 years. The study included 24 healthy controls that were also analyzed retrospectively for the presence of AAA. All celiac patients had to have antitransglutaminase (a-tTG), antiendomysial antibodies (EMA) positivity, and abnormal intestinal histology as requirements for inclusion in the study.

The investigators used a commercial indirect immunofluorescence (Eurospital; Trieste, Italy) test to detect the presence of immunoglobulin A (IgA)-AAA. The indirect immunofluorescence test used had a specificity of 100%; but the sensitivity of the test was not high at only 25.7%. There was significant association between the serum AAA which was more frequently positive in CD patients with total IVA (77.8%).

The authors concluded that IgA-AAA cannot take the place of much more sensitive tests such as a-tTG and EMA in the diagnosis of CD because of their low sensitivity. Nonetheless, these antibodies could be determined in a-tTG and/or EMA positive patients who cannot undergo an intestinal biopsy because of a severe contraindication, or in the case of negative consensus regarding endoscopy, or when the histology interpretation is difficult.

The indirect immunofluorescence commercial test with intestinal epithelial cells as substrate offers a useful method for IgA-AAA determination. Serum IgA-AAA positivity is indicative of more severe intestinal histology damage and their assay could be a real help to the clinician, especially in the complicated cases. The study was published on January 4, 2013, in the Journal of Clinical Laboratory Analysis.

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University of Siena
Eurospital