IgA antibodies against deamidated gliadin peptides in patients with chronic liver diseases.
OBJECTIVE
IgA antibodies against tissue-transglutaminase (anti-tTG-IgA) and IgA and IgG antibodies against deamidated gliadin peptides (anti-DGP-IgA and anti-DGP-IgG) are considered specific for celiac disease (CD) whereas, patients with chronic liver disorders have an increased risk of latent CD development. We investigated the prevalence and clinical significance of anti-DGP-IgA, anti-DGP-IgG and anti-tTG-IgA in a large cohort of patients with chronic liver diseases.


METHODS
668 patients without gastrointestinal symptoms (426 viral hepatitis, 94 autoimmune liver diseases, 61 alcoholic disease, 46 non-alcoholic fatty liver disease, 41 with other liver disorders) were investigated by ELISAs (INOVA Diagnostics). Patients positive for at least one autoantibody invited for a small-intestinal biopsy and HLA-DQ typing.


RESULTS
Anti-DGP-IgA were detected in 8.5%, anti-DGP-IgG in only one (0.15%, P<0.001) and anti-tTG-IgA in 5.8% of patients (P=0.05). Fifty-two were anti-DGP-IgA(+)/anti-tTG-IgA(-), 34 anti-DGP-IgA(-)/anti-tTG-IgA(+), and 5 anti-DGP-IgA(+)/anti-tTG-IgA(+). Anti-DGP-IgA positivity was associated with older age (P<0.05), cirrhosis (P<0.05) and increased IgA (P<0.05) whereas, anti-tTG-IgA only with cirrhosis (P<0.05). Histology and HLA-typing compatible with CD was revealed in 4/14 anti-DGP-IgA(+)/anti-tTG-IgA(-), 0/13 anti-DGP-IgA(-)/anti-tTG-IgA(+) and 2/2 anti-DGP-IgA(+)/anti-tTG-IgA(+). All 6 patients diagnosed with CD were anti-DGP-IgA(+) and only 2 anti-tTG-IgA(+).


CONCLUSIONS
Although a significant number of patients had detectable CD-related autoantibodies, anti-DGP-IgA test seems better than anti-tTG-IgA for unmasking occult forms of CD in patients with chronic liver disorders. The known good performance for CD diagnosis of anti-DGP-IgG test was not confirmed in this specific group of patients.
Department of Medicine and Research Laboratory of Internal Medicine, Medical School, University of Thessaly, Larissa, Greece.
Nikolaos K
NK
Gatselis
Kalliopi
K
Zachou
Gary L
GL
Norman
George
G
Tzellas
Matthaios
M
Speletas
Stella
S
Gabeta
Anastasios
A
Germenis
George K
GK
Koukoulis
George N
GN
Dalekos
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology; D015415:Biomarkers / Q000097:blood; D002446:Celiac Disease / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000276:immunology; D002648:Child; D002908:Chronic Disease; D005260:Female; D005903:Gliadin / Q000097:blood* / Q000276:immunology; D006650:Histocompatibility Testing; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood* / Q000276:immunology; D008107:Liver Diseases / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011503:Transglutaminases / Q000097:blood* / Q000276:immunology
D001323:Autoantibodies; D015415:Biomarkers; D007070:Immunoglobulin A; D005903:Gliadin; D011503:Transglutaminases