Diagnostic significance of HLA-DQ typing in patients with previous coeliac disease diagnosis based on histology alone.
BACKGROUND
Coeliac disease is strongly associated with human leukocyte antigen (HLA)-DQ2 or DQ8 genotypes. The diagnosis is based on demonstrating crypt-hyperplastic villous atrophy, endomysial or transglutaminase antibodies and correlation of disease activity with gluten intake.


OBJECTIVE
To evaluate the clinical utility of HLA-DQ typing, when coeliac disease diagnosis had previously been established solely by histology.


METHODS
HLA-DQ alleles, endomysial and transglutaminase antibodies were investigated and histology slides reviewed in 70 patients diagnosed 2-25 years earlier by small-intestinal biopsy but without measuring endomysial or transglutaminase antibodies. Patients without DQ2 or DQ8 or without unequivocal villous atrophy were followed-up on free diet by using serology and biopsies.


RESULTS
All 40 endomysial/transglutaminase antibodies positive patients carried DQ2 or DQ8, and 39 of them had severe villous atrophy. Only 56% of patients without endomysial or transglutaminase antibodies positivity had DQ2 or DQ8 (P < 0.001). Seropositivity and relapse developed in 4 of 11 DQ2 positive but in none of 15 DQ2 and DQ8 negative patients on long-term gluten exposure.


CONCLUSIONS
Coeliac disease diagnosis based solely on histology is not always reliable. HLA-DQ typing is important in identifying DQ2 and DQ8 negative subjects who need revision of their diagnosis, but it does not have additive diagnostic value if endomysial positivity is already known.
Kapitány
A
A
Research Group of Autoimmune Diseases, Hungarian Academy of Sciences, Debrecen, Hungary.
Tóth
L
L
Tumpek
J
J
Csípo
I
I
Sipos
E
E
Woolley
N
N
Partanen
J
J
Szegedi
G
G
Oláh
E
E
Sipka
S
S
Korponay-Szabó
I R
IR
D000293:Adolescent; D000328:Adult; D002446:Celiac Disease / Q000097:blood / Q000175:diagnosis* / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D020022:Genetic Predisposition to Disease; D006683:HLA-DQ Antigens / Q000097:blood / Q000235:genetics*; D006650:Histocompatibility Testing; D006801:Humans
D006683:HLA-DQ Antigens