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Objectives Emerging data suggest higher celiac disease(CD) prevalence in SLE, indicating the existence of shared genetic risk factors between the two disorders. The human leukocyte antigen (HLA)-DQ2 and DQ8 genotypes are strongly linked to CD, present in almost all CD patients. We aimed to investigate the distribution of HLA-DQ2 and HLA-DQ8 in SLE patients and in healthy individuals in central Greece.Methods We conducted a 1:1 gender and ethnic background paired case-control study. SLE patients fulfilled the EULAR/ACR Criteria for SLE and were recruited from our department. Genomic DNA was extracted from peripheral blood samples and HLA DQ2 and DQ8 alleles were detected using multiplex PCR with a commercially available kit targeting HLA-DQQA1 and HLA-DQB1 loci. HLA status was classified as DQ2+, DQ8+, DQ2+DQ8+ or negative and the primary exposure was DQ-positivity, defined as presence of DQ2 and/or DQ8. For the paired comparison of DQ-positivity between cases and controls the McNemar’s test was utilized (two-sided alpha=0.05). A matched odds ratio (OR) was calculated from discordant pairs with a 95% confidence interval(CI).Results One hundred participants were included, comprised of 50 SLE cases and 50 controls (88% females in both groups). DQ2 and/or DQ8 positivity was present in 34%(17/50) of SLE cases versus 26%(13/50) of controls. Specifically, DQ2 sole positivity was detected in 32% of SLE cases and 22% of controls, while DQ8 sole positivity was uncommon, observed in 2% in both groups. The combined DQ2/DQ8 genotype occurred only in one participant from the control group. In the matched-pair analysis of DQ positivity, McNemar’s test showed no significant difference between groups (p=0.56). The matched OR was 1.36(95% CI 0.59-3.28). When DQ2 sole positivity was examined, SLE patients did not differ from controls (p=0.4), while the matched OR was 1.56(95% CI 0.63-4.1).Abstract LBA:01:41 Figure 1Conclusions This case-control study identifies higher HLA-DQ2 positivity in SLE patients compared to a matched control group population in Central Greece. However, this difference was not significant. Given the relatively small sample size, the observed increase (32% vs 22%) warrants larger-scale studies to determine whether SLE presents increased genetic predisposition for developing CD in this geographical region.