[Celiac disease in close family members]

Risk of Celiac Disease in the First- and Second-Degree Relatives of Patients With Celiac Disease: A Systematic Review and Meta-Analysis

OBJECTIVES

First-degree relatives (FDRs) of patients with celiac disease (CD) are at high risk for CD and prevalence among them varies from 1.6 to 38%. The risk of having CD among FDRs if the FDR is sister, brother, mother, father, son, or daughter of index patient with CD is not known. We conducted a meta-analysis and calculated pooled prevalence of CD among FDRs, second-degree relatives (SDRs), and specific relations with index patient.

METHODS

On search of literature, 2,259 articles appeared of which 54 articles were included in this meta-analysis. Diagnosis of CD was based on standard criteria.

RESULTS

Pooled prevalence of CD was 7.5% (95% confidence interval (CI) 6.3%, 8.8%) in 10,252 FDRs and 2.3% (95% CI 1.3%, 3.8%) in 642 SDRs. Pooled prevalence of CD was highest in siblings (8.9%), followed by offsprings (7.9%) and parents (3.0%). Female FDRs had higher prevalence than male FDRs (8.4% vs. 5.2%, P=0.047). While sisters and daughters of index patient had the highest risk of having CD (1 in 7 and 1 in 8, respectively), the risk was 1 in 13 in sons, 1 in 16 in brothers, 1 in 32 in mothers, and 1 in 33 in fathers. There were also differences in the pooled prevalence of CD in FDRs according to their geographic location.

CONCLUSIONS

Pooled prevalence of CD among FDRs is 7.5% and varies considerably with their relationship with the index patient. The risk of CD in FDRs also varies according to gender and geographical location.

[Study of celiac disease in the pediatric population of Cantabria (Spain) and first-degree relatives]

BACKGROUND

Celiac disease (CD) is an autoimmune disease that affects genetically predisposed individuals. The HLA-DQ2 heterodimer is present in nearly 90% of patients while HLA-DQ8 is found in the remaining 10%.

AIM

To study the characteristics of CD in pediatric patients in Cantabria and their first-degree relatives, with special emphasis on factors related to haplotype, serology, and forms of clinical presentation.

PATIENTS AND METHODS

Eighty-six patients with CD and 215 first-degree relatives were HLA genotyped. Clinical, laboratory, immunologic, and histological data were obtained from all patients.

RESULTS

Clinical presentation was classical in 95% of the patients and mono-symptomatic in the remaining 5%. Anti-gliadin antibodies (AGA) and anti-transglutaminase antibodies (ATGA) were positive in 95% of the patients and negative in 5% (all with IgA deficiency). DQ2 was found in 71% of the patients (homozygotes or heterozygotes) and DQ8 was found in 9.5%. No heterodimers of risk were found in 22%. CD was found in six relatives (three were positive for AGA and four were positive for ATGA). Forty-nine percent of the relatives carried the DQ2 heterodimer and 15% the DQ8 heterodimer; no heterodimers of risk were found in 40%.

CONCLUSIONS

The most prevalent HLA found in patients with CD in the autonomous region of Cantabria was DQ2 (71%). This prevalence is clearly lower than that reported in other Spanish regions. The prevalence of CD among first-degree relatives was similar to that found in other studies performed in Spain (2.8%). Our data support the need for systematic study of the first-degree relatives of patients with CD.