Increased Prevalence of Celiac Disease in Patients with Cystic Fibrosis: A Systematic Review and Meta-Analysis

Objectives: Immune regulation seems to be altered in cystic fibrosis (CF), thus potentially predisposing patients to developing autoimmune diseases (AID). In this meta-analysis, we aimed to evaluate the prevalence of celiac disease (CeD) among CF patients as by far the most commonly reported autoimmune disease in this population and, secondly, to review the observations on other, less frequently studied autoimmune diseases. Methods: We conducted a systematic literature search for studies that discussed AIDs among CF patients. Following standard selection and data collection, we calculated pooled raw prevalence with 95% confidence intervals (CI) for biopsy-verified CeD and seropositivity. Results: Out of the 21 eligible studies, 15 reported on CeD. Pooled prevalence of biopsy-verified CeD was 1.8% (CI 1.1–2.7%) according to a homogeneous dataset from six prospective, consecutive screening studies, while it proved to be 2.3% (CI 1.1–4.7%) according to a heterogeneous dataset from the other studies. Tissue transglutaminase IgA positivity was detected in 4.5% of CF cases (CI 2.8–6.9%), while tissue transglutaminase IgA–endomysial antibody IgA double positivity was found in 2.4% of them (CI 1.5–3.9%). Findings on other AIDs were strongly limited. Conclusions: The pooled prevalence of CeD in CF seemed to be more than twice as high compared to the global prevalence; therefore, routine screening of CeD could be considered in CF.