Investigation of intestinal permeability in pediatric patients with cystic fibrosis

Cystic fibrosis (CF) is an autosomal recessive disorder. Cystic Fibrosis Transmembrane Regulatory (CFTR) protein is a functioning as a chloride channel in the epithelial membranes of secretory cells, sinuses, lung, liver, pancreas and genital organs. CTFR is mutated in the cystic fibrosis disease. This mutation causes a structural or functional defect in the CFTR protein. CF is a progressive chronic disease that causes thickening of mucus and obstruction in the ducts. Studies shows that disruption of the intestinal barrier may be an important risk factor in the etiopathogenesis of many diseases. Serum zonulin and claudin-3 are proteins that regulate tight junctions between epithelial cells. In our study; we were included patients with CF and healthy children as a control group. Serum zonulin and claudin-3 levels were compared between the two groups. The relationship between anthropometric measurements, gender, age at diagnosis, disease severity, blood parameters, pulmonary function tests, genetic mutations, fecal elastase and sweat test results and serum zonulin and claudin-3 levels of CF patients were shown. In this study, we included 44 patients who were followed up with the diagnosis of CF in the Necmettin Erbakan University Faculty of Medicine Pediatric Pulmonary Diseases outpatient clinic and 54 healthy control groups who applied to the Necmettin Erbakan University Faculty of Medicine General Pediatrics outpatient clinic for routine control. Venous blood samples were taken from children to measure serum zonulin and claudin-3 levels in order to evaluate the intestinal permeability of the patients and control groups. The ELISA method was used for the analysis of serum samples. SPSS 18.0 program was used for statistical analysis. A p<0.05 was considered significant. A total of 98 participants were included in this study. 43.2% (n=19) of the study group were female and 56.8% (n=25) were male. In this study's cystic fibrosis patients median age was 108.50 (67.25-179.00) months, and control group's median age was 92.50 (56.75-139.75) months. There was no significant difference between the age, height, weight and body mass index (BMI) of the study and control groups. The median of claudin-3 level in the study group was statistically significantly higher than the control group (p=0.009). There was no statistically significant difference between the groups in terms of serum zonulin value (p=0.149). The median of serum zonulin level was significantly higher in women than in men among all participants included in the study (p=0.043). Serum zonulin and claudin-3 levels in pediatric patients with CF have not been studied before in the literature. We think that claudin-3 protein may be an important parameter for the role of intestinal permeability in disease etiopathogenesis in pediatric CF patients. We suggest that our findings will contribute to the literature with more comprehensive studies. Keywords: Cystic fibrosis, zonulin, claudin-3, transmembrane proteins, child.