Cystic Fibrosis (CF) is a disease that affects salt and water transport in multiple organs. Many CF patients suffer from abdominal pain and this could be due to intestinal inflammation. However, so far we do not know how many of the CF patients actually do have intestinal inflammation when looking at intestinal specimens. There is a proven connection between chronic inflammation and developing colorectal cancer and over the years more CF patients are developing colorectal cancer. Thus, it becomes increasingly important to look for the presence of intestinal inflammation in CF patients since early treatment may improve their symptoms and reduce the risk for colorectal cancer.

The aim is to determine the prevalence of intestinal inflammation by measurement of fecal calprotectin and/or histological evaluation of intestinal tissue biopsies in both pediatric and adult CF populations.

Pediatric CF population (Age 10-18 years):

1. Determine the prevalence of intestinal inflammation in a cohort of pediatric CF patients based on fecal calprotectin levels in stool samples.
2. Assess the correlation between fecal calprotectin and abdominal symptoms/QOL.

Adult CF population (Age ≥ 18 years):

1. Determine the prevalence of intestinal inflammation in a cohort of adult CF patients based on histological evaluation of intestinal tissues biopsies and fecal calprotectin levels in stool samples

   1. in adult CF patients who have not undergone lung or liver transplantation.
   2. in adult CF patients who have undergone lung or liver transplantation.

2. Assess the correlation between fecal calprotectin and histological-proven intestinal inflammation in adult CF patients.

3. Assess the correlation between histological-proven intestinal inflammation and abdominal symptoms/QOL as well as the correlation between fecal calprotectin and abdominal symptoms/QOL.

INCLUSION CRITERIA ;

Pediatric cohort:

1. Diagnosis of CF
2. Informed consent obtained
3. Age 10-18 years

Adult cohort:

1. Diagnosis of CF
2. Informed consent obtained
3. Age ≥ 18 years
4. Patient undergoing a colonoscopy for a clinical indication

EXCLUSION CRITERIA ;

Pediatric Cohort:

1. Patients with the diagnosis of IBD.
2. Patients during an episode of acute gastroenteritis or a pulmonary exacerbation.

Adult cohort:

1. Patients with the diagnosis of IBD.
2. Any health condition, e.g. coagulopathy, sepsis, severe bacterial colitis that would increase the risk for perforation or bleeding when taking intestinal tissue biopsies.

Pediatric and adult population diagnosed of cystic fibrosis will be included in this study.