Exocrine Pancreatic Insufficiency's Prevalence in Active Crohn's Disease

"We will collect 24 hours stool to search for steatorrhea, and to measure elastase and calprotectin.~We will collect a total of 8 additional blood tubes (25mL), during regular blood sampling for a patient under biological therapy for a Crohn's disease.~We will gather the total caloric and fat intake with a diet record."