PTGS1 and exocrine pancreatic insufficiency: Our study resulted in several main findings: (a) there is a limited relationship between the severity of CFTR genetic dysfunction and PG production; (b) exocrine pancreatic insufficiency is closely associated with the severity of CFTR dysfunction and PG production; (c) there is no correlation between PG levels and lung function parameters; (d) PG production associates with both clinical status and radiological findings (bronchiectasis and air trapping); and (e) COX-1 and COX-2 gene polymorphisms do not appear to contribute to the regulation of PG synthesis.