Fecal elastase test vs pancreatic stimulation ???

I am the mom of a 4.5 years old child in limbo who may or may not have CF. Briefly: several negative sweat tests, 2 genetic tests that both came back with a variant that's known to be related to pancreatic problems but nothing else. And 5 fecal elastase tests over the years that came back ranging from 150 to 87 (last one recently), done at least in 2 different labs, collected by either my husband or I. Had been diagnosed as PI. And one pancreatic stimulation test recently that came back all fine, the GI doctor told us: he has no pancreatic problems, give him immodium when he has diarrheas. He has had diarrheas problems starting at 13 months old (awful smell, undigested food that floated in the toilets). He was on ZenPep for years, we stopped it except when we go to the restaurant. His stools are fairly ok most of the time but he still has loose stools here and there that he cannot control (ex: 3 in a week(BATHROOM)). He also has minor asthma issues and has had 2 sinus infections. He is doing good right now. I don't want to push CF as a diagnostics for my son, right now I am ready to forget that I ever heard about CF. But I am puzzled as why his fecal elastase tests have been bad - the GI doctor told us: it's not a reliable test. Really?
Source: Cystic Fibrosis Families Forum - Category: Respiratory Medicine Authors: Tags: Families Source Type: forums