My son has had repeated sweat test done, two postive, two negative so far, his blood work came back as showing no cf gene shown but they are still undecided and dont wanna rule this out yet, he is 4 and only 26 pounds, he does have trouble digesting food so he is taking enzymes for this. The doctors want say but is not there any other testing that can determine if he really has this cf because l am afraid the enzymes will do more harm then good if he really does not have this.....

If there is NO CF gene he DOES NOT have it! The sweat chloride test is not the most definitive test. Are u & his father carriers of CF? Either way if the gene is not in him, he does not jave it. And from knowledge & experience an enzyme deficiency is better than CF. My son has similar problems & tested neg for CF, but could not digest some foods. They put him on enzyme therapy, this was all when he was 1-2. He had to have special formula & now he is 7, still small for his age but no medication needed. We avoid foods that cause him problems, which there r not many. l was in college for Respiratory while going through all this & did not know half what l know now so l was terrified then. He had severe asthma on top of it all which made me question the CF thing more, because l am a carrier. If u need more advice feel free to email me.