Follow-up on question_sweat test

Question

In following up on my last question (33 week-old preterm baby) I would like to let you know that the first IRT value at birth was 30 with 117 maximum value and 13 days later 52 with 90 to be the limit. We do have an older child at home (3 years old), but it does not attend a kindergarten, but he had a cold at some point recently. The pediatrician thinks that CF in very unlikely, but because the illness was rather long she would like us to do the sweat test. The baby’s stool in normal and its sweat is not salty. I would like to stress that now when the weather is good, the baby is well and only has a permanent nose congestion. It has gained 500 gr in 28 days, something that has pleased the pediatrician. We are upset about the idea of the test.

Answer

Dear friend,
Lately your child has a nose congestion and has gained weight. Based on what you describe the possibility of CF is not likely. Your pediatrician thinks the same, but wants the child to have a sweat test.
Most sweat tests that are performed in children are negative, and only a very small percentage (1-5%) is positive. The reason they are performed is to exclude the possibility of CF. Therefore, the idea of doing a sweat test should not upset you.

Yours friendly,
Dr. Stavros Doudounakis

03.11.2014