My son has chronic lung problems and constipation should he be tested for cystic fibrouses?

Yes. Cystic fibrosis can present with a myriad of symptoms. You do not have to be of northern european descent to be at risk. A simple sweat chloride test can be done if your child is over two months old and able to sweat. Of course other conditions may be to blame. Reflux can cause chronic respiratory symptoms and affect dietary intake that may result in constipation or complicate it.