Early diagnosis and prompt treatment of cystic fibrosis is important to avoid unnecessary testing, provide appropriate treatments and counselling, and ensure access to specialised medical services. CF should be tested for at birth if there are other children with CF in the family, if screening tests are abnormal or if a baby is born with a bowel blockage 1 . Some children initially present with wheeze only, which may be attributed to asthma. The standard diagnostic test for cystic fibrosis is the sweat test. In this test, pilocarpine, a drug that stimulates secretion from sweat glands, is introduced through the skin with a small electric current.
Sweat is absorbed onto filter paper and is then analysed for chloride content.
If possible, the sweat test should be performed at a certified centre because the test can be hard to perform correctly and results may be difficult to interpret. The test is performed twice to be sure that the results are accurate 3 . The diagnosis of CF should be based on one or more of the above features, a history of CF in a sibling, or a positive neonatal screening test, plus laboratory evidence of the CF gene. Cystic Fibrosis and School. A guide for Teachers and Parents.