Sir.—I read with interest the article "Cystic Fibrosis Mistaken for Gastroesophageal Reflux With Aspiration" by Frates and Cox (Journal 1981;135:719-720).
I do have some problems accepting the authors' recommendation that "a sweat test be performed on all infants with possible GER [gastroesophageal reflux]." Considering the large number of cases presented, it would seem that this approach would not be cost-effective. A second consideration is the usefulness of the early diagnosis of cystic fibrosis (CF). Does the early treatment make much difference? From the cases reported in the article, it seems that the delay of diagnosis did not affect the outcome.
I fear that we often do too much testing with minimal results. Clinical judgments seem to be taking a second place to laboratory tests. I realize that laboratory tests are important, but blanket recommendations for tests with small return for a common problem are dangerous. Besides the cost, many