Cystic fibrosis. Problems encountered with sweat testing
B. J. Rosenstein, T. S. Langbaum, E. Gordes and S. W. Brusilow
The sweat test is the only practical and reliable laboratory test for
confirmation of the diagnosis of cystic fibrosis. Among 234 patients
referred to The Johns Hopkins Hospital for sweat testing, 62 had had a
previous test; 29 tests had been reported as negative, and 33 tests had
been reported as positive. Results of quantitative
pilocarpine-iontophoresis sweat tests at this center led to a change in
diagnosis in 27 (43.5%) of these 62 patients. Most of the errors were
false-positive.
