10th September 2020

A 25-year-old male presents to the GP with a history of recurrent chest infections

A 25-year-old male presents to the GP with a history of recurrent chest infections, a chronic purulent cough and halitosis. He also complains that he and his partner have failed to conceive a child despite trying to do so for over 12 months. The GP suspects the patient may have a cystic fibrosis variant and orders an appropriate test for the diagnosis to be confirmed.

Which of the following is the most accurate test for a diagnosis of cystic fibrosis?

Select the SINGLE most appropriate option from the list below. Select ONE option only.