A blood test is available to help detect CF. The test looks for variations in a gene known to cause the disease. Other tests use to diagnose CF include:
- Immunoreactive trypsinogen (IRT) test is a standard newborn screening test for CF. A high level of IRT suggests possible CF and requires further testing.
- Sweat chloride test is the standard diagnostic test for CF. A high salt level in the patient's sweat is a sign of the disease.
Other tests that identify problems that can be related to cystic fibrosis include:
- Chest x-ray or CT scan
- Fecal fat test
- Lung function tests
- Measurement of pancreatic function
- Trypsin and chymotrypsin in stool
- Secretin stimulation test
- Upper GI and small bowel series