Symptoms:

Because there are more than 1,000 mutations of the CF gene, symptoms differ from person to person. But in general they include:

• Belly pain from severe contipation
• Coughing or increased mucus in the sinuses or lungs
• Delayed growth
• Fatigue
• Infants may have salty-tasting skin
• No bowel movements in first 24 to 48 hours of life
• Stools that are pale or clay colored, foul smelling, or that float
• Recurrent respiratory infections such as pneumonia or sinusitis
• Weight loss, or failure to gain weight normally in childhood

Signs and tests:

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