Prediction by Ultrasound of the Risk of Hepatic Cirrhosis in Cystic Fibrosis

For subjects in longitudinal follow up, this study will: 1. Collect detailed clinical and demographic information about each subject at enrollment and during follow up, 2. Obtain and store imaging data from the subject at entry and during follow up, 3. Obtain and store serum, plasma and urine samples from the subject at entry (after matching) and during follow up, 4. Obtain and store DNA from the subject, 5. Obtain and store DNA from the biological parents, 6. Obtain and store quality of life data from the subject and parents at enrollment and during follow up