| Neonatal | Meconium ileus causing bowel obstruction (10% of cases), obstructive jaundice, bleeding disorders due to vitamin K malabsorption, salty tasting skin |
| Childhood | Fatty stools and failure to thrive (exocrine pancreas insufficiency in 85% of cases), chronic sinusitis and nasal polyps, dehydration and electrolyte disturbance, recurrent respiratory symptoms (chest infections, cough, wheeze), digital clubbing, pseudo-Bartter's syndrome, distal intestinal obstruction syndrome, rectal prolapse, acute or chronic pancreatitis |
| Adolescents, adults | CF-related diabetes mellitus, liver disease, portal hypertension, osteoporosis, arthritis, male infertility (congenial bilateral absence of the vas deferens) |