Cystic Fibrosis (CF)

The consequences of cystic fibrosis (CF) are extensive and affect almost every organ system. The clinical picture is broad and may present with acute or chronic manifestations. Gastrointestinal and respiratory symptoms make up the majority of disease manifestations; however, other signs and symptoms involving the musculoskeletal, renal, reproductive, and nervous systems are frequently involved. Additionally, the prevalence of mental health disorders is increased in patients with CF compared to that of the general population.

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Respiratory Manifestations

Upper respiratory involvement is common in CF and includes chronic rhinosinusitis and nasal polyps. Lower respiratory tract involvement leads to lung damage, which may manifest early in life and result in mucus plugging, neutrophilic inflammation, and chronic infections. Common bacterial agents include Staphylococcus aureus and Pseudomonas aeruginosa, with fungal and mycobacterial pathogens becoming increasingly prevalent. Recurrent infections and inflammation over time lead to a progressive decline in lung function, bronchiectasis, and eventual respiratory failure.  Additional manifestations that occur over the disease course include pneumothorax, hemoptysis, and infections with multidrug-resistant microorganisms. Expiratory volume in 1 second (FEV1) is a parameter obtained via spirometry that is closely monitored in patients with CF , and it drops over time as lung function decreases.1 

Gastrointestinal Manifestations 

Meconium ileus is one of the earliest manifestations of CF, and it is present in 20% of patients. Inspissated meconium in the terminal ileum leads to a mechanical intestinal obstruction that causes abdominal distension and bilious emesis.2  Meconium ileus may have a complicated disease course and result in volvulus, necrosis, atresia, or intestinal perforation.1  Another early finding is neonatal jaundice. Insufficiency of the exocrine pancreas is present in approximately 85% of patients born with CF. In some cases, patients may be born with pancreatic sufficiency that steadily progresses to insufficiency over time. Pancreatitis may also be a direct manifestation of CF, but this usually occurs in patients who are pancreas sufficient. Malabsorption, liver disease, cirrhosis, biliary calculi, small bowel bacterial overgrowth, and distal intestinal obstruction syndrome are additional gastrointestinal manifestations of CF. Distal intestinal obstruction syndrome affects 15% of all CF patients and 44% to 50% of patients with a history of meconium ileus. It should be suspected in patients with CF who develop acute-onset abdominal pain (usually periumbilical) and bilious emesis. Additional signs and symptoms include right lower quadrant pain with a palpable mass, with abdominal radiographs showing fecal loading in the right lower quadrant with air fluid levels in the dilated small bowel segments.1  

Reproductive System Manifestations

About 97% to 98% of males with CF are infertile due a congenital absence of the vas deferens.3 Female subfertility is attributed to cervical mucus abnormalities. 

Additional Manifestations

Cystic fibrosis is also associated with anxiety, depression, hearing and vestibular impairment, dyspepsia, renal failure, urinary incontinence, lymphoma, osteoporosis, CF arthropathy, musculoskeletal abnormalities, and gastrointestinal malignancy. Some manifestations, like low bone density, are multifactorial and may be due to nutritional deficiencies secondary to pancreatic insufficiency, low activity levels, and use of glucocorticoids. Cystic fibrosis arthropathy is a common manifestation in adults, presenting in 29% of patients. Prevalence rates for anxiety and depression are also significantly increased in patients with CF compared to those of the general population, and they are associated with increased age, sex (more common in women), worse health status, and adherence to treatment.1


1. Shteinberg M, Haq IJ, Polineni D, Davies JC. Cystic fibrosis. Lancet. 2021;397(10290):2195-2211. doi:10.1016/S0140-6736(20)32542-3

2. Parikh NS, Ibrahim S, Ahlawat R. Meconium ileus. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing; 2021. Accessed January 17, 2022.

3. Fertility in men with CF. Cystic Fibrosis Foundation. Accessed January 17, 2022.

Reviewed by Harshi Dhingra, MD, on 1/21/2022.