Clinical Features

Gastrointestinal symptoms are common in children. The presence of these features during infancy should raise suspicion for CF.

• Meconium ileus (in newborns)

• Failure to thrive (due to malabsorption)

• Pancreatic disease

  • Pancreatitis

  • Exocrine pancreatic insufficiency

    • Foul-smelling steatorrhea (fatty stools) may occur.

    • Malabsorption

    • Abdominal distention

    • Diarrhea

    • Hypoproteinemia

    • Deficiency of fat-soluble vitamins

• CF-related diabetes mellitus (CFRD)

• Liver and bile duct abnormalities

  • Cholecystolithiasis, cholestasis

  • Fatty metamorphosis of the liver, eventually progressing to liver cirrhosis

  • Biliary cirrhosis with portal hypertension, jaundice, and/or esophageal varices

• Intestinal obstruction: abdominal distention, pain, and a palpable mass

• Rectal prolapse (rare)

In almost all cases of meconium ileus, cystic fibrosis is the underlying disease.

Respiratory symptoms are common in adulthood. CF should be considered in individuals with the following features:

• Chronic obstructive lung disease with bronchiectasis

• Chronic sinusitis: nasal polyps may eventually develop

• Recurrent or chronic productive cough and pulmonary infections

  • S. aureus is the most common cause of recurrent pulmonary infection in infancy and childhood.

  • P. aeruginosa is the most common cause of recurrent pulmonary infections in adulthood.

  • Other commonly involved bacteria

    • Burkholderia cepacia: can lead to cepacia syndrome, a severe necrotizing pneumonia that is often accompanied by rapid respiratory decline and can progress to sepsis [13]

    • S. pneumoniae

    • H. influenzae

  • Increased susceptibility of individuals with CF to opportunistic, potentially life-threatening pathogens (e.g., Pseudomonas aeruginosa, Aspergillus)

    • Infections with Pseudomonas aeruginosa → rapid decline in pulmonary function (patients with CF go through multiple antibiotic courses in their lifetime → increasing resistance of Pseudomonas aeruginosa to commonly used antibiotics) [14]

    • A chronic infection with Aspergillus species may lead to allergic bronchopulmonary aspergillosis (see “Complications” below)

• Pulmonary obstruction and airway hyperreactivity may manifest with expiratory wheezing and/or dyspnea.

• Barrel chest , moist rales (indicate pneumonia), hyperresonance to percussion

• Hemoptysis

• Signs of chronic respiratory insufficiency: digital clubbing associated with chronic hypoxia

• Particularly salty sweat

• Possible electrolyte wasting

• Frequent fractures due to osteopenia

• Kyphoscoliosis

• Urinary

  • Nephrolithiasis, nephrocalcinosis

  • Frequent urinary tract infections

• Genital

  • Men: usually infertile

    • Obstructive azoospermia is common, spermatogenesis may be intact

    • The vas deferens may be absent.

    • Undescended testicle

  • Women: reduced fertility

    • Viscous cervical mucus can obstruct fertilization.

    • Menstrual abnormalities (e.g., amenorrhea)

  • Delayed development of secondary sexual characteristics