CF is a chronic progressive disease that can present with protein and fat malabsorption (failure to thrive, hypoalbuminemia, steatorrhea), liver disease (cholestatic jaundice), or chronic respiratory infection (Table 137-1). Many infants currently are diagnosed based on newborn screening, which has been available in all 50 states and the District of Columbia since 2010. Older children commonly present with pulmonary manifestations such as poorly controlled asthma and chronic respiratory infections. The respiratory epithelium of patients with CF exhibits marked impermeability to chloride and an excessive reabsorption of sodium. This leads to a relative dehydration of airway secretions, which results in airway obstruction and impaired mucociliary transport. This, in turn, leads to endobronchial colonization with bacteria, especially Staphylococcus aureus and Pseudomonas aeruginosa. Chronic bronchial infection results in persistent or recurrent cough that is often productive of sputum, especially in older children. Chronic airway infection leads to airway obstruction and bronchiectasis and, eventually, to pulmonary insufficiency and premature death. The median age of survival (years) is currently in the mid-30s. Digital clubbing is common in patients with CF, even in those without significant lung disease. Chronic sinusitis and nasal polyposis are common.
Pulmonary infections with virulent strains of Burkholderia cepacia are difficult to treat and may be associated with accelerated clinical deterioration. Allergic bronchopulmonary aspergillosis (ABPA) is a hypersensitivity reaction to Aspergillus in the CF airways. It causes airway inflammation/obstruction and aggravates CF lung disease. The treatment for ABPA is systemic corticosteroids (prednisone) and anti-fungal agents (itraconazole). Minor hemoptysis is usually due to airway infection, but major hemoptysis is often caused by bleeding from bronchial artery collateral vessels in damaged/chronically infected portions of the lung. Pneumothoraces can occur in patients with advanced lung disease.
Bronchiectasis, bronchitis, bronchiolitis, pneumonia Atelectasis Hemoptysis Pneumothorax Nasal polyps Sinusitis Airway reactivity Cor pulmonale (associated with chronic hypoxemia) Respiratory failure Mucoid impaction of the bronchi Allergic bronchopulmonary aspergillosis
Meconium ileus (infants) Meconium peritonitis (infants) Volvulus (infants) Intestinal atresia (infants) Distal intestinal obstruction syndrome (non-neonatal obstruction) Rectal prolapse Intussusception Fibrosing colonopathy (strictures) Appendicitis Pancreatitis Hepatic cirrhosis (portal hypertension: esophageal varices, hypersplenism) Neonatal obstructive jaundice Hepatic steatosis Gastroesophageal reflux Cholelithiasis Growth failure (malabsorption) Fat soluble vitamin deficiency states (vitamins A, K, E, D) Insulin deficiency, symptomatic hyperglycemia, diabetes Malignancy (rare)
Infertility Delayed puberty Edema-hypoproteinemia (due to protein malabsorption) Dehydration–heat exhaustion Electrolyte disturbances (hyponatremia, hypokalemia, hypochloremia, and metabolic alkalosis) Hypertrophic osteoarthropathy–arthritis Digital clubbing