Cystic Fibrosis

  • Etiology: 1) thick exocrine secretions – > thick mucous -> decreased mucocilliary clearance -> bacterial colonization -> bronchiectasis 2) thick exocrine secretions – > thick mucous -> mucous plugging -> ball valving -> air trapping
  • CXR: follow chronic changes, surveil for new pneumonia + pulmonary hemorrhage
  • CT: inspiratory – look for bronchiectasis – to diagnose bronchiectasis on CT need diameter of bronchus > diameter of adjacent pulmonary artery, expiratory – look for air trapping
  • Imaging: sinusitis
  • Complications: pulmonary hemorrhage from bronchial artery hypertrophy caused by infection as focal infection can erode into artery, pulmonary infection (colonized by Haemophilus influenzae, Staphylococcus aureus, Pseudomonous aeruginosa (most common)), bronchiectasis, meconium ileus, meconium peritonitis, distal intestinal obstruction syndrome / meconium ileus equivalent, malabsorption, infertility

Cases of Cystic Fibrosis

CXR of lung abscess
CXR shows a round cavitary lesion with an air-fluid level in the left upper lobe.
CT of bronchiectasis
Axial CT without contrast of the chest shows extensive bronchiectasis throughout the lungs.
CXR and angiogram of pulmonary hemorrhage in cystic fibrosis
CXR (left) shows chronic changes of cystic fibrosis. Bronchial artery angiogram (right) shows hypertrophy of the right-sided bronchial arteries.
CXR of pneumothorax
Upright CXR shows a distinct right pleural edge with no lung markings lateral to it and the right lung collapsing inferiorly and medially.
CXR of chest tube malposition with chest tube in the lung parenchyma
CXR AP (left) shows chronic interstitial fibrosis and scarring in the lungs, a left-sided chest tube, and a moderately-sized basilar left pleural air collection manifesting as a deep sulcus sign. Gross pathological specimen (right) shows the left chest tube entering the upper lobe of the left lung.
CXR of osteomyelitis of the rib
CXR PA and magnified view of the ribs (below) shows dense opacity in the right upper lobe and marked periosteal reaction of the right 4th rib posteriorly.