17 Cystic Fibrosis - Boards and Beyond

  • name from fibrous cyst found in pancreas

  • abnormal: sticky mucosal surfaces because not enough water

  • abnormal folding: protein targeted for ubiquitin protease. Result: no protein on cell surface
  • protein is made just didn't make it to the membrane

Symptoms

  • testing for recurrent infections leads to CF diagnosis
  • meconium: bowel obstructions

  • no bowel movement in first few days
  • air fluid: when bowel obstructed, fluid backs up in obstruction, mix up with air = air fluid levels

  • no pancreatic enzymes to absorb fat

  • stable for a while then develop acute exacerbation
  • pseudomonas both for acute and chronic exacerbation

  • clog up pancreatic duct
  • recurrent pancreatitis: burn out islet cells

  • vitamin E: antioxidant. Deficient leads to anemia, acanthocytosis, muscle weakness, spinocerebellar tract demylelination (ataxia). Neurologic symptoms without megaloblastic anemia

  • thickened mucous can develop into polyps inside nose

Diagnosis

  • iontophoresis: electric field for test
  • pilocarpine: muscarinic, parasympathetic, induce sweating (sweat induced by sympathetic but Ach NT)

  • nasal potential difference: Na abnormality, not Cl abnormality

Treatment

  • dying neutrophils spill DNA, polymerized in mucous
  • saline: moisten secretions
  • N-acetylcysteine: cleaves disulfide bonds in mucous, but causes bronchospasm
  • transplant: have to be relatively healthy (kids)

  • not always done
  • trypsinogen: pancreatic zymogen
  • heel stick testing