MedLecturesMadeEasy's video: Cystic fibrosis mechanism of disease

This is a mechanism of disease flowchart for cystic fibrosis, covering the etiology, pathophysiology, and manifestations. ADDITIONAL TAGS: Risk factors / SDOH Cell / tissue damage Ion channel physio Cystic fibrosis Medicine / iatrogenic Infectious / microbial Biochem / molecular bio Immunology / inflammation Signs / symptoms Tests / imaging / labs Diet / nutrition Genetics / hereditary Blockage of flow Pathophysiology Etiology Manifestations Mutation ΔF508 in CFTR gene on long arm of chromosome 7 Absence of phenylalanine (F) in position 508 of the CFTR protein Misfolded protein Defective protein is retained in the rough endoplasmic reticulum Protein degradation Absence of ATP-gated chloride channel on the cell surface of epithelial cells throughout the body Recessive disease: children of parent(s) who are heterozygous carriers (if both parents affected → 25% chance in child) Cannot reabsorb Cl- from the lumen of the sweat glands ↓ reabsorption of Na+ and H2O ↑ NaCl loss in sweat In sweat glands: Cannot transport intracellular Cl- across the cell membrane into lumen In gastrointestinal, respiratory, or urogenital tracts: ↓ secretion of Cl- and H2O → ↑ intracellular Cl- ↑ Na+ reabsorption (via ENaC) ↑ H2O reabsorption by osmosis Hyperviscous mucus and secretions accumulate and block small passages in… Salty sweat, salty baby +/- electrolyte wasting Sweat chloride testing with Cl 60 mmol/L GI tract Failure to thrive Malabsorption Meconium ileus No meconium or stool for first 1-2 days of life Abdominal distension Bilious vomiting Pancreas Weight loss Pancreatitis Steatorrhea Hypoproteinemia Fat-soluble vit deficiency (DEAK) Liver and bile duct Cholecystolithiasis → cholestasis Dark urine Jaundice Pale stools Pruritus Cholangitis → cirrhosis Portal hypertension Esophageal varices Nasal sinuses Chronic sinusitis Congestion Nasal discharge Lungs / bronchioles Recurrent pulmonary infxns → bronchiectasis Hemoptysis Chronic cough Dyspnea Wheezing Barrel chest Hypoxia → digital clubbing Urinary tract Dysuria Frequent UTIs Nephrolithiasis Flank pain Cloudy urine Hematuria Genitalia Azoospermia Absent/obstructed vas deferens Viscous cervical mucus Infertility Amenorrhea