Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:
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- Defect of the cystic fibrosis transmembrane conductance regulator (CFTR)
- CFTR functions as an ATP-regulated chloride channel that regulates the activity of chloride and sodium channels on the cell surface:
- Abnormal electrolyte transport in exocrine glands and secretory epithelia
- Decreased exocrine pancreatic function with malabsorption
- Thickened mucus, recurrent pulmonary infections, and progressive obstructive damage to the lungs
- Recurrent sinus disease
- Occurs in 1:3,600 live births in White population, 1:29,000 in African American population; 1:6,500 in Hispanic population
- 30% of cases diagnosed by newborn screening
- 75% cases diagnosed in the 1st 2 yr of life
- ∼30,000 children and young adults in US have CF.
- Median life expectancy in US about 40 yr.
- 40% of CF patients are older than 18 yr.
- 10 million Americans are unknown, asymptomatic carriers of the defective gene.
- 16% of lung transplants in US due to CF
Recessively inherited genetic disease, involving the CFTR gene on the long arm of chromosome 7:
- Different mutations; variable phenotypes.
- Classic disease: Homozygous DF508 mutation.
- Most common lethal genetic disease in US
EtiologyCommon organisms in patients with pneumonia; often multiple drug resistance:
- Staphylococcus aureus:
- Pseudomonas aeruginosa:
- Prevalence increases with age; >70% of adults are chronically infected.
- Haemophilus influenzae
- Stenotrophomonas maltophilia
- Burkholderia cepacia:
- Prevalence 3%
- Associated with rapid clinical deterioration
- Achromobacter xylosoxidans
- Mycobacteria (nontuberculous):
- Mycobacterium avium complex, Mycobacterium abscessus