Pathophysiology of cystic fibrosis Flashcards
1
Q
Cystic fibrosis
A
- Inherited autosomal recessive disease
- Mutation that occours in ystic fibrosis transmembrane conductance regulator gene
- CFTR involved in the production of sweat, mucus and digestive enzymes
- Ion transportor abnormalities cause dehydrate mucous
2
Q
Long term issues of cystic fibrosis
A
- Difficulty breathing / coughing up sputum as a result of frequent lung
infections
3
Q
Other symptoms of cystic fibrosis
A
- Sinus infections,
- Poor growth
- Fatty stool
- Clubbing of the finger and toes
- Infertility in males
4
Q
Epidemiology of CF
A
- Most common mutation of delta F508 three base-pair deletion that should code for a phenylalanine
- Diagnosed during childhood mostly caucasian
5
Q
Main signs and symptoms of CF
A
- salty-tasting skin
- Poor growth and poor weight gain despite normal food intake
- Accumulation of thick, sticky mucus
- frequent chest infections, and coughing or shortness of breath
6
Q
Body systems effected by CF
A
- Lungs and sinus causing infection and inflammation
- Sweat glands elevated sweat chloride concentration
- Pancreas - Exocrine dysfunction with diabetes
7
Q
Causes of CF
A
- The CFTR gene found at q31.2 locus of chromosome 7
- Location is 7q31.2 More specifically it is found on the long arm of chromosome 7, region 3, band 1, sub-band 2
- CFTR is a type of gene known as an ABC gene - choride ion channel is the product of the gene
8
Q
Cellular processing of CFTR with cystic fibrosis
A
- Chloride ions are not transported through the chloride ion channels in CF
- Chloride ions are reduced extracellularly on surface of the epithelium
- Effecting the constituency of mucus
- Na+ and Cl- on airways surface
- Couplled to reduce water flow into aiways of the lumen dehydrates mucus less HCO3 acidifying layer
9
Q
Diagnosis of CF
A
- Limitations for using DNA testing due to CFTR mutation
- Heel prick test for newborn babies fiind common varients
- Sweat test for chlorine levels >60mM for adults
- Nasal transepithelial potential difference- increased luminal Na+ absorption makes potential more negative in CF patients
10
Q
Management of CF
A
- Polypharmacy is common
- Stratification of treatment severity
- Maintainance to improve quality of life
- Treat exacerbations aggresively
11
Q
Treatment objectives
A
- Promote clearance of secreations
- Control lung infection
- Provide accurate nutrition
- Prevent intestinal absorbtion
12
Q
CF causing lung disease
A
- Mutation of the CFTR gene
- Ion transporter abnomality
- Overly viscous mucus
- Impaired mucous clearance
- Causing an infection can be cleared by antibiotics that could cause tissue damage
13
Q
How can gene therapy in the future effect CF and lung disease
A
- Looking directly at Mutation of CFTR gene to combat risk of CF
14
Q
Why are mucolytics used?
A
- Focus on the impaired mucous clearance
15
Q
Three most common
organisms causing lung
infections in CF patients
A
- Staphylococcus aureus
- Haemophilus influenzae
- Pseudomonas
aeruginosa
