Lecture 11 - Bronchiectasis and CF Flashcards
Bronchiectasis
Chronic irreversible dilation of one or more bronchi
Features of bronchiectasis
- Dilated bronchi
- Poor mucus clearance
- Predisposition to recurrent bacterial infection
Causes of bronchiectasis
Chronic inflammation :
Post infection:
- TB
- whooping cough
Mucocilliary clearance defect:
- CF
- Primary ciliary dyskinesia
- Young’s syndrome
- Kartagener syndrome
Idiopathic
Alpha 1 antitrypsin deficiency
Rheumatoid arthritis
HIV
Obstruction:
- Foreign body
- Tumour
- lymph node
Toxic insult:
- Gastric aspiration
Aetiology of bronchiectasis
- Chronic inflammation
- Destruction of elastic and muscular components of bronchus walls
- Peribronchial fibrosis
CT scan
Signet ring sign - bronchus more dilated than pulmonary artery branch
Symptoms of bronchiectasis
Chronic cough
Daily sputum production
Fever
SOB on exertion
Intermittent haemoptysis
Chest pain
Fatigue
Less common: wheeze
Signs of bronchiectasis
Hypoxaemia - advanced Recurrent fever Haemoptysis Weight loss Fine crackles Rhonchi
Clubbing - less common
Breath sounds
Fine crackles
High pitched inspiratory squeaks
Rhonchi - turbulent flow- low pitched gurgling
Young’s syndrome
Bronchiectasis
Sinusistis
Reduced fertility
Kartagener syndrome
Bronchiectasis
Sinusitis
Sinus invertus
Common organisms that cause bronchiectasis
Haemophilus influenzae Psuedomonas aeruginosa Streptococcus pnuemoniae Mycobacteria tuberculosis Nontuberculosis mycobacteria
Fungus - aspergillus and candida
Vicious cycle
- Bronchial dilation
- Leads to mucous accumulation and impaired ciliary function
- Increased risk of infection due to impaired ciliary function and mucous stasis
- Infection leads to inflammation and loss of elastic fibres and smooth muscle in the the bronchus
- Leads to more dilation
Alpha 1 antitrypsin deficiency
- Deficiency in alpha 1 antitrpsin
- Less inhibition of neutrophil elastase
- Increase in neutrophil elastase breaks down elastase in alveoli
- Less recoil and dilated
Sputum test
May see:
psuedomonas aeruginosa
Haemophilus influenzae
Atypical mycobacteria
Spirometry
Obstructive:
- Reduced FEV1
- FEV1/FVC less than 70%
Summary of bronchiectasis
Location: Bronchus
Pathology: Bronchus dilation and mucus accumulation with scarring
Aetiology: Persistant or severe infection
Symptoms: Chronic cough, sputum and fever
Bronchiectasis management
Physio and airway clearance
Sputum sampling
Vaccinations against haemophilus influezae and streptococcus pnuemoniae
Exacerbation
Deterioration of 3 or more symptoms for at least 48 hours
Cystic fibrosis
Autosomal recessive
Mutation of the gene for the cystic fibrosis transmembrance conductance regulator CFTR
- Cl- transported into lumen
Cystic fibrosis causes
Thickened, sticky mucous accumulation
Malabsorption in pancreas
Biliary cirrhosis - affects liver
Infertility due to vas deferens defect
CF diagnosis
- History of CF in a sibling
- +ve screening test in newborn
Sweat test - increased sweat chloride concentration
Identification of 2 CF mutations - extended genotyping
Presentation of CF in newborns
Meconium ileus
Intestinal malabsorption - lack of pancreatic enzymes
Newborn screening
Recurrent chest infection
Type 3 diabetes - destruction of pancreatic beta islets of Langerhan cells - reduction of insulin
Late diagnosis
Atypical CF
Some variants of CF may present later and misdiagnosed e.g.
idiopathic pancreatitis
recurrent lung infections
CF lifestyle advice
Avoid other CF patients No smoking Avoid people with chest infections Avoid jacuzzis - psuedomonas Vaccinations NaCl tablets in hot weather and vigorous exercise
Avoid other CF patients
As immunocompromised and have more bacteria in lungs that can infect CF patients
Management of CF
Physio and airway clearance
CF specialist centre
Vaccinations
Optimal nutritional state
Classes of CF
I - no protein production
II - Protein made but doesn’t get to cell membrane
III - Protein made but doesn’t work
IV - Protein made but partially active (common in adults)
V - Protein expressed but reduced quantity
VI - Protein gets to membrne but unstable
Lumacaftor
CFTR chaperone
Ivacaftor
CFTR potentiator - improves Cl- transport through the channel as increases probability channel is open
Mutation of CF
Phe508del
Deletion of phenylalanine at position 508of the polypeptide chain
Chromosome 7