Bronchiectasis And Cystic Fibrosis Flashcards
Define bronchiectasis
Chronic irreversible dilation of one or more bronchi - pathological condition or idiopathic
What is the pathology of problems associated with bronchiectasis?
enlarged bronchi -> poor mucus clearance and impaired ciliary function -> Increased risk of infection -> chronic inflammation -> destruction of elastic and muscular components of bronchial wall and peribronchial fibrosis
What would a CXR of bronchiectasis tell you?
Usually abnormal but inadequate in diagnosis of quantification of bronchiectasis/ bronchial dilation
How do you diagnose Bronchiectasis?
Gold standard diagnostic investigation = high resolution CT
Should see bronchial dilation bigger than adjacent blood vessel and bronchial wall thickening
What is a signet ring sign?
a Healthy lung bronchus is slightly smaller than the pulmonary artery whereas
In bronchiectasis (SRS) the bronchus is markedly dilated compared to the artery/ arteriole
What are the clinical symptoms of bronchiectasis?
Very common:
Chronic cough, daily sputum production (varies quantity/colour)
Common (50%): Intermittent haemoptysis Breathlessness on exertion Recurrent fever Nasal symptoms Chest pain Fatigue
Less common:
Wheeze
What are the clinical signs of bronchiectasis?
Pulse oximetry May reveal hypoxaemia in advanced cases
Fever
Haempytosis
Fine crackles (rales) (collapsed airways forced open)
High-pitched inspiratory squeaks
Rhonchi (low pitched breathing sounds)
Crackles & wheezing lung sounds from CF with bronchiectasis
Weight loss
Clubbing of digits 5%
What are some causes of bronchiectasis?
Post infective - whooping cough (pertussis), TB (less western countries)
Immune deficiency (hypogammaglobulinaemia)
Mucocilliary clearance defects (CF, primary ciliary dyskinesia, Young’s syndrome (triad bronchiectasis, sinusitis, reduced fertility), kartagener syndrome (triad of bronchiectasis, sinusitis, situs inversus)
Idiopathic
Alpha-a-antitrypsin deficiency
Obstruction
toxic insult
Allergic bronchopulomary aspergillosis
Secondary immune deficiency
Rheumatoid arthritis
Association- IBD
What are some common organisms bronchiectasis patients can suffer with?
Haemophilia influenzae
Moraxella catarrhalis
(In COPD too)
Pseudomonas aeruginosa
Streptococcus pneumoniae
Fungi- aspergillus, candida
Mycobacterium tuberculosis
What are some pulmonary function tests used to measure progress of bronchiectasis?
Initial and follow up spirometry
- reduced forced expiratory volume (FEV1) or an FEV1/ forced vital capacity ratio of <70%
- elevation of RV/ TLC ratio consistent with air trapping
-diffusing capacity for carbon monoxide may be reduced severe
Not part of gas exchange system so diffusing capacity isn’t reduced in early disease
Describe some differences between chronic bronchitis and bronchiectasis?
CB: bronchus, mucous gland hyperplasia, hypersecretion, brought on by smoking/ pollutants, cough, sputum production
B: bronchus, airway dilation, scarring, brought on by persistent or severe infections, cough, Purulent sputum, fever
How do you manage bronchiectasis?
Physio/ airway clearance - daily clearance
Sputum stapling
Exclude immunodeficiency
Annual flu and routine vaccinations against haemophilus influenza and streptococcus pneumonia
MDT is key
Management plan for exacerbations
How do we define exacerbation of bronchiectasis?
Person with bronchiectasis with a determination in 3+ key symptoms for at least 48hrs:
Cough Sputum volume/ consistency Sputum purulence Breathlessness/ exercise tolerance Fatigue Haemopytosis
What is the most common identifiable cause of bronchiectasis in the Uk?
Cystic fibrosis
What is the pathology of cystic fibrosis?
Autosomal recessive 1/2500 UK
Chromosome 7 mutation causing deflation of phenylalanine leads to an abnormal function of the epithelial chloride channel (cystic fibrosis transmembrane conductance regulator) CFTR key role in maintaining lung epithelium function and normal epithelial function in other body organs e.g pancreas (malabsorption), liver (biliary cirrhosis), sweat glands (heat shock), vas deferens (infertility), disrupts ENAC so Na resorption control
Defective CFTR reduces airway surface liquid hydration which leads to thick and sticky mucus and impaired NUCO-ciliary clearance
What are the most common mutations relating to the CFTR channel that can occur?
Over 2000 mutations (not all pathogenic)
- manufacture CFTR protein
- transportation CFTR (most common)
- Protein doesn’t work
- protein partially active
- reduction in protein/ mRNA synthesis
- partially unstable
What are the criteria for diagnosing cystic fibrosis?
One+ characteristic features OR history CF sibling OR positive newborn screening
AND
Increased sweat chloride conc >60mmol/l (sweat test) OR identification 2 CF mutations
Main CF clinical presentations
- Meconium ileus (obstruction of ileum with thicker than normal meconium) 15-20% newborn CF infants (bilious vomiting, abdo distension, delay in passing meconium =poo)
- Intestinal malabsorption - >90% CF intestinal malabsorption (deficiency pancreatic enzymes) - scarring exocrine part -> type 3 diabetes mellitus
- Recurrent chest infections
- Newborn screening
List some complications of Cf
Bronchiectasis
Pneumothorax
Resp failure
Nasal polyposis
Type 3 DM
Pancreatic insufficiency
Distal intestinal obstruction syndrome
Oesophageal reflux
Chronic liver disease
Portal hypertension
Gallstones
Right cardiac failure
Arthritis
Male infertility
Lifestyle advice for Cf patients
No smoking
Avoid others CF (colonisation)/ friends infections
Avoid jacuzzis
Clean and dry nebulisers
Avoid stables and compost
Vaccinations
NaCl tablets in heat/ vigour exercise
Clinical management of Cf
Holistic multi system care
Vaccinations
Cheats physio, infection management
Optimal nutritional state (fat malabsorption can cause V K, E, A! d deficiency)
Children can given feeding tube at night help lung growth
Transplants: lungs, pancreas, liver
What is orkambi?
Two drugs:
Lumacraftor - CFTR chaperone increases number proteins trafficked to cell membrane
-Ivacraftor - CFTR potentiator, improves transport of chloride through ion channel by binding to channels directly and increasing probability of channel being open
Life expectancy for Cf?
Used to be months now 40yrs
By airway clearance 2-3 daily, treating infections, correcting nutrition
