4. Cough Flashcards
Define Bronchiestasis and epidemiology
Permanent dilation of bronchi due to the destruction of the elastic and muscular components of the bronchial wall.It is often caused as a consequence of recurrent and/or severe infections secondary to an underlying disorder
1.06 to 1.3 per 100,000 population in UK
If suspected: When did you first notice the cough?
Do you have any medical conditions that affect your lungs?
Pathophysiology of Bronchiestasis
Neutrophils + T lymphocytes + Immune effector cells –> Cytokines, Proteases and ROS –> dilated airways, lots of mucus –> chronic inflam host response
Common causative organisms (4) of bronchiectasis
H. influenzae
S. pneumoniae
S. aureus
P. aeruginosa
Underlying disorders of bronchiectasis (4 categories)
NB: 7-50% idiopathic
Impaired drainage/clearance (genetic)
Airway obstruction
Defect in host defence
Post infectious
Impaired drainage/clearance (genetic) causes of bronchiectasis
cystic fibrosis, ciliary dyskinesia, alpha 1 anti-trypsin deficiency
Airway obstruction causes of bronchiectasis
Problem inside lumen (foreign body)
Problem in the wall (connective tissue disorder e.g. Rheumatoid Arthritis)
Problem outside (tumour)
Defect in host defence causes of bronchiectasis
immunosuppression, immunodeficiency
Post infectious causes of bronchiectasis
- Childhood respiratory infections due to viruses (i.e., measles, influenza, pertussis)
- Mycobacteriainfection or severe bacterial pneumonia
- Exaggerated response to inhaledAspergillus fumigatus
RF of bronchiectasis
Strong • cystic fibrosis • host immunodeficiency • previous infections • congenital disorders of the bronchial airways • primary ciliary dyskinesia
Weak • alpha-1 antitrypsin deficiency • connective tissue disease • inflammatory bowel disease • aspiration or inhalation injury • focal bronchial obstruction • tall, thin, white females, >60
Symptoms and Signs of bronchiectasis
Symptoms:
- Persistent cough
- Mucopurulent sputum (green or rusty coloured) - 2/3
- SOB
- Haemoptysis (less common - 50%)
Signs:
- Crackles on auscultation (Squeaks and pops on inspiration)
- Presence of underlying disorder
- Fever
AE - change sputum colour and vol
Investigations for bronchiectasis
Observations (Pulse oximetry may show hypoxaemia)
- CXR (first-line): tram track sign (dilated, thickened walls)
- High-resolution CT (gold standard): Signet ring sign/ string of beads sign
- FBC
Neutrophilia = (presence of a superimposed infection or exacerbation)
Eosinophils = aspergillosis - Sputum culture
- Pulmonary function (reduced FEV1, elevated RV/TLC)
Other tests for underlying cause of bronchiectasis
- Serum alpha-1 antitrypsin level
- Sweat sodium chloride concentration and genetic testing for CFTR mutation analysis
- Skin prick test for sensitivity toAspergillus fumigatusfor patients with elevated IgE
Management of bronchiectasis
Exercise, improved nutrition
Airway clearance therapy
- Postural drainage
- Percussion
Inhaled bronchodilator E.g. salbutamol
Inhaled hyperosmolar agent E.g. hypertonic saline –> less inflam med, +ve QoL and sputum bacteriology
Antibiotics in some pts
Prognosis and Complications of bronchiectasis
Prognosis:
Irreversible
Prognosis depends on severity and recurrence of exacerbations.
Complications:
Haemoptysis
Respiratory failure
Cor pulmonale
25 yo F presents to A&E with 2d hx of productive cough, SOB and fever. The cough is worse at night. She’s reported having brought up green mucus for the last 2 days. O/E you hear crackles throughout. On further questioning you find out that she’s been diagnosed with cystic fibrosis at birth and has had these symptoms in the past.
What is the most likely diagnosis? Asthma Pneumonia Chronic sinusitis Bronchiectasis
Bronchiectasis
25 yo F presents to A&E with 2d hx of productive cough, SOB and fever. The cough is worse at night. She’s reported having brought up green mucus for the last 2 days. O/E you hear crackles throughout. On further questioning you find out that she’s been diagnosed with cystic fibrosis at birth and has had these symptoms in the past.
What is the first line investigation for this patient?
Bloods (FBC, CRP)
CXR
CT
Pulmonary function
B because everyone gets CXR with these symptoms
CT is gold standard but only used if you have a high suspicion of Bronchiectasis
Define pneumonia
Inflammation of the alveoli which can be caused by bacteria, viruses or fungi. Inflammation results in air sacs filling with fluid or pus (+blood cells).
Alv. walls thickened by oedema
Pneumonia classification
Pneumonia can be classified by the causative organism or (more commonly) by where it was acquired
- Community Acquired Pneumonia
- Hospital Acquired Pneumonia
- Aspiration Pneumonia
Community Acquired Pneumonia causative organisms
Streptococcus pneumoniae Haemophilus influenzae -------- Staphylococcus aureus group A streptococci
Hospital Acquired Pneumonia causative organisms
Escherichia coli Staphylococcus aureus(MSSA) Klebsiella pneumoniae Acinetobacter baumannii Pseudomonas aeruginosa Enterococcus Faecium
Atypical Pneumonias causative organisms
Mycoplasma pneumoniae
Chlamydophila pneumoniae
Legionella pneumophila
Coxiella burnetii(zootonic pathogen)
50 yo M smoker with multiple comorbidities (diabetes, HTN) presents to A&E with 1d hx of confusion and productive cough with yellow sputum. O/E he is apyrexial, BP 150/95 mmHG, HR 90 bpm, RR of 20 breaths per min. His oxygen saturation is 96% at rest. There are crackles at the left base.
What is the most likely organism that caused this?
Staphylococcus aureus Mycoplasma pneumoniae Streptococcus pneumoniae Pseudomonas aeruginosa Legionella pneumophila
Streptococcus pneumoniae
Pneumonia: 4 mechanisms of entry
Inhalation (viral + atypical)
Aspiration of URT secretions
Haematogenous from local infection (e.g. endocarditis)
Direct extension from local foci (TB via lymphatics)
Signs and Symptoms of pneumonia
Symptoms
- Productive cough
- Coloured sputum
- SOB
- Pain on inspiration
- Pleuritic CP
- Fever (+malaise + rigors)
Signs
- Pyrexia, cyanosis, tachypnoea
- Confusion
- Chest examination: Dull percussion, bronchial breathing on auscultation, decreased chest expansion, increased VRes
Investigations for pneumonia
What 4 things can you tell from a CXR?
Bloods (FBC, CRP) - Neutrophil predominance = bacterial - HCT = severity indicator Sputum sample (Microscopy and culture) Blood cultures (if severe)
CXR
- Consolidation
- Alveolar opacification
- Air bronchograms (air-filled bronchi visible bc surr alv opacifies)
- Lobar vs. multilobar
CURB-65
CURB 65 - Confusion - Urea > 7mmol/L - Resp Rate >30 - BP < 90/60 mmHg - >65 1 point for each
0-1: low severity; home Tx if possible
2: moderate severity; consider hospital Tx
>=3: severe; consider ITU
Mx of pneumonia
- Antibiotics
- Low Severity: oral amoxicillin
- Moderate: oral/IV amoxicillin + macrolide
- High severity: IV Co-Amoxiclav + macrolide - Oxygen (if sats low)
- Analgesics (if pleuritic CP)
- Fluids (if shocked/dehydrated)
Follow up CXR at 6 weeks to check for malignancy, masked by pneumonia.
Prognosis and Complications of pneumonia
Mortality
0-1: < 1%
2: 5-15%
3 or more: 20-50%
Complications:
- Septic shock
- C. difficile infection from antibiotic use
- Death from heart failure, respiratory depression in the elderly or severely unwell.
Atypical Pneumonias definition
Atypical organisms - not detectable on Gram stain and cannot be cultured using standard methods.
Usually gives symptom complex: headache, low-grade fever, cough, and malaise
Constitutional symp > resp findings
Most cases = milder CAP, some, esp. L. pneumophilia –> severe, needs ICU admission
Diseases caused by Legionella
Legionella Pneumonia = Legionnaire’s Disease
Non-pneumatic legionella = Pontiac Fever
Legionella bacteria are found in aqueous environments - transmitted through inhalation of contaminated water dropletse.g. air conditioning, whirlpool spas, contaminated water supplies, recent plumbing work
Legionella presentation
- Prodromal flu-like symptoms (fever, malaise, myalgia)
- Dry cough (can become productive)
- GI symptoms (nausea, D+V)
Legionella investigations
Sputum culture
Urinary antigen detection
Hyponatraemia
CXR – bi-basal consolidation