Respiratory Flashcards
Define pneumonia
Inflammation of the lung parenchyma
Acute low respiratory tract infection
How can pneumonia be anatomically classified?
- Bronchopneumonia = diffuse, patchy infection of different lobes
- Lobar pneumonia = localised consolidation of a single lobe
How can pneumonia be aetiologically classified?
- Community acquired pneumonia = person with no underlying immunosuppression or malignancy
- Hospital acquired pneumonia = >48 hours after hospital admission
- Aspiration pneumonia = acute aspiration of gastric contents into lungs
Briefly describe the pathophysiology of pneumonia
Pathogen colonises pharynx –> translocated to distal airways –> alveolar macrophage response is overwhelmed
Inflammatory response + pathogenic features –> airway exudate and parenchyma damage
What can cause pneumonia to be severe?
- Excessive inflammation
- Lung injury
- Resolution failure
What protective features does the respiratory tract have against pathogens?
Teeth, commensal bacteria, swallowing reflex, mucociliary escalator, coughing, sneezing etc.
Name 3 groups of people who might be at risk of pneumonia
- Elderly
- Children
- COPD patients
- Immunocompromised people
- Nursing home residents
Name 3 pathogens that can cause community acquired pneumonia (CAP)
- Streptococcus pneumoniae
- Haemophilus influenzae
- Mycoplasma pneumoniae
- Staphylococcus aureus
Name 3 pathogens that can cause hospital acquired pneumonia (HAP)
- Pseudomonas aeruginosa
- E.coli
- Klebsiella penumoniae
- Staphylococcus aureus
Name 3 pathogens that can cause pneumonia in immunocompromised patients
- Bacterial pathogens (CAP)
- Fungal - pneumocystis jirovecii (PCP), Aspergillus
- Viral - CMV, adenovirus
What symptoms might you see in someone with pneumonia?
- Fever, sweats and rigors
- Cough +/- rusty sputum
- SOB
- Pleuritic chest pain
- Fatigue and malaise
What signs might you see in someone with pneumonia?
- Raised HR and RR
- Lung consolidation - dull percussion, crackles and wheezes
- Pleural effusion
- Hypoxia
What investigations might you do on someone you suspect has pneumonia?
CXR = consolidation
FBC (WCC )
Biochemistry - LFTs, renal function, U+Es
CRP and ESR = severity
Microbiology - sputum culture, blood culture, serology
How can you assess the severity of community acquired pneumonia?
CURB65 score (1 point for each) - Confusion - Urea >7 mmol/L - RR > 30/min - BP <90/60 mmHg - Age >65 Scores 0-1 = mild 2 = admit to hospital 3-4 = severe, admit and monitor closely 5 = ITU transfer
How can pneumonia be prevented?
Children have pneumococcal vaccine
At risk groups have pneumococcal and influenza vaccination
Smoking cessation
What is the treatment for someone with mild CAP (CRUB65 score 0-1)?
Amoxicillin OR clarithromycin
What is the treatment for someone with moderate CAP (CRUB65 score 2)?
Amoxicillin AND clarithromycin
What is the treatment for someone with severe CAP (CRUB65 score 3-5)?
IV co-amoxiclav AND clarithromycin
What is the treatment for someone with Legionella pneumoniae?
Fluoroquinolone + clarithromycin
What is the treatment for someone with Pseudomnoas aeruginosa pneumonia?
IV ceftazidime + gentamicin
What is the treatment for early onset HAP?
Metronidazole OR beta lactam + beta lactase inhibitor
What is the treatment for late onset HAP?
Linezolid/vancomycin OR IV colistin
A 66 y/o patient presents to you with fever and a productive cough. On examination you notice they are their confused. Their vital signs are: RR - 35; BP - 80/55 and HR: 130. You measure their urea and it comes back at 8mmol/L
a) What is this patients CURB65 score?
b) Where should they be treated?
c) Describe the treatment for this patient
a) Their CURB65 score is 5
b) This patient should be treated in hospital and admitted to critical care
c) The patient should be given IV co-amoxiclav and clarithromyocin
Give 3 potential complications of pneumonia
- Respiratory failure
- Hypotension
- Empyema
- Lung abscess
What is empyema?
Pus filled cavities
Give 3 signs of empyema
- WBC/CRP don’t settle with Abx
- Pain on deep inspiration
- Pleural collection
What is the treatment for empyema?
Drainage
Give 3 risk factors for lung abscess
- Aspiration
- Alcoholics
- Poor dental hygiene
- Bronchial obstruction
How is a lung abscess treated?
Surgical drainage and antibiotics
Define bronchiectasis
Chronic infection of the bronchi/bronchioles leading to permanent dilation and thinning of the airways
Describe the pathophysiology of bronchiectasis
Failed mucociliary clearance and impaired immune function –> microbes easily invade and cause infection –> inflammation –> progressive lung damage
Bronchitis –> bronchiectasis –> fibrosis
What can cause bronchiectasis?
- Congenital = CF
- Idiopathic (50%)
- Post infection - pneumonia, TB, whopping cough
- Bronchial obstruction
- RA
- Hypogammaglobulinaemia
Which bacteria might cause bronchiectasis?
- Haemophilus influenza (children)
- Pseudomonas aeruginosa (adults)
- Staphylococcus aureus (neonates often)
Give 3 symptoms of bronchiectasis
- Chronic productive cough
- Purulent sputum
- Intermittent haemoptysis
- Dyspnoea
- Fever, weight loss
Give 3 signs of bronchiectasis
- Finger clubbing
- Coarse inspiratory crepitate (crackles)
- Wheeze
What investigations might you do on someone to determine whether they have bronchiectasis?
CXR = dilated bronchi with thickened walls
High resolution CT = bronchial wall dilation
Spirometry = obstructive lung disease
Sputum culture
Describe the treatment for bronchiectasis
- Antibiotics
- Anti-inflammatories
- Bronchodilators
- Chest physio
- Surgery = lung resection or transplant
Give 3 possible complications of Bronchiectasis
- Pneumonia
- Pleural effusion
- Pneumothorax
A lady who has recently had pneumonia presents to you with SOB and chronic cough. She is producing copious amounts of purulent sputum. What is the likely diagnosis?
Bronchiectasis
Describe the pathogenesis of Cystic fibrosis
AR defect in chromosome 7 coding (commonly F508) CFTR protein
Cl- transport affect
Decrease Cl secretion and increase Na reabsorption –> increase H2O reabsorption –> thickened mucus secretion
What are the main systemic consequences of CF?
Pancreatic insufficiency = dehydrated secretion –> enzymes stagnation
GI = intraluminal water deficiency –> concentrated bile
Resp = thick mucus can’t be cleared –> infection risk and inflammatory damage
How is CF passed on?
Autosomal recessive condition
How does neonate present with CF?
- Failure to thrive
- Meconium ileus (sticky intestine)
- Rectal prolapse
How do children/young adults present with CF?
- Cough and wheeze
- Recurrent infections
- Haemoptysis
- Pancreatic insufficiency
- Malabsorption
- Male infertility
What are 3 possible respiratory complications of CF?
- Pneumothorax
- Respiratory failure
- Cor pulmonale
- Bronchiectasis
Give 3 signs of CF
- Clubbing
- Cyanosis
- Bilateral coarse crepitations
Name 3 associated conditions with CF
- Osteoporosis
- Arthritis
- Vasculitis
What investigations might you do to diagnose cystic fibrosis?
Sweat test = Na and Cl < 60 mmol/L
Genetic screening for common mutations
Faecal elastase - tests pancreatic enzyme function
Absent vas deferent and epididymis (males)
Microbiology
Spirometry
What is the management of CF?
- Physical therapies (airway clearance) and surveillance
- Antibiotics for infections and prophylaxis
- Bronchodilators
- Pancreatic enzymes replacement (creon)
- ADEK vitamin supplements
- Screening for consequent conditions - osteoporosis
- Bilateral lung transplant
- Vaccinations - flu and pneumococcal
Infection with a gram negative bacteria is a particular concern in patients with CF. What is this organism and how can infection be prevented?
- Pseudomonas Aeruginosa
- Nebulised anti-pseudomonal antibiotic therapy and regular sputum cultures
Malignant bronchial tumour can be divided into 2 groups, what are they?
- Non small cell lung carcinoma (80%)
2. Small cell lung carcinoma (20%)
What type of malignant bronchial tumour tends to have a worse prognosis?
Small cell lung carcinomas - often metastasise
From what cells are small cell carcinomas derived from and what is the significance of this?
Neuroendocrine cells
Can secrete peptide hormones - ACTH, PTHrP, ADH, HCG
Give 3 main cell types the make up non-small cell lung cancers
- Squamous cell (20%) - arise from epithelial cells + associated with keratin production
- Adenocarcinoma (40%) - originate from mucus-secreting glandular cells
- Large cell
Name 3 types of benign lung cancer
- Hamartoma
- Lipoma
- Chondroma
- Leiomyoma
Give 4 causes of lung cancer
- Smoking = main cause
- Asbestos
- Radon
- Coal products
- Chromium
- Arsenic
Which type of NSCC is most common in smokers?
Squamous cell carcinoma
Which type of malignant bronchial tumour fits into TNM staging?
Non small cell carcinoma
What does TNM stand for in lung cancer?
T = size/invasion = T1 (<3cm) --> T2 (>3cm) --> T3 (chest wall/diaphragm) --> T4 (heart + vessels) N = nodal involvement = N1 (hilar) --> N2 (ipsilateral mediastinal) --> N3 (contralateral mediastinal) M = metastases = M0 (no metastases) --> M1 (metastases)
Name 4 places lung cancer can metastasise to
- Bone
- Brain
- Lymph nodes
- Liver
- Adrenal
Name 4 cancers that can metastasise to the lungs
- Breast
- Prostate
- Colorectal
- Melanoma
- Thyroid
- Lymphoma
- Kidney
Give 4 symptoms of local disease lung cancer
- Chest pain
- SOB
- Haemoptysis
- Cough
Give 4 symptoms of lung cancer that has metastasised
- Bone pain
- Headaches
- Abdominal pain
- Seizures
- Confusion
- Weight loss
What are paraneoplastic syndromes?
Disorders triggered by immune response to a neoplasm
Give 3 examples of paraneoplastic syndromes due to lung cancer
- Anorexia
- Weight loss
- Finger clubbing (hypertrophy pulmonary OA)
- Hypercalcaemia
Name 3 differential diagnosis’s of lung cancer
- Oesophageal varices
- COPD
- Asthma
- Pneumonia
- Bronchiectasis
What investigations might you done on someone to determine whether they have lung cancer?
CXR = consolidation or collapse CT scan = tumour staging Bronchoscopy = biopsy PET scan Bloods
How does PET scanning work?
FDG is taken up by rapidly dividing cells
Tumour therefore appear ‘hot’ on the scan
What can cause:
a) false positive
b) false negative
on a PET scan?
a) Infection and inflammation
b) Small lesions
What tests might you do on a patient with lung cancer to determine whether they’re fit for an operation?
- ECG
- Lung function tests
- Determine performance status
What is the treatment for NSCLC?
Prevention = smoking cessation and avoid enivronemtnal carcinogens
Stage 1-2 = resection –> radio + chemo
Stage 3-4 = chemo + radio –> palliative care
What is the treatment for SCLC?
Limited disease = chemo + radio
Extensive = palliative chemo + care
Why is the 5 year lung cancer survival rate so low?
Only 8-10%
Often present very late, so treatment is much harder
Give 4 possible complications of lung cancer
- SVC obstruction
- ADH secretion –> SIADH
- ACTH secretion –> Cushing’s
- Serotonin secretion –> carcinoid
- Peripheral neuropathy
- Pathological fractures
- Hepatic failure
What does the medullas detect?
The pH (H+ conc) of the CSF
What do carotid and aortic bodies detect?
Chemoreceptors respond to increased CO2 and decreased O2 levels
What is type 1 respiratory failure?
Hypoxia = low PaO2
PaCO2 is normal or low due hyperventilation
What is type 2 respiratory failure?
Hypoxia and hypercapnoea = Low PaO2 and increase PaCO2
There is alveolar hypoventilation (CO2 enters alveoli, but not removed)
Give 3 signs of hypercapnoea
- Bounding pulse
- Flapping tremor
- Confusion
- Drowsiness
- Reduced consciousness
What can cause type 1 respiratory failure?
- Airway obstruction
- Failure of O2 to diffuse into the blood
- V/Q mismatch
- Alveolar hypoventilation
What can cause type 2 respiratory failure?
Alveolar hypoventilation
Give examples of diseases that can obstruct the airway (could lead to type 1 respiratory failure)
- COPD
- Asthma
- Obstructive sleep apnoea
Name 3 things that lead to alveolar hypoventilation (could lead to type 1 and type 2 respiratory failure)
- Emphysema
- Obesity
- Neuromuscular weakness - MND
- Chest wall deformity
- Opiates
Give examples of diseases that lead to a failure of O2 to diffuse into the blood (could cause type 1 respiratory failure)
- Interstitial lung disorders - pulmonary fibrosis, sarcoidosis
- Emphysema
Give examples of diseases that lead to V/Q mismatch (could cause type 1 respiratory failure)
- Cardiac failure
- Pulmonary embolism
- Shunts
- Pulmonary hypertension
Give 4 signs and symptoms of type 1 respiratory failure
= Hypoxia
- Cyanosis
- Tachypnoea
- Tachycardia
- Hypotension
- Confusion
- Dyspnoea
Give 4 signs and symptoms of type 2 respiratory failure
- Dyspnoea
- Anxiety
- Orthopnoea
- Disturbed sleep
- Frequent chest infections
- Confusion
- Flapping temor
- Bounding pulses
What treatments might be given for V/Q mismatch?
Ventilation support - CPAP, BIPAP
What is continuous airway pressure (CPAP)?
Ventilation support given to people with obstructive sleep apnoea
Improves gaseous exchange
What is bilevel positive airway pressure (BIPAP)?
Ventilation support given to those who have had acute exacerbation of COPD
Improves ventilation to perfused alveoli - pressure decreases when breathing out, and increases when breathing in
What happens to the FEV1, FVC and FEV1/FVC ratio in an obstructive lung disease?
FEV1 < 80% predicted
FVC = normal
FEV1/FVC ratio <0.7
What happens to the FVC and FEV1/FVC ratio in a restrictive lung disease?
FVC = reduced
FEV1/FVC ratio = normal
If the trachea, bronchi and bronchioles are involved in a disease process, is this likely to be an obstructive or a restrictive disease?
Obstructive
If the lung parenchyma are involved in a disease process, is this likely to be an obstructive or a restrictive disease?
Restrictive
If the chest wall is involved in a disease process, is this likely to be an obstructive or a restrictive disease?
Restrictive
Give an example of a reversible obstructive lung disease
Asthma
Give an example of a irreversible obstructive lung disease
COPD
What is the effect of COPD on residual volume and total lung capacity?
RV and TLC are increased
Give an example of a restrictive lung disease
Pulmonary fibrosis
Is total lung capacity increased or decreased in restrictive lung diseases?
Decreased
Is total lung capacity increased or decreased in obstructive lung diseases?
Increased
Define inspiratory reserve volume (IRV)
The additional volume of air that can be forcibly inhaled after a tidal volume inspiration
Define expiratory reserve volume (ERV)
The additional volume of air that can be forcibly exhaled after a tidal volume expiration
Define forced vital capacity (FVC)
The maximum volume of air that can be forcibly exhaled after maximal inhalation
Define total lung capacity (TLC)
The vital capacity plus the residual volume. It is the maximum amount the lungs can hold
TLC = VC + RV
TLC = TV + FRC + IRV
Define residual volume (RV)
The volume of air remaining in the lungs after a maximal exhalation
Define functional residual capacity (FRC)
The volume of air remaining in the lungs after a tidal volume exhalation
FRC = ERV + RV
Define tidal volume (TV)
The volume of air moved in and out of the lungs during a normal breath
Normal = 500ml
Define FEV1
The volume of air that can be forcibly exhaled in 1 second
Define peak expiratory flow (PEF)
The greatest rate of airflow that can be obtained during forced expiration. Age, sex and height can all affect PEF
What is the transfer coefficient?
The ability of O2 to diffuse across the alveolar membrane
How can you find the transfer coefficient?
Inspired small amount of CO then hold breath for 10 seconds at total lung capacity then gas transferred is measured
Name 3 disease that might have a low transfer coefficient
- Emphysema
- Anaemia
- Fibrosis alveolitis
- Pulmonary hypertension
- Pulmonary fibrosis
- COPD
Name a disease that might have a high transfer coefficient
Pulmonary haemorrhage
What is consolidation on a CXR?
Regions of lung filled with liquid
Area appear white - dense
What might be released on mast cell degranulation?
- Pre-formed histamine
- Newly synthesised eicosanoids - cysteine leukotrienes and prostaglandin D2
- Cytokines - IL-3,4,5
What is IL-5 responsible for?
Pro-inflammatory and eosinophil survival
What is IL-3 responsible for?
Increases the number of mast cells
What is IL-4 responsible for?
IgE synthesis
What is the eicosanoid pathway?
Phospholipid –> arachidonic acid (by phospholipase A2) –> leukotrienes (by 5-lipooxygenase) or prostaglandins (by Cyclooxygenase)
What are the lung mast cell mediators that are responsible for bronchoconstriction?
Cysteine leukotrienes and histamine
What are the lung mast cell mediators that are responsible for inflammation?
Cysteine leukotrienes, cytokines and histamine
What are the lung mast cell mediators that are responsible for airway remodelling?
Cysteine leukotrienes, cytokines and enzymes
Describe asthma
Episodic, reversibile airway obstruction due to bronchial hyperactivity to a variety of stimuli
What are the 3 characteristic features of asthma?
- Airflow obstruction
- Hyper-responsive airways to a range of stimuli
- Bronchial inflammation
Give 3 reasons why the airways are hyperactive in asthmatics
- Inflammatory infiltrate
- Eosinophils
- Epithelium destruction gives easier access to bronchoconstrictors
What is the mechanism behind hyper-reactivity?
Neurogenic inflammation
Describe neurogenic infalmmation
Sensory nerve activation initiates impulses –> stimulates CGRP (pro-inflammatory) –> activated mast cells and innervates goblet cells
Describe the process of airway remodelling in asthma
- Hypertrophy and hyperplasia of smooth muscle cells narrow the airway lumen
- Deposition of collagen below the BM thickens the airway wall
- Eosinophils play a role
What type of T cell is involved in asthma?
CD4+
What 2 categories can asthma be divided into?
- Allergic asthma (extrinsic), atopic, IgE and mast cell involvement
- Non allergic asthma (intrinsic)
Define atopy
The tendency to develop IgE mediated response to common aeroallergens
What is allergic asthma?
When an innocuous allergen triggers an IgE mediated response
Immune recognition processes are faulty –> increase IgE, IL3,4,5, production
What is non-allergic asthma?
Airway obstruction induced by exercise, cold air and stress
Extrinsic asthma: what happens when IgE binds to mast cells?
Vasoconstrictive substances are released causing bronchoconstriction, oedema, bronchial inflammation and mucus hyper-secretion
Name 4 factors that can exacerbate asthma
- Allergens
- Viral infection
- Cold air
- Exercise
- Stress
- Cigarette smoke
- Drugs - NSAIDs/BB
What occupations can be associated with an increase risk of developing asthma?
- Paint sprayers
- Animal breeders
- Bakers
- Launder workers
What other atopic conditions are associated with asthma?
Eczema
Hayfever
What are the symptoms of asthma?
- Episodic cough
- Expiratory wheeze
- SOB
- Diurnal variation - often worse in morning
- Chest tightness
What are the signs of asthma?
- Tachypnoea
- Audible wheeze
- Widespread polyphonic wheeze
- Cough
What are the signs of an acute asthma attack?
- Can’t complete sentences
- HR > 110 bpm
- RR > 35/min
- PEF < 50% predicted
What are the signs of a life threatening asthma attack?
- Hypoxia = PaO2 <8 kPa, SaO2 <92%
- Silent chest
- Bradycardia
- Confusion
- PEF < 33% predicted
- Cyanosis
Give 3 differential diagnosis’s of asthma
- COPD
- Bronchial obstruction
- Pulmonary oedema
- Pulmonary embolism
- Bronchiectasis
What investigations might you do someone to determine whether they have asthma?
- PEFR
- Spirometry = obstructive
- CXR
- Atopy = skin prick, RAST
- Bloods = high IgE, Eosinophils
How can reversibility be tested in asthma?
When given a beta agonist there will be a 400ml increase in FEV1 OR a 20% improvement in PEFR
What are the 2 principles of asthma treatment
- Alleviate symptoms
2. Target inflammation
Describe the management of asthma
Improve control and avoid trigger Smoking cessation Beta agonist = symptomatic relief Inhaled corticosteroid = anti-inflammatory Steroids
What is the guideline mediation regime for asthma?
- SABA
- SABA + inhaled corticosteroid
- LABA
- Oral corticosteroid
- Anticholinergics + theophylline
What broad class of drugs are commonly used to alleviate asthmatic symptoms?
Bronchodilators
What broad class of drugs are commonly used to reduce inflammation in asthmatics?
Steroids
Name 2 types of bronchodilators that are commonly used in asthma
- Beta agonist
2. Muscarinic antagonists
What type of beta adrenergic receptors are found in the lungs?
Beta 2
Describe how beta 2 agonists work?
Beta 2 interacts with Gs –> activation of adenylate cyclase –> ATP to cAMP –> PKA synthesis –> bronchodilation
Give 2 functions of cAMP
- Stabilisation of mast cells, inhibit mast cell mediator release
- Relaxes airway smooth muscle
Give an example of a short acting beta 2 agonist (SABA)
Salbutamol
Last 4 hours
Give an example of a long acting beta 2 agnosia (LABA)
Salmeterol, formoterol
Last 12 hours
What makes LABA long acting?
They have increased lipophilicity
How do muscarinic antagonist work?
Prevent M3 receptor activation –> reduction in Ca2+ activation –> less MLC kinase –> reduced muscle contraction
Block bronchoconstriction
Give an example of a muscarinic antagonist
Atropine, ipratropium bromide, tiotropium bromide
Where are anti-inflammatory steroids produced?
Adrenal cortex
How do glucocorticoids work?
Interfere with gene transcription to suppress inflammation
Give an example of an inhaled corticosteroid
Beclomethasone, budesenide
What is the advantage of having inhaled medication in the management of asthma?
More likely to reach target site and there is reduced chance of side effect
Give 3 potential side effect of inhaled corticosteroid use
- Adrenal suppression
- Osteoporosis
- Cataracts
- Glaucoma
Effects of steroids: what is the effect of a positive GRE?
= increased transcription
Increase lipocortin production - anti-inflammatory as it inhibits phospholipase A2
Effects of steroids: what is the effect of a negative GRE?
= suppression of cytokines
Give 3 possible complications of asthma
- Exacerbation
- Pneumothorax
- Pneumonia
Define COPD
Progressive obstructive disorder (FEV1/FC < 70%) that is irreversible
What can COPD be sub-divided into?
- Chronic bronchitis
2. Emphysema
What is the clinical diagnosis of chronic bronchitis?
Cough/sputum for >3 months in 2 consecutive years
Describe the pathophysiology of chronic bronchitis
Airway inflammation –> fibrosis and luminal plugs –> decreased alveolar ventilation
Would a patient with chronic bronchitis be a ‘pink puffer’ or a ‘blue bloater’?
Blue bloater
Patient have low PaO2 and high PaCo2 –> cyanosis –> cor pulmonale
Cyanosis = blue
Describe the pathophysiology of emphysema
Dilation and destruction of the lung tissue distal to the terminal bronchioles
Enlarged alveoli + loss of elastic recoil = increased alveolar ventilation
Would a patient with emphysema be a ‘pink puffer’ or a ‘blue bloater’?
Pink puffer
Breathless but not cyanosed
Type 1 respiratory failure
Normal or near normal PaO2 and normal or low PaCO2
What are the main cells responsible for inflammation in COPD?
Neutrophils and macrophages
What type of T cell is involved in COPD?
CD8+
What can cause COPD?
- Genetic = alpha 1 antitrypsin deficiency
- Smoking
- Air pollution
- Occupational factors = dust, chemicals
Name 4 symptoms of COPD
- Dyspnoea
- Cough +/- sputum
- Expiratory wheeze
- Weight loss
Give 4 signs of COPD
- Tachypnoea
- Barrel shaped chest
- Hyperinflantion
- Cyanosis
- Pulmonary hypertension
- Cor pulmonale
Give 3 differential diagnosis’s for COPD
- Asthma
- HF
- Pulmonary embolism
- Bronchiectasis
- Lung cancer
What investigations might you do to diagnose someone with COPD?
CXR = hyperinflation, flat hemi-diaphragms, large pulmonary arteries CT = Bronchial wall thickening, enlarged air spaces ECG = RA and RV hypertrophy ABG = decreased PaO2 +/- hypercapnia
How can spirometry stage COPD?
Stage 1 = FEV1 <80% of predicted value
Stage 2 = FEV1 50-79% of predicted value
Stage 3 = FEV1 30-49% of predicted value
Stage 4 = FEV1 <30% of predicted value
Give 3 factors that can be used to establish a diagnosis of COPD
- Progressive airflow obstruction
- FEV1/FVC ratio < 0.7
- Lack of reversibility
What are the treatments for COPD?
Smoking cessation Pulmonary rehabilitation SABA/LABA = symptomatic relief Inhaled corticosteroids Muscarinic antagonist Long term O2 therapy Alpha 1 antitrypsin replacement if due to deficiency
Give 3 advantages and 1 disadvantage of using ICS in the treatment of COPD?
Advantages
1. Improve QOL
2. Improve lung function
3. Reduce the likelihood of exacerbations
Disadvantages:
1. There is an increased risk of pneumonia
Give 3 possible complications of COPD
- Exacerbations
- Infection
- Respiratory failure
- Cor pulmonale
- Pneumothorax
Define exacerbation
An acute event characterised by worsening symptoms beyond normal day to day variation
Give 2 potential consequences of exacerbations of COPD/asthma
- Worsened symptoms
- Decreased lung function
- Negative impact of QOL
- Increased mortality
- Huge economic cost
What is the likely cause for an exacerbation of COPD?
Viral URTI
Bacterial infections
What are the aims of treatment for exacerbations of COPD?
- Minimise the impact of the current exacerbation
2. Prevent subsequent exacerbations
What is the treatment for an exacerbation of COPD?
- Oxygen
- Bronchodilators
- Systemic steroids
- Antibiotics if there is breathlessness and sputum production
Give 3 ways in which subsequent exacerbations be prevented
- Smoking cessation
- Vaccination
- LABA/LAMA/ICS
A young person presents to you with breathlessness, wheeze and cough. There appears to be inflammation of the airways. When you do a spirometry test the results are variable. You ask the patient to do a peak flow diary and the results of this show diurnal variation. Is the patient likely to have asthma or COPD?
Asthma
Although breathlessness, wheeze and cough are symptoms of both asthma and COPD the fact that the spirometry results are variable is a large indication that this person has asthma!
The patient is also young and COPD tends to be more common in older people
An older person presents to you with breathlessness, wheeze and cough. There appears to be inflammation and fibrosis of the airways and also alveolar disruption. You ask the patient to do a peak flow diary and the results of this are all abnormal. Is the patient likely to have asthma or COPD?
COPD
Although breathlessness, wheeze and cough are symptoms of both asthma and COPD the fact that the spirometry results are consistently abnormal is a large indication that this person has COPD; in asthma there would be diurnal variation. Fibrosis and alveolar disruption are also signs of COPD and the fact that the patient is an older patient also makes COPD the more likely diagnosis
Where might an emboli arise form to cause a pulmonary embolism?
Dislodged DVT
Name 5 risk factors for a pulmonary embolism
- Recent surgery
- Immobilisation
- Oestrogen = HRT, OCP, pregnancy
- Malignant
- Hypertension
- Smoking
- Anti-phospholipid syndrome
What is the consequence of a small, peripheral PE?
Infarction
Ventilation but no perfusion = dead space
What is the consequence of a large, central PE?
Ischaemia
Resistance to flow –> RHF
Give 3 symptoms of a PE
- Dyspnoea
- Pleuritic chest pain
- Haemoptysis
Give 3 signs of a PE
- Tachycardia
- Tachypnoea
- Pleural rub/effusion
- Cyanosis
- Signs of DVT = red, swollen leg
What investigations mighty you in someone to determine whether they have a PE?
ECG = tachycardia, RBBB V/Q scan = mismatch defect Bloods - D-dimer Doppler US ABG = type 1 respiratory failure CT pulmonary angiography
What is D dimer?
A small protein fragment found in blood after a blood clot is degraded by fibrinolysis
Negative D dimer = excludes PE
What does the Wells scoring system use to work out the probability of someone having a PE?
- Clinical signs/symptoms of DVT
- HR > 100bpm
- Recent immobilisation
- Previous DVT/PE
- Haemoptysis
- Malignancy
Score >4 - PE likely
Describe the treatment for PE
- Thrombolysis
- LMWH and oral warfarin
- NOAC
- Analgesia
- Oxygen
What disease might be in the differential diagnosis of PE?
- Asthma
- COPD
- Pneumonia
- MI
How can you prevent a PE?
Compression stockings
Early mobilisation
LMWH prophylaxis
Give 3 functions of pleura
- Allows movement of the lung against the chest wall
- Coupling system between the lungs and chest wall
- Clearing fluid from the pulmonary interstitium
What does the pleural fluid contain?
Protein - albumin, globulin, fibrinogen
Mesothelial cells, monocytes and lymphocytes
How much fluid is contained within the healthy pleural space?
15ml
What produces and reabsorbs pleural fluid?
Parietal pleura
Name 3 diseases associated with the pleura
- Pleural effusion
- Pneumothorax
- Pleural plaques
Define pleural effusion
Excess fluid in the pleural space
Name the types of pleural effusion
- Transudate = extravascular fluid with low protein content (<25 g/L)
- Exudate = protein rich fluid (>35 g/L)
- Chylothorax = lymph in pleural cavity
Name 3 causes of a transudate pleural effusion
- Heart failure
- Hypoalbuminaemia
- Peritoneal dialysis
- Constrictive pericarditis
Name 3 causes of a exudate pleural effusion
- Pneumonia
- Malignancy
- PE with infarction
Name 2 causes of a chylothorax pleural effusion
- Neoplasm
- Trauma
- TB
- Sarcoidosis
How does a pleural effusion present?
- Dyspnoea
- Pleuritic chest pain
- Reduced chest wall movement
- Dull percussion
- Absent breath sounds
How might you diagnose a pleural effusion?
CXR = blunt costophrenic angles
Thoracentesis
How would you treat a transudate pleural effusion?
Treat the underlying cause
How would you treat a exudate pleural effusion?
Drainage
What can you do if recurrent pleural effusions occur?
Pleurodesis (stick pleura together)
What is a pneumothorax?
Accumulation of air in the pleural space which can lead to partial or complete lung collapse
How can pneumothorax be classified?
Primary = thin, young men = caused by trauma, congenital pleura rupture Secondary = associated with chronic lung diseases, infections and malignancies
How does a pneumothorax present?
- Sudden onset dyspnoea and pleuritic chest pain
- Reduced expansion
- Hyper-resonant percussion
- Diminished breath sounds
What investigation might you do in someone you suspect to have a pneumothorax?
CXR = translucency and collapse
What is the treatment for a pneumothorax?
Drainage
Oxygenation if hypoxic
Pleurodesis if recurrent
Name a possible complication of a pneumothorax
Tension pneumothorax
Describe the pathophysiology of a tension penumothorax
Pleural tear creates 1 way valve - air only goes into cavity –> increased unilateral pressure –> respiratory distress, shock and cardiac arrest
What is the treatment for a tension pneumothorax?
Immediate needle decompression
Chest drain insertion
NO CXR
Define interstitial lung diseases
Distant cellular infiltrate and extracellular matrix deposition in lung distal to the terminal bronchioles - disease of the alveolar/capillary interface
What are 5 major categories of interstitial lung disease
- Associated with systemic disease - rheumatological
- Environmental aetiology - fungal, dusts
- Granulomatous disease - sarcoidosis
- Idiopathic - idiopathic pulmonary fibrosis
- Other
What are the 4 major features of interstitial lung disease?
- Cough
- Dyspnoea
- Restirictve spirometry
- Abnormal CXR/CT
Would pulmonary function tests taken from someone with interstitial lung disease show a restrictive or obstructive pattern?
Restrictive
Decreased gas transfer and a reduction in PaO2
What is the pathology of interstitial lung disease?
Increased fibrous tissue within the lung parenchyma resulting in increased stiffness and decreased expansion
What kind of disease is sarcoidosis?
Granulomatous disease
Describe the pathophysiology of sarcoidosis
Chronic inflammation –> non-caseating granuloma in various body sites
Focal accumulation of epithelia cells, macrophages and lymphocytes (mainly T cells)
Describe the epidemiology of sarcoidosis
Women > men
Aged 20-40 years old
Give 3 pulmonary symptoms of sarcoidosis
- Dry cough
- Progressive SOB
- Wheeze
- Chest pain
What is the effect of sarcoidosis on the skin?
Erythema nodosum
What is the effect of sarcoidosis on the eyes?
Uveitis
What is the effect of sarcoidosis on the bone?
Arthralgia
What is the effect of sarcoidosis on the liver?
Hepatosplenmeagly
What investigations might you do in someone who you suspect to have sarcoidosis?
Bloods = increase ESR, lymphopenia, increase CAE, raised LFTs
Bronchoalveolar lavage = increased lymphocytes
Lung biopsy = diagnostic = non-caseating granulomata
CXR = staging
How can you stage sarcoidosis?
Using CXR
Stage 1 = bilateral hilar lymphadenopathy
Stage 2 = pulmonary infiltrates with BHL
Stage 3 = pulmonary infiltrates without BHL
Stage 4 = progressive pulmonary fibrosis, bulla formation and bronchiectasis
How do you treat acute sarcoidosis?
NSAIDs and bed rest
How do you treat sarcoidosis if there are pulmonary infiltrates?
Prednisolone
+/- immunosuppression
Give 2 possible differential diagnosis’s for sarcoidosis
- Lymphoma
2. Pulmonary TB
What is idiopathic pulmonary fibrosis?
Progressive fibrosis in the alveoli that limits the patients ability to respire
Describe the pathophysiology of idiopathic pulmonary fibrosis
Fibroblast proliferation + collagen formation –> restrictive lung disease
Give 3 causes of idiopathic pulmonary fibrosis
- Occupational = coal, asbestos
- Smoking
- Idiopathic
Give 4 signs and symptoms of idiopathic pulmonary fibrosis
- Dry cough
- SOB on exertion
- Systemic = malaise, weight loss, arthralgia
- Cyanosis
- Finger clubbing
- Inspiratory crackles/crepitus
What investigations might you do in someone you suspect to have idiopathic pulmonary fibrosis?
ABG = type 1 respiratory failure
Bloods = raised CRP, immunoglobulins and check autoantibodies
CXR/CT = degreased lung volume + honeycomb lung
Spirometry = restrictive
Lung biopsy = confirmation
What is the treatment for idiopathic pulmonary fibrosis?
Lung transplant
Supportive care = oxygen, pulmonary rehab, pain relief
Pirfenidone = antifibrotic agent
Give 2 possible complications of idiopathic pulmonary fibrosis
- Respiratory failure
2. Cor pulmonale
What is hypersensitivity pneumonitis (EAA)?
Allergic response to inhaled antigen –> type 3 hypersensitivity reaction –> inflammatory response in alveoli and small airways
In hypersensitivity pneumonitis (EAA), what can chronic exposure lead to?
Granuloma formation and obliterative bronchiolitis
Name 3 causes of hypersensitivity pneumonitis (EAA)
- Farmers lung - mould hay
- Bird/pigeon fancier’s lung - proteins in droppings
- Malt-workers lung
- Cheese workers lung
Give 3 symptoms of acute hypersensitivity pneumonitis (EAA)
4-6 hours post exposure
- Fever
- Rigors
- Dry cough
- Myalgia
- Dyspnoea
Give 3 symptoms of chronic hypersensitivity pneumonitis (EAA)
- Cyanosis
- Clubbing
- Weight loss
- Increasing dyspnoea
- Type 1 respiratory failure
What investigations might you do in someone you suspect to have hypersensitivity pneumonitis (EAA)?
Bloods = raised WCC, ESR and neutrophilia
CXR = upper zone fibrotic shadow –> honeycomb lung
Spirometry = restrictive
Bronchoalveolar lavage = increase lymphocytes and mast cells
What is the treatment for hypersensitivity pneumonitis (EAA)?
Avoid exposure
Steroids
- acute = prednisolone followed by reduced dose
- choric = long term
What are occupational lung disorders?
Lung disorders due to a response in inhaling something at work - fumes, dust, gas, aerosol
Give 4 damage mechanisms of occupational lung disorders
- Direct injury
- Infection
- Allergy (e.g. EAA)
- Chronic inflammation (e.g. COPD)
- Destruction of lung tissue (e.g. emphysema)
- Lung fibrosis
- Carcinogenesis
Give an example of an occupational asthma
Baker’s asthma - due to flour
Give 3 ways in which occupational lung disorders can be prevented
- Risk assessment
- Legal requirement
- Prevent and minimise exposure to harmful substances
- Monitor workers health so health problems can be identified early
What are potential consequences of occupational lung disorders?
- Increases morbidity and mortality
2. Loss of income
What is the name of a lung disorder group the reflect inhaled dust/toxins?
Pneumoconiosis
Give an example of pneumoconiosis
Coal workers pneumoconiosis
Silicosis
Asbestos exposure
Extrinsic allergic alveolitis
What is coal workers pneumoconiosis?
Accumulation of dust in lungs and reaction of the tissue to its presence
Describe the pathogenesis of coal workers pneumoconiosis
Dust ingested by alveolar macrophages in small airways –> alveoli die –> release enzymes –> fibrosis
What can the progression of coal workers pneumoconiosis lead to?
Progressive massive fibrosis = apical destruction and disruption of lung –> emphysema + airway damage
What investigations might you do to diagnose progressive massive fibrosis?
CXR = round fibrotic masses in upper lobes
Rheumatoid factor and anti-nuclear antibodies present in serum
What is silicosis?
Inhalation of silica particles –> toxic to alveolar macrophages –> initiated fibrogenesis
Seen in stonemasons, pottery workers and foundry workers
What is shown on a CXR in silicosis?
Diffuse nodular pattern in upper and mid-zone and thin streaks of calcification of hilar nodes
Give 5 potential consequences of asbestos exposure
- Plaques
- Effusion
- Asbestosis
- Mesothelioma
- Bronchial carcinoma
Describe the pathophysiology of asbestosis
Asbestos trapped in lungs –> resistant to macrophage and neutrophil enzymatic destruction –> chronic inflammation –> fibrosis
Give 4 signs and symptoms of asbestosis
- Progressive dyspnoea
- Finger clubbing
- Bilateral basal end-inspiratory crackles
- Pleural plaques (increase risk of mesothelioma and bronchial carcinoma)
Define mesothelioma
A high grade malignancy of the pleura that spreads around the pleural surfaces
What is the main cause of mesothelioma?
Asbestos exposure
What are the signs and symptoms fo mesothelioma?
- SOB
- Cough
- Chest pain
- Finger clubbing
- Weight loss
What investigations might you do on someone to determine whether they have mesothelioma?
CXR/CT scan = pleural effusion and thickening
Pleural biopsy
What is the treatment for mesothelioma?
- Symptom control
2. Palliative chemo or radiotherapy
What is treatment of mesothelioma so difficult?
Incurable as it is resistant to surgery, chemo and radiotherapy
Average time from diagnosis to death = 8 months
How does the treatment between local and systemic lung cancer vary?
Local = surgery and radiotherapy Systemic = chemotherapy
Give 5 side effects of radiotherapy
- Fatigue
- Anorexia
- Cougared
- Oesophagitits
- Systemic symptoms
What are the 3 main aims of palliative chemotherapy?
- Relieve symptoms
- Improve quality of life
- Shrink tumours
Give 4 side effects of chemotherapy
- Alopecia
- Nausea and vomiting
- Peripheral neuropathy
- Constipation or diarrhoea
Define pulmonary hypertension
Increase in mean pulmonary arterial pressure >25 mmHg and secondary right ventricular failure
What can cause an increase in mPAP?
Increase resistance to flow
Increased flow rate
Give 3 causes of pulmonary hypertension
- Congenital heart defects - septal defects
- SLE
- Pulmonary embolism
- Portal hypertension
- COPD
Give 4 symptoms of pulmonary hypertension
Initial 1. Exertional dyspnoea 2. Lethargy 3. Fatigue 4. Syncope After RV failure develops 5. Peripheral oedema 6. Abdominal pain (due to hepatic congestion)
What investigations might you do in someone to determine whether they have pulmonary hypertension?
CXR = enlarged pulmonary arteries
ECG = ventricular hypertrophy
ECHO = right ventricular dilation and/or hypertrophy
Spirometry
Describe the treatment of pulmonary hypertension
- Oxygenation
- Warfarin (for risk of thrombosis)
- Diuretics (for oedema)
- CCB (pulmonary vasodilation)
- Treat underlying cause
Give a possible complication of pulmonary hypertension
Cor pulmonale (RS HF) –> pleural effusion + death
Describe mycobacterium tuberculosis
- Acid fast bacilli
- Has a waxy capsule
- Grows slowly (so hard to culture in a lab)
- Resistant to phagolysomal killing –> granulomatous disease
What mycobacterium can cause abdominal tuberculosis?
Mycobacterium bovis
- found in unpasteurised milk
How is TB transmitted?
Aerosol transmission
Describe pulmonary infection of TB
Bacilli settle in lung apex
Macrophages and lymphocytes mount an effective immune response that encapsulate and contains the organism forever
Describe the pathogenesis of pulmonary TB disease
- Bacilli and macrophages form primary focus
- Mediastinal lymph nodes enlarge
- Primary focus and enlarged lymph nodes = primary complex = Gohn complex
- Granuloma develops into a cavity
- Cavity is filled with TB bacilli = expelled when patient coughs
- Granuloma can rupture –> spread around the body
Describe the disease course of TB
Primary infection –> latent TB –> reactivation/immunocompromised
Where in the lung is granuloma cavity most likely to develop in TB?
Apex of the lung = more air and less blood supply and less immune cells
Give 3 risk factors for TB
- Living in a high prevalence area
- IVDU
- Homeless
- Alcohol
- HIV +ve
What systemic symptoms might you see as a result of TB?
- Weight loss
- Night sweats
- Anorexia
- Malaise
What pulmonary symptoms might you see as a result of TB?
- Cough
- Chest pain
- Breathlessness
- Haemoptysis
Name 3 places where TB might spread to?
- Bone and joint = pain and swelling
- Lymph nodes = pain and discharge
- CNS = TB meningitis
- Biliary TB = disseminated
- Abdominal TB = ascites, malabsorption
- GU TB = sterile pyuria, WBC in GU tract
What investigations might you do to determine whether someone has TB?
Inflammatory markers = raised CRP, hyperalbuminaemia, thromobocytosis, high B cell count
CXR = consolidation, collapse, pleural effusion
Microbiology - sputum/biopsy = Ziehl-Neelson stain and culture
A special culture medium is needed to grow TB, what is it called?
Lowenstein Jenson Slope
What test might you do to diagnose latent TB?
Tuberculin skin test
Intradermal injection –> stimulates type 4 hypersensitivity reaction
What might a lymph node biopsy from someone with TB show?
Caseating granuloma
What is the drug treatment commonly used for TB?
RHZE RH = 6 months ZE = 2 months R = rifampicin H = isoniazid Z = pyrazinamide E = ethambutol
Give 2 potential side effects of Rifampicin
- Red urine
- Hepatitis
- Drug interaction - it’s an enzyme inducer
Give 2 potential side effects of Isoniazid
- Hepatitis
2. Neuropathy
Give 2 potential side effects of Pyrazinamide
- Hepatitis
- Gout
- Neuropathy
Give a potential side effect of Ethambutol
Optic neuritis
Why is compliance so important when taking TB medication?
Resistance and relapse likely if non-compliant
Why does TB treatment need to last 6 months?
Ensure all dormant bacteria have ‘woken up’ and been killed
Give 2 factors that can increase the risk of drug resistance in TB
- If the patient has had previous treatment
- If they live in a high risk area
- If they have contact with resistant TB
- If they have a poor response to therapy
How can TB be prevented?
- Active case finding
- Detect and treat latent TB
- Vaccination = BCG
Name 4 upper respiratory tract infections
- Rhinosinusitis - common cold
- Bacterial sinusitis
- Pharyngitis
- Epiglottitis
- Whooping cough
- Influenza
What are the causative organisms of influenza?
Influenza A (severe outbreaks)
Influenza B
Influenza C
What are the main antigens on influenza A?
Haemagglutinin - grappling hook binds to cell
Neuraminidase - cuts new viruses out of cell
Define antigenic drift
Small mutation and minor antigenic variation
Causes seasonal epidemics
Define antigenic shift
Larger mutations and major antigenic variation
Causes pandemics
How can influenza be transmitted?
Aerosol
Droplet = hand-to-hand
What are the symptoms of influenza?
URTI symptoms = cough, sore throat, runny nose
Systemic = fever, headache, myalgia, weakness
What is the treatment for influenza?
Oxygenation, nutrition and hydration
Treat secondary infection
Antiviral to prevent spread (has no treatment effect)
Name a possible compilations of influenza
Bacterial pneumonia
What factors are there to suggest that future pandemics may be likely?
- More travel
- Increasing world population
- Rise in intensive farming
What can cause the common cold (rhinitis and sinusitis)?
- Rhinovirus
- Coronavirus
What are the symptoms of a common cold?
- Blocked/runny nose
- Sore throat
- Cough
- Sneezing
- Pain, swelling and tenderness around sinuses
What is the management for a common cold?
Watch and wait
Hydration, plenty of sleep and paracetamol
What can cause bacterial sinusitis?
Streptococcus pneumoniae
Haemophilius influenzae
Give 4 symptoms of bacterial sinusitis
- Unilateral pain
- Purulent discharge
- Fever
- Sinus headache
What is the treatment for bacteria sinusitis?
Plenty of rest and hydration
Paracetamol and ibuprofen
Nasal decongestants
Antihistamines
What are 2 possible complications of bacterial sinusitis?
- Brain abscess
2. Sinus vein thrombosis
Is sinusitis normally caused by a bacterial or viral infection?
Viral
Is pharyngitis normally caused by a bacterial or viral infection?
Viral
What can cause pharyngitis?
Viral - Adenovirus, rhinovirus = common - EBV, acute HIV = rare Bacterial - Strep pyogenes
What is the clinical presentation fo pharyngitis?
- Sore throat
- Fever
- Oropharynx and soft palate reddened
- Tonsils inflamed or swollen
- Lymphadenopathy
What is the Centor criteria used for?
To determine the likelihood that a sore throat is bacterial
What signs make up the Centor criteria?
Tonsillar exudate (1 point) Cervical lymphadenopathy (1 point) 38oC fever (1 point) No cough (1 point) Age 3-14 years (1 point) Age >44 years (-1 point) 0-2 = viral infection 3-4 = 50% bacterial infection
What is the main cause of acute epiglottitis?
Haemophilius influenza B
Give 3 symptoms of acute epiglottitis
- Odynophagia (pain on swallowing)
- Inspiratory stridor
- Fever
- Fatigue
- Malaise
What is the management of acute epiglottitis?
Prevention = HiB vaccine
Secure airway
Ceftazidime
What is Whooping cough caused by?
Bordatella pertussis (gram -ve bacilli)
Describe the disease course of whooping cough
7-10 day incubation –> 1-2 week catarrhal stage –> 1-6 week paroxysmal stage
What are the symptoms of whooping cough?
Paroxysmal cough - sudden and severe
Vomiting after cough
What is the treatment of whooping cough?
Clarithromycin
How can you prevent whooping cough?
Pertussis vaccination
8, 12 and 16 weeks and a pre school booster
Give 2 possible complications of whooping cough
- Pneumonia
- Encephalopathy
- Sub-conjunctival haemorrhage
What is ANCA?
Anti-neutrophil cytoplasmic antibody
Autoimmune disorder
What is the mechanism of ANCA?
ANCA activates neutrophils and monocytes
Neutrophils adhere to endothelial cells –> degranulaiton –> free radicals released –> damage endothelium
Further neutrophil recruitment –> inflammation of vessel wall = vasculitis
What disease can be caused by ANCA?
ANCA associated vasculitis
What is Goodpastures syndrome?
Acute glomerulonephritis and pulmonary alveolar haemorrhage and circulating antibodies directed against an intrinsic antigen to basement membrane of kidney and lungs
What are the symptoms of Goodpastures syndrome?
Haemoptysis
Cough
Anaemia
URTI symptoms
What is seen on a CXR of someone with Goodpastures syndrome?
Bilateral lower zone infiltrates (haemorrhage)
How do you treat Goodpastures syndrome?
Immunosuppression (prednisolone) and plasmapheresis
What is Wegener’s granulomatosis?
Necrotising granulomatous inflammation and small vessel vasculitis commonly involved with upper and respiratory tracts and kidneys
What are the symptoms of Wegener’s granulomatosis?
- Rhinorrhoea
- Cough
- Pleuritic chest pain
- Haemoptysis
- Haematuria and proteinuria
What would the serum tests for someone with Wegener’s granulomatosis show?
C-ANCA positive
What is the treatment for Wegener’s granulomatosis?
Glucocorticoids (prednisolone)
+ Immunosuppressive drugs (cyclophosphamide or rituximab)
+ plasma exchange
What is the mechanism behind damage in chronic infection?
Infection won’t clear
Chronic neutrophil recruitment and persistent cellular activation
Pro-inflammatory mediators are released = tissue damage
What is the difference between bronchitis and bronchiolitis?
Bronchitis = inflammation of bronchi epithelium due to irritant and chemical Bronchiolitis = Inflammation of bronchioles and increased mucus secretion due to RSV infection
Respiratory immunity: describe the innate immune repsonse
Mucous, mucociliary escalator, macrophages and neutrophils
Cough reflex and epiglottis closing off trachea on swallowing
Respiratory immunity: describe the adaptive immune response
B cells proudce mainly IgG and IgA antibodies
T cells = CD4, CD8 and regulatory
What can mast cell mediators affect?
Airways = bronchoconstriction
Blood vessels = vasodilation
What are the 3 types of immunosuppression?
- Granulocyte defect - associated with chemotherapy
- B cell defect - associated with rituximab and haematological malignancy
- T cell defect - associated with immunosuppression/HIV
Give 2 examples of iatrogenic suppression
- Corticosteroid use
- Chemotherapy
- Immune suppression after organ transplant
- Rituximab
Give 2 examples of non-specific immunosuppression
- Malnutrition
- Alcohol
- Sepsis
- Trauma
Describe the usual presentation of pulmonary infection in the immunocompromised
- Pyrexia
- Lethargy
- Cough
- Dyspnoea
- Hypoxic
An immunocompromised person presents with a rapid onset pulmonary infection, is this likely to have a bacterial or viral cause?
Rapid onset is likely to be bacterial
An immunocompromised person presents with a slow onset pulmonary infection. Is this likely to have a bacterial or viral cause?
Slow onset is likely to be CMV, aspergillus or cryptococcus
Give 3 radiological indication for bronchoscopy
- Lobar colapse
- Presence of a mass
- Persistent consolidation
Give 3 non-radiological indication for bronchoscopy
- Haemoptysis
- Cough
- Wheeze
- Stridor
What are the possible complications of a bronchoscopy?
Pneumonia
Pneumothorax
A patient presents with breathlessness. On examination they have absent breath sounds and their chest produces a stony dull sound on percussion. They have a PMH of heart failure. What is the likely cause of their symptoms?
Pleural effusion