Lung Pathology Flashcards
WHAT IS COPD?
Collection of lung diseases that cause IRREVERSIBLE obstruction to airflow out of the lungs.
Umbrella term for two diseases chronic bronchitis and emphysema
What are the causes of COPD?
Smoking
A1AT
IV drug use
Industrial exposure to chemicals
WHAT IS CHRONIC BRONCHITIS?
https://www.youtube.com/watch?v=Y29bTzKK_P8
Bronchial tubes inflammation
IRREVERSIBLE
What is chronic bronchitis defined as?
Cough, sputum production on most days for 3 months of 2 successive yrs
What does smoking cause?
What does this cause?
In chronic bronchitis
Hypertrophy and hyperplasia of the mucinus glands (bornchi)
Hypertrophy and hyperplasia of goblet cells (bronchioles)
Increase in mucus
Cilia also become short and less motile
Harder to move mucus
Air trapping
How can pulmonary hypertension happen in chronic bronchitis?
Decreased gas exchange causign vasocontriction
Large proportion
Increases pulminary vascular resistance
Develops pulmonary hypertension
Right side of heart enlarges
Cor pulmonale
How can a person become cyanosed in chronic bronchitis?
CO2 trapped in alveoli takes up more space
O2 unable to fill alveoli
Less goes into the blood
More CO2 in alveoli means less CO2 can come out the blood
More CO2 in blood less O2
What is the reid index?
Size of the mucinus glands relative to the rest of the layers
Who does chronic bronchitis affect?
Affects middle aged heavy smokers
Some following pollution chronically
Recurrent low grade bronchial infections
What are the symptoms of chronic bronchitis?
Dyspnea
Wheeze
Crackles
Cough
Production of mucus (sputum)
What are the signs of chronic bronchitis?
Hypoxemia
Hypercapnia
These cause cyanosis
Pulmonary hypertension
Result of low O2
Causing cor pulmonale
Tachypnoea
Use of accessory muscles
Hyperinflation
What are the differential diagnosis for chonic bronchitis?
Alpha1-Antitrypsin Deficiency
Asthma
Bronchiectasis
Chronic Obstructive Pulmonary Disease (COPD)
Chronic Sinusitis
Gastroesophageal Reflux Disease
Influenza
What are the investigations for chronic bronchitis?
Spirometry
Chest X-ray
Rule out other lung conditions, such as pneumonia.
ECG
Right venticle and atria enlargment (cor pulmonale)
Sputum (bacteria).
ABG: PaO2 decrease ± hypercapnia
What are the non-pharmocological management options for chronic bronchitis?
Stop smoking
Physical activity
Vaccinations
Flu
Pneumococcal
Pertussis
What is the pharmocological management options for chronic bronchitis?
What is mMRC and CAT in COPD?
The modified Medical Research Council (mMRC) Questionnaire is widely used for assessing the severity of breathlessness in patients with COPD.
The COPD Assessment Test (CAT) is a questionnaire for people with Chronic Obstructive Pulmonary Disease (COPD).
WHAT IS EMPHYSEMA?
https://www.youtube.com/watch?v=TEuSV_7gWA8
Enlargement of alveolar airspaces with destruction of elastin in walls.
What are the causes of emphysema?
- Cigarette smoking. (MAINLY)
- Alpha-1-antitrypsin deficiency
- Coal dust exposure
- Cadmium toxicity
What happens when the alveoli becomes irritated by smoke?
What does this do?
What happens when exhaling?
Triggers an inflammatory response, immune cells come in
Releasing inflammatory mediators
(Proteases, Collangenases)
Breaks down the collagen and elastin in the alveoli wall
Bernoulli principle
Exhalation of air has a lower pressure and pulls the airway inwards, ormal airways can withstand this
Emphysema airways have less elastin and collagen therefore collapse
Leads to air trapping
What happens when air comes into emphysema lungs?
Lungs are more compliant
Lungs overinflate
What happens in alpha-1 antitrypsin deficiency?
- Macrophages produce proteases
- Helps clear debris
- Can damage tissue
- Alpha-1 antitrypsin is a protease inhibitor
- Protects against damage
- Deficiency means proteases can damage lungs
What are the oxygen and carbon dioxide levels in emphysema?
‘pure’ emphysema appears with reduced PaCO2 and normal PaO2 at rest due to overventillation (‘pink puffers’)
What are the symptoms of emphysema?
Dyspnea - shortness of breath
Exhaling through pursed lips to keep lungs inflated
Cough - sputum
Weight loss due to metabolic demands
1/3 of lung capacity is destroyed before symptoms
What are the signs of emphysema?
Barrel chest - overinflated chest on x-ray
Flattened diaphragm
Pulmonary hypertension
Right heart failure
What are the differential diagnosis of emphysema?
Bronchiectasis
Bronchitis
Lymphangioleiomyomatosis
What are the investigations for emphysema?
Pulmonary/Lung Function tests
Spirometry is the best test to detect airflow limitation and obstruction.
Blood tests
Hb level increase secondary polycythaemia.
Chest x-ray
This helps to show hyperexpansion of the lungs.
ECG or Echocardiogram
Right heart failure (a complication of emphysema and COPD).
Blood gases
Normal, later stages of disease, low oxygen and high carbon dioxide levels.
High resolution CT
Best test for detecting emphysema and bullae (big dilated air spaces).
What are the non-pharmocological management options for emphysema?
Stop smoking
Physical activity
Vaccinations
Flu
Pneumococcal
Pertussis
What is the pharmocological management options for emphysema?
What are the complications of COPD?
Pneumothorax
Cor pulmoale
Acute exaccerbations
Infection
WHAT IS AN EXACERBATION OF COPD DEFINED AS?
An exacerbation can be defined as a sustained worsening of the patient’s symptoms from his or her usual stable state that is beyond normal day-to-day variations, is acute in onset and requires additional therapy
What are the most likely causative organism in an exacerbation of COPD?
S. pneumoniae, H. influenzae and Moraxella cartarrhalis
What are the clinical features of an exacerbation of COPD?
worsening of previous stable condition
increased wheeze
increased dyspnoea
increased sputum volume
increased sputum purulence
chest tightness
fluid retention
reduced exercise tolerance
increased fatigue
What are the investigations for an exacerbation of COPD?
Chest X-ray
Arterial Blood Gas
Sputum Sample
What is the treatment for an exacerbation of COPD?
Increase bronchodilator use - consider nebs
Antibitoics
Amoxicillin
Steroids
Prednisolone
What is given for prophylaxis against exaccerbations in COPD?
Azithromycin 250mg 3 times a week
WHAT IS BRONCHIECTASIS?
https://www.youtube.com/watch?v=rTcVPHszU5E
Irreversible dilation of the bronchioles
What are the causes of bronchiectasis?
**_Congenital_** Cystic fibrosis (CF);
Post-infection
TB
HIV
**_Other_** Bronchial obstruction (tumour, foreign body)
What is the pathology of bronchiectasis?
Infection and imparied drainage
Activates neutrophilic proteases and cytokines causing inflammation
Increaed mucus and increased stagnent bacteria
Cycle starts again
What are the signs and symptoms of bronchiectasis?
Chronic cough - foul smelling sputum
Flecked with blood sometimes.
Finger clubbing
Coarse inspiratory crepitations.
Wheeze
What are the differential diagnosis for bronchectasis?
Alpha1-Antitrypsin Deficiency
Aspiration Pneumonitis and Pneumonia
Asthma
Bronchitis
Chronic Obstructive Pulmonary Disease (COPD)
Cystic Fibrosis
Emphysema
Gastroesophageal Reflux Disease
What are the tests for bronchiectasis?
Sputum culture
Chest X-Ray
Cystic shadows, thickened bronchial walls
HRCT chest
To assess extent and distribution of disease.
Spirometry
Obstructive.
What is the management for bronchiectasis?
Stop smoking
Airway clearance exercises
Bronchodilators
Corticosteroids
Antibiotics - if infective cause
Amoxicillin
What are the complications with bronchiectasis?
Pneumonia
Emphysema
Septicaemia
Amyloid formation.
WHAT IS ALPHA-1 ANTITRYPSIN DEFICIENCY?
A deficiency in alpha-1 antitrypsin
What does alpha-1 antitryspin do?
What is the gene that codes for it?
What chromosome is it on?
Inactivates elastase (a protease)
SERPINA1
Long arm of chromosome 14
When would you favour alpha 1-antitryspin deficiency as a dignosis?
Never smoked
Young
What are the symptoms of alpha-1 antitrypsin deficiency?
Shortness of breath
Wheezing
Mucus production
Chronic cough
Cirrhosis
Inability to make coagulation factors
Build up of toxins
What investigations are done for alpha-1 antitrypsin deficiency?
Assaying protease inhibitor activity
Typing proteins with isoelectric focusing
Bloods
A1AT low
Biopsy
Liver - Periodic-acid shiff stain
What is the treatment of alpha-1 antitrypsin deficiency?
Augmentation therapy
IV infusion of normal protein
Slow of halts progression
Inhlaers
Oxygen
Liver transplant
WHAT ARE INTERSTITIAL LUNG DISEASES?
Disease of the alveoli primarily
Scarring
Fibrosis
What are some causes of interstitial lung disease?
Congenital
Neurofibromatosis
Tuberous sclerosis
Chemical or dust inhalation
Organic dusts e.g. moulds, avian proteins
Mineral dusts e.g. silica, coal dust, asbestos
Unknown causes:
Idiopathic haemosiderosis
Sarcoidosis
What are the symptoms of interstitial lung diseases?
Dry cough
Digital clubing
Diffuse inspiratory crackles
Dysponea
What can acute interstitial lung diseases cause?
Acute respiratory distress syndrome
WHAT ARE SOME CAUSES OF ACUTE RESPIRATORY DISTRESS?
Shock
Trauma
Infections
Gas inhalation
Narcotic abuse
What are the symptoms of acute respiratory distress syndrome?
Tachypnoea
Dyspnoea
Pulmonary oedema
WHAT IS PNEUMOCONIOSIS?
Lung disease caused by inhaled dust Organic or inorganic dust (mineral)
What happens in coal workers’ pneumoconiosis?
Coal is ingested by alveolar macrophages (dust cells)
They aggregate around bronchioles
The consequences vary from trivial to lethal.
WHAT IS RHEUMATOID ARTHRITIS INTERSTITIAL LUNG DISEASE?
Rheumatoid arthritis interstitial lung disease (RA-ILD) is increasingly recognised and is clinically significant in up to 5% of patients with RA
What are the investigations for rheumaotid arthritis interstitial lung disease?
- Pulmonary function testing
- High resolution CT
What is the treatment for rheumatoid arthritis interstitial lung disease?
High-dose corticosteroids
Prednisolone
Immunosuppresants
Azathioprine
What is Caplan’s syndrome?
The association between rheumatoid arthritis, pneumoconiosis, and pulmonary rheumatoid nodules.
How do you treat coal workers pneumoconiosis?
Avoid exposure to coal dust
Treat co-existing chronic bronchitis
WHAT IS ASBESTOSIS?
Pneumoconiosis caused by inhalation of asbestos fibres, classically causing a chronic, diffuse, interstitial fibrosis of the lun
What is asbestosis caused by?
Inhaltion of asbestos.
What are the features of asbestosis?
Similar to other fibrotic lung diseases with progressive dyspnoea, clubbing, and fine end-inspiratory crackles.
Also causes pleural plaques, increased risk of bronchial adenocarcinoma and mesothelioma.
What are the investigations for asbestosis?
Chest X-ray
Diffuse bilateral shadowing, honeycomb lung. There may be pleural plaques which are an indicator of previous exposure to asbestos
Lung function tests
Restrictive
What is the management of asbestosis?
Symptomatic.
Patients are often eligible for compensation through the UK Industrial Injuries Act.
WHAT IS EXTRINSIC ALLERGIC ALVEOLITIS?
https://www.youtube.com/watch?v=PIuj6XiMlps
Inflammation of the alveoli due to an extrinsic allergen of known type
What are two types of extrinsic allergic alveolitis?
Bird fancier’s lung
Avian proteins in droppings
Antigens
Farmer’s lung
Caused by fungus (poorly stored / mouldy hay)
What is the pathology of EAA?
What type of sensitivity is it?
Allergens comes in
Irritates alveoli and activates neutrophils
Releases inflammatory cytokines
Cascade leads to B cell antibody prodction
Complexes form
TYPE 3
What are the two types of EEA?
Acute (few hours after only inflammation)
Chronic (fibrosis)
What is seen in chronic that is not seen in acute EAA?
Granulomas
Non-caseating
Macrophages fuse with eachother making granulomas
What are the symptoms of extrinsic allergic alveolitis?
Acute
Fever
Rigors
Myalgia
Dyspnoea
Crackles (no wheeze).
Chronic
Increasing dyspnoea
Weight decrease
Exertional dyspnoea
Type I respiratory failure
Cor pulmonale.
What are the tests for extrinsic allergic alveolitis?
CXR
Upper-zone mottling/consolidation
Honeycombing sometimes
Blood
FBC (neutrophilia); ESR increase; ABGS; positive serum precipitins (indicate exposure only).
Lung function tests
Restrictive defect; reduced gas transfer during acute attacks.