Respiratory Flashcards
What is acute bronchitis?
Acute bronchitis is a type of chest infection which is usually self-limiting in nature. It is a result of inflammation of the trachea and major bronchi
What is acute bronchitis is associated with?
oedematous large airways and the production of sputum
What is the timeline of acute bronchitis?
The disease course usually resolves before 3 weeks, however, 25% of patients will still have a cough beyond this time
What is the leading cause of acute bronchitis?
viral infection is the leading cause. Around 80% of episodes occur in autumn or winter.
What is the typical presentation of acute bronchitis?
cough: may or may not be productive
sore throat
rhinorrhoea
wheeze
The majority of patients with have a normal chest examination, however, some patients may present with:
Low-grade fever
Wheeze
How do you differentiate acute bronchitis from pneumonia?
History: Sputum, wheeze, breathlessness may be absent in acute bronchitis whereas at least one tends to be present in pneumonia.
Examination: No other focal chest signs (dullness to percussion, crepitations, bronchial breathing) in acute bronchitis other than wheeze. Moreover, systemic features (malaise, myalgia, and fever) may be absent in acute bronchitis, whereas they tend to be present in pneumonia.
What investigations do you do for acute bronchitis?
acute bronchitis is typically a clinical diagnosis
however, if CRP testing is available this may be used to guide whether antibiotic therapy is indicated
What is the treatment for acute bronchitis?
analgesia
good fluid intake
consider antibiotic therapy if patients:
are systemically very unwell
have pre-existing co-morbidities
have a CRP of 20-100mg/L (offer delayed prescription) or a CRP >100mg/L (offer antibiotics immediately)
the BNF currently recommends doxycycline first-line
doxycycline cannot be used in children or pregnant women
alternatives include amoxicillin
Define allergy disorder and its MOA
Allergy is a broad topic, with allergic disorders resulting from a variety of mechanisms. Many immediate reactions involve type 1 hypersensitivity, where an allergen is recognised by IgE antibodies, triggering cytokines to be released from mast cells (with histamine an important component of this).
What other conditions are allergies associated with?
allergic rhinitis, eczema, asthma and food allergies
Name some common allergens:
Dust mites
Foods (especially nuts, shellfish, eggs, milk and certain fruits)
Grass and tree pollens
Animal dander
Medications (e.g. penicillins, aspirin, ibuprofen)
Insect bites and stings
Name some common signs and symptoms of allergies
Itchy skin or eyes
Rashes (classically urticarial in IgE mediated hypersensitivity)
Gastrointestinal upset (diarrhoea, abdominal pain or nausea and vomiting)
Swelling of the eyes, lips, mouth or throat
Rhinorrhoea
Sneezing
Shortness of breath or wheeze
Deterioration in asthma or eczema symptoms
Conjunctivitis
What are the investigations for allergens?
First line investigations are either skin prick testing or blood testing for specific IgE levels to different food allergens
Skin prick testing involves injecting allergens (as well as positive and negative controls) into the skin then assessing these after 15 minutes to detect to which allergens a person is sensitised
Serum specific IgE testing is possible for a wide range of allergens but can take several weeks to be resulted
Some patients may be “sensitised” to specific allergens i.e. they have positive test results but no symptoms of allergy when exposed to that allergen
Because of this, testing should be targeted based on the clinical history as otherwise false positive results are common
In cases of confirmed food allergy, follow-up testing may be done to see if patients have developed tolerance to that allergen
If results of initial tests are unclear, the gold standard diagnostic test for food allergy is an oral food challenge where small quantities of the suspected allergen are administered under medical supervision and uptitrated to see if symptoms are provoked
What is the management for allergy disorder?
First line investigations are either skin prick testing or blood testing for specific IgE levels to different food allergens
Skin prick testing involves injecting allergens (as well as positive and negative controls) into the skin then assessing these after 15 minutes to detect to which allergens a person is sensitised
Serum specific IgE testing is possible for a wide range of allergens but can take several weeks to be resulted
Some patients may be “sensitised” to specific allergens i.e. they have positive test results but no symptoms of allergy when exposed to that allergen
Because of this, testing should be targeted based on the clinical history as otherwise false positive results are common
In cases of confirmed food allergy, follow-up testing may be done to see if patients have developed tolerance to that allergen
If results of initial tests are unclear, the gold standard diagnostic test for food allergy is an oral food challenge where small quantities of the suspected allergen are administered under medical supervision and uptitrated to see if symptoms are provoked
What are the complications of allergy disorder?
Malnutrition and failure to thrive in children can occur due to restrictive diets
Anaphylaxis is a life-threatening medical emergency and can lead to circulatory collapse and death if not treated promptly
Reduced quality of life can result from stress and anxiety surrounding avoiding allergens e.g. in social situations or when travelling.
What is the prognosis of allergy disorder?
Some allergies are more likely to persist than others, with many children growing out of milk, egg, soy or wheat allergies.
Others such as peanut allergy are sometimes outgrown (usually before the age of 10) but may persist into adulthood.
In what ways can asbestos lung disease present?
There are several ways asbestos exposure can manifest in the lungs, including pleural plaques, diffuse pleural thickening, pleural effusions, lung cancer and mesothelioma
What is the most common way asbestos lung presents?
Pleural plaques - these are benign and do not undergo malignant change. They, therefore don’t require any follow-up. They are the most common form of asbestos-related lung disease and generally occur after a latent period of 20-40 years.
Which conditions is pleural thickening in asbestos lung disease similar to?
empyema or haemothorax
What is asbestosis?
Asbestosis is one manifestation of asbestos lung disease and is a chronic restrictive interstitial fibrotic lung disease that typically manifests 10-20 years following exposure to asbestos fibres (often through occupational risks).
What are the signs and symptoms of asbestosis?
Symptoms:
Progressive dyspnoea manifesting over months-years
Dry cough
Weight loss
Fatigue
Signs:
Bilateral fine end-expiratory crepitations, predominantly basal
Finger clubbing
Cyanosis
What are the investigations for asbestosis?
Pulmonary function tests: the expected finding is a restrictive pattern (reduced FVC and TLC with a normal FEV1/FVC ratio) with decreased diffusion capacity.
Chest x-ray: bilateral shadowing, predominantly at the bases. Other manifestations of asbestosis exposure may be seen for example pleural plaques.
Asbestosis typically causes lower lobe fibrosis.
High resolution CT: may show honeycombing, traction bronchiectasis and parenchymal bands especially in the lower zones (all signs of fibrosis).
What are the treatments for asbestosis?
Smoking cessation: essential to reduce lung cancer risk and progression of asbestosis.
Pulmonary rehabilitation: Helps to improve lung function and quality of life.
Oxygen therapy: consider if significant hypoxaemia.
Vaccination against influenza and pneumococcal disease.
Name the malignant disease of the pleura crocidolite (blue) asbestos causes?
Mesothelioma