Respiratory Flashcards
Asthma Lung cancer Acute Bronchitis & Pneumonia (Chest infections) Sarcoidosis & TB COPD ILD (Pulmonary fibrosis) Asbestos-related lung diseases Obstructive Sleep Apnoea (OSA) Infectious mononucleosis
QoL complications - Asthma (Childhood vs adulthood development)
Childhood - growth stunt, higher risk of learning disability
Adulthood - higher risk of depression, increased sick days
Both - obesity, medication side effects, lingering cough spells
What is the definition of asthma?
chronic respiratory condition associated with airway inflammation and reversible airway obstruction
characteristic symptoms of asthma?
Wheeze, cough, chest tightness, worsening cough at night (Diurnal pattern), SOB & variable expiratory airflow limitation.
Common triggers for exacerbation of asthma?
changes in weather, drugs (NSAIDs & beta-blockers), exercise, allergens and viral respiratory infections
What is the term used for “onset of severe asthma symptoms, which can be life-threatening”
Asthma exacebation
Prevalence of asthma?
Affects 12% of UK population.
Incidence - children > adults. In childhood, boy > girls but by adulthood, girls > boys.
Occupational asthma account for 9-15% of adult-onset asthma - most common industrial lung disease in developed world
Risk factors of asthma - development or persistence?
Non-modifiable factors
- Age – childhood > adults
- Sex – development boys > girls, persistence into adulthood women > men
- Ethnicity
- Family/ Medical history – atopic diseases (incl. asthma), Respiratory disease in childhood, premature birth associated low birth weight
Modifiable risk factors
- Social conditions – poverty stricken, environment with high pollutant/ allergens/ dampness, exposure to inhaled particulates, workplace exposure – floor dust & isocyanates
- Diet – childhood obesity
- Smoking/alcohol - smoking
- Physical activity
- Medication – NSAIDs & beta-blockers
Prognosis - asthma?
Growing out - male children, early onset (< 2 yr old) without other atopic diseases (likely to be asymptomatic by 6-11)
Worse prognosis - early onset asthma in atopic children. Severe/ frequent symptoms -> more likely to persist (eg. wheeze)
Examples of atopic diseases?
Asthma, eczema, allergic rhinitis or allergic conjunctivitis
Complications - asthma?
Death, respiratory complications and impaired QoL (from suboptimal control - fatigue & underperformance)
Eg. of respiratory complications of asthma?
Irreversible airway changes, pneumonia, pulmonary collapse (atelectasis), respiratory failure, pneumothorax& status asthmaticus (repeated attacks with non-response to treatment)
Diagnosis - Asthma
Clinical judgement from…
- History - presence of hallmark symptoms
- Personal/ FHx of atopic conditions - use previous results (skin-prick, >4% blood eosinophilia, raised allergen specific igE)
- FeNO test results - confirm eosinophilic inflammation
- Spirometry, BDR, PEF readings
- Direct bronchial challenge test with histamine or methacholine (special referral)
Positive Values for FeNO test - Asthma
Steroid-naive adults >= 40 ppb
5-16 yrs >= 35 ppb
May be affected by empirical treatment with ICS
3 objective tests for airway obstruction - Asthma
Spirometry (FEV1/FVC) - all symptomatic age > 5. Bronchodilator reversibility (BDR) - Age > 5 with obstructive spirometry. Variable Peak Expiratory Flow (PEF) readings - support diagnosis of diagnostic uncertainty.
Spirometry Results Criteria - Asthma
Normal FEV1/FVC > 70%
Airflow limitation: FEV1/FVC < 70% or lower limit of normal
BDR results criteria - asthma
Adults: Improvement in FEV1 of 12% or more with increased volume of > 200ml in response to beta-2-agonist/ corticosteroids. Strong indication - improvement of 400 mL in FEV1
Children: FEV1 improvement of 12% or more
Auscultation finding - Asthma
Expiratory polyphonic wheeze
High risk occupations - Asthma?
Laboratory work, baking, animal handling, wedding and paint spraying
Prevalence - Lung cancer & mesotheliomas
Lung cancer: 3rd most common cancer in UK (behind breast & prostate)
Seen in both sex ~1:1
Mesothelioma: new diagnosis - men: female 5:1
Cigarette smoking = biggest cause. 80% of lung cancer is preventable
Histology - lung cancer
Non-small cell lung cancer (80%): adenocarcinoma (40%), squamous cell carcinoma (20%), large cell carcinoma (10%) & others
Small cell lung cancer (SCLC - 20%) - cells contain neurosecretory granules -> release neuroendocrine hormones responsible for paraneoplastic syndromes
Which lung cancer is highly associated with paraneoplastic syndromes & why?
Small cell lung cancer (SCLC - 20%) - cells contain neurosecretory granules -> release neuroendocrine hormones responsible for paraneoplastic syndromes
Presentation - Lung cancer
Systemic signs: fatigue, weight loss, appetite loss
Respiratory: SOB, haematemesis, chest pain, cough, recurrent pneumonia
Peripheral: finger clubbing, lymphadenopathy (often supraclavicular nodes)
Causes of finger clubbing
Cyanotic heart disease, Cystic fibrosis Lung cancer, lung abscess Ulcerative colitis Bronchiectasis Benign mesothelioma Infective endocarditis, idiopathic pulmonary fibrosis Neurogenic tumours GI disease - biliary cirrhosis, IBD - UC, liver cirrhosis, coeliac
Investigations - Lung cancer
First line: CXR (2ww)
Imaging: Contrast staging CAP CT (metastasis), PET-CT
Bronchoscopy with EBUS - endoscopy allowing detailed assessment of tumour in bronchi and Us-guided biopsy
EGFR-TK mutation testing
Histological diagnosis - bronchoscopy/ percutaneous biopsy
CXR findings - Lung cancer
Airway: hilar enlargement
Breathing: peripheral opacity - visible lesion in lung field, pleural effusion, collapse
CXR - ABCD approach
Airway: trachea, carina, bronchi and hilar structures
Breathing: lung and pleura
Cardiac: heart size and borders
Diaphragm: including assessment of costophrenic angles
Everything else: mediastinal contours, bones, soft tissues, bones, valves, pacemakers and review areas
Prognosis - lung cancer and mesothelioma
5 year survival
Non-small cell lung cancer has better prognosis than small cell lung cancer
Treatment options - Non-small cell lung cancer
First line: Surgery - lobectomy (first line), segmentectomy or wedge resection
Radiotherapy (Stereotactic ablative body radiotherapy (SABR): curative if early enough
Chemotherapy: adjuvant chemo or as palliative treatment to improve survival and quality of life in later stages
Systemic treatments: Oncogene directed (metastatic NSCLC with mutation), immunotherapy (metastatic NSCLC with no mutation ad PDL1 > 50%), cytotoxic chemotherapy (Metastatic, nil mutation, PDL1 <50%)
Endobronchial treatment with stents and debulking - palliative treatment to relieve bronchial obstruction caused by lung cancer
Treatment - Small cell lung cancer (SCLC)
Chemotherapy and radiotherapy
Endobronchial treatment with stents and debulking - palliative treatment to relieve bronchial obstruction caused by lung cancer
Extrapulmonary manifestations - non-small cell lung cancer
Recurrent laryngeal nerve palsy: present with hoarse voice. Cause - cancer pressing on/ affecting recurrent laryngeal nerve as it passes though mediastinum
Phrenic nerve palsy due to nerve compression causes diaphragm weakness and presents as shortness of breath.
Superior vena cava obstruction is a complication of lung cancer. It is caused by direct compression of the tumour on the superior vena cava. It presents with facial swelling, difficulty breathing and distended veins in the neck and upper chest. “Pemberton’s sign” is where raising the hands over the head causes facial congestion and cyanosis. This is a medical emergency.
Horner’s syndrome is a triad of partial ptosis, anhidrosis and miosis. It is caused by a Pancoast’s tumour (tumour in the pulmonary apex) pressing on the sympathetic ganglion
What is the sign associated with superior vena cava obstruction which is a medical emergency
Pemberton’s sign - raising hands over head leads to cyanosis and facial congestion
Paraneoplastic syndromes assoc. with small cell lung cancer
SIADH: caused by ectopic ADH secretion by a small cell lung cancer and presents with hyponatraemia.
Cushing’s syndrome can be caused by ectopic ACTH secretion by a small cell lung cancer.
Hypercalcaemia caused by ectopic parathyroid hormone from a squamous cell carcinoma.
Limbic encephalitis. This is a paraneoplastic syndrome where the small cell lung cancer causes the immune system to make antibodies to tissues in the brain, specifically the limbic system, causing inflammation in these areas. This causes symptoms such as short term memory impairment, hallucinations, confusion and seizures. It is associated with anti-Hu antibodies.
Lambert-Eaton myasthenic syndrome. Immune system attacks neuromuscular junctions (voltage-gated calcium channels sited on the presynaptic terminals in motor neurones.)
What are the main neuroendocrine secretions of small-cell lung cancer
Hormones: ADH, ACTH, PTH
Antibodies: Anti-Hu (limbic encephalitis)
Lambert-Eaton Myasthenic Syndrome - Cause and Presentation
Antibodies secreted against SCLC also targets and affect voltage-gated calcium channels on presynaptic terminals in motor neurones in neuromuscular junction.
Presentation: weakness (esp. proximal muscles), intraocular muscles -> diplopia, levator muscles -> ptosis and pharyngeal muscles -> slurred speech and dysphagia.
Other symptoms: dry mouth, blurred vision, impotence and dizziness from automatic dysfunction.
Reduced tendon reflexes. A notable finding - reflex become temporarily normal for a short period following a period of strong muscle contraction. For example, the patient can maximally contract the quadriceps muscle for a period, then have their reflexes tested immediately afterwards, and display an improvement in the response. This is called post-tetanic potentiation.
In older smokers with symptoms of Lambert-Eaton syndrome consider small cell lung cancer.
What is mesothelioma?
Lung malignancy affecting the mesothelial cells/ mesothelium (of the pleura)
It is strongly linked to asbestos inhalation. There is a huge latent period between exposure to asbestos and the development of mesothelioma of up to 45 years. The prognosis is very poor. Chemotherapy can improve survival but it is essentially palliative.
Mesothelioma: Possible sites
Lung pleura (pleural), pericardium (pericardial), lining of the abdomen (peritoneal) & sac surrounding testes (testicular)
Mesothelioma: Presentation
Think about possible sites affected
Cancer red flags - fatigue, weight loss, anorexia, fever (large portion of energy depleted), night sweats
Respiratory: Chest pain (pleural effusion), Cough, dyspnoea, hemoptysis
Abdominal: abdominal mass, jaundice, ascites, vomiting and constipation (umbilical hernia)
Mesothelioma: Diagnosis & Histology (3 main malignant types)
CXR with biopsy confirmation
Epitheliod mesothelioma - uniform, sharply defined and square to tubular in configuration. They feature prominent nuclei and divide quickly but tend to stick together. This means it takes longer for them to spread throughout the body. The epithelial cell type accounts for more than 50% of all mesothelioma cases and up to 70% of cases.
Sarcomatous - Spindle-shaped sarcomatoid cells typically lack defining structure and have an irregular configuration. They spread more quickly than epithelial cells because they don’t tend to stick together as they grow. This rare cell type characterizes 10% to 20% of cases.
Biphasic - Malignant mesothelioma is considered biphasic when it contains epithelial and sarcomatoid cells. Each cell type must account for at least 10% of the tumor mass to receive a biphasic diagnosis. The biphasic (mixed) cell type accounts for 20% to 30% of mesothelioma cases.
Mesothelioma: Prognosis of 3 main malignant subtypes
Epitheliod mesothelioma: Slower rate of metastasis. Most responsive to treatment -> better prognosis
Sarcomatous mesothelioma: poor respose to treatment. Most negative prognosis
Biphasic: prognosis dependant on epithelial cells: sarcomatoid cells
Mesothelioma: Treatment
CHEMOTHERAPY (pemetrexed, cisplatin, carboplatin)
SURGERY (pleurectomy/ decortication, extrapleural pneumonectomy or pericardectomy) with RADIATION and/or CHEMO
Advances diffused mesothelioma: Chemotherapy + radiotherapy
Risk factors - Lung cancer
Non-modifiable risk factors
- Age: peak 75-90
- Sex: male>female
- Personal/ FHx: chronic lung conditions (COPD), immunodeficiency & genetic loci
Modifiable risk factors
- Social: low socioeconomic status, passive smoking
- Smoking/ alcohol - duration, intensity and cessation onset
- Exposures: occupational - asbestos & radon, indoor cooking fumes
- Occupation: plumbers, ship-builders, carriage workers, carpenters
Common tumour sites for different NSCLC pathophysiology
Adenocarcinoma: originated from mucus-producing glandular tissue, more peripherally located (deep inhalation of particulates)
Squamous cell carcinoma: originated form bronchial epithelium; centrally located
Large cell cancer: heterogenous group, undifferentiated
Lung cancer - oncogenes mutation important for directed treatments
EGFR: 15-30% of adenocarcinoma, female, Asian ethnicity, non-smokers
ALK: 2-7% of NSCLC, younger patients, non-smokers
ROS1: 1-2% of NSCLC, younger patients, non-smokers
BRAF: 1-3% of NSCLC, smokers
Presentations of asso. paraneoplastic syndrome (+ condition name) for SCLC
Hyponatremia (SIADH), Cushing’s, hypercalcaemia (PTH)
Limbic encephalitis: ST memory impairment, hallucinations, confusion and seizures
Focal weakness (Lambert-Eaton myasthenic syndrome)
Asthma: Management goal & how achieve Asthma
- Reduce airway eosinophilic inflammation: ICS & Leukotriene receptor antagonist (reduce T2 inflammation)
- Acute symptomatic relief (smooth muscle relaxation): Beta-2-agonist (SABA) & Anticholinergic therapies
- Severe asthma: steroid sparring therapies - Biologic targeted to IgE (Anti-IgE antibody) or biologics targeted to airway eosinophils (Anti-IL-5 antibodies or Anti-IL5 receptor antibody) In5
Treatment: Asthma step-up plan
- PRN reliever (SABA)
- Add regular preventer (low dose ICS)
- Initial add-on therapy: add inhaled LABA or LTRA
- Additional controller therapies: ?increasing ICS to medium dose OR ?Adding LTRA. If no LABA response, consider stopping LABA
- Specialist therapies: refer
Why is respiratory viral infections a risk factor to asthma exacebations and not bacteria?
Prolonged infection leads to decreased IFN-a,b,d
Decreased IFN -> decreased viral replication inhibition -> increased viral replication -> prolonged illness and asthma severity
Asthma treatment - Anti-IgE antibody example
Omalizumab - for severe eosinophilic asthma (blood Eos =>300 cells/mcl in last 12 months)
Role of skin prick aeroallergen test for asthma diagnosis
Not diagnostic test for asthma.
Done after official diagnosis to identify triggers
Possible reasons for uncontrolled asthma that should be considered before stepping up treatment
Patient factors: lack of adherence, suboptimal inhaler technique, smoking (passive / active), psychological factors
Doctor factors: alternative diagnosis
Environmental or seasonal factors
Definition - Pneumonia
Infection of the lung tissue. It causes inflammation of the lung tissue and sputum filling the airways and alveoli
X-ray finding - Pneumonia
Lung consolidation
Pneumonia - 3 main classifications
Community Acquired Pneumonia - developed outside hospital
Hospital Acquired Pneumonia - developed > 48hr after admission
Aspiration Pneumonia
Presentation - Pneumonia
Systemic - fatigue, febrile, delirium, SEPSIS
Respiratory: SOB, productive cough w/ sputum, Haemoptysis, pleuritic chest pain
Clinical signs (+ chest examination) - Pneumonia
Sepsis: tachypnoea, tachycardia, hypotension, hypoxia
Fever, Confusion
Sounds: Bronchial breath sounds, Focal coarse crackles, Dullness to percussion
Explain characteristics of 3 main chest exam. results for Pneumonia
Bronchial Breath sounds: harsh breath sounds equally loud on inspiration and expiration. Caused by consolidation of lung tissue in airway
Focal coarse crackles: air passing through sputum
Dullness to percussion: lung tissue collapse and/or consolidation
Pneumonia - Severity Scoring system. What is the difference between CAP and HAP
CAP: CRB-65 and HAP: CURB-65
CURB-65 does not count urea
The CURB 65 score predicts mortality (score 1 = under 5%, score 3 = 15%, score 4/5 = over 25%). The scoring system is there to help guide whether to admit the patient to hospita
What is CURB-65 criteria consist of?
Confusion (new disorientation in person, place or time),
Urea > 7
Respiratory rate >= 30
Blood pressure <90 systolic or <=60 diastolic
65 - age >=65
The CURB 65 score predicts mortality (score 1 = under 5%, score 3 = 15%, score 4/5 = over 25%). The scoring system is there to help guide whether to admit the patient to hospital:
Score 0/1: Consider treatment at home
Score ≥ 2: Consider hospital admission
Score ≥ 3: Consider intensive care assessment
Pneumonia - Common causes and other causes/ associations
Common: Streptococcus pneumonia (50%) & haemophilias influenzae (20%)
Other causes: Moraxella catarrhalis - in immunocompromised patients/ with chronic pulmonary disease, Pseudomonas aeruginosa - CF/ bronchiectasis patients, Staphylococcus aureus - CF patient’s
Common diseases (via direct tissue invasion) caused by Staphylococcus aureus
Skin infections, Pneumonia, Endocarditis, Osteomyelitis, Infectious (septic) arthritis
Definition - Atypical Pneumonia
The definition of atypical pneumonia is pneumonia caused by an organism that cannot be cultured in the normal way or detected using a gram stain.
They don’t respond to penicillins and can be treated with macrolides (e.g. clarithomycin), fluoroquinolones (e.g. levofloxacin) or tetracyclines (e.g. doxycycline)
Treatment for atypical pneumonia
They don’t respond to penicillins.
Can be treated with macrolides (e.g. clarithomycin, erythromycin), fluoroquinolones (e.g. levofloxacin) or tetracyclines (e.g. doxycycline)
Causes of atypical pneumonia
Legions of psitacci MCQs
Legionella pneumophilia (Legionnaires’ disease): typically by infected water supplies or air conditioning units. Can cause SIADH -> hyponatraemia (low. The typical exam patient has recently had a cheap hotel holiday and presents with hyponatraemia.
Mycoplasma pneumoniae.: This causes a milder pneumonia and can cause a rash called erythema multiforme characterised by varying sized “target lesions” formed by pink rings with pale centres. It can also cause neurological symptoms in young patient in the exams.
Chlamydia psittaci: This is typically contracted from contact with infected birds. The MCQ patient is a from parrot owner.
Chlamydophilia pneumoniae: The presentation might be a school aged child with a mild to moderate chronic pneumonia and wheeze. Be cautious though as this presentation is very common without chlamydophilia pneumoniae infection.
Coxiella burnetii AKA “Q fever”. This is linked to exposure to animals and their bodily fluids. The MCQ patient is a farmer with a flu like illness.
What is the rash associated with atypical pneumonia? What is the bacteria?
Erythema Multiforme - target lesions
Mycoplasma pneumoniae