Respiratory Disease Summaries Flashcards
Asthma
chronic inflammatory condition of the large and small airways that causes episodic exacerbations of bronchoconstriction
Asthma signs/symptoms
- Diurnal variability. Typically, worse at night and early morning
- Dry cough (Non-productive) with wheeze and shortness of breath
- A history of other atopic conditions such as eczema, hayfever and food allergies
- Associated atopy ↑IgE ( rhinitis , conjunctivitis, eczema)
Asthma management
- SABA
- Inhaled Corticosteroid e.g. beclometason
- LABA e.g. salmeterol
- Oral leukotriene antagonist, oral B2 agonist, oral theophylline or inhaled LAMA
- Titrate inhaled steroid
- Add in oral steroids
Omalizumab
inhibits the binding to the high-affinity IgE receptor which inhibits TH2 response and associated mediator release from basophils/mast cells
ABGs asthma
Initially patients will have a respiratory alkalosis as tachypnoea causes a drop in CO2.
A normal pCO2 or hypoxia is a concerning sign as it means they are tiring and indicates life threatening asthma.
A respiratory acidosis due to high CO2 is a very bad sign in asthma.
Grading PEFR
Moderate: 50-75%
Severe: 33-50%
Life-threating: under 33%
Acute asthma management
- O - oxygen - high flow 100%
- S - salbutamol -Nebulised
- H - hydrocortisone - given IV
- I - ipratropium Bromide IV
- T - theophylline
- M - magnesium Sulphate
- AN – anaesthetist
COPD
• Chronic obstructive pulmonary disease (COPD) is a non-reversible, long term deterioration in air flow through the lungs caused by damage to lung tissue.
Chronic bronchitis and emphysema
COPD investigations
Spirometry: >0.75% and no reversibility to salbutamol <15%
- Full blood count for polycythaemia or anaemia. Polycythaemia (raised haemoglobin) is a response to chronic hypoxia.
- Baseline BMI to assess weight loss (e.g. cancer or severe COPD) or weight gain (e.g. steroids).
- Sputum culture to assess for chronic infections such as pseudomonas.
- ECG and echocardiogram to assess heart function.
- CT thorax for alternative diagnoses such as fibrosis, cancer or bronchiectasis.
- Serum alpha-1 antitrypsin to look for alpha-1 antitrypsin deficiency
COPD management
- beta-2 agonists
- No asthmatic or steroid responsive features: combined long-acting beta agonist (LABA) plus a long acting muscarinic antagonist
Or
Asthmatic or steroid responsive features: combined long acting beta agonist (LABA) plus an inhaled corticosteroid (ICS).
- LABA, LAMA and ICS e..g trimbo
Exacerbation of COPD
Acute worsening of symptoms such as cough, shortness of breath, sputum production and wheeze.
It is usually triggered by a viral or bacterial infection.
o Haemophilus influenzae & Moraxella catarrhalis, Streptococcus pneumoniae, Gram-negatives & others
COPD exacerbation Ix
Chest x-ray to look for pneumonia or other pathology
ECG to look for arrhythmia or evidence of heart strain (heart failure)
FBC to look for infection (raised white cells)
U&E to check electrolytes which can be affected by infection and medications
Sputum culture if significant infection is present
Blood cultures if septic
management of COPD exacerbation
o Nebulised bronchodilators (e.g. salbutamol 5mg/4h and ipratropium 500mcg/6h)
o 24-28% Oxygen titrated against PaO2/PaCO2
o Antibiotics if evidence of infection e.g. amoxicillin or doxycycline
o Steroids (e.g. 200mg hydrocortisone or 30-40mg oral prednisolone)
idiopathic pulmonary fibrosis causes
secondary: o rheumatoid, SLE, systemic sclerosis, asbestos, alpha-1-antitripsin deficiency
,drugs - amiodarone, bleomycin, penicillamine, nitrofurantoin, methotrexate, cyclophosphamide
IPF Investigations
- Restrictive defect on PFT’s - reduced FEV1 and FVC with normal or raised FEV1/FVC ratio, reduced lung volumes, low gas transfer
- CxR - bilateral infiltrates;
- CT scan - reticulonodular fibrotic shadowing, worse at the lung bases, and periphery.
- High resolution CT scan of the thorax – ground glass appearance
IPF management
steroids and immunosuppressants to slow disease down
Pirfenidone: anti-fibrotic and anti-inflammatory
Nintedanib: tyrosine kinase monoclonal antibody
oxygen
lung transplant
Hypersensitivity Pneumonitis (AKA Extrinsic Allergic Alveolitis)
type III hypersensitivity reaction to an environmental allergen . Causes parenchymal inflammation and destruction
allergens: o Bird-fanciers lung is a reaction to bird droppings (avian proteins)
o Farmers lung is a reaction to mouldy spores in hay (thermophilic bacteria)
o Mushroom workers’ lung is a reaction to specific mushroom antigens (fungi)
o Malt workers lung is a reaction to mould on barley
Hypersensitivity Pneumonitis (AKA Extrinsic Allergic Alveolitis) signs/symptoms
acute: several hours after acute exposure - cough episodic breathless, fever and myalgia, crackles (no wheeze)
chronic: progressive breathless and cough, may be crackles
Hypersensitivity Pneumonitis (AKA Extrinsic Allergic Alveolitis) investigations
- CxR pulmonary fibrosis - most commonly in the upper zones due to better ventilation of the upper lobes then the lower
- PFTs: restrictive defect (low FEV1 & FVC, high or normal ratio, low gas transfer - TLCO)
- Lung biopsy if in doubt
hypersensitivity pneumonitis management
o2, steroids and antigen avoidance
Cryptogenic Organising Pneumonia
focal area of inflammation of the lung tissue. This can be idiopathic or triggered by infection, inflammatory disorders, medications, radiation or environmental toxins or allergens.
Cryptogenic Organising Pneumonia Mx
steroids
Sarcoidosis
multisystem granulomatous inflammatory condition (type IV hypersensitivity). • Granulomas are nodules of inflammation full of macrophages
sarcoidosis classic triad
- Erythema nodosum
- Bilateral hilar lymphadenopathy
- Polyarthralgia (joint pain in multiple joints)
sarcoidosis diagnosis
Bloods:
o Raised serum ACE (screening)
o Hypercalcaemia
o Raised CRP
o Raised immunoglobulins
o U&Es, LFTS
o Urine dipstick or urine albumin-creatinine ratio to look for proteinuria indicating nephritis
o Ophthalmology
o ECG and echocardiogram for heart involvement
o Ultrasound abdomen for liver and kidney involvement
Imaging
o Chest x-ray shows hilar lymphadenopathy
o High resolution CT thorax shows hilar lymphadenopathy and pulmonary nodules
o MRI can show CNS involvement
o PET scan can show active inflammation in affected areas
• Biopsy: Non-caseating granulomas with epithelioid cells
sarcoidosis management
acute: nothing or oral steroids
chronic: oral steroids, immunosuppression e.g. azathioprine, methotrexate, anti-TNF therapy, lung transplant
asbestosis
lung fibrosis related to the inhalation of asbestos.
o Benign pleural plaques – asymptomatic: usually develop future complications
o Acute asbestos pleuritis - fever, pain, bloody pleural effusion
o Pleural Effusion and Diffuse pleural thickening - restrictive impairment
adenocarcinoma and malignant mesothelioma
Coal workers pneumoconiosis
occupational disease (type of pneumoconiosis) caused by exposure to coal dust free of silica (washed coal).
types of coal workers pneuumoconiosis
Simple pneumoconiosis
o chest X-ray abnormality only
o no impairment of lung function - often associated with chronic obstructive pulmonary disease
Complicated pneumoconiosis
o progressive massive fibrosis - restrictive pattern with breathlessness
Lung cancer types
• Non-small cell lung cancer:
o Squamous cell carcinoma (35%): pink keratin
o Adenocarcinoma (25%): glands mucin – most common with non-smokers
o large cell carcinoma (10%): undifferentiated
Small Cell Lung Cancer (SCLC) (20%)
signs/symptoms of lung cancer
SOB Cough >3 weeks Haemoptysis hoarse voice finger clubbing stridor anaemia unexplained weight loss recurrent pneumonia
lung cancer investigations
FBC, Coagulation screen, Na, K, Ca, Alk Phos
FEV
CXR
CT Scan: lung to adrenal glands
PET-CT scans
management non-small cell lung cancer
surgery: pneumonectomy, lobectomy and segmentectomy
radiotherapy
chemotherapy: adjuvant
small cell lung cancer management
chemotherapy and radiotherapy
mesothelioma
• Lung malignancy affecting the mesothelial cells of the pleura or very occasionally of the lining of the abdominal cavity.
mesothelioma investigations
Imaging: pleural nodularity, pleural thickening, local invasion and lung entrapment
• Aspiration: Low cytological yield and protein > 30 g/L (exudate)
• Investigate if cancer in pleural space is malignant or not
Mesothelioma management
• Pleurodesis: adhere your lung to your chest wall to prevent fluid or air from continually building up around your lungs
o TALC sclerosing agent: minor pleuritic pain and fever
o Long term pleural catheters: malignant effusion
o TS spend longer in hospital and need more rescue procedures
o IPC have more adverse event
• Radiotherapy
• Surgery
• Chemotherapy can improve survival but it is essentially palliative.
Pleural effusion
abnormal collection of fluid in the pleural cavity
Classification of pleural effusion
Exudative: high protein count (>3g/dL)
o Related to inflammation: protein leaks out of the tissues into pleural space (moving out) e.g. Malignancy, pneumonia, RA, trauma and TB
Transudative: lower protein count (<3g/dL).
o Fluid moving across into pleural space e.g. Congestive cardiac failure, hypoalbuminaemia, hypothyroidism, Meig’ syndrome (right sided pleural effusion with ovarian malignancy)
Lights criteria
exudative if
1. fluid protein: serum protein >0.5
- fluid LDH: serum LDH >0.6
- Fluid LDH > 2/3rds normal upper limit of serum LDH
- Fluid cholesterol level is over 45 mg/dl
pleural effusion Iv
CXR: blunting of costophrenic angle and meniscus in larger effusions
Aspiration or chest drain
Pleural effusion management
small effusions can resolve and treat underling cause e.g. heart failure
Larger: aspiration or drainage and chest drain
Empyema
infected pleural effusion
Empyema organisms
Aerobic organisms most frequently
Gram Positive: Strep Milleri and Staph Aureus
Gram Negatives: E-Coli, Pseudomonas, Haemophilus Influenzae and Kelbsiellae
Complicated parapneumonic effusion
pH < 7.2, LDH > 1000, Glucose < 2.2: Using up glucose
empyema: frank pus
empyema signs/symptoms
improving pneumonia but on going or new fever
pleuritic chest pain
swinging fever
Empyema Iv
CXR: persisting effusion - D sign USS CT CRP rise despite antibiotics albumin dropping: low 30s and 20s
Empyema management
chest drain, IV amox and metroidazole and then oral antibiotics usually 5 weeks (co-amoxiclav)
Primary vs secondary pneumothorax
Primary spontaneous (normal lungs) Pneumothorax may be asymptomatic even if moderately sized
Secondary Spontaneous (infection, asthma or copd): Pneumothorax usually symptomatic even if small
Pneumothorax inv
Erect CXR:
- small <2cm of air
- large >2cm of air
CT thorax
Primary Pneumothorax management
no SOB and <2cm - no treatment
if SOB and >2cm of air - aspiration and chest drain
Secondary Pneumothorax management
• Unstable patients or bilateral or secondary pneumothoraces generally require a chest drain and admission for 24 hours
o In a small pneumothorax, <1cm, that is not causing severe shortness of breath the management is with admission, oxygen, and reassessment in 24 hours.
o If the pneumothorax was 1-2cm aspiration should be attempted
o >2cm, a chest drain should be inserted.
Tension pneumothorax
trauma to chest wall that creates a one-way valve that lets air in but not out of the pleural space.
PE prophylaxis
increased risk: LMWH e.g. enoxaparin
TED stockings
PE signs/symptoms
• Shortness of breath
• Cough with or without blood (haemoptysis)
• Pleuritic chest pain
• Hypoxia
• Tachycardia
• Tachypnoea
• Cyanosis
• Crackles, rub, pleural effusion
• Low grade fever
• Haemodynamic instability causing hypotension
• Deep vein thrombosis such as unilateral hot, red, leg swelling and tenderness
o Proximal (iliofemoral – most likely) and distal (popliteal – least likely)
Diagnosis of PE
USS: DVT
CXR: Normal early on before infarction, basal atelectasis, consolidation
ABG: respiratory alkalosis: high respiratory rate to blow CO2 off (low CO2 – blood becomes alkalotic). pO2 will be low
Wells score:
- likely CTPA
- unlikely d dimer, then CTPA
ECG: S1Q3T3 patterns
troponin and BNP: right heart strain
Echo
PE management
Initial management: LMWH
Long term: warfarin, NOAC or LMWH
- if warfarin (continue LMWH for 5 days)
- DOACs (direct-acting oral anticoagulants) are essentially oral anticoagulants that are not warfarin e.g. apixaban, dabigatran and rivaroxaban
- LMWH: pregnancy and cancer
Low risk: home
High risk: might require thrombolysis (alteplace), oxygen, analgesia
Pulmonary hypertension
increased resistance and pressure of blood in the pulmonary arteries. Causes strain on right hand side of heart
Normal pressure is 12-20 mmhg. High >25
Pulmonary hypertension Ix
ECG: RVH. large R waves in V1-3 and S eaves in V4-6
CXR: Dilated pulmonary arteries, RV hypertrophy & cardiomegaly
Raised NT-porBNF
measureed right heart catheter
Primary pulmonary hypertension management
- exclude secondary causes
- prophylactic warfarin
- o2 if hypoxic
- pulmonary vasodilators
Ca2+ channel blockers (oral nifedipine ,diltiazem)
Endothelin antagonist (Oral Bosentan, Macitentan)
PDE5-inhibitor (Oral Sildenafil/Tadalafil)
Prostanoids (IV Epoprostenol or Inhaled Iloprost)
Soluble Guanylate Cyclase stimulator (Riociguat) - Lung transplant
Obstructive Sleep Apnoea
Obstructive sleep apnoea is caused by intermittent collapse of the pharyngeal airway during sleep. characterised by apnoea episodes during sleep where the person will stop breathing periodically for up to a few minutes.
OSA management
remove undelrying cause stop drinking, smoking and lose weight CPAP Mandivbualr devices Surgery
Acute bronchitis
short-term inflammation of the bronchi (large and medium-sized airways) of the lungs.
arises from Strep. pneumoniae/H. influenzae infections, or in people with COPD.
acute bronchitis signs/symptoms
- Productive cough
- Wheeze
- Breathlessness
- Mild fever
- Normal chest examination
- Normal chest X-ray
- May have a transient wheeze
acute bronchitis management
self limiting
antibiotics only if chronic lung disease e.g. copd and amox
Metapneumovirus
lower respiratory tract infection, particularly in young children and infants
Bordetella pertussis
whooping cough (acute trachea-bronchitis)
whooping cough signs/symptoms
mild coryzal symptoms (around 2 weeks), a low grade fever and possibly a mild dry cough. week or more: more severe coughing fits start after a week or more.
These involve sudden and recurring attacks of coughing with cough free periods in between. This is described as a paroxysmal cough.
whooping cough Iv
nasopharyngeal or nasal swab with PCR testing or bacterial culture
more than 2 weeks patients can be tested for the anti-pertussis toxin immunoglobulin G
Whooping cough management
Azithromycin, erythromycin and clarithromycin can be beneficial in the early stages (within the first 21 days) or vulnerable patients
Pneumonia
Infection involving the distal airspaces usually with inflammatory exudation (“localised oedema”).
Fluid filled air spaces lead to consolidation (normally liquid) due to infection which impairs gas exchange
Pneumonia bacteria causes
Streptococcus pneumoniae (50%)
Haemophilus influenzae (20%): elderly and underlying lung condition
Moraxella catarrhalis in immunocompromised patients or those with chronic pulmonary disease
Pseudomonas aeruginosa in patients with cystic fibrosis or bronchiectasis
Staphylococcus aureus in patients with cystic fibrosis and after influenza episode
atypical: legionella (hyponatraemia/SIADH/GI disturbance), mycoplasma pneumonia (erythema multiforme), chlmaydophilia pneuomiae, chlamydia trachomatis , chlamydia psittaci, coxiella burnetti
CURB-65 Score
• C – Confusion (new disorientation in person, place or time)
• U – Urea > 7
• R – Respiratory rate ≥ 30
• B – Blood pressure < 90 systolic or ≤ 60 diastolic.
• 65 – Age ≥ 65
o Score 0/1: Consider treatment at home
o Score ≥ 2: Consider hospital admission
o Score ≥ 3: Consider intensive care assessment
CAP antibiotics
0-2 Mild/Mod: Amoxicillin 1g tds IV/PO: Total 5 days. If penicillin allergic: Doxycycline PO 200mg on day 1 then 100mg od or IV Clarithromycin* if NBM (total 5days)
3-5 Severe: Co-amoxiclav IV 1.2g tds + Doxycycline PO 100mg bd: 7 days . If penicillin allergic: IV Levofloxacin 500mg bd monotherapy
ICU/HDU or NBM: Co-amoxiclav IV 1.2g tds + Clarithromycin* IV 500mg bd. If penicillin allergic: IV Levofloxacin 500mg bd monotherapy)
Step down: Doxycycline 100mg bd for ALL patients with severe CAP TOTAL IV/PO 7 days
HAP antibiotics
Non severe: PO Amoxicillin (Total 5 days) If penicillin allergic: Doxycycline 100mg bd): TOTAL 5 days
Severe: IV Amoxicillin + Gentamicin. If penicillin allergic: IV Co-trimoxazole + Gentamicin)
Step down: PO Co-trimoxazole TOTAL IV/PO 7 days
Aspiration pneumonia antibiotics
Non severe: PO Amoxicillin + Metronidazole. If penicillin allergic: PO Doxycycline 100mg bd + Metronidazole) TOTAL 5 days
Severe: IV Amoxicillin + Metronidazole + Gentamicin. If penicillin allergic: replace amoxicillin with PO Doxycycline or IV Clarithromycin*
Step down: PO Amoxicillin + Metronidazole
o If penicillin allergic: Doxycycline 100mg bd + Metronidazole TOTAL IV/PO 7 days
Intrapulmonary lung abscess
Lung abscess is a type of liquefactive necrosis of the lung tissue and formation of cavities (more than 2 cm) containing necrotic debris or fluid caused by microbial infection.
lung abscess signs/symptoms
- Tumour-like
- Chronic malaise (general feeling of discomfort) and swinging fever
- Weight loss common
- Lethargy, tiredness, weakness
- Cough ± sputum (foul smelling)+/- haemoptysis
- Pleuritic chest pain
- Finger clubbing, crepitations and anaemia
Lung abscess Iv
- Blood: FBC, ESR, CRP, blood cultures
- Sputum: microscopy, culture and cytology
- CXR: walled cavity often with fluid level
- CT: exclude obstruction
- Bronchoscopy: diagnostic specimens
Lung abscess management
- Antibiotics: guided by culture results – continue until healed (4-6 weeks)
- Postural drainage
- Repeated aspiration
- Surgical drainage may be required
Septic emboli
embolism that is infected with bacteria, resulting in the formation of pus.
Can cause right sided endocarditis, infected DVT and septicaemia
Septic emboli management
- Treat underlying infection and cause
- Antibiotics – culture
- draining an abscess.
- removing or replacing infected prostheses.
- repairing a heart valve damaged by the infection
Bronchiectasis
Abnormal localised irreversible (fixed) dilation and thinning of the bronchial tree (bronchi). Usually due to fibrous scarring following infection (pneumonia, tuberculosis, cystic fibrosis) and chronic obstruction (tumour) which pulls open the airways
signs/symptoms of bronchiectasis
- Persistent cough with persistent sputum production
- Intermittent haemoptysis
- Recurrent “chest infections”
- Recurrent antibiotic prescriptions
- No response to antibiotics
- Short lived response to antibiotics
- Finger clubbing, course inspiratory crepitations, wheeze
bronchiectasis diagnosis
- Clinical: Cough productive of sputum, chest pain and recurrent LRTIs
- Sputum Culture: S. aureus, Pseudomonas, HiB
- Other: IgA deficiency, CF (sweat test), aspergillus precipitins
- CXR: dilated + thickened bronchi (cystic shadows)
- HRCT: High-resolution computed tomography: Signiant ring – thicken airway and next to it is a pulmonary artery and however the bronchi is bigger than the artery
- Spirometry: obstructive pattern with reversibility assessed
- Bronchoscopy: assess site of haemoptysis, exclude obstruction and obtain samples for culture
bronchiectasis management
physio, antibiotics, bronchodilators and anti-inflammatory agents
itraconazole
low dose macrolides antibiotics: pseudomonas colonised individuals
bronchiectasis
Antigenic drift
variation in viruses that involves the accumulation of mutations within the genes that code for antibody-binding sites
influenza management
suspected flu and risk of complications:
- oral oseltamivir 75mg
- inhaled zanamivir 10mg
Post exposure prophylaxis
- chronic disease or immunosuppression (within 48 hours)
- oral oseltamivir 75mg for 10s
- inhlaed zanamivir 10mg for 10 days
TB systemic symptoms
lethargy, fever, night sweats, wt loss, cough (with haemoptysis), lymphadenopathy, erythema nodosum
Tb Iv
Ziehl Neelsen stain
Mantoux test
Interferon gamma release assay
CXR
Cultures: sputum, mycobacterium blood cultures and lymph node biopsy
Nucleic Acid Amplification Test
Latent TB management
Isoniazid and rifampicin for 3 months
Isoniazid for 6 months
Acute pulmonary TB Mx
R – Rifampicin for 6 months (red/orange urine/tears and can affect COCP)
I – Isoniazid for 6 months – peripheral neuropathy – Vitamin B6 prophylactically
P – Pyrazinamide for 2 months (hyperuricaemia: gout)
E – Ethambutol for 2 months (colour blindness and reduce visual acuity)
Isolate for 2 weeks
CF gene and variants
chromosome 7 (long arm)
delta F508 (5 classes) G551D mutation (type II mutation)
CF pathology
o Don’t get activation of the channel and the chloride stays in the cell (reduced chloride secretion) and sodium (loss of inhibition of sodium channels – excessive resorption) comes into the cell. Water follows the sodium causing the lumen to dry out and not be salty – dehydration of the lumen
CF complications
Thick pancreatic and biliary secretions that cause blockage of the ducts, resulting in a lack of digestive enzymes such as pancreatic lipase in the digestive tract (Biliary obstruction, fibrotic pancreas and obstructive hepatitis)
Intestinal Blockage
Low volume thick airway secretions that reduce airway clearance, resulting in bacterial colonisation and susceptibility to airway infections
Congenital bilateral absence of the vas deferens in males.
Bronchiectasis
signs/symptoms of CF
chronic cough recurrent resp infections steatorrhoea (lack of pancreatic lipase) abdominal pain poor wt and ht gain crackles and wheeze on auscultation
CF diagnosis
newborn blood spot
sweat test
genetic testing: amiocentesis or chorionic villous sampling
Selective IgA deficiency
only class that can be transported across epithelium barriers in mucus secretions
Common variable immunodeficiency (CVID)
is an immune disorder characterized by recurrent infections and low antibody levels, specifically in immunoglobulin (Ig) types IgG, IgM and IgA
Severe congenital neutropenia (KOSTMANN SYNDROME)
Neutrophil development and mobilisation (AD)
Kostmann syndrome Mx
Immunoglobulin replacement therapy (IVIg) – intravenous immunoglobin
Aggressive management of infection
- Oral/intravenous antibiotics and anti-fungals
- Surgical draining of abscesses
Definitive therapy
- Haematopoietic stem cell transplantation
- Specific treatments: CGD – Gamma interferon therapy
Gene therapy
Treatment with recombinant G-CSF: Reduces infections
Leukocyte adhesion deficiency
Very rare autosomal recessive primary immunodeficiency
Results in failure of neutrophil adhesion and migration to endothelial adhesion molecules
Chronic granulmatous disease
Deficiency of the intracellular killing mechanism of phagocytes: absent respiratory burst
X-linked SCID
45% of all severe combined immunodeficiency
Results in inability to respond to cytokines
failure of T cell and NK cell development
production of immature B cells
DiGeorge syndrome
- Deletion of chromosome 22q11
- Failure of production of CD4+ and CD8+ T cells
- Abnormality in early development of 3rd/4th pharyngeal pouch.
- Structural abnormalities incl. absence of a thymus – no T cell maturation.
Type II hypersensitivity
Goodpasture’s disease:
autoimmune disease that affects the lungs and kidneys
o pulmonary alveolar haemorrhage
o kidney disease (glomerulonephritis)
Defined by the presence of autoreactive antibodies to the α3 chain of type IV collagen present in the basement membranes of alveoli and glomeruli
Type III hypersensitivity
• In the presence of excess antigen, antibody binds forming small immune complexes. These are trapped in small blood vessels, joints and glomeruli results in: • Activation of complement → cell lysis → opsonisation • Opsonisation → Antibody-mediated phagocytosis • Infiltration and activation of neutrophils and macrophages → tissue damage
PEX
failure of peripheral tolerance mechanisms due to defective/absent regulatory T cells (Tregs)
