Respiratory Flashcards
What is spirometry?
assesses lung function by measuring expiration volume after max inhale
differentiates between obstructive and restrictive lung disease
Includes FEV1, FVC, and % (normal 0.7)
What is FEV1? Normal values?
Forced expiratory volume in 1’s
Volume exhaled in 1st second after deep inspiration and forced expiration
80% or greater than predicted is normal
What is FVC? Normal values?
Forced Vital Capacity
Total volume of air that patient can forcibly exhale in one breath
- *80% or greater** than predicted is normal
- *Low = airway restriction**
How are the results of spirometry expressed?
FEV1 / FVC
in %, best of three readings
Normal is >0.7
What does it mean to have an obstructive spirometry pattern?
FEV1/FVC below 0.7 = obstruction
What does it mean to have a restrictive spirometry pattern?
Normal FEV1/FVC > 0.7
but FVC is low = restriction
Name a few obstructive diseases?
COPD, asthma, emphysema, bronchiectasis, bronchiolitis,
cystic fibrosis
Name a few restrictive diseases?
Pulmonary
Pulm fibrosis, Pulm oedema, TB !
Non pulm
kyphoscoliosis, neuromuscular disease, connective tissue disease, obesity, pregnancy
What is reversibility?
Bronchodilator responsiveness - see if lung function gets better with meds
If
reversible - + asthma likely diagnosis
not reversible - fixed obstructive patho
partially reversible - coexist
How might you assess reversibility?
Spirometry → Administer bronchodilator → repeat
Test with 400 microgram salbutamol
Compare and contrast asthma & COPD?
Asthma
variable airflow obstruction
reversible
COPD
fixed airflow obstruction
may be mixture
What is COPD?
Chronic Obstructive Pulmonary disease
persistent airflow limitation, not fully reversible
progressive, assoc chronic bronchitis & empysema
What is chronic bronchitis?
Cough with sputum for 3 months
2 or more years
- *Hypertrophy & hyperplasia of bronchi** = bronchoconstriction, - airflow,
- *narrowing of airways**
What is emphysema?
Histological!
Enlarged airspaces distal to terminal bronchioles, with destruction of alveolar walls
loss of elastic recoil = - expiratory airflow
loss of alveoli = loss of SA for exchange
= airway collapse during expiration
Risk factors for COPD?
Cigarette smoke
Occupational exposure to pollutants, dust, chemicals, smoke
alpha-1 antitrypsin deficiency
recurrent lung infections
How might cigarette smoke cause COPD?
Mucus gland hypertrophy in large airways
= increase in WBC (N, M & L) & release of inflam mediators →
structural changes in lung = emphysema
Presentation of COPD (4)?
Productive cough
with white or clear sputum
Breathlessness - even at rest
prolonged expiration, poor chest expansion
lungs hyperinflated = barrel chest
Pursed lips on expire = prevent alveolar & airway collapse
Extra-pulmonary manifestations of COPD?
Pulmonary hypertension
= fluid retention, peripheral oedema
= (severe) RV hypertrophy, cyanosed
Weight loss, reduced muscle mass, general weakness, osteoporosis, depression
Function of alpha-1 antitrypsin in normal person?
secreted by liver, acts in parenchyma
Inhibits elastase
= protease that breaks down elastin
Elastin = important for
structural integrity of alveoli
How might alpha-1 antitrypsin deficiency caused COPD present?
Early onset, family history!
auto recess
smoking still +++ risk tho
a-1 a = hepatic secreted elastase inhibitor, deficiency = breakdown of alveoli = emphysema
Investigations for COPD (4)?
Lung function test
FEV < 80
FEV1/FVC < 0.7 = obstruct
CXR / CT
normal / hyper inflated lungs = low flattened diaphragm, long narrow heart shadow
reduced peripheral lung markings
bullae = airspace >1cm, complete destruct of lungs
FBC = chronic hypoxia
alpha-1 antitrypsin levels / genotypes
esp in premature disease & lifelong non smokers
What is peak flow?
= test of peak flow rate during forced expiration following max inspiration
Varies with:
diurnal (high afternoon low early)
age, gender, height
How might you differentiate between asthma & COPD (in investigations)?
Repeat peak flow to exclude asthma
Classification of stages of COPD?
Stage 1 - FEV1 <80%
Stage 2 - FEV1 50-79
Stage 3 - FEV1 30-49
Stage 4 - FEV1 <30%
Lifestyle tx before pharm tx (5)?
stop smoking!!! duh
pneumococcal and influenza vaccinations
pulmonary rehab if indicated
make a self management plan with patient
treat comorbidities
Pharma tx principles for COPD?
1st line = SABA / SAMA
2nd- Steroid responsive / asthma features?
yes - LABA + ICS
no - LABA + LAMA
3rd
(LABA + LAMA) + ICS 3 months
= if 2nd & still affect QoL
(LABA + LAMA) + ICS
= if 1 severe or 2 modern exa / year
(LABA + ICS) + LAMA
QoL or 1s2m/y
What are SAMA / LAMAs? Examples?
Antimuscarinics = competitive inhibitor of Acetylcholine → reduce smooth muscle tone
= bronchodilation
-ium ending!
Short = ipratropium
Long = titropium, glycopyroonium, aclidinium
What are SABA/LABAs? Examples?
Beta 2 agonists = smooth muscle relaxation, (K+ to cells)
Short = salbutamol. terbutaline
Long = salmeterol, formoterol
What are ICS? Examples?
Inhaled corticosteroids = alternates transcription so reduces IL & chemokines, increases antiinflam proteins → reduce mucosal inflammation, widen airways & reduce mucus secretion
Examples = beclometasone, budesonide, fluticasone
Pathophysio of asthma!
Airflow limitation
Airway hyper responsiveness
Bronchial inflammation → plasma exudate oedema, smooth muscle hypertrophy, mucus plugging and epithelial damage
Cells involved in airway inflammation in asthma?
Main mediator = IgE
Mast cells → histamine = bronchoconstrict, prostaglandin, cytokine, IL345
Eosinophils → by IL3 & 5
Dendritic cells & lymphocytes: present allergens to lymphocytes & release cytokine
Two main types of asthma?
Allergic / eosinophilic asthma (70%)
allergens & atopy
Non-allergic / non eosinophilic (30%)
Exercise, cold air & stress
smoking, obesity
Non-acute attack symptoms of asthma?
Nocturnal worse: cough / dyspnoea
frequent in children
intermittent dyspnoea, wheeze, sputum
May be linked to ‘provoking †’ = allergens, infections, men-cycle, exercise, cold air
Features of an asthma attack?
reduced chest expansion / prolonged expiratory time / bilateral expiratory polyphonic wheezes / tachypnoea
severe = silent chest / cyanosis (PaO2 < 8kPa) / bradycardia / PEFR < 33%
Immediate management if life threatening attack?
Oxygen to maintain O2
Nebulised 5mg salbutamol + ipratropium - repeat / IV
Prednisolone ( ± hydrocortisone IV)
ABG, repeat in 2hrs
PEFR regularly
Oximetry → SaO2 > 92%
CXR if no response
How might you diagnose asthma?
RCP3 questions - nocturnal / usual in a day? / interfere with daily living?
1- Lung function test
- Nitric oxide FeNO test
- Peak flow readings
blood & sputum test → eosinophilia in sputum = specific!
Skin prick allergen test
Asthma control test
25 good, 20-24 on target, 20 = off
What will an asthmatic lung function test look like?
Peak expiratory flow rate PEFR - measure on waking, prior to b.d. & before bed, after bronchodilator
→ diagnostic if > 15% improvement on FEV1 or PEFR follow b.d.
Spirometry = assess reversibility
Exhaled nitric oxide = assess efficacy of corticosteroids
Carbon monoxide test = normal
How might you distinguish asthma from COPD?
COPD = later disease, smokers
Progressive short of breath with wheeze as a part of symptom complex
= less day to day variation
winter symptoms and sputum production in COPD
* but can overlap!
Treatment algorithm for asthma in >17? (NICE)
Short term, 1st: SABA
Maintenance 1st: ICS + SABA
+ LTRA
then onwards, LTRA optional
+ LABA
+ LABA in MART
Sebastian’s steroids went ultra fast in a lazy supermarket
MART = maintenance and reliever therapy
Treatment algorithm for asthma in 5-16?
Short = SABA
Maintenance
ICS + SABA
ICS + LTRA
ICS + LABA
Then
Maint: ICS + LABA in MART
Short: ICS + LABA in MART
Then
Main: up ICS + LABA in MART or fixed
Short: ICS + LABA in MART
or change to SABA
Beta agonists for asthma
Effective time, examples and type of agonist?
Short acting BA - 4 hours
Salbutamol = partial agonist
Terbutaline
Long acting BA - 12 hours
Salmeterol
Formoterol = full agonist
How does LABA last longer and what should you be careful of with badly controlled asthmatics?
LABA = longer since more lipophilic = remain in tissue longer
In badly controlled asthmatics - high concentration may lead to tolerance due to B2-receptor desensitisation
Types of ICS for asthma?
= semi-synthetic glucocorticoids
Budesonide, beclomatasone, prednisolone
(mineralo involves aldosterone so Na+)
What is an LTRA?
Leukotriene receptor antagonist
e.g. montelukast
What is bronchiectasis?
Chronic infection of the bronchi & bronchioles → airway distortion & dilatation with inflam process in wall of the airway
Results from pulmonary inflammation & scarring due to infection, bronchial obstruction or fibrosis
Risk factors for bronchiectasis?
women > men, increase w/age
pathological endpoint for many diseases
HIV, UC, RA!
- *post INFECTIONS**
e. g. pneumonia, TB, measles, pertussis
Causes of bronchiectasis?
Infections!!
again, pneumonia, TB, measles, pertussis, whooping cough
Congenital
CF, Kartagener’s
Mechanical obstruction
foreign body, lymph node, tumour
Briefly describe pathophysiology of bronchiectasis (again)?
Failure of mucociliary clearance + impaired immune = insult to bronchial wall → uncontrolled inflammation → bronchitis → bronchiectasis → fibrosis
Present - bronchiectasis?
Productive cough with large amounts of foul smelling, discoloured (khaki / green) sputum
occasional haemoptysis
Infection = + sputum volume, + purulence
- *Finger clubbing**! esp CF
- *Chest pain**!
Dilated, thick bronchi on CT
Investigations for bronchiectasis?
Usually lower lobes affected!
CXR
cystic shadows: cysts w/ fluid
dilated bronchi & thickened walls = tramlines & ring shadows
High Res CT
Thickened, dilated bronchpi + cysts
always > assoc. blood vessels
Spirometry = obstructive
Bronchoscopy to sputum culture!
Common causal organisms for bronchiectasis?
H. influenza
S. pneumoniae
S. aureus
P. aeruginosa
Treatment for bronchiectasis?
Improve mucus clearance
chest physio, mucolytics, postural drain
- *Antibiotics**
- *H. influenza** = amoxi / co-amoxiclav / doxycyline but if resistant = IV cephalosporin
- *S. aureus** = flucloxacillin
- *P. aeroginosa** = high dose oral ciprofloxacin
Anti-inflammatory agents = long term azithromycin can reduce exacerb freq
What is cystic fibrosis?
Disease of exocrine gland function affecting mainly caucasians
auto recess!
multi system usually w/ pancreatic insuff
Pathophysio of cystic fibrosis?
Mutation on chromosome 7
= defective CF transmembrane regulator (CFTR) protein
defective Cl- secretion & increased Na+ absorption in airways = increased H2o absorp → thickened secretion in number of organs
How might CF manifest in the lungs?
= dehydrated airway surface liquid,
= mucus stasis, airway inflam & recurrent infection
predisposed to chronic pulmonary infections + progressive obstruct
final = bronchiectasis
How might CF present extra-pulmonarily?
Salty sweat!!
Reduced pancreatic enzymes → pancreatic insufficiency (DM & steatorrhoea)
Distal intestinal obstruction syndrome
= reduced GI motility, maldigest & malabsorp
Male urogenital abormality, female amenorrhea
How might you test for cystic fibrosis?
fam hist + clinical hist
Sweat test
= high [Na+] & [Cl-], >60mmol/L
Genetic screening for CF mutations
Faecal elastase test
tests for protease - produced by pancreas
in CF - low to none
cough swab, sputum culture
Treatment for cystic fibrosis?
Stop smoking
FEV1 & BMI every appt
Prophylactic
antibiotics
pseudomonal & flu vaccine
Pharm
BA & ICS = symptomatic relief
Mucolytics = clear airway mucus
Replace pancreatic enzyme
Bilateral lung transplant
Antibiotics for -
s. aureus
h. influenza
MRSA
p. aeruginosa
- *s. aureus** = flucloxacillin
- *h. influenza** = amoxicillin
- *MRSA** = rifampicin & fucidin
- *p. aeruginosa** = ciprofloxacillin & nebulised colomycin
Complications for cystic fibrosis?
gallstones, liver cirrhosis
end stage = bronchiectasis
What is sarcoidosis?
Multisystem inflammatory disease affecting the lungs & intrathoracic lymph nodes
= interstitial lung disease
Pathophysio of sarcoidosis?
T cell mediated granulomatous disease
non-caseating sarcoid granulomas consisting mainly of T cells
mainly mediastinal lymph nodes & lung
risk factors for sarcoidosis?
20-40 years, women
afro-caribbeans more frequent
& severe - particularly extra-thoracic disease
fam hx (first degree)
Presentation - sarcoidosis
Incidental find on CXR common
= infiltrate & extracellular matrix deposition in lung distal to terminal tubule
lymphadenopathy = swole lymph nodes in neck!
painless, no swallow difficulty
can affect any organ but predilection to lung & lymph node
cancer symptoms / systematic
Acute sarcoidosis - symptoms?
Erythema nodusum - on shins, thigh & forearm ± polyarthralgia
both may spontaneous resolve / come and go
Investigations for sarcoidosis?
DIAG = tissue biopsy
→ non-caseating granuloma
**CXR for staging** Bronchoalveolar lavage (BAL) - increased lymphocytes in active disease
Lung function test
Blood = raised ESR, ACE!!!
LFT, Ca2+, lymphopenia
Staging for sarcoidosis?
- *0** - normal
- *1** - bilateral hila lymphadenopathy (BHL)
- *2** - pulm infiltrate with BHL
- *3** - pulm infiltrate without BHL
- *4** - prog pulm fibrosis, bulla formation = honeycombing & bronchiectasis
Treatment for sarcoidosis?
No treatment for
those with bilateral hilar lymphadenopathy = no tx = spont resolve
symptomatic at stage 1, asymptomatic at stage 2
treat acute, transplant for severe
How might you treat acute sarcoidosis?
Bed rest
NSAIDs
Corticosteroids
= prednisolone oral then wean
severe = IV methylpred
steroid resistant = methotrexate but needs close monitoring
What is idiopathic pulmonary fibrosis?
Chronic condition characterised by progressive fibrosis of unknown aetiology
= interstitial lung disease
Risk for IPF?
commonly related to other interstitial diseases - sarcoidosis, chronic hypersensitivity pneumonitis, autoimmune stuff
50+ age!
fam hx - familial PF
What is interstitial lung disease?
group of diseases affecting the lung insterstitium (tissue & space around air sacs of lungs)
Features of IPF?
- *Chronic exertional dyspnoea**
- *bilateral inspiratory crackles**
- *clubbing**
- *acrocyanosis** (peripheral discoloration indicative of cyanosis)
Investigations for IPF?
High Res CT = key
in basal lung / periphery
subpleural reticulation / reticular opacity
traction bronchiectasis
emphysema / loss of lung volume
honeycombing
Lung function tests
Bloods
Biopsies - bronchoalveolar lavage / transbronchial biopsy etc
Management in IPF?
Supportive
O2, exercise, opiates
Treat cough
Pharma w/ specific criteria
Pirfenidone (anti-inflam), nintedanib (slow fibrosis)
Lung transplant where appropriate
Pulmonary hypertension - criteria?
using
mean pulmonary artery pressure (mPAP)
Conditions associated with pulmonary hypertension?
1e = Connective tissue disease - SLE
Left heart failure - MI / systemic
(test using brain natriuretic peptide, ECG etc)
COPD, pulmonary embolism
Sarcoidosis, glycogen storage disease & haem disorders
How might you treat pulmonary hypertension?
Warfarin - intrapulmonary thrombosis
Diuretics for oedema
Prostanoids = IV epoprostenol
Oral endothelin receptor antagonist = bosenten
Phosphodiesterase-5 inhibitors = sildenafil
What is hypersensitivity pneumonitis?
ILD
Inhalation of allergens provoking a hypersensitiivity (type 3 / 4 reaction)
Nature of hypersensitivity pneumonitis?
adult onset, occupation related!
Compare and contrast asthma x hypersensitivity pneumonitis?
- *Asthma**
- type I IgE
- inflam around airway (bronchial)
- eosinophilic inflam
- eventual - irreversible airway changes
- *Hypersensitivity pneumonitis**
- type III or type IV IgG
- inflam around alveoli and lung interstitium
- neutrophilic inflam
- eventual = fibrosis
Pathophysio of hypersensitivity pneumonitis?
allergic reaction to inhaled antigen → granulomatous inflammation of lung parenchyma
= sensitised by repeat inhalation of the antigen
- *acute / subacute** = recurrent
- *chronic** = fibrosis, emphysema & perm lung damage
Occupations at risk and subtypes of hypersensitivity pneumonitis?
Farmer’s lung = most common
exp to fungus in mouldy hay
Bird/pigeon fanciers lung = also common
exp to avian proteins & droppings
Cheese-workers lung = exp to mouldy cheese
Malt-workers lung = exp to mould malt
Humidifier fever! = contaminated humidifying systems in AC / humid in factories, esp printing works
Present - farmer’s lung?
acute dyspnoea & cough
hours after inhalation
may resolve upon withdrawal of antigen
earliest = bronchiolitis then = non-caveating granulomas comp = pulmonary fibrosis
Acute & chronic presentation for hypersensitivity pneumonitis?
fever, rigors, myalgia
dry cough, dyspnoea, crackles no wheeze, tight chest
→ related to lvl of exposure
chronic
- usually no hist of preceding acute symptoms
- partial improvement when remove trigger
- cyanosis / clubbing / weight loss
- T1 resp failure
How might you diagnose hypersensitivity pneumonitis?
- *CXR**
- fibrotic shadow in upperzone of lung (mottling / consol)
- diffuse small nodules / + reticular shadowing
- *Lung function test**
- reversible restrictive defect
- reduced gas transfer during acute attacks
Bronchoalveolar lavage
→ analyse lymphocyte count & CD4/8 ratio
How might you treat hypersensitivity pneumonitis?
acute
remove allergen, O2
oral prednisolone followed by reducing dose
chronic
avoid exposure
long term steroids
Name some defensive mechanisms that protects the respiratory tract from infections?
Skin!
- *Intestines**
- acidic stomach, enzymes, commensal bacteria, thick mucosa barrier
Urinary system
sterile & flows outwards
Vagina
acidic pH / mucus barrier / commensal bacteria
Defensive mechanism of the lungs to protect against pathogens in respi tract?
Mucus barrier & cough
Humoral & cellular immunity
WBC & soluble factors
Commensal flora
Swallowing
push into intestines = strong acid
Upper respiratory tract infections?
What is pharyngitis / tonsilitis?
Infections in throat that causes inflammation
tonsils = primarily affected = tonsilitis throat = pharyngitis
Causes of pharyngitis?
Viral = 80%
rhinovirus / adnovirus
Epstein Barr virus, acute HIV
Bacterial
Group A beta haemolytic strep pyogenes (GABHS)
Presentation for pharyngitis?
sore throat / fever
- *oropharynx & soft palate = red**
- *tonsils inflamed and swollen**
1-2 days → tonsil lymph nodes enlarge
Treatment for GABHS caused pharyngitis?
Amoxicillin
How might you decide if a sore throat is caused by a bacterial infection or not?
→ Centor criteria
3-4 positive = 40-60% likely bac
tonsillar exudate
tender anterior cervical adenopathy
fever over 38 degrees by hx
absence of cough
What is sinusitis?
Infection of paranasal sinuses
mostly bacterial sometimes fungal
Causes for sinusitis?
Strep pnuemoniae (40%)
Haemophilus influenza (30-35%)
assoc. Upper RI infect / asthma
Present / diagnosis of sinusitis (2 key)?
Frontal headache ± fever
Purulent rhinorhea = nasal cavity filled with mucus fluid
= purulent nasal discharge
Unilateral facial pain, potentially with tenderness
Treatment for sinusitis?
Nasal decongestant e.g. xylometazoline
- *Broad spectrum antibiotics**
e. g. co-amoxiclav (h.i. can be resistant to amoxicillin)
complications
brain abscess, sinus vein thrombosis, orbital cellulitis
Acute epiglottitis - what is it?
Inflammation of epiglottis
= flap of cartilage behind roof of tongue → depressed during swallow to cover windpipe
Risk / epidemiology of acute epiglottitis?
Formerly in children < 5y/o
severely ill, life threat
now = rare → HiB vaccine
adults
severe = h. influenza
can be from pharyngitis / other bac infect of airway
immunocompromised - AIDS
Clinical presentation for acute epiglottitis?
Sore throat
pain on swallowing = odynophagia
Inspiratory stridor = high pitched wheeze when breathing in
if long hx, fatigue, weight loss, diarrhoea
Investigate / results for acute epiglottitis?
Sagittal view
upper respiratory tract XR
= thumb sign
Treatment for HiB caused acute epiglottitis?
Doxycycline or co-amoxiclav
20% amoxicillin resistant
not susceptible to macrolides (erythromycin / clarithromycin)
What is whooping cough? What causes it?
disease of childhood, 90% <5 yo
caused by Bordatella pertussis = gram neg coccobacillus (rod)
Clinical presentation for whooping cough?
Chronic cough in spasms (<14d)
inspiratory whoop = in younger
usually end in diarrhoea
rhinorhoea, conjunctivitis
may px as subconjunc haemorrhage
Investigations & results for whooping cough?
Lungs clear to auscultation
Respiratory culture - 90% positive for B. pertussis [gram neg]
PCR/ ELISA for IgG against pertussis toxin
Treatment for whooping cough?
Antimicrobials = clarithromycin
reduce symptoms earlier (1-6 weeks), less effective later
Should eliminate carriage in household = chemoprophylaxis
Vaccination
acellular pertussis as a part of dTaP
Diagnose:
3y, M
prominent barking cough, febrile, has inspiratory stridor
febrile, cyanosed with intercoastal recessions
Croup / acute laryngotracheobronchitis
Cause & pathophysio for Croup / acute laryngotracheobronchitis?
Parainfluenza viruses
inflammatory oedema extend to vocal cords & epiglottis = narrow of airway
progressive airway obstruction = cyanosis
Treatment for croup?
Nebulised adrenaline for short term relief
Oral / intramuscular corticosteroids (dexamethasone) w/ oxygen & fluids
Pneumonia - what is it?
Acute lower respiratory tract infection
= inflammation of the lung parenchyma
People at risk of pneumoniae?
Immunocompromised
infants & the elderly
nursing home residents
Comorbidities
COPD, chronic lung diseases
people w/ impaired swallow conditions *neuro etc)
Diabetes, congestive heart
Pathology of pneumonia?
Bacteria translocate to normally sterile distal airway → overwhelm resident host defence → inflammatory response → bac cleared
Pneumonia symptoms?
(think of big 3 areas - not signs!)
Infection
fever, sweats, sputum
no sputum in atypical org
Chest
short of breath, pleuritic chest pain (worse on deep breath)
Illness
weakness, malaise
sometimes extra pulm features
rusty sputum & pleuritic chest pain, raised WBC, multi-lobar consolidation
- causing organism?
S pneumoniae
Differentiate S pneumonia from S aureus?
S pneumonia = multi lobar
S aureus = multi lobar + multiple abscess
flu like symptoms, ± sputum, neuro / GI features
upper lobe cavity
- causing organism?
Legionella spp.
(but exclude TB first as TB also upper lobe)
± sputum, pneumonia features with a rash - causing organism?
rash = mycoplasma spp. !
Signs of pneumonia?
Infection
+ HR, RR, low BP
fever, dehydration
Chest
= signs of lung consolidation on percussion & auscultation
dull to percussion
decreased air entry
crackles ± wheeze
increased vocal resonance
Investigations for pneumonia?
CXR
FBC + Biochemistry
WBC (= marker of sev)
C-reactive protein = inflammation marker, diag + assess
Pulse oximetry
Microbiological tests
CXR signs for pneumonia?
airspace opacification
filling of the alveoli with infectious material and pus
patchy → confluent as infection develops
air bronchograms
air-filled bronchi running through pus-filled alveoli
(black branches in white)
Microbiological tests for pneumonia?
Sputum culture & sensitivities
Urinary antigen
Legionella & S pneumonia
PCR
viruses & mycoplasma
Consider acid fast bacilli stain & culture (TB) if features suggestive
Community acquired pneumonia - causative organisms (6)?
Strep pneumoniae = most common
H influenza
Klebsiella pneumoniae
Atypical
Mycoplasma pneumoniae
Chlamydophila pneunominae
Legionella sp.
How might you assess severity of CAP?
using the CURB-65 score
CURB 65 criteria?
(pls know)
Confusion
Urea (> 7mmol/L)
might not be present in community so ignore
Respiratory rate (> 30 / min)
BP < 90/60
Age > 65
Response according to CURB 65?
0-1 mild, admit if special circ
2 - moderate - admit!
3-5 - admit & monitor closely
4-5 admit to critical care
(no urea in comm so 0, 1-2 mod, 3-4 severe)
CAP treatment based on CURB score? Tx duration?
mild 0-1
amoxicillin
alt: clarithromycin or doxycycline
moderate 2
amoxicillin plus clarithromycin
severe 3-5
IV co-amoxiclav + clarithromycin
alt: cefuroxime & clarithromycin
- *5 days** mild to mod, + if severe
- *14-21 days** S aureus, gram neg & legionella
Other indicators of severity for pneumonia?
- *Delerium** = confusion
- *Renal impairment** = + urea
Increased oxygen demand, hypoxaemia
+ RR, lactic acid production
BP drop
→ signs of sepsis!
Treatment for pneumonia
S. pneumonia
nature of bac
tx?
gram positive
alpha haemolytic optochin sensitive
beta lactam = amoxicillin, cefuroxime, cefotaxime
- *alt**
- *macrolides** = clarithromycin, fluoroquinolones, ciprofloxacin
Treatment for pneumonia
H. influenza
nature of bac
tx?
gram neg cocobacilli
- *beta lactam** = amoxicillin, co-amoxiclav
- *tetracyclines** = doxycycline
NOT macrolides!!
Treatment for pneumonia
S. aureus
nature of bac
tx?
gram pos
beta lactams = flucloxacillin, cefuroxime
if MRSA = vancomycin, linezolid
Treatment for pneumonia
Klebsiella pneumonia
nature of bac
tx?
gram neg, entero
beta lactam = co-amoxiclav, cephalosporins
General ‘atypical’ pathogen tx principle?
special antibiotics
=
macrolides
Erythro / claritho
fluoroquinolones
ciprofloxacin
tetracyclines
doxycycline
Legionella features?
warm water
tanks, AC, travel
severe illness, resp failure
extra pulmonary = diarrhoea, GI & consudion
Mycoplasma features?
younger adult, milder illness
extrapulm features = rash (erythema multiforme), haemolytic anaemia, Raynauds, bullous myringitis, enceph
Prevention of pneumonia?
Vaccine!
Polysaccharide pneumococcal vaccine for > 65
Pneumococcal conjugate for children
Complications of pneumonia?
Respiratory failure
Hypotension
due to comb of dehydration + vasodilation from sepsis
Parapneumonic effusion
Empyema
What is parapneumonic effusion? Investigate?
any pleural effusion secondary to pneumonia (bacterial or viral) or lung abscess
→ thoracocentesis to remove fluid from pleural space, aka pleural tap
→ CXR = signs of pleuritic effusion
What is of empyema?
pleural effusion, but fluid is infected by bacteria!
= pus / purulent fluid in pleural space
fluid = yellow / turbid, pH < 7.2, low glucose
Signs of empyema?
- *ongoing fever**
- *failure of WBC / CRP to settle on antibiotics**
Pleuritic pain (on deep insp)
Signs of pleural collection
= stormy dull percussion, reduced air entry
Treatment for empyema / complicated parapneumonic effusions?
Drainage - chest tube / cardiothoracici surgery
Antimicrobials
co-amoxiclav
meropenam for anaerobic coverage
Lung abscess - people at risk?
in aspiration pneumonia, inapp tx CAP
- *alcoholics, those with poor dentition**
- *metastatic infection** from right heart & venous system - IVDU, Lemierre’s
TB, septic emboli
Causative organisms & nature - lung abscess?
Strep milleri
= alpha haemolytic optochin resistant
Klebsiella pneumonia
& other gram neg bac
Anaerobes!!!
ensure microbio coverage
Treatment for lung abscess?
= prolonged antibiotics for 6 weeks +, surgical drainage if required
Hospital acquired pneumonia - criteria? signs?
Acquired at least 48 hours after hospital admission
new fever, purulent secretions,
new radiological infiltrates / CRP increase, + O2 requirements
Hospital acquired pneumonia - causative organisms?
S. aureus (& MRSA)
strongly ventilator associated
Pseudomonas aeruginosa
- *Acinetobacter baumanii**
- *Klebsiella pneumoniae**
- *E. coli**
Treatment for early onset hospital acquired pneumonia (CAP organisms)
Metronidazole
Beta lactams with inhibitor of beta lactamase = co-amoxiclav, piperacillin-tazobactam
General, go to antibiotic if hospital acquired?
Start broad then focus
- *→ doxycycline**
- *→ piperacillin-tazobactam or cefurioxime**
Treatment for s. aureus HAP?
beta-lactam = flucloxacillin, cefuroxime
if MRSA - vancomycin
Treatment - pseudomonas aeruginosa?
Anti-pseudomonal penicillin
= piperacillin-tazobactam
What is bronchitis - acute vs chornic?
acute = self limited inflammation of the epithelia of the bronchi due to upper airway infection
chronic = condition in COPD, cough > 3m in 2 conseq years
Signs & causes of bronchitis?
cough, often wheeze > 5 days
± phlegm
no fever / signs of infection!
majority viral, rarely bacterial in healthy adults
Investigate & treatment, bronchitis?
- *CXR** - normal
- *Viral & bacterial throat swabs** = PCR for resp viruses & mycoplasma, culture for others
Usually none if viral!
What is tuberculosis?
= infectious disease caused by mycobacterium spp. with significant morbidity & mortality world wide
→ HIV linked!
Causative organisms (4) & spread?
Mycobacterium
- tuberculosis* = most common
- bovis* = unpasteurised milk
- africanum*
- microti*
→ aerosolised droplet spread!
but not all infected will develop active disease!
Nature of mycobacterium? Stain used?
aerobes, slow growing (15-20h)
Acid fast bacilli
= resistant to staining by acid
use Ziehl-Neelsen stain
= goes red / pink
People at risk of tuberculosis?
Origin
immigration (sub-saharan africa), hotspots
immunosuppressed
age
HIV
therapy (chemo etc)
- *IVDU, alcohol, smoking**
- *malnutrition, homeslessness**
Subtypes (manifestations) of TB?
Primary TB
= first infection with mycobacterium spp.
Latent TB
= immune system contains the nfection & cell mediated immunity memory developed to bac
Reactivation TB / Post-primary TB
= majority! dormant → active
= depression of host immune system (older, severe infection)
Pathophysiology of primary tuberculosis?
bac + macrophages → granuloma
= primary Ghon focus
as it grows → cavity in apex of lung
bac expelled when patient coughs
Primary focus in mediastinum lymph node = Ghon complex
Nature of the granuloma formed in TB?
Caseating granuloma
on CXR: small calcified nodule,
often on lower of upper lobe / upper of lower lobe
Can also be found in GI!
ileocaecal region
TB presentation?
night sweats & weight loss!
anorexia, low grade fever, malaise
cough 3/52
chest pain
breathlessness
haemoptysis
Investigations for TB?
CXR
patchy / nodular shadow in upper zone w/ loss of volume, fibrosis
normal in miliary TB
Sputum
auramine-phenol fluorescent test
= highlights bac as yellow-orange on a green background
Ziehl-Neelsen stain = red if TB
Culture
solid = Lowenstein-Jensen slopes / Middlebrook agar
Nucleic acid amplication = differentiate m. tb from others
Lumber puncture & CSF exam
= miliary TB
Testing for latent TB?
Skin test = Mantoux test
= cell mediated response to underskin TB antigen
→ type 4 hypersensitivity reaction
false neg if miliary / immunosuppressed
Interferon gamma release assays (IGRAs)
= more specific as can use specific antigen (diff bet vac and TB)
e.g. ESAT-6 & CFP10
Treatment for TB?
NOTIFIABLE to PUBLIC HEALTH ENGLAND + contact tracing
RIPE!!
Rifampicin 6m
Isoniazid 6m
Pyrazinamide 2m
Ethambutol 2m
Mechanism & SE Rifampicin?
bac cidal, anti protein synthesis
SE red urine, hepatitis
Mechanism & SE Isoniazid?
bac cidal, anti cell wall synthesis
SE hepatitis & neuropathy
Mechanism & SE Pyrazinamide?
bac cidal
SE hepatitis, arthralgia / gout + rash
Mechanism & SE Ethambutol?
bac static, anti cell wall synthesis
SE optic neuritis
Prevention for TB?
active case finding to reduce
Vaccination
Bacillus Calmette–Guérin (BCG)
= live attenuated, from M bovis
= in UK = mostly in areas with incidence bc ? cost effective
(CXR for contact tracing)
What is respiratory failure?
Occurs when inadequate gas exchange in the lungs
→ ABG to sample
Types of respiratory failure & criteria?
Type 1
= hypoxaemia (PaO2 < 8kPa)
normal / low Co2
Type 2
= hypoxaemia (PaO2 < 8kPa)
hypercapnia (PaCO2 > 6.5 kPa)
Causes of respiratory failure?
Hypoxaemia = V/Q mismatch Hypercapnia = alveolar hypoventilation
reduced ventilation
increased dead space
diffusion limitation
What is the V/Q ratio?
V = ventilation
flow of air in and out of alveoli
Q = perfusion
flow of blood to alveolar capillaries
What does it mean to have / causes of a high V/Q ratio?
alveolae has poor perfusion
(compared to ventilation)
= vascular problem!
causes = e.g. pulm embolism
What does it mean to have / causes of a low V/Q ratio?
alveolar has poor ventilation
(compared to perfusion)
ventilation problem!
= hypoxaemia (low al O2 lvls)
causes = airway disease, interstitial lung disease → reduced ventilation
Causes of T1RF?
= hypoxaemia
pneumonia, pulm oedema
COPD, asthma
pneumothorax, pulm embolism = MC!!
Treatment for T1RF?
Usually responds well to oxygen therapy
Causes for T2RF?
→ hyperventilation
Exacerbation of obstructive lung disease
= COPD (most common)
asthma, cystic fibrosis, bronchiectasis
Respiratory depressants = opiate overdose
What should you not do for acute deterioration in COPD?
treat with high flow oxygen
→ can lead to oxygen induced hypercapnia
(from + V/Q mismatch & physiological dead space)
→ that’s why COPD / asthma O2 saturation target = 88-92%
What is a pneumothorax?
Collection of air within the pleural space = space between parietal & visceral pleura
Types of pneumothorax?
Spontaneous = sans trauma
older with underlying lung disease
younger with apical blebs
Traumatic
can be open (communicate with outside air and pleural space) or closed
What is a pleural bleb?
a small collection of air in the pleural space <1-2cm
Present - pneumothorax?
Sudden onset dyspnoea
Pleuritic chest pain!
Tachycardia
Reduced chest expansion
Diminished breath sounds
Hyper resonant to percussion
Investigations for pneumothorax?
CXR
Signs of tension pneumothorax?
tachycardia, tachypnoea
low O2 low BP
distended neck veins
CXR
Trachea deviated away from the affected side
Treatment for tension pneumothorax (& spontaneous pneumothorax)
Needle aspiration first
then chest drain
(for spont pneumothorax too)
(at midclavicular line 2nd intercoastal space)
What is pleural effusion?
Abnormal collection of serous fluid within the pleural space
can also be: simple fluid, blood, pus (empyema)
Function of the pleural fluids?
Lubricate pleural surfaces
Generates surface tension
Pathophysiology - pleural effusion/
Imbalance of fluid entry & exit within the pleural space
+ entry: inflammation, pulmonary hypertension, nephrotic syndrome, cirrhosis
- exit: inflam mediators, damage (chemo), physical compression, decreased intrapleural pressure
Causes of pleural effusion?
Transudate = minimal protein & cellular content
→ alteration in hydrostatic / oncotic pressure
Exudate = high protein & cellular content
→ infection or malignancy
Symptoms of pleural effusion?
Signs develop when >300ml
Signs localised to side of effusion
reduced chest expansion & breath sounds
stony dull percussion
reduced vocal resonance
reduced tactile vocal fremitus (vibration of chest wall when speaking)
CXR signs of pleural effusion & criteria?
Need minimum 200-250 ml of fluid to detect
→ on PA chest xray!
= dense white consolidations!
aka opacification
meniscus at the costophrenic angle :)
Investigations for assessment of pleural effusion?
CXR to confirm
→ Pleural tap (thoracentesis) & analysis
needle inserted under anaesthesia
guide under ultrasound
→ sample for - pH, cytology, microbiology
purulent in empyema
turbid = infected
milky = lymph fluid
transudate / exudate based on protein content
(usually 🔪 30g/L)
Treatment for pleural effusions?
Exudate → drain
Transudate → TUC
Pleurodesis = injection that causes adhesions of visceral & parietal pleura → prevent reaccumulation of effusion = e.g. tetracycline
What is Goodpasture’s syndrome?
Acute glomerulonephritis + pulmonary alveolar haemorrhage
presence of circulating antibodies against antigen in basement membrane of kidney & lung
Pathophysio & antibodies in Goodpasture’s syndrome?
Autoimmune
= type II antigen-antibody reaction → diffuse pulm haemorrhage, glomerulonephritis ± AKI/CKD
antibody = anti-GBM antibodies
Risk & epidemiology of Goodpasture’s syndrome?
adults (>16)
rare in children
common in men
Presentation - Goodpasture’s syndrome?
Upper RI infect symptoms
sneezing, nasal discharge, congest, runny nose + fever
- *Haemoptysis**
- *Acute glomerulonephritis**
Cough, tiredness
Anaemia
(from persistent intrapulmonary bleeding)
just for fun
if similar presentation to goodpasture’s but no antibodies & kidney less involved, in children?
Idiopathic pulmonary haemosiderosis
Investigations & diagnosis for Goodpasture’s?
Presence of anti-GBM antibodies in blood
CXR
transient patchy shadows / pulm infiltrates due to pulm haemorrhage
often in lower zone
Kidney biopsy
crescentic glomerulonephritis
Treatment for Goodpasture’s?
→ in some may spontaneously improve
Vigorous immunosuppresive treatment
= corticosteroids = prednisolone
Plasmaphoresis = remove antibodies from blood and back
Complications - Goodpasture’s
Renal failure
shock!
Some non-specific occupational lung disorders / complications?
Acute bronchitis / oedema!
Pulm fibrosis
Occupational asthma
Hypersensitivity pneumonitis
Bronchial carcinoma
What is coal worker’s pneumoconiosis?
Pneumoconiosis = accumulation of dust in lungs & reaction of tissues to its presence
→ inhalation of coal dust particles in 15-20 years
Presentation & Management - coal worker’s pneumoconiosis?
Asymptomatic mostly!
but High Res CT → round opacities in upper zone
avoid exposure to coal dust, claim compensation
What is silicosis? At risk populations?
Inhalation of silica particles (silica dioxide) = toxic to alveolar macrophages & fibrogenic
at risk: stonemasons / sand-blasters / pottery & ceramic workers / foundry workers
Presentation & management - silicosis?
Progressive dyspnoea & increased incidence of TB
avoid exp, claim compensation
Investigations & results - silicosis?
Potential PMH / current TB
CXR
diffuse nodular pattern in upper & midzone
thin streaks of calcification (egg-shell calcification) of the hilar zone
Spirometry
restrictive ventilatory defect
What is asbestosis? Who are at risk?
Inhalation of asbestos = banned now
widely used in roofing, insulation, fireproofing as resistant in heat & pH
mostly crocidolite (blue) = readily trapped in lung
Presentation - asbestosis?
Progressive dyspnoea, finger clubbing, bilateral basal end inspiratory crackles
+ risk pleural plaques and + risk mesothelioma & bronchial adenocarcinoma
Management for asbestosis?
only symptomatic manage
= corticosteroids
What is a (malignant) mesothelioma?
= tumour of the mesothelial cells of pleura
STRONGLY associated w/ ASBESTOS exposure
Aetiology & locations of mesotheliomas?
men, 40-70’s
Exposure to asbestos = cause
but only 20% have pulmonary asbestosis
Other locations = peritoneum, pericardium, testes
Presentation - mesothelioma
Severe chest pain
- *Weight loss, finger clubbing**
- *recurrent pleural effusions** → malignancy!
Signs of mets = lymphadenopathy, hepatomegaly, bone pain / tenderness, abdominal pain / obstruction
(invasion of chest wall possible → intercoastal nerves)
Diagnosis - mesothelioma
CXR & CT
= unilateral pleural effusion
= pleural thickening
Pleural biopsy
Bloody / straw coloured pleural fluid
Treatment - mesotheliomas
Surgery for extremely localised mesothelioma
Generally resistant to all surgery, chemo, radio
Poor prognosis :<
Wegener’s granulomatosis / Granulomatosis with polyangitis
- what is it?
Multisystem disorder characterised by granulomatous disease and vasculitis of small and medium cells
ANCA positive
Pathophysio of granulomatosis with polyangitis?
Neutrophils activated inappropriately by autoantibodies (Anti-neutrophil cytoplasmic antibodies ANCA) before tissue migration
→ neutrophil recruitment when there is no infection → granulomas & vasculitis
Presentation of granulomatosis with polyangitis?
Lesions in upper respi tract, lungs & kidneys
Severe rhinorrhea (congested) & subsequent mucosal ulceration → characteristic saddle nose deform
cough, pleuritic pain, haemoptysis
skin purpura or nodules
PN, arthritis
renal disease → rapid progressive glomerulonephritis
Differential for granulomatosis with polyangitis -
Churg-Strauss syndrome - what is it? Features?
affects small arteries, male
rhinitis / asthma, eosinophilia, systemic vasculitis
high eosinophil count
ANCA positive
Investigations & diagnosis for granulomatosis with polyangitis?
Bloods
c-ANCA positive
+ PR3 antibodies
raised CRP, ESR
CXR
nodular masses or pneumonic infiltrates with cavitation = clear migratory pattern
CT
diffuse alveolar haemorrage
Urinalysis → proteinuria & haematuria → if pos: renal biopsy
Treatment for GPA?
Depends on extent of disease
Severe disease → steroids
Azathioprine / methotrexate for maintenance
Bronchial carcinoma - types?
Two main types
Small cell lung carcinoma
Non SCLC - in which
squamous carcinoma
adenocarcinoma
large cell and differentiated carcinoma
carcinoid tumours
Small cell carcinoma - risk factors & source & nature?
STRONGLY assoc cigarette smoking
arises from endocrine cells
central bronchus
secretes polypeptide hormones
Presentation, tx & prognosis, small cell lung carcinoma?
often arises in a central bronchus
early development of widespread metastases
chemo = primary tx
poor prognosis
Small cell lung tumours - supportive treatment?
**Primary = chemotherapy** brachytherapy = radioactive source placed close to exams
Pleuritic drain - symptomatic relief
Stents for obstructions - SVC, tracheal
Small cell lung cancer - endocrine complications
= ectopic ADH, ACTH secretion
SIADH
Cushing’s syndrome
(also Lambert Eaton)
Non - small cell carcinoma - tx?
Often treated best to surgical oblation with lymph node sampling
chemo /radio for follow up
More susceptible to new therapy e.g. tyrosine kinase
Lung cancer most strongly associated with cigarette smoking?
Squamous cell carcinoma
Squamous cell carcinoma - nature & locations?
arise from epithelial cells
associated with production of keratin
central tumours, frequent central necrosis, loca spread
→ obstructive lesions of bronchus
→ late mets
What is a pancoast tumour?
Squamous cell carcinoma that start in the top part of the lung (the apex).
Associated with Horner’s syndrome
Symptoms of a pancoast tumour?
severe pain in the shoulder or the shoulder blade (scapula)
pain in the arm and weakness of the hand on the affected side
Horner’s syndrome
= flushing on one side of the face and that side doesn’t sweat. The eye on the same side has a smaller (constricted) pupil with a drooping or weak eyelid.
Most common lung cancer overall, also in non-smokers?
Adenocarcinoma
Nature of adenocarcinoma?
commonly associated w/ asbestos
arise from mucus-secreting glandular cells
central or peripheral
Features of adenocarcinoma?
Usually single lesions but may be multifocal / bilateral pattern
Peripheral lesions on CXR / CT
mets are common
Treatment for non-small cell lung cancer (80%)?
main = Surgical excision for peripheral tumours with no spread
Chemo ± radio = more advanced disease e.g. monoclonal antibodies
comp’s = radiation pneumonitis, fibrosis
Main lung lymphoma - name, type of cells, tx?
Baltoma
= Bronchus Associated Tissue Lymphoma
B cell lymphoma
responds to standard chemo regimes
Name for benign tumours in the lung & nature?
Hamartomas
Irregular proliferation of benign tissue not normally found in lung tissue
Common destinations for lung mets? (LBAB)
Liver
Bone
Adrenal glands
Brain
Common origins of lung mets
(causes of secondary lung cancer?)
Breast cancer
Bowel Cancer
Kidney cancer = most common!!
= renal cell carcinoma
Bladder cancer
Consequences of arterial thrombosis?
Coronary circulation = MI
Cerebral circulation = TIA / stroke
Peripheral circulation = peripheral vascular disease = claudication, rest pain, gangrene
STEMI ECG features?
ST elevation, tall T waves, LBBB, T wave inversion with pathological Q waves
Thrombolytic therapy for MI’s?
Streptokinase & tissue plasminogen activator
Consequences of venous thrombosis?
Deep vein thrombosis = usually in legs
Pulmonary embolism = lungs
If atrial septal defect = travel to arterial system = stroke, MI, TIA
Risk of DVTs?
Recent surgery
Genetics = predisposition (thrombophilias)
deficiencies: factor V Leiden, protein C or S, antithrombin
Acquired
Antiphospholipid syndrome
Lupus anticoagulant
Lifestyle
Long haul flights, pregnancy, obesity, cancer, immobility, synthetic oestrogen
Main features of antiphospholipid syndrome?
CLOT
Clots = usually venous
Livedo reticularis = lace like rash on lower limbs
Obstetric loss
Thrombocytopenia
How might you provide venous thromboembolism prophylaxis
Low molecular weight heparin
CI existing warfarin / DOAC
anti-embolic compression stockings
CI peripheral arterial disease
DVT features?
Calf swelling and tenderness
Dilated superficial veins
Colour changes
Oedema
Investigations for DVT?
Well’s score predicts risk of patient having DVT / PE
D-Dimer will exclude DVT, as is also raised in pneumonia, heart failure, pregnancy etc
Doppler ultrasound of the leg = DIAGNOSTIC
repeat 6-8 days after if suggestive Wells & D-Dimer positive
Pulmonary embolism diagnostic test?
CT Pulmonary angiogram CTPA
= preferred
CI contrast allergy / kidney impairment
Ventilation perfusion (VQ) scan = alt
DVT initial management
Anticoagulation
= apixaban or rivaroxaban
if symptoms < 14 days & symptomatic iliofemoral DVT
consider catheter directed thrombolysis
Long term anticoagulation - classes, indications & examples?
Direct acting oral anticoagulants DOACs
= apixaban, rivaroxaban, edoxaban & dabigatran
Warfarin = vitamin K antagonist
1st for antiphospholipid syndrome (+LMWH)
Low Molecular Weight Heparin LMWH
= Enoxaparin, dalteparin
1st in pregnancy
3m if reversible cause, >3m if unclear, irreversible, recurrent. 3-6m active cancer
How might you reverse anticoagulation in strokes?
Dabigatran (direct thrombin inhibitor)
= idarucizumab
rivaroxaban / apixaban (direct factor Xa inhibitor)
= Andexanet alfa
Warfarin = vitamin K, human prothrombin complex (alt fresh frozen plasma)
Long term tx for VT if anticoag is unsuitable?
Inferior vena cava filters
= for recurrent PEs & those unsuitable for anticoag
= act as a sieve allow blood to flow through while catching clot
How might you investigate unprovoked DVT or PE
check for antiphospholipid antibodies (antiphospholipid syndrome)
check for hereditary thrombophilia if 1st degree relative also affected by DVT / OE
What is Budd-Chiari syndrome?
Blood clot develops in hepatic vein, blocking blood flow (assoc. hypercoagulable states)
→ causes acute hepatitis
→ present
abdominal pain
hepatomegaly
ascites
