Please enable JavaScript.
Coggle requires JavaScript to display documents.
CR - Lower RTIs (Pneumonia) (i) (Risk factors (extremes of age, chronic…
CR - Lower RTIs (Pneumonia) (i)
intro
lower resp tract = trachea, bronchi + lung
lined by pseudo stratified ciliated columnar epithelium + mucus-producing goblet cells (mucociliary escalator - pathogen clearance)
if pathogens reach alveoli they are phagocytosed by alveolar macrophages
breakdown of lung defences -> infection
Pneumonia = acute lower RTI involving lung parenchyma (as opposed to connective/supporting tissue)
can be CAP or HAP (nosocomial, 48+hrs after admission) or HCAI (e.g. in a nursing home - thought to be similar to HAP but actually more like CAP)
important to distinguish as there are different causative organisms + hence different Tx
Risk factors
extremes of age
chronic lung disease
smoking
alcoholism
comorbidities
winter
general anaesthesia (lost gag reflex - aspiration risk)
surgery
opiate analgesia (reduced RR)
immunosuppression
decreased consciousness
mechanically ventilated (VAP = type of HAP that occurs 48+hrs after endotracheal intubation - incidence = 10-20% in those ventilated for >48hrs - 25-50% mortality)
Presentation
systemic signs
fever (but could see hypothermia in elderly)
rigors
malaise
myalgia
anorexia
cough (purulent sputum)
dyspnoea
tachypnoea
occasionally haemophtysis
pleuritic chest pain
sudden, intense, sharp, stabbing, burning pain when inhaling + exhaling
exacerbated by deep breathing, coughing, sneezing, laughing
caused by inflamm of parietal pleura
Dx
Hx
clinical exam
cyanosis
decreased chest expansion
dull percussion over area of consolidation
increased tactile vocal fremitus
Lab investigations
blood for culture
resp specimen
gram stain
culture
consider ZN stain
sputum or BAL in v sick/hospitalised patients
urine for legionella or pneumococcus antigen test
nost/throat swab for influenza PCR
FBC (WCC, CRP, ESR)
U+E
LFTs
ABG
CXR
Atypical (walking well) pneumonia
caused by atypical pathogens
mycoplasma pneumoniae
legionella pneumophila
chlamydia pneumoniae + psittaci
coxiella burnetii
difficult to Dx early
sensitive to antibiotics other than B-lactams
macrolides (clarithromycin)
tetracyclines (doxycycline)
fluoroquinolones (ciprofloxacin)
often isn't severe enough to require bedrest or hospitalisation
Viral causes
account for 15% of cases
resp viruses
influenza A+B
RSV
esp in young children + immunocompromised
part of systemic infection
CMV (esp in immunocompromised)
VZV (esp in pregnancy + immunocompromised)
measles (esp in unvaccinated children
TB can cause pneumonia
unresponsive to antibiotics
productive cough
haemoptysis
fever
night sweats
anorexia
weight loss
isolate patient with airborne precautions, inform IPC team
Prevention
risk factor modification
smoking
alcohol
good management of comorbidities
pneumococcal + influenza vaccines