medicine Flashcards
Causes of pneumonia
bacteria
virus
fungi(rare)
definition of pneumonia
infection of the pulmonary parenchyma resulting in a respiratory and constitutional symptoms accompanied by clincal examinations findings and/or a new infiltrate on chest x-ray consistent with pneumonia.
Anatomical classification
lobar pneumonia
bronchopneumonia
interstitial pneumonia
clinical classification
CAP(Typical and atypical)
Nosocomial - HAP/VAP/HCACP
Aspiration pneumonia
Pneumonia in immunocompromised host
CAP
occurs without prior contact to the healthcare system in OPD or within 48hours of hospital admission.
HAP
occurs 48 hours after admission and no signs of pulmonary infection on admisson
VAP
develops 48 hours or more on mechanical ventilation
HCAP
Occurs in non-hospitalized patients who has had significant contact with the health care system
what causes the clinical syndrome of pneumonia
the body’s inflammatory response against it causes the clinical syndrome of pneumonia
rare causes of pneumonia pathogenesis
Pneumonia can also rarely result from a hematogenous or contiguous focus of infection (e.g., tricuspid valve endocarditis, hepatic abscess etc.
predisposing factors to pneumonia
- smoking
- alcholism
- recent upper respiratory tract infections
- pre-existing lung diseases(COPD, bronchiectasis, lung cancer)
- Factors that reduce the host defenses against pnemonia
- Aspiration of gastric or nasopharyngeal secretions
- Bacteria introduced into lower respiratory tract.
still on predisposing
which medications
PPI
factors that reduce host defenses against penumonia
Reduce immune defenses and comorbid conditions (e.g Malignancy, diabetes, corticosteroid treatment, heart failure, renal failure) • Reduce cough reflex (e.g. stroke, sedating medications) • Disordered mucociliary clearance (e.g. anaesthetic agents ) • Bulbar or vocal cord palsy
CAP related microorganisms
S. pneumonia S. aureus K. pneumoniae H. influenzae and M. catarrhalis P. aeruginosa
features of K. pneumonia
seen in alcholics or smokers. greater tendency for abscess formation
features of H. influenza and M.catarrhalis
Pneumonia in elderly and patients with COPD
most common pathogen in atypical pneumonia
Mycoplasma pneumoniae
features of mycoplasma pneumoniae
skin rashes
erythema
arthritis
aseptic meningitis
note this
viral or fungal infections are uncommon immunoomptetent hosts
HAP, VAP and HCAP related microorganisms
Pseudomonas aeruginosa,Klebsiella pneumoniae, Escherichia coli, Enterobacter spp, Serratia spp, Staphylococcus aureus
note they are usually drug resistant
immunocompromised patient microorg
P. jiroveci
M. tuberculosis
Norcardia spp
Asperigullus spp
features of sputum in pneumonia
Rust-coloured sputum: S tr e p t o c o c c u s p n e u m o n i a e
• Green sputum: P s e u d o m o n a s , H a e m o p h il u s , and Pneumococcal species
• Red currant-jelly sputum: K l e b si e ll a species • Foul-smelling sputum: Anaerobic infections
what about cough in atypical pneumonia
prolonged dry cough
presence of rigors
pneumococcal pneumonia
Atypical pneumonia
In atypical pneumonia, constitutional symptoms such as headache, low-grade fever, malaise often predominate over respiratory symptoms
Aspiration risks
Alcoholism altered mental status dysphagia GERD seizure
comorbid conditions
asthma COPD HIV DM smoking
Chest examination findings
Reduced chest expansion, Increased tactile fremitus • Dullness to percussion • Decreased intensity of breath sounds, Bronchial breath sounds, Coarse inspiratory crackles, Whispering pectoriloquy, bronchophony or egophony, Pleural friction rub • Increased vocal resonance
gold standard investigation
chest xray
two widely used clinical prediction rules to admission and triage decisions
PSI - Pneumonia severity index
CURB-65
CURB65
Confusion – Altered mental status • Urea – BUN level greater than 7mmol/L • Respiratory rate – greater than 30 breaths per minute • BP – Systolic pressure < 90 mm Hg or diastolic pressure < 60 mm Hg • Age 65 years or more
interpretation of score
Score of 0-1 – Outpatient treatment
• Score of 2 – Admission to medical ward
• Score of 3 or higher – Admission to intensive care unit (ICU)
differentials for pneumonia if it’s not resolving
PTB
Sarcoidosis
malignancies
congestive heart failure
pneumonia complications
SLAP HER Septicemia lung abscess ARDS para pneumonic effusions hypotension empyema respiratory failure or renal failure
leukopenia sign of
sepsis
only chest sign in atypical pneumonia
Mild crackles
what stain for P.jiroveci
Silver stain
Legionella pneumonia: how it presents
Bradycardia, fever, diarrhea
txt - OPD
which med for previously healthy patient who hasnt taken antibiotics within the past 3 months
Macrolide(clari or azi)
txt - OPD
pt with comorbid medical conditions
respiratory fluoroquinolone - moxifloxacin
OR
a macrolide plus beta- lactam - amoxicillin clavulanate, cefuroxime
when should clinical response to antibiotuc therapy be evaluated
within 48 - 72 hours of initiation