Pneumonia Flashcards
Common causes of CAP
S pneumonia M pneumoniae Chlamydia pneumoniae Legionella Burholderia pseudomallei (tropical Aus)
Risk factors
Strong
age over 65 years HIV/immunocompromise recent respiratory infection exposure to respiratory infection recent travel high-risk occupation recent antibiotic exposure smoking comorbid medical conditions
Clinical features
Fevers Rigors Malaise Anorexia Dyspnea Cough Purulent sputum Hemoptysis Pleuritic chest pain
Initial investigations and results
CXR: infiltration, consolidation, effusion, cavitation
FBC: leukocytosis
RFTs: usually normal
Glucose: usually normal
Oximetry of ABG: hypoxemia, respiratory acidosis
Blood culture: infecting organism
Sputum culture: infecting organism
Sputum gram staining: visualising infecting organism
Secondary investigations and findings
- rapid urinary antigen tests:
positive for Legionella pneumophila, S pneumoniae, or M pneumoniae infection - pleurocentesis
exudate - serology:
rise in serum/convalescent titres, C pneumoniae, M pneumoniae, Legionella - PCR:
detection of C pneumoniae, M pneumoniae, Legionella organisms - M pneumoniae cold agglutinins:
elevated IgM titre if M pneumoniae infection - rapid viral diagnostic tests:
rapid detection of influenza A and B, parainfluenza, RSV - CT chest:
consolidation, cavitation, effusions, neoplasm - bronchoscopy:
may clarify causative organism or non-infectious aetiology
Red flags for pneumonia in adults (6)
Respiratory rate >30
BP
Assessing severity CURB-65
Confusion
Uremia
Respiratory rate >30
BP 65 yo
Criteria for severe CAP
Minor criteria:
- Respiratory rate 30 breaths/minute or greater
- PaO2/FiO2 ratio 250 or less
- Multi-lobar infiltrates
- Confusion/disorientation
- Uraemia (urea ≥20 mg/dL)
- Leukopenia (WCC
Management of pneumonia
ABC Oxygen to maintain >92% IV access Investigations Fluids Analgesia (paracetamol) + antiemetic Antibiotics Admission if required Monitor: symptoms, FBC, o2 saturation
Patient instructions
Adhere to medications Call if not improved in 72 hours \+Water intake Smoking cessation Paracetamol or aspirin Avoid cough suppressants Fatigue is common, however more rest not required
Complications
Pleural effusion Empyema Sepsis Abscess Respiratory failure Myocarditis Pericarditis Cholestasis Atrial fibrillation
Empirical therapy in CAP if outpatient
Amoxycillin or doxycicline
Inpatient moderate disease empirical CAP
Benzylpenicillin + doxycycline PO
Tropical–>
1. Risk factors present= ceftriaxone IV + Gentamicin IV as initial. Consider adding doxycycline.
Risk factors to consider with empirical therapy in tropical area (B. pseudomallei and A baumanni)
Diabetes Alcohol ++ CKD Chronic lung disease Immunosuppressive therapy
Inpatient severe disease empirical CAP
Ceftriaxone IV + azithromycin
Tropical–>
- Wet season= meropenem IV + azithromycin
- Dry season= piperacillin + tazobactam IV + azithromycin
Definition of hospital acquired pneumonia and likely organisms
Pneumonia >48 hours after admission Enterobacteria S aureus Pseudomonas Klebsiella Bacteroides Clostridia
Risk of MDR in HAP
Ward
Length
Treatment with antibiotics recently
Recurrent/prolonged admission
High level nursing
Immunosuppression
What are high risk wards
intensive care unit, high-dependency unit, or area with a high rate of MDR organisms
Length of stay in high risk ward which places person at high risk
When stay is >5 days
Treatment of HAP when lower risk of MDR organisms
Mild: amoxycillin + clavulanate PO
Moderate/severe: ceftriaxone IV
Severe: When no additional risk for MDR as above
If additional risks= treat as higher risk MDR organisms
Treatment of HAP when higher risk of MDR organisms
Piperacillin + tazobactam IV
+Vancomycin in severe sepsis/considering MRSA
+Gentamycin if severe sepsis/risk of pseudomonas/risk of gram negative
Managment following initial commencement of antibiotics in HAP
Review in 48-72 hours
Improving?
- Culture +ve direct therapy
- Culture -ve consider stopping/de-escalating
Not improving
- Consider complications
- Culture +ve direct therapy
- Repeat Ix and adjust antibiotic therapy
In what groups is S pneumonia commoner (6), clinical features, CXR findings
Elderly Alcoholics Post-splenectomy Diabetics Immunosuppressant CHD Lung disease
Lobar consolidation
Herpes labilis, fever, pleurisy
When might you sees S aureus (5), CXR
Young, elderly, complicating influenza, underlying disease
Bilateral cavitating bronchopneumonia
When does Klebsiella occur (3), CXR
Elderly, alcoholics, diabetics
Cavitating pneumonia
Mycoplasma CXR, complications
Reticular nodular pattern
STS, EM, GBS
Legionella presentation, extra-pulmonary features (7), CXR, blood test findings, urinalysis
Fever, malaise, dry cough, myalgia, dyspnea
EPF: renal failure, DV, hepatitis, anorexia, confusion
Bi-basal consolidation
Lymphopenia, hyponatremia, deranged LFTs, hematuria
How is Chlamydia psittaci acquired
From birds
Assessing pneumonia severity
Systolic BP Multi-lobar involvement Albumin low RR >25/>30 TachyC >125 Confusion (acute) Oxygen
