14- pneumonia pt.2

• Complications of pneumonia

  • Abscess
  • Pleural effusion
  • Empyema
  • Septicemia
• Differential diagnosis of pneumonia

  • PE
  • Pulmonary edema or hemorrhage
  • Bronchial carcinoma
  • Hypersensitivity pneumonitis
  • Diffuse parenchymal lung disease with acute onset
• Investigations for pneumonia

  • Chest x-ray: Confirms area of consolidation, Must repeated after 6 weeks (to check for underlying lung malignancy)
  • Sputum: Gram stain, Culture and sensitivity
  • CBC: WBC more than 15*109 suggests bacterial origin, Lymphopenia associated with legionella
  • Specific etiology: Urine for legionella and pneumococcal antigens, Cold agglutinins in mycoplasma pneumonia, Serology (mycoplasma: raised IgM)
  • ABG: Done if SpO2 < 92% or rising PaCO2
• Infecting agents and clinical circumstances

  • Streptococcus pneumonia, Mycoplasma pneumonia, Influenza A, Chlamydia pneumonia - Community acquired and usually previously fit
  • Hemophilus influenza - COPD
  • Chlamydia psittaci - Contact with birds
  • Staphylococcus aureus - Children, IV drug abusers, complicated influenza virus infections
  • Legionella pneumophila - Hospitals and hotels (institutional outbreaks)
  • Coxiella burnetti - Animal-hide workers
  • Pseudomonas aeruginosa - Cystic fibrosis and bronchiectasis
  • Enteric gram-negative bacilli - Acutely ill
  • Pneumocystis jiroveci, Nocardia asteroids, Cytomegalovirus, Aspergillus fumigatus - Immunocompromised (AIDS, lymphoma, leukemias, use of cytotoxic drugs and corticosteroids)
• CURB-65 scoring system

  1 point for each: Confusion, Urea>7mmol, Respiratory rate > 30/min, BP < 90 systolic / 60 diastolic, Age > 65
• Management

  1. 0-1 score: Low risk à oral antibiotics/ home treatment

  2. ≥ 3 score: Severe pneumonia (à admit to ICU esp. if 4 or 5)
• Severe pneumonia management

  • Analgesia for pleuritic pain
  • Humidified oxygen if hypoxemic
  • IV Fluids
• Antibiotic therapy for CAP - Outpatient treatment

  1. Macrolide (clarithromycin) à covers S. pneumo and atypical organisms

  2. If resistance is suspected à supplement with B-lactam (amoxicillin)

  3. Outpatient Tx is used when CURB score 0-1

  4. Duration of Tx: 1 week to 10 days

  5. Review Tx if still febrile within 72 hours
• Risk factors for drug resistance

  • Age more than 65
  • Comorbidities
  • Immunosuppressive drug or disease
  • B-lactam, fluroquinolone, or macrolide therapy in the last 3-6 months
• Antibiotic therapy for CAP - Inpatient

  1. Macrolide + Ceftriaxone (anti-pneumococcal B-lactam)

  2. OR respiratory fluroquinolones (levofloxacin or moxifloxacin)
• Antibiotic therapy for Pseudomonal risk

  Fluroquinolone (cipro or dose levo) + one of the following: Piperacillin/tazobactam, Imipenem or meropenem, Cefepime
• Antibiotic therapy for MRSA risk

  Vancomycin or linezolid
• Influenza treatment started only if it is confirmed
• Metronidazole in patients with risk of anaerobic infection, e.g. Prolonged ICU stay or aspiration pneumonia
• Rules before stopping antibiotics

  1. Patient afebrile 48-72 hours

  2. Breathing without supplemental oxygen

  3. No more than 1 clinical instability factor (HR > 100, RR > 24, SBP ≤ 90)