Community Acquired Pneumonia in adults- Management

Community-acquired pneumonia (CAP) refers to pneumonia that is acquired outside a hospital setting. Common causative organisms include:

• Streptococcus pneumoniae

• Haemophilus influenzae

• Moraxella catarrhalis

• Atypical bacteria:

  • Chlamydia pneumoniae

  • Mycoplasma pneumoniae

  • Legionella species

• Viral respiratory pathogens:

  • Rhinovirus

  • Influenza virus

Clinical presentation

Patients with CAP may present with:

• Fever

• Cough (dry or productive), with or without purulent sputum

• Dyspnea

• Pleuritic chest pain

• Tachypnea

• Crepitations (rales) over the affected lobe or segment

• Increased tactile fremitus

• Bronchial breath sounds (if consolidation is present)

• Decreased tactile fremitus

• Dullness to percussion over the affected area

Investigations

Laboratory Investigations

• Pulse oximetry to assess oxygen saturation

• Full Blood Count (FBC)

  • Increased white blood cell count (WBC)

  • Neutrophilia

• C-reactive protein (CRP) and/or Erythrocyte Sedimentation Rate (ESR)

  • Usually elevated in bacterial infections

• Arterial Blood Gas (ABG)

  • Assess pH and bicarbonate levels

• HIV serology (if HIV status is unknown)

• Sputum culture and sensitivity

  • Recommended for hospitalized patients and those with severe disease requiring ICU admission

• Blood cultures

  • Recommended for hospitalized patients

  • Not routinely recommended for ambulatory patients

Imaging studies

• Chest X-ray (PA and Lateral Views)

  • Focal pulmonary infiltrates

  • Consolidation

  • Pleural effusion (>5 cm)

• Bronchoscopy (when indicated)

  • Immunosuppressed patients

  • Critically ill patients

  • Failure to respond to treatment

  • Suspected tuberculosis (TB)

  • Suspected Pneumocystis pneumonia (PCP)

  • Inadequate respiratory specimens

• CT Chest Scan or High-Resolution CT (HRCT)

  • Lack of clinical improvement

  • Suspected fungal infection

  • Suspected interstitial lung disease (ILD)

  • Other complicated cases

Note:

• CT chest should not be used routinely to diagnose pneumonia.

Non-pharmacological treatment

• Encourage smoking cessation in patients who smoke

• Vaccination when indicated, preferably in a specialized center:

  • Adults aged >65 years

  • Children aged <5 years

• Ensure adequate hydration

• Encourage adequate nutrition

• Provide supplemental oxygen when indicated

• Encourage early mobilization as tolerated

• Educate patients on cough etiquette and hand hygiene to reduce transmission of respiratory infections

Pharmacological treatment

First line treatment of CAP

Table 1: First Line Treatment of Typical Community Acquired Pneumonia

Second line treatment of CAP

If no response to first line further investigation is required. If patient is in respiratory distress, or no response after 3 days of first line treatment, or patient’s condition deteriorates, then investigate, start empiric treatment while wait for culture and sensitivity

S: piperacillin + tazobactam (FDC) (IV) 4.5g 6hourly for 7days

Table2: Treatment of Typical and Atypical Community Acquired Pneumonias Organism Specific

Note

• In severe Pneumocystis jirovecii pneumonia (PCP), add 30 – 40mg prednisolone for 14days consider tapering down after recovery

• Patients with pneumonia should be afebrile for 48-72hours and have improved clinically before antibiotic therapy is stopped. The duration of therapy may need to be increased if the initial empirical therapy has no activity against the specific pathogen or if the pneumonia is complicated by extra pulmonary infection.

Alternative in Staphylococcal and Klebsiella Pneumonia:

• ceftazidime (IV/IM) 2g 8hourly for 7–14days