PNEUMONIA - Disease Management

Pneumonia is an acute infection of the lung parenchyma including the alveolar spaces and interstitial tissue. It can involve the entire lobe (lobar pneumonia), a segment of a lobe (segmental or lobular pneumonia), alveoli contiguous to bronchi (bronchopneumonia), or interstitial tissue (interstitial pneumonia). These distinctions can be made based on an X-ray.

Classification

• Community-acquired (pneumonia contracted outside a health-care institution)
• Nosocomial (acquired in a hospital or other long-term health care facility).

Other types of pneumonia include:

• Aspiration pneumonia
• Atypical pneumonia
• Bacterial pneumonia
• CMV pneumonia
• Legionella pneumonia
• Mycoplasma pneumonia (walking pneumonia)
• Necrotizing pneumonia
• Pediatric pneumonia
• Pneumocystis carinii pneumonia
• Pneumonia in an immunocompromised host
• Pneumonia with lung abscess
• Pyogenic pneumonia
• Viral pneumonia.

Signs and Symptoms

• Chills
• Fever
• Cough
• Chest pain
• Labored breathing
• Fatigue
• Anorexia
• Headache
• Leucocytosis
• Bloody sputum
• Aspiration of gastric contents, water, or other irritants.

Causes

Pneumonia is not a single disease. It can have over 30 different causes. There are five main causes of pneumonia:

• Bacteria
• Viruses
• Mycoplasmas
• Other infectious agents, such as fungi - including pneumocystis
• Various chemicals

Risk Factors

• Upper respiratory tract infections
• Advanced age
• Alcoholism
• Cigarette smoking
• Institutionalization
• Malnutrition
• Immunosuppression
• Cancer
• Liver or kidney disease
• Congestive heart disease
• Cerebrovascular disease

DIAGNOSIS

Clinical examination reveals bronchial breathing, crepitations decreased breathing sounds and dullness to percussion.

Investigations

• Chest X-ray
• Gram's stain and culture of the sputum
• CBC
• Arterial blood gases
• Bacterial cultures of mucus produced by coughing
• Mantoux skin test
• Serological tests

TREATMENT

Goal

• Eradication of the microorganism involved.
• Identification and treatment of underlying precipitating factors.
• Prevention of hypoxia and hypercapnia.
• Prevention and early treatment of complications.
• Nutritional support.
• Symptomatic and supportive treatment.

Supportive therapy includes oxygen and respiratory treatments to remove secretions if needed. With treatment, most types of bacterial pneumonia can be cured within 1 to 2 weeks. Viral pneumonia may last longer. Mycoplasmal pneumonia may take 4 to 6 weeks to resolve completely.

Non-Pharmacological Treatment

Small frequent feeds are given by nasogastric tube, if necessary. IV fluids/alimentation given if enteral feeds are not tolerated

Pharmacological Treatment

Organism-Streptococcus pneumonia Pen MIC<2.0 5g/mL

1st line agents - Cephalosporins, Quinolones

2nd line agents - Vancomycin

Organism- Haemophilus influenza

1st line agents - Cephalosporins-2nd & 3rd Generation

Tetracyclines, penicillins, macrolides, Co-trimoxazole

2nd line agents Quinolones, macrolides

Organism - Moraxella catarrhalis

1st line agents Cephalosporins

2nd & 3rd generation co-cotrimoxazole, macrolides, penicillins

2nd line agents-Quinolones

Organism- Anaerobes

1st line agents Penicillins

2nd line agents - Imipenem, meropenem

Organism - Staphylococcus aureus (Methicillin-susceptible)

1st line agents - Nafcillin, oxacillin, cloxacillin, flucloxacillin w/or w/o rifampicin or gentamicin

2nd line agents - Cephalosporins

Organism-Staphylococcus aureus (Methicillin-resistant)

1st line agents Vancomycin w/ or w/o rifampicin, gentamicin

Organism- Enterobacteriaceae; Coliforms:

E Coli, Klebsiella, Proteus, and Enterobacter

1st line agents -cephalosporins

3rd Generation Cephalosporin w/or w/o aminoglycoside or imipenem or meropenem

2nd line agents- Penicillins, amoxicillin/clavulanate, ampicillin/sulbactam, quinolones

Organism- Pseudomonas aeruginosa

1st line agent- Aminoglycoside, penicillin ceftazidime, ciprofloxacin, cefepime

2nd line agents-Ciprofloxacin and Aminoglycoside or ciprofloxacin and penicillin

Organism- Legionella

1st line agents

azithromycin w or w/o rifampicin, ciprofloxacin, levofloxacin, erythromycin, clarithromycin,

2nd line agents Doxycycline w/ or w/o rifampicin

Organism- Mycoplasma pneumonia

1st line agents Tetracyclines, macrolides, quinolones

Organism- Chlamydia pneumonia

1st line agents Tetracyclines, macrolides, quinolones

Organism- Streptococcus pneumonia Pen MIC<2.0 5g/mL

1st line agents Penicillins

2nd line agents - Cephalosporins, tetracyclines, penicillins

Organism- Streptococcus pneumonia Pen MIC 2.0 5g/mL

1st line agents-Cephalosporins, quinolones

2nd line agents-Other Antibiotic: Vancomycin

Organism- Haemophilus influenza

1st line agents 2nd & 3rd Generation Cephalosporins

Tetracyclines, penicillins, macrolides

• Azithromycin

Combination Antibiotics

• Co-trimoxazole

2nd line agents-Quinolones, macrolides

Organism- Moraxella catarrhalis

1st line agents- Cephalosporins 2nd & 3rd Generation, Co-trimoxazole

2nd line agents - Quinolones

Organism- Anaerobes

1st line agents - Penicillins

Other Antibiotic: Clindamycin

2nd line agents-Other Antibiotics Imipenem, meropenem

Organism- Staphylococcus aureus (MethicillinsUsceptible)

1st line agents Nafcillin, Oxacillin, Cloxacillin,

Flucloxacillin w/or w/o Rifampicin or Gentamicin

2nd line agents Cephalosporins

• Others-Clindamycin, Co-trimoxazole

Organism- Staphylococcus aureus (Methicillin-resistant)

1st line agents-Vancomycin w/ or w/o Rifampicin, gentamicin

Organism- Enterobacteriaceae Coliforms: E Coli, Klebsiella, Proteus, and Enterobacter

1st line agents-3rd Generation Cephalosporin w/or w/o Aminoglycoside or imipenem or meropenem

2nd line agents-Aztreonam 

Penicillins, quinolones

Organism- Pseudomonas aeruginosa

1st line agents-Aminoglycoside and Ticarcillin, Piperacillin

2nd line agents-Ciprofloxacin and Aminoglycoside or Mezlocillin, Ceftazidime, Cefepime, Aztreonam Ciprofloxacin, and Ticarcillin, Piperacillin or Mezlocillin

Organism- Legionella

1st line agents Erythromycin, Clarithromycin, Azithromycin or Dirithromycin w/or w/o Rifampicin, Ciprofloxacin, Levofloxacin, Gatifloxacin or Moxifloxacin

2nd line agents Doxycycline w/or w/o Rifampicin

Organism- Mycoplasma pneumonia

1st line agents-Tetracyclines, macrolides

2nd line agents Quinolones

Organism- Chlamydia pneumonia

1st line agents Tetracyclines, macrolides

2nd line agents Quinolones

Surgical Treatment

Large or symptomatic pneumothoraces require drainage by a chest tube. Needle aspiration is used to relieve a tension pneumothorax, and followed by chest tube placement.

Empyema and most large pleural effusions require chest tube drainage. More aggressive surgical procedures such as open drainage or decortication are rarely indicated for empyema.

Complications

• Acute respiratory failure
• Death
• Empyema
• Pleuritis
• Pleural effusion
• Pneumothorax
• Bronchiectasis
• Lung abscess

Prevention

Vaccination (polyvalent pneumococcal vaccine, flu vaccine, Hib vaccine) may help prevent some types of pneumonia.

Coughing and deep breathing may help prevent some forms of nosocomial pneumonia.

Prognosis

• Most patients will respond to treatment and improve within two weeks.
• Elderly or debilitated patients who fail to respond to treatment may die from respiratory failure.