Bacterial Pneumonia

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Pneumonia is an infection that inflames respiratory bronchi, alveolar sacs and interstitium.

Symptoms[edit | edit source]

  • acute fever, cough, tachypnoea
  • immunocompetent patients may not seem severely ill (higher temperature, signs of toxic effect, cough - dry, later changes to productive, shortness of breath)
  • predisposition to bacterial pneumonia are immunodeficiency, congenital lung anomalies, cystic fibrosis, ciliary dysfunction...

Diagnosis[edit | edit source]

  • auscultation - bronchial breath sounds, crackles, rales, percussion dullness, increased pectoral fremitus
  • combined with pleural pathology – tight chest, shallow breathing, pain, pleural friction
  • when an effusion is present - percussion dullness, shallow or compressive breathing
  • sometimes it can manifest as abdominal pain or meningism
  • higher WCC - higher than 15× 109/l
  • chest X-ray: lobar consolidation, interstitial and air space opacification
    • when an effusion is present – opacity in lower and lateral parts of the lungs
    • it is important to make an imige of the patient lying down and on the patient's side

Differential Diagnosis[edit | edit source]

  • atelectasis (X-Ray - concave border, lobar pneumonia has convex border)
  • pleural effusion, lung, mediastinal or pleural tumors, foreign body aspiration, aspiration of gastric contents, lung infarction, lung congestion, chronic interstitial lung disease,...

Complications[edit | edit source]

  • lung abscess, empyema (staphylococci, beta-hemolytic streptococci group A)
  • meningitis, otitis media, sinusitis, pericarditis, septicemia
  • immunocompromised patients (for example splenectomy,...) - predisposition to sepsis

Therapy[edit | edit source]

  • antibiotics targeted against the agent
  • it is important to have an X-Ray, age of the patient, patient's immune status
  • pneumococcus – PNC, amoxicillin, ampicillin, erythromycin, clindamycin
    • symptoms of toxicity with breath shortness - crystal PNC i.v.
  • haemophilus influenzae – ampicillin, cephalosporins (7−10 days parenteral, 10−14 days oral),
  • staphylococcus – antistaphylococcal PNC (oxacilin, cloxacillin, methicillin), then cephalosporins and aminoglycosides
    • vancomycin for resistent staphylococcus
  • empyema – thoracentesis or chest drainage
  • oxygen therapy, rehydratation

Prognosis[edit | edit source]

  • usually good if the diagnosis and therapy is fast
  • mortality of a pneumonia without complications - lower than 1%

Prevention[edit | edit source]

  • vaccination,
  • children under 2 years, patients after splenectomy - pneumococcal vaccination

Staphylococcal Pneumonia[edit | edit source]

  • nowadays rare, more common with infants compared to older children
  • severe because of its progessive course and tendency towards complications - abscesses, pyopneumothorax
  • staphylococcus aureus - virulence factors - enzymes, toxins (hemolysin, leukocidin, staphylokinase, coagulase)
  • bronchogenic or hematic spread of the infection

Pathophysiology[edit | edit source]

  • inflammatory deposits merge, s. aureus quickly grows and destroys its surroundings, small abscesses are formed
  • rupture of a subpleural abscess creates pyopneumothorax
  • partial obstruction of small bronchi can lead to pneumatoceles' formation
  • septic thrombus can be formed in pulmonary veins

Symptoms[edit | edit source]

  • acute fever, shortness of breath
  • staphyloderma may appear
  • infants - peracute, sepsis
  • physical examination: in the early stages is the same as for pneumonia, when empyema or pyopneumothorax is formed then shallow breathing
  • laboratory tests: leukocytosis, neutrophilia, anemia, a left shift in blood count, high ESR and CRP, positive blood culture
  • chest X-Ray (lungs + heart): at first small bronchopulmonary deposits, they quickly grow and merge
    • exudate formation
    • abscesses – form cavities with with a wide border (filled with air after emptying the content into the bronchus)
  • complications: rare with targeted ATB therapy, younger infants - staphylococcal pericarditis, meningitis, osteomyelitis, metastatic abscesses

Diagnosis[edit | edit source]

  • complicated during early stages
  • anamnesis - information about staphyloderma or mother's mastitis
  • clinical symptoms, X-Ray, cultivation
  • differential diagnosis: pneumonias that could be complicated by empyema (agents: streptococci, klebsiella, haemophilus)

Therapy[edit | edit source]

  • antistaphylococcal ATB - oxacillin, vancomycin (3-4 weeks)
  • i.v. application of Ig or antistaphylococcal serum
  • empyema – chest drainage (max. 7 days)
  • prognosis – high mortality, it is influenced by the health status of the patient before the illness and by complications

Typical and Atypical Pneumonia[edit | edit source]

Basic Characteristics significant physical findings poor physical findings
Agents (extracelular)

Streptococcus pneumoniae, Haemophilus influenzae Haemophilus parainfluenzae, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli a Pseudomonas aeruginosa


Mycoplasma pneumoniae, Chlamydophila pneumoniae, Chlamydophila psittaci, Legionella pneumophila Coxiella burnetii, viruses – RSV, influenza, Pneumocystis carinii

Disease Onset acute after an upper respiratory tract infection, slow
Extrapulmonary Symptoms mild common - headaches, myalgias, vomiting, diarrhea
Fever septic fever higher temperature
Shivering yes rare
Cough productive dry
Heart Rate tachycardia is possible normal
Patient looks ill "okay, fine"
Physical Examination crepitus, bronchial breath sounds, rales rarely rales
X-Ray segmental/lobar opacification (alveoli defect) reticulonodular interstitial pattern (interstitial defect)
ESR high sligthly increased
Inflammatory Markers high slightly increased
Blood Test leukocytosis lymphocytosis
Therapy penicillins macrolides

Reference[edit | edit source]

  • BENEŠ, Jiří. Studijní materiály [online]. [cit. 2010]. <>.