Parapneumonic Pleural Effusions and Empyema Thoracis Clinical Presentation

Updated: Nov 11, 2021
  • Author: Atikun Limsukon, MD; Chief Editor: Nader Kamangar, MD, FACP, FCCP, FCCM  more...
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Clinical manifestations of parapneumonic effusions and empyema largely depend on whether the patient has an aerobic or anaerobic infection. Aerobic infections are more acute in onset with acute febrile symptoms, while anaerobic infections can be indolent in their time course and symptoms may be nonspecific with low-grade fevers. If fever persists for more than 48 hours after the initiation of antibiotic treatment, a complicating parapneumonic effusion or empyema likely exists.

Aerobic bacterial infection

The clinical presentation in patients with aerobic bacterial pleural space infection is similar to that of patients with bacterial pneumonia. Patients present with an acute febrile illness with chest pain, sputum production, and leukocytosis. A complicated parapneumonic effusion is suggested by the presence of a fever lasting more than 48 hours after the initiation of antibiotic therapy.

Anaerobic bacterial infection

Patients with anaerobic bacterial infections involving the pleural space usually present with a subacute illness. Most of these patients have symptoms persisting for more than 7 days. Approximately 60% of patients have weight loss. Anemia is also common. Most of these patients have poor oral hygiene, many have alcoholism, or other factors that predispose them to recurrent aspiration.


Physical Examination

Most patients are febrile with tachypnea and tachycardia, often appearing toxic and fulfilling criteria for the systemic inflammatory response syndrome (SIRS). Signs of pleural effusion upon physical examination include the following:

  • Decreased or absent breath sounds

  • Dullness to percussion

  • Decreased tactile fremitus

  • Evidence of tension and contralateral tracheal shift possible with large effusions

In areas in which pneumonia and lung consolidation are adjacent and more extensive than pleural fluid, findings include (1) rales or crackles and/or (2) bronchial breath sounds or egophony.