Medscape is available in 5 Language Editions – Choose your Edition here.


Parapneumonic Pleural Effusions and Empyema Thoracis Clinical Presentation

  • Author: Atikun Limsukon, MD; Chief Editor: Ryland P Byrd, Jr, MD  more...
Updated: Mar 12, 2014


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.


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.



See Background for details on the etiology and bacteriology of these pleural infections.

  • Pneumonia is the leading cause of parapneumonic effusions and empyema thoracis.
  • Increasingly, empyema is also a complication of previous cardiothoracic surgery, which accounts for 30% of cases. The usual organisms are Staphylococcus species and Gram-negative bacteria.
  • Trauma can also lead to inoculation and superinfection of the pleural space.
  • In the absence of trauma or surgery, the infecting organism may have spread from blood or other organs into the pleural space. These causes include extension of infections from adjacent or distant sites (eg, ruptured esophagus, mediastinitis, osteomyelitis, pericarditis, cholangitis, diverticulitis, pericarditis) or subdiaphragmatic abscesses.
Contributor Information and Disclosures

Atikun Limsukon, MD Instructor, Department of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Thailand

Disclosure: Nothing to disclose.


Guy W Soo Hoo, MD, MPH Clinical Professor of Medicine, University of California, Los Angeles, David Geffen School of Medicine; Director, Medical Intensive Care Unit, Pulmonary and Critical Care Section, West Los Angeles Healthcare Center, Veteran Affairs Greater Los Angeles Healthcare System

Guy W Soo Hoo, MD, MPH is a member of the following medical societies: American College of Chest Physicians, American College of Physicians, American Thoracic Society, Society of Critical Care Medicine, California Thoracic Society, American Association for Respiratory Care

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Chief Editor

Ryland P Byrd, Jr, MD Professor of Medicine, Division of Pulmonary Disease and Critical Care Medicine, James H Quillen College of Medicine, East Tennessee State University

Ryland P Byrd, Jr, MD is a member of the following medical societies: American College of Chest Physicians, American Thoracic Society

Disclosure: Nothing to disclose.

Additional Contributors

Michael Peterson, MD Chief of Medicine, Vice-Chair of Medicine, University of California, San Francisco, School of Medicine; Endowed Professor of Medicine, University of California, San Francisco-Fresno, School of Medicine

Michael Peterson, MD is a member of the following medical societies: American College of Chest Physicians, American College of Physicians, American Thoracic Society

Disclosure: Nothing to disclose.


The authors and editors of Medscape Reference gratefully acknowledge the contributions of previous author, Sat Sharma, MD, FRCPC, to the development and writing of this article.

  1. Sahn SA. Diagnosis and management of parapneumonic effusions and empyema. Clin Infect Dis. 2007 Dec 1. 45(11):1480-6. [Medline].

  2. Ahmed RA, Marrie TJ, Huang JQ. Thoracic empyema in patients with community-acquired pneumonia. Am J Med. 2006 Oct. 119(10):877-83. [Medline].

  3. Tsang KY, Leung WS, Chan VL, Lin AW, Chu CM. Complicated parapneumonic effusion and empyema thoracis: microbiology and predictors of adverse outcomes. Hong Kong Med J. 2007 Jun. 13(3):178-86. [Medline].

  4. Jerng JS, Hsueh PR, Teng LJ, Lee LN, Yang PC, Luh KT. Empyema thoracis and lung abscess caused by viridans streptococci. Am J Respir Crit Care Med. 1997 Nov. 156(5):1508-14. [Medline].

  5. Bartlett JG, Gorbach SL, Thadepalli H, Finegold SM. Bacteriology of empyema. Lancet. 1974 Mar 2. 1(7853):338-40. [Medline].

  6. Grijalva CG, Zhu Y, Pekka Nuorti J, Griffin MR. Emergence of parapneumonic empyema in the USA. Thorax. 2011 Aug. 66(8):663-8. [Medline].

  7. Chalmers JD, Singanayagam A, Murray MP, Scally C, Fawzi A, Hill AT. Risk factors for complicated parapneumonic effusion and empyema on presentation to hospital with community-acquired pneumonia. Thorax. 2009 Jul. 64(7):592-7. [Medline].

  8. [Guideline] Colice GL, Curtis A, Deslauriers J, et al. Medical and surgical treatment of parapneumonic effusions : an evidence-based guideline. Chest. 2000 Oct. 118(4):1158-71. [Medline].

  9. [Guideline] Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis. 2007 Mar 1. 44 Suppl 2:S27-72. [Medline].

  10. [Guideline] Infectious Diseases Society of America/American Thoracic Society. Guidelines for the management of adults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia. Am J Respir Crit Care Med. 2005 Feb 15. 171(4):388-416. [Medline].

  11. Davies CW, Lok S, Davies RJ. The systemic fibrinolytic activity of intrapleural streptokinase. Am J Respir Crit Care Med. 1998 Jan. 157(1):328-30. [Medline].

  12. Davies RJ, Traill ZC, Gleeson FV. Randomised controlled trial of intrapleural streptokinase in community acquired pleural infection. Thorax. 1997 May. 52(5):416-21. [Medline].

  13. Bouros D, Schiza S, Tzanakis N, Chalkiadakis G, Drositis J, Siafakas N. Intrapleural urokinase versus normal saline in the treatment of complicated parapneumonic effusions and empyema. A randomized, double-blind study. Am J Respir Crit Care Med. 1999 Jan. 159(1):37-42. [Medline].

  14. Diacon AH, Theron J, Schuurmans MM, Van de Wal BW, Bolliger CT. Intrapleural streptokinase for empyema and complicated parapneumonic effusions. Am J Respir Crit Care Med. 2004 Jul 1. 170(1):49-53. [Medline].

  15. Maskell NA, Davies CW, Nunn AJ, Hedley EL, Gleeson FV, Miller R. U.K. Controlled trial of intrapleural streptokinase for pleural infection. N Engl J Med. 2005 Mar 3. 352(9):865-74. [Medline].

  16. Tokuda Y, Matsushima D, Stein GH, Miyagi S. Intrapleural fibrinolytic agents for empyema and complicated parapneumonic effusions: a meta-analysis. Chest. 2006 Mar. 129(3):783-90. [Medline].

  17. Froudarakis ME, Kouliatsis G, Steiropoulos P, et al. Recombinant tissue plasminogen activator in the treatment of pleural infections in adults. Respir Med. 2008 Dec. 102(12):1694-700. [Medline].

  18. Levinson GM, Pennington DW. Intrapleural fibrinolytics combined with image-guided chest tube drainage for pleural infection. Mayo Clin Proc. 2007 Apr. 82(4):407-13. [Medline].

  19. Cameron R, Davies HR. Intra-pleural fibrinolytic therapy versus conservative management in the treatment of adult parapneumonic effusions and empyema. Cochrane Database Syst Rev. 2008 Apr 16. CD002312. [Medline].

  20. Rahman NM, Maskell NA, West A, et al. Intrapleural use of tissue plasminogen activator and DNase in pleural infection. N Engl J Med. 2011 Aug 11. 365(6):518-26. [Medline].

  21. Janda S, Swiston J. Intrapleural fibrinolytic therapy for treatment of adult parapneumonic effusions and empyemas: a systematic review and meta-analysis. Chest. 2012 Aug. 142(2):401-11. [Medline].

  22. Abu-Daff S, Maziak DE, Alshehab D, et al. Intrapleural fibrinolytic therapy (IPFT) in loculated pleural effusions--analysis of predictors for failure of therapy and bleeding: a cohort study. BMJ Open. 2013. 3(2):[Medline]. [Full Text].

  23. Luh SP, Chou MC, Wang LS, Chen JY, Tsai TP. Video-assisted thoracoscopic surgery in the treatment of complicated parapneumonic effusions or empyemas: outcome of 234 patients. Chest. Apr/2005. 127:1427-32. [Medline].

  24. Hope WW, Bolton WD, Stephenson JE. The utility and timing of surgical intervention for parapneumonic empyema in the era of video-assisted thoracoscopy. Am Surg. 2005 Jun. 71(6):512-4. [Medline].

  25. Casali C, Storelli ES, Di Prima E, Morandi U. Long-term functional results after surgical treatment of parapneumonic thoracic empyema. Interact Cardiovasc Thorac Surg. 2009 Jul. 9(1):74-8. [Medline].

  26. Potaris K, Mihos P, Gakidis I, Chatziantoniou C. Video-thoracoscopic and open surgical management of thoracic empyema. Surg Infect (Larchmt). 2007 Oct. 8(5):511-7. [Medline].

  27. Chan DT, Sihoe AD, Chan S, et al. Surgical treatment for empyema thoracis: is video-assisted thoracic surgery "better" than thoracotomy?. Ann Thorac Surg. 2007 Jul. 84(1):225-31. [Medline].

  28. Wang ZT, Wang LM, Li S, Jian H. Electronic endoscope insertion into a thoracic drainage tube is a new technique in the treatment and diagnosis of pleural diseases. Surg Endosc. 2009 Jul. 23(7):1671-3. [Medline].

  29. St Peter SD, Tsao K, Harrison C, et al. Thoracoscopic decortication vs tube thoracostomy with fibrinolysis for empyema in children: a prospective, randomized trial. J Pediatr Surg. 2009 Jan. 44(1):106-11; discussion 111. [Medline].

  30. Ng CS, Wan S, Lee TW, Wan IY, Arifi AA, Yim AP. Post-pneumonectomy empyema: current management strategies. ANZ J Surg. 2005 Jul. 75(7):597-602. [Medline].

  31. Heffner JE, Brown LK, Barbieri C, DeLeo JM. Pleural fluid chemical analysis in parapneumonic effusions. A meta-analysis. Am J Respir Crit Care Med. 1995 Jun. 151(6):1700-8. [Medline].

Left pleural effusion developed 4 days after antibiotic treatment for pneumococcal pneumonia. Patient developed fever, left-sided chest pain, and increasing dyspnea. During thoracentesis, purulent pleural fluid was removed, and the Gram stain showed gram-positive diplococci. The culture confirmed this to be Streptococcus pneumoniae.
Left lateral chest radiograph shows a large, left pleural effusion.
A right lateral decubitus chest radiograph shows a free-flowing pleural effusion, which should be sampled with thoracentesis for pH determination, Gram stain, and culture.
CT scan of thorax shows loculated pleural effusion on left and contrast enhancement of visceral pleura, indicating the etiology is likely an empyema.
Chest CT scan with intravenous contrast in a patient with mixed Streptococcus milleri and anaerobic empyema following aspiration pneumonia, showing a thickened contrast-enhanced pleural rind, high-density pleural effusion, loculation, and septation. Thoracentesis yielded foul-smelling pus.
Chest CT scan with intravenous contrast in a patient with mixed Streptococcus milleri and anaerobic empyema following aspiration pneumonia, 3 days following thoracostomy and intrapleural fibrinolysis (Reteplase).
All material on this website is protected by copyright, Copyright © 1994-2016 by WebMD LLC. This website also contains material copyrighted by 3rd parties.