Complicated Pneumonia – Parapneumonic Effusion

“Something seems a bit abnormal here…”


Back on November 12, 2010 we discussed Community Acquired Pneumonia, and naturally, we are all masters at its management now (PS, I greatly appreciate those of you who have been actually reading these weekly since 2010).  But, on occasion, the patient’s disease decides to not follow our plan.
Imagine that a patient was just evaluated within the past 48 hours in your ED or office, diagnosed with a pneumonia, and now returns because fever persists… do you (a) admit just because the kid has returned within 72 hours, (b) change antibiotics, (c) reassure the family that all is well, or (d) consider that either the initial diagnosis was not accurate or that the condition has become complicated?  Naturally, the question isn’t completely fair… as you need to be able to examine the child, but that being said, I like “d” also.

Parapneumonic Effusion

  • Do develop in normal hosts occasionally.  Children do tolerate them better than their adult conterparts.
  • Pleural Space Infection
    • Usually contains small amount of fluid, managed by lymphatic drainage system.
    • Adjacent infection can lead to inflammation, increased vascular permeability, and disturbance in pleural fluid drainage.
    • Inflammatory cells and bacteria can leak enter the pleural space leading to the pleural fluid to become infected.
    • Pro-inflammatory modulators (remember cytokines?) play a role and the activation of the coagulation cascade along with disruption to the fibrinolytic system leading to fibrin deposition.
    • All of this generates a spectrum of disease:
      • Uncomplicated Pleural Effusion – inflammatory process due to adjacent infected lung parenchyma
      • Complicated Pleural Effusion (Empyema) – bacteria invasion into the pleural space and fluid.
        • Fibrinopurulent – frank pus and potential for loculated areas.
        • Organized – fibroblast proliferation leading to thick exudate, sediment, and thick peel.  The lung can become entrapped.


  • Presentation
    • May appear similar to uncomplicated pneumonia (again, kids are tough, so be vigilant!).
    • Common to see persistent fever despite 48 hours of antibiotics.
    • May have increased work of breathing, diminished BS, dullness to percussion (as the fluid becomes organized and “liver-like”).
    • Child may choose to lie on the affected side to help with aeration to the good lung and decrease pain.


  • Diagnosis
    • CXR – naturally.  Even if two days ago the CXR was “unexciting”… for the child who returns with persistent fever, or has any increased work of breathing, or your intuition tells you to worry… check another CXR.
    • U/S – Occasionally, the CXR may be difficult to interpret, as there is too much infiltrate, so use an U/S to help define what is going on.
    • CT – not generally needed initially in the work-up of the pleural effusion.  If the fluid analysis warrants consideration for malignant etiology, than yes, get a CT. If surgery is going to be performed, then most surgeons will want to see what’s going on in there.


  • Management
    • This is still being debated and the management will vary based on your specialists practice patterns.
    • Uncomplicated Parapneumonic Effusions, often resolve with antibiotic therapy alone.
    • All others will require drainage of the pleural fluid.
    • As the fluid becomes more organized, simple thoracentesis may be inadequate.
    • Some propose drainage augmented with fibrinolytics
    • Some patients will require surgical drainage (either VATS, semi-open, or open procedures).
    • IV antibiotics to cover for Strep and Staph (and consider MRSA).
    • See (bottom of page) for a great video.


Buckingham SC, King MD, Miller ML. Incidence and etiologies of complicated parapneumonic effusions in children, 1996 to 2001. Pediatr Infect Dis J, 2003: 22: 499-504.

Strachan RE, et al. Paediatric Empyema Thoracis: Recommendations for Management. Position statement from the thoracic Society of Australia and New Zealand.

Sean M. Fox
Sean M. Fox

I enjoy taking care of patients and I finding it endlessly rewarding to help train others to do the same. I trained at the Combined Emergency Medicine and Pediatrics residency program at University of Maryland, where I had the tremendous fortune of learning from world renowned educators and clinicians. Now I have the unbelievable honor of working with an unbelievably gifted group of practitioners at Carolinas Medical Center. I strive every day to inspire my residents as much as they inspire me.

Articles: 583


  1. After looking at a number of the blog posts on your web page, I truly like your way of writing
    a blog. I saved it to my bookmark webpage list and will be checking
    back in the near future. Please check out my web site as well and let me know what you think.

Comments are closed.