The undiagnosed pleural effusion

1
The undiagnosed pleural effusion

• Reporter ??? Supervisor???

2
INTRODUCTION 

• Pleural effusions can develop as a result of over
  50 different pleuropulmonary or systemic
  disorders
• The cause of a pleural effusion may not be
  evident following diagnostic thoracentesis in up
  to 25 percent of patients.

3
HISTORY The first step is to revisit the
patient's history !

• drugs, occupational exposures, risk factors for
  pulmonary embolism or tuberculosis, and comorbid
  conditions.
• nitrofurantoin, amiodarone, ovarian stimulation
  therapy
• benign asbestos pleural effusion (unilateral,
  exudative, elevated eosinophil count)
• Many systemic disorders (eg, lupus,
  hypothyroidism, amyloid) can cause an effusion
• extrapleural sources, most commonly from
  transdiaphragmatic movement. (ascites, hepatic
  and pancreatic diseases)

4
TIME COURSE Some effusions resolve spontaneously

• Time required for resolution depending upon the
  underlying etiology
• Uncomplicated parapneumonic, pulmonary embolism,
  tuberculous pleurisymay persist for several
  weeks.

5
TIME COURSE

• Malignant pleural effusions, do not resolve
  spontaneously
• Benign asbestos pleural effusion, rheumatoid
  pleurisy, and radiation pleuritis often persist
  for months to years

6
REANALYSIS OF PLEURAL FLUID

• Most undiagnosed pleural effusions are exudative
• Differential diagnosis of a transudate is limited
  and the cause can be recognized by the clinical
  presentation
• Transudate from patients receiving diuretic
  therapy may have an elevated protein level and be
  mistaken as an exudate. In such cases, if the
  total protein gradient (serum minus pleural
  fluid) is greater than 3.1g/dL, the fluid can be
  classified as a transudate.

7
TRAPPED LUNG

• A remote inflammatory process causes a fibrin
  peel to form on the visceral pleural surface,
  preventing the lung from expanding to the chest
  wall.
• In any patient with a stable chronic pleural
  effusion, particularly history of pneumonia,
  pneumothorax, thoracic surgery, or hemothorax

8
TRAPPED LUNG

• A negative pleural pressure favoring movement of
  fluid from the parietal pleural capillaries into
  the pleural space
• Diagnosed by measuring pleural pressure before
  and after thoracentesis
• (the decrease in pleural pressure is at least
  15 cm H20 per liter of fluid removed)

9
DIAGNOSTIC EVALUATION

• Imaging 
• CT of the thorax
• CT pulmonary angiography
• Positron emission tomography (PET)/CT
• Pleural biopsy
• Percutaneous
• Video assisted thoracoscopic pleural biopsy
• Open pleural biopsy

10
Imaging 

• CT of the thorax with contrast should be
  performed in virtually all patients with an
  undiagnosed pleural effusion.
• Irregular or thickened pleura with contrast
  enhancement suggests pleural inflammation or
  malignancy

11
Imaging

• CT pulmonary angiography considered if suspected
  pulmonary embolism (PE) (pleural effusion is
  common with PE)
• Focal increased uptake in the pleura on (PET)/CT
  and the presence of solid pleural abnormalities
  are suggestive of malignant.
• PET/CT may highlight extrapleural abnormalities
  that may be the cause of the effusion

12
Pleural biopsy

• Closed pleural biopsy is most useful when the
  pleural abnormality is diffuse as in tuberculous
  pleurisy
• CT guided cutting needle biopsy is useful when a
  pleural based soft tissue mass is identified by
  CT scan.
• Video assisted thoracoscopic (VATS) biopsy is
  helpful for malignant effusions, because of the
  patchy distribution on the pleural surface

13
Decision

• Whether to pursue more invasive procedures or
  simply observe requires clinical judgment that is
  guided by the patient's presentation.

14
Decision

• As an example, the patient who is over 60 years
  of age, with abnormal CT of the pleura, is more
  likely to have a malignancy as the cause of an
  undiagnosed exudate

15
Thank you very much