Pleural effusion Chest x-ray of a pleural effusion. The arrow A shows fluid layering in the right pleural cavity. The B arrow shows the normal width of the lung in the cavity

Pleural effusion is excess fluid that accumulates in the pleural cavity, the fluid-filled space that surrounds the lungs. The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) is a coding of diseases and signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or diseases, as classified by the World Health Organization (WHO). ... // J00-J99 - Diseases of the respiratory system (J00-J06) Acute upper respiratory infections (J00) Acute nasopharyngitis (common cold) (J01) Acute sinusitis (J02) Acute pharyngitis (J03) Acute tonsillitis (J04) Acute laryngitis and tracheitis (J05) Acute obstructive laryngitis (croup) and epiglottitis (J050) Acute obstructive laryngitis (croup) (J051) Acute epiglottitis (J06) Acute upper... // J00-J99 - Diseases of the respiratory system (J00-J06) Acute upper respiratory infections (J00) Acute nasopharyngitis (common cold) (J01) Acute sinusitis (J02) Acute pharyngitis (J03) Acute tonsillitis (J04) Acute laryngitis and tracheitis (J05) Acute obstructive laryngitis (croup) and epiglottitis (J050) Acute obstructive laryngitis (croup) (J051) Acute epiglottitis (J06) Acute upper... The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... ImageMetadata File history File links Pleural_effusion. ... ImageMetadata File history File links Pleural_effusion. ... The lungs are surrounded by two membranes, the pleurae. ... Human respiratory system The lungs flank the heart and great vessels in the chest cavity. ...

Four types of fluids can accumulate in the pleural space:

• Serous fluid (hydrothorax)
• Blood (hemothorax)
• Chyle (chylothorax)
• Pus (pyothorax or empyema)

In physiology, the term serous fluid is used for various bodily fluids that are typically pale yellow and transparent, and of a benign nature. ... A hydrothorax is a condition that results from fluid accumulating in the pleural cavity. ... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... A hemothorax is a condition that results from blood accumulating in the pleural cavity. ... Chyle is a milky fluid (bodily fluid) consisting of lymph and emulsified fats, or free fatty acids (FFAs). ... A chylothorax is a condition that results from lymphatic fluid accumulating in the pleural cavity. ... For the UK punk rock band, see P*U*S. PUS is also the IATA code for Gimhae International Airport. ... An empyema is a collection of pus within a natural body cavity. ...

Pathophysiology

Healthy individuals have less than 15 ml of fluid in each pleural space. Normally, fluid enters the pleural space from the capillaries in the parietal pleura, from interstitial spaces of the lung via the visceral pleura, or from the peritoneal cavity through small holes in the diaphragm. This fluid is normally removed by lymphatics in the visceral pleura, which have the capacity to absorb 20 times more fluid than is normally formed. When this capacity is overwhelmed, either through excess formation or decreased lymphatic absorption, a pleural effusion develops. The word capillary is used to describe any very narrow tube or channel through which a fluid can pass. ... The lungs are surrounded by two membranes, the pleurae. ... The lungs are surrounded by two membranes, the pleurae. ... In higher vertebrates, the peritoneum is the membrane that forms the lining of the abdominal cavity - it covers most of the intra-abdominal organs. ... In the anatomy of mammals, the diaphragm is a shelf of muscle extending across the bottom of the ribcage. ... Lymph originates as blood plasma lost from the circulatory system, which leaks out into the surrounding tissues. ...

Diagnosis

Pleural effusion is usually diagnosed on the basis of history and physical exam, and confirmed by chest x-ray. Chest films acquired in the lateral decubitus position (with the patient lying on their side) are more sensitive, and can pick up as little as 50 ml of fluid. At least 300 ml of fluid must be present before upright chest films can pick up signs of pleural effusion (e.g., blunted costophrenic angles). Once accumulated fluid is more than 500 ml, there are usually detectable clinical signs in the patient, such as decreased movement of the chest on the affected side, dullness to percussion over the fluid, diminished breath sounds on the affected side, decreased vocal fremitus and resonance, pleural friction rub, and egophony. In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz... Frontal chest X-ray. ... == Fremitus: Medical Term and Christian Outreach== Medical Term and a Christian Outreach Fremitus is a palpable vibration on the human body. ... Increased resonance of voice sounds, with a high-pitched nasal or bleating quality, heard especially over lung tissue that is compressed or consolidated by pleural effusion. ...

CT scan of chest showing left sided pleural effusion. Effusion fluid often settles at the lowest space due to gravity; here at the back as the patient is lying under scanner.

Once a pleural effusion is diagnosed, the cause must be determined. Pleural fluid is drawn out of the pleural space in a process called thoracentesis. A needle is inserted through the back of the chest wall into the pleural space. The fluid may then be evaluated for the following: Image File history File links Size of this preview: 800 × 478 pixelsFull resolution (838 × 501 pixel, file size: 48 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... Image File history File links Size of this preview: 800 × 478 pixelsFull resolution (838 × 501 pixel, file size: 48 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... negron305 Cat scan redirects here. ... Gravity is a force of attraction that acts between bodies that have mass. ... Thoracentesis (also known as thoracocentesis or pleural tap) is an invasive procedure to remove fluid or air from the pleural space for diagnostic or therapeutic purposes. ...

1. Chemical composition including protein, lactate dehydrogenase (LDH), albumin, amylase, pH and glucose
2. Gram stain and culture to identify possible bacterial infections
3. Cell count and differential
4. Cytology to identify cancer cells, but may also identify some infective organisms
5. Other tests as suggested by the clinical situation - lipids, fungal culture, viral culture, specific immunoglobulins

A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Lactate dehydrogenase (LDH) is an enzyme (EC 1. ... You may be looking for albumen, or egg white. ... Amylase is the name given to glycoside hydrolase enzymes that break down starch into glucose molecules. ... For other uses, see PH (disambiguation). ... Glucose (Glc), a monosaccharide (or simple sugar), is an important carbohydrate in biology. ... Gram staining is a method for staining samples of bacteria that differentiates between the two main types of bacterial cell wall. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell being used to describe the smallest unit of a living organism Cells in culture, stained for keratin (red) and DNA (green) The cell is the... Cytology (also known as Cell biology) is the scientific study of cells. ... Some common lipids. ... Subkingdom/Phyla Chytridiomycota Blastocladiomycota Neocallimastigomycota Glomeromycota Zygomycota Dikarya (inc. ... This article is about biological infectious particles. ... Schematic of antibody binding to an antigen An antibody is a protein complex used by the immune system to identify and neutralize foreign objects like bacteria and viruses. ...

Transudate vs. exudate

The third step in the evaluation of pleural fluid is to determine whether the effusion is a transudate or an exudate. Transudative pleural effusions are caused by systemic factors that alter the balance of the formation and absorption of pleural fluid (e.g., left ventricular failure, pulmonary embolism, and cirrhosis), while exudative pleural effusions are caused by alterations in local factors that influence the formation and absorption of pleural fluid (e.g., bacterial pneumonia, cancer, and viral infection). Congestive heart failure (CHF), also called congestive cardiac failure (CCF) or just heart failure, is a condition that can result from any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump a sufficient amount of blood through the body. ... Cirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrotic scar tissue as well as regenerative nodules, leading to progressive loss of liver function. ... Bacterial pneumonia is an infection of the lungs by bacteria. ...

Transudative and exudative pleural effusions are differentiated by comparing chemistries in the pleural fluid to those in the blood. According to a meta-analysis, exudative pleural effusions meet at least one of the following criteria ^[1]: A meta-analysis is a statistical practice of combining the results of a number of studies. ...

1. Pleural fluid protein >2.9 g/dL (29 g/L)
2. Pleural fluid cholesterol >45 mg/dL (1.16 mmol/L)
3. Pleural fluid LDH >60 percent of upper limit for serum

Previously criteria proposed by Light for an exudative effusion are met if at least one of the following exists (Light's criteria) ^[2]:

1. The ratio of pleural fluid protein to serum protein is greater than 0.5
2. The ratio of pleural fluid LDH and serum LDH is greater than 0.6
3. Pleural fluid LDH is more than two-thirds normal upper limit for serum

Twenty-five percent of patients with transudative pleural effusions are mistakenly identified as having exudative pleural effusions by Light's criteria. Therefore, additional testing is needed if a patient identified as having an exudative pleural effusion appears clinically to have a condition that produces a transudative effusion. In such cases albumin levels in blood and pleural fluid are measured. If the difference between the albumin levels in the blood and the pleural fluid is greater than 1.2 g/dL (12 g/L), it can be assumed that the patient has a transudative pleural effusion. You may be looking for albumen, or egg white. ...

If the fluid is definitively identified as exudative, additional testing is necessary to determine the local factors causing the exudate.

Exudative pleural effusions

Once identified as exudative, additional evaluation is needed to determine the cause of the excess fluid, and pleural fluid amylase, glucose, and cell counts are obtained. The fluid is also sent for Gram staining and culture, and, if suspicious for tuberculosis, examination for TB markers (adenosine deaminase > 45 IU/L, interferon gamma > 140 pg/mL, or positive polymerase chain reaction (PCR) for tuberculous DNA). Adenosine deaminase (sometimes known as ADA) is an enzyme in the purine metabolism. ... Interferon-gamma or IFN-g is a dimerized soluble cytokine which is a Type II Interferon. ... “PCR” redirects here. ...

Pleural fluid amylase is elevated in cases of esophageal rupture, pancreatic pleural effusion, or cancer. Glucose is decreased with cancer, bacterial infections, or rheumatoid pleuritis. If cancer is suspected, the pleural fluid is sent for cytology. If cytology is negative, and cancer is still suspected, either a thoracoscopy, or needle biopsy of the pleura may be performed. A pancreatic fistula is an abnormal communication between the pancreas (actually pancreatic duct) and the exterior of the body via the abdominal wall. ... Rheumatoid pleuritis, a form of pleural effusion, is an uncommon complication of rheumatoid arthritis, occurring in 2-3% of patients (Walker and Wright, 1967; Naylor, 1990) // Histopathology Light microscopy reveals replacement of normal cells lining the pleura (mesothelial cells) by a layer of pseudostratified epithelioid cells, multinucleated giant macrophages, and... Thoracoscopy is a medical procedure involving internal inspection of the pleural cavity. ...

Causes

The most common causes of transudative pleural effusions in the United States are left ventricular failure, pulmonary embolism, and cirrhosis (causing hepatic hydrothorax), while the most common causes of exudative pleural effusions are bacterial pneumonia, cancer (with lung cancer, breast cancer, and lymphoma causing approximately 75% of all malignant pleural effusions), viral infection, and pulmonary embolism. Although pulmonary embolism can produce either transudative or exudative pleural effusions, the latter is more common. Congestive heart failure (CHF), also called congestive cardiac failure (CCF) or just heart failure, is a condition that can result from any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump a sufficient amount of blood through the body. ... Cirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrotic scar tissue as well as regenerative nodules, leading to progressive loss of liver function. ... This article is about human pneumonia. ... Lung cancer is the malignant transformation and expansion of lung tissue, and is the most lethal of all cancers worldwide, responsible for 1. ... Breast cancer is cancer of breast tissue. ... This article is about lymphoma in humans. ...

Other causes of pleural effusion include, tuberculosis (though pleural fluid smears are rarely positive for AFB, this is the most common cause of pleural effusion in some developing countries), autoimmune disease such as systemic lupus erythematosus, bleeding (often due to chest trauma), chylothorax (most commonly caused by trauma), and accidental infusion of fluids. Less common causes include, esophageal rupture or pancreatic disease, intraabdominal abscess, rheumatoid arthritis, asbestos pleural effusion, Meig's syndrome (ascites and pleural effusion due to a benign ovarian tumor), and ovarian hyperstimulation syndrome. Tuberculosis (abbreviated as TB for tubercle bacillus or Tuberculosis) is a common and deadly infectious disease caused by mycobacteria, mainly Mycobacterium tuberculosis. ... Rheumatoid arthritis (RA) is traditionally considered a chronic, inflammatory autoimmune disorder that causes the immune system to attack the joints. ... Meigs syndrome is the triad of ovarian fibroma (a benign tumor of the ovary), ascites, and right hydrothorax, first described in 1936 by Meigs and Cass. ... Ovarian hyperstimulation syndrome (OHSS) is a complication from some forms of fertility medication. ...

Pleural effusions may also occur through medical/surgical interventions, including the use of medications (pleural fluid is usually eosinophilic), coronary artery bypass surgery, abdominal surgery, endoscopic variceal sclerotherapy, radiation therapy, liver or lung transplantation, and intra- or extravascular insertion of central lines. Eosinophilic is a technical term used by histologists. ... Early in a coronary artery bypass surgery during vein harvesting from the legs (left of image) and the establishment of bypass (placement of the aortic cannula) (bottom of image). ... Varian Clinac 2100C Linear Accelerator Radiation therapy (or radiotherapy) is the medical use of ionizing radiation as part of cancer treatment to control malignant cells (not to be confused with radiology, the use of radiation in medical imaging and diagnosis). ...

Treatment

Treatment depends on the underlying cause of the pleural effusion. Therapeutic aspiration may be sufficient; larger effusions may require insertion of an intercostal drain (either pigtail or surgical). Repeated effusions may require chemical (talc, bleomycin, tetracycline/doxycycline) or surgical pleurodesis, in which the two pleural surfaces are attached to each other so that no fluid can accumulate between them. Pleurodesis is the artificial obliteration of the pleural space. ...

See also

• Empyema
• Heart failure
• Pulmonary embolism
• Thoracentesis

An empyema is a collection of pus within a natural body cavity. ... Thoracentesis (also known as thoracocentesis or pleural tap) is an invasive procedure to remove fluid or air from the pleural space for diagnostic or therapeutic purposes. ...

External links

• Medline Plus Article on Pleural Effusion
• Pleural Effusion Virtual Cancer Centre
• Pleural Effusion Images from MedPix

References

1. ^ Heffner J, Brown L, Barbieri C (1997). "Diagnostic value of tests that discriminate between exudative and transudative pleural effusions. Primary Study Investigators". Chest 111 (4): 970-80. PMID 9106577. 
2. ^ Light R, Macgregor M, Luchsinger P, Ball W (1972). "Pleural effusions: the diagnostic separation of transudates and exudates". Ann Intern Med 77 (4): 507-13. PMID 4642731. 

• Light RW (2001). Pleural Diseases, 4th ed., New York: Lippincott Williams & Wilkins.  ISBN 0-7817-2777-4
• Light RW (2005). "Chapter 245: Disorders of the pleura, mediastinum, diaphragm, and chest wall", in Kasper DL, Braunwald E, Fauci A, Hauser S, Longo D, Jameson JL: Harrison's Principles of Internal Medicine, 16th ed., New York, NY: McGraw-Hill Professional.  ISBN 0-07-140235-7
• Dowdeswell IRG (1998). "Chapter 64: Pleural Diseases", in Stein JH: Internal Medicine, 5th ed., New York: C.V.Mosby.  ISBN 0-8151-8698-3