Light’s Criteria

Other Known Aliasesnone

Definitionset of laboratory findings in pleural effusions that helps differentiate the fluid as transudative or exudative

Clinical Significance after performing a diagnostic thoracentesis, the fluid can be sent to the lab for biochemical analysis. The results of this analysis can tell the medical team the whether the fluid is transudative or exudative, which can narrow down the causes and provide a diagnostic schema for management.

HistoryNamed after Richard W. Light, a practicing pulmonologist from Vanderbilt University in Nashville, TN. He received his medical doctorate from Johns Hopkins University in 1968 and completed his residency and fellowship there in 1972. He would spend the next 20 years at UC-Irvine building his international reputation as an expert on pleural diseases. He is the author and editor for 16 current textbooks, including the gold standard textbooks Pleural Diseases and The Textbook of Pleural Diseases, as well as authored more than 450 peer reviewed articles. His eponymous criteria were first introduced in 1972 in an article he published as a fellow in the Annals of Internal Medicine….his very first paper as a physician.


  1. Firkin BG and Whitwirth JA.  Dictionary of Medical Eponyms. 2nd ed.  New York, NY; Parthenon Publishing Group. 1996.
  2. Bartolucci S, Forbis P.  Stedman’s Medical Eponyms.  2nd ed.  Baltimore, MD; LWW.  2005.
  3. Yee AJ, Pfiffner P. (2012).  Medical Eponyms (Version 1.4.2) [Mobile Application Software].  Retrieved http://itunes.apple.com.
  4. Whonamedit – dictionary of medical eponyms. http://www.whonamedit.com
  5. Up To Date. www.uptodate.com
  6. Light RW, Macgregor MI, Luchsinger PC, Ball WC Jr. Pleural effusions: the diagnostic separation of transudates and exudates. Ann Intern Med. 1972; 77(4):507-13. [pubmed]
  7. Biography of Richard Light. https://respiratory.annualcongress.com/ocm/2019/richard-w-light-vanderbilt-university-nashville
  8. Newman JH. Giants in chest medicine: Richard W. Light, MD. Chest. 2014; 146(5):1152-1154. [pubmed]

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