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Protein C and Protein S

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Also known as: Protein C Activity; Protein C Level; Protein S Activity; Protein S Level
Formal name: Protein C, Functional or Antigen; Protein S, Functional or Antigen (Free or Total)

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NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.

Sources Used in Current Review

Chen, Yi-Ben. et. al. (Updated 2013 March 3). Protein C. MedlinePlus Medical Encyclopedia. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003659.htm through http://www.nlm.nih.gov/. Accessed October 2014.

Gersten, T. et. al. (Updated 2012 February 8). Congenital protein C or S deficiency. MedlinePlus Medical Encyclopedia. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/000559.htm through http://www.nlm.nih.gov/. Accessed October 2014.

Cuker, A. and Pollak, E. (Updated 2013 March 5). Protein C Deficiency. eMedicine. Available online at http://emedicine.medscape.com/article/205470-overview through http://emedicine.medscape.com. Accessed October 2014.

(Reviewed 2013 May). Protein C deficiency. Genetics Home Reference. Available online at http://ghr.nlm.nih.gov/condition/protein-c-deficiency through http://ghr.nlm.nih.gov. Accessed October 2014.

(Reviewed 2009 October). Protein S deficiency. Genetics Home Reference.Available online at http://ghr.nlm.nih.gov/condition/protein-s-deficiency through http://ghr.nlm.nih.gov. Accessed October 2014.

(© 1995-2014) Protein S Activity, Plasma. Mayo Medical Laboratories. http://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/80775 through http://www.mayomedicallaboratories.com. Accessed October 2014.

Sadaka, F. et al. Activated protein C in septic shock: a propensity matched analysis. Critical Care 2011, 15: R89. doi:10.1186/cc10089. Available online at http://ccforum.com/content/15/2/R89 through http://ccforum.com. Accessed October 2014.

Godwin, J. (Updated 2012 January 10). Protein S Deficiency. eMedicine. Available online at http://emedicine.medscape.com/article/205582-overview through http://emedicine.medscape.com. Accessed October 2014.

Pagana, K. D. & Pagana, T. J. (© 2012). Mosby's Diagnostic and Laboratory Test Reference 11th Edition: Mosby, Inc., Saint Louis, MO. Pp 767-768.

National Blood Clot Alliance. Protein C deficiency. Available online at http://www.stoptheclot.org/News/article136.htm through http://www.stoptheclot.org. Accessed October 2014.

Sources Used in Previous Reviews

Thomas, Clayton L., Editor (1997). Taber's Cyclopedic Medical Dictionary. F.A. Davis Company, Philadelphia, PA [18th Edition].

Pagana, Kathleen D. & Pagana, Timothy J. (2001). Mosby's Diagnostic and Laboratory Test Reference 5th Edition: Mosby, Inc., Saint Louis, MO.

Gardner, B. (2001 April 3). Protein C Deficiency. Medscape Primary Care, Pediatrics Ask the Expert [Online information]. Available online at http://www.medscape.com/viewarticle/413850_print through http://www.medscape.com.

Coagulation Test Panels. Florida Hospital Cancer Institute, Clinical and Research Laboratories [Online information]. Available online at http://www.fhci-labs.com/researchlabs/clinicallabs/hemostasisandthrombosis/panels.htm through http://www.fhci-labs.com.

Confusing Coagulation Test Names. UAB Coagulation Service, Univ of Alabama at Birmingham [Online information]. Available online at http://peir.path.uab.edu/coag/article_187.shtml and Protein C Activity, Activated Protein C Resistance (Screen for Factor V Leiden) at http://peir.path.uab.edu/coag/cat_index_14.shtml#191 through http://peir.path.uab.edu.

Schlesinger, K. and Ragni, M. (2002). DIC, Inflammation, Sepsis And Activated Protein C (APC). Transfusion Medicine Update, Issue #3 [On-line information]. Available online at http://www.annals.org/issues/v135n5/full/200109040-00013.html through http://www.annals.org.

Chapter 132 Thrombotic Disorders, General. The Merck Manual of Diagnosis and Therapy, Section 11. Hematology And Oncology [Online information]. Available online at http://www.merck.com/pubs/mmanual/section11/chapter132/132a.htm through http://www.merck.com.

Protein C Deficiency. University of Illinois - Urbana/Champaign, Carle Cancer Center, Hematology Resource Page, Patient Resources [On-line information]. Available online at http://www-admin.med.uiuc.edu/hematology/PtProtC.htm through http://www-admin.med.uiuc.edu.

Protein S Deficiency. University of Illinois - Urbana/Champaign, Carle Cancer Center, Hematology Resource Page, Patient Resources [On-line information]. Available online at http://www-admin.med.uiuc.edu/hematology/PtProtS.htm through http://www-admin.med.uiuc.edu.

Bardi, J. (2002). Mysteries of a Therapy Unveiled. The Scripps Research Institute, News & Views [On-line Newsletter]. Available online at http://www.scripps.edu/newsandviews/e_20020617/print-ruf.html through http://www.scripps.edu.

Elstrom, R. (2001 October 28, Updated). Protein C. MedlinePlus Health Information, Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003659.htm.

Elstrom, R. (2001 October 28, Updated). Protein S. MedlinePlus Health Information, Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003660.htm.

Coagulation Test Panels. Clinical and Research Laboratories, Florida Hospital Cancer Institute [On-line information]. Available online at http://www.fhci-labs.com/researchlabs/clinicallabs/hemostasisandthrombosis/panels.htm through http://www.fhci-labs.com.

Laposata, M. & Vancott, E. (2000 January). How to work up hypercoagulability. CAP In the News [On-line Coagulation Case Study]. Available online at http://www.cap.org/CAPToday/casestudy/coag5.html through http://www.cap.org.

Venomous Bites and Stings. The Merck Manual of Medical Information-Home Edition, Section 24. Accidents and Injuries, Chapter 287 [On-line information]. Available online at http://www.merck.com/mrkshared/mmanual_home/sec24/287.jsp through http://www.merck.com.

Menta, S. (1999 Spring). The Coagulation Cascade. Physiology Disorders Evaluation, College of Medicine, Univ of Florida [On-line information]. Available online at http://www.medinfo.ufl.edu/year2/coag/title.html through http://www.medinfo.ufl.edu.

Bauer, K. (2001). The Thrombophilias: Well-Defined Risk Factors with Uncertain Therapeutic Implications. Ann Intern Med. 2001;135:367-373 [Journal]. Available online through http://www.annals.org.

DeLoughery, T. (1999 March 15). Tests of Hemostasis and Thrombosis. OHSU [Online student handout]. Available online at http://www.ohsu.edu/som-hemonc/handouts/deloughery/printtest.html through http://www.ohsu.edu.

(2001 January 10, Modified). Coagulation Test Descriptions. Clinical Coagulation Laboratory, A division of Duke University Regional Referral Laboratory Services [Online information]. Available online at http://pathology.mc.duke.edu/coag/TestDes.htm through http://pathology.mc.duke.edu.

Pagana, Kathleen D. & Pagana, Timothy J. (© 2007). Mosby's Diagnostic and Laboratory Test Reference 8th Edition: Mosby, Inc., Saint Louis, MO. P 781-782.

Nanda, R. (2005 April 15). Congenital protein C or S deficiency. MedlinePlus [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/000559.htm. Accessed on 3/25/07.

Nanda, R. (2005 April 15). Protein C. MedlinePlus [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003659.htm. Accessed on 3/25/07.

Nanda, R. (2005 April 15). Protein S. MedlinePlus [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003660.htm. Accessed on 3/25/07.

(© 2007). Laboratory Issues in Diagnosing Abnormalities of Protein C, Thrombomodulin, and Endothelial Cell Protein C Receptor. CAP [On-line information]. Available online through http://www.cap.org. Accessed on 3/25/07.

(© 2007). A Review of the Technical, Diagnostic, and Epidemiological Considerations for Protein S Assays. CAP [On-line information]. Available online through http://www.cap.org. Accessed on 3/25/07.

Dugdale, D. et. al. (Updated 2009 March 2). Protein C. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003659.htm. Accessed September 2010.

Dugdale, D. et. al. (Updated 2010 March 28). Congenital protein C or S deficiency. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/000559.htm. Accessed September 2010.

Cuker, A. and Pollak, E. (Updated 2009 June 11). Protein C Deficiency. eMedicine [On-line information]. Available online at http://emedicine.medscape.com/article/205470-overview through http://emedicine.medscape.com. Accessed September 2010.

(Reviewed 2009 October). Protein C deficiency. Genetics Home Reference [On-line information]. Available online at http://ghr.nlm.nih.gov/condition/protein-c-deficiency through http://ghr.nlm.nih.gov. Accessed September 2010.

(Reviewed 2009 October). Protein S deficiency. Genetics Home Reference [On-line information]. Available online at http://ghr.nlm.nih.gov/condition/protein-s-deficiency through http://ghr.nlm.nih.gov. Accessed September 2010.

Spence, R. et. al. (Updated 2010 January 12). Hemostatic Disorders, Nonplatelet eMedicine. [On-line information]. Available online at http://emedicine.medscape.com/article/210467-overview through http://www.nlm.nih.gov. Accessed September 2010.

Godwin, J. (Updated 2009 August 27). Protein S Deficiency. eMedicine [On-line information]. Available online at http://emedicine.medscape.com/article/205582-overview through http://emedicine.medscape.com. Accessed September 2010.

Pagana, K. D. & Pagana, T. J. (© 2007). Mosby's Diagnostic and Laboratory Test Reference 8th Edition: Mosby, Inc., Saint Louis, MO. Pp 781-782.

Wu, A. (© 2006). Tietz Clinical Guide to Laboratory Tests, 4th Edition: Saunders Elsevier, St. Louis, MO. Pp 922-923, 926-927.

National Blood Clot Alliance. Protein C deficiency. Available online at http://www.stoptheclot.org/News/article136.htm through http://www.stoptheclot.org. Accessed September 2010.

National Blood Clot Alliance. Protein S deficiency: a clinical perspective. Available online at http://www.stoptheclot.org/News/article137.htm through http://www.stoptheclot.org. Accessed September 2010.