Whole blood clotting test

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Whole blood clotting test
Purposeto check coagulation mechanism in the blood following a snake bite

The whole blood clotting test is a blood test used to check the coagulation mechanism in the blood following a snake bite. [1] If the test is positive after a bite in South East Asia it indicates the snake was a viper rather than an elapid. [1] It can also be used to assess the effectiveness of antivenin therapy. [2]

Method

This test indirectly measures the severity of defibrinogenation in envenomed samples. [3] The test is done by collecting 2 ml of venous blood in a dry and clean glass tube. The clot and stability of the formed clot is checked after 20 minutes. [4]

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References

  1. 1 2 Guidelines for the management of snake-bites (PDF). WHO. 2010. p. 73. ISBN   978-92-9022-377-4. Archived from the original (PDF) on February 9, 2014.{{cite book}}: CS1 maint: ignored ISBN errors (link)
  2. Chippaux, J. P.; Williams, V.; White, J. (1991). "Snake venom variability: methods of study, results and interpretation". Toxicon. 29 (11): 1279–1303. doi:10.1016/0041-0101(91)90116-9. ISSN   0041-0101. PMID   1814005.
  3. Sano-Martins, I. S.; Fan, H. W.; Castro, S. C.; Tomy, S. C.; Franca, F. O.; Jorge, M. T.; Kamiguti, A. S.; Warrell, D. A.; Theakston, R. D. (September 1994). "Reliability of the simple 20 minute whole blood clotting test (WBCT20) as an indicator of low plasma fibrinogen concentration in patients envenomed by Bothrops snakes. Butantan Institute Antivenom Study Group". Toxicon. 32 (9): 1045–1050. doi:10.1016/0041-0101(94)90388-3. ISSN   0041-0101. PMID   7801340.
  4. Benjamin, Jordan Max; Chippaux, Jean-Philippe; Sambo, Bio Tamou; Massougbodji, Achille (2018-05-16). "Delayed double reading of whole blood clotting test (WBCT) results at 20 and 30 minutes enhances diagnosis and treatment of viper envenomation". The Journal of Venomous Animals and Toxins Including Tropical Diseases. 24: 14. doi: 10.1186/s40409-018-0151-1 . ISSN   1678-9199. PMC   5956810 . PMID   29796013.