Gourt Home::Gourt :: BUN-to-creatinine ratio
In medicine, the BUN-to-creatinine ratio, also BUN-creatinine ratio and BUN/creatinine ratio, is a ratio of two laboratory test values, the blood urea nitrogen (BUN) and serum creatinine. It is used in the United States; elsewhere (Canada, Europe) urea is used instead of BUN, so it is the urea-to-creatinine ratio, also urea-creatinine ratio and urea/creatinine ratio.
Acute renal failure
It has been found to predictive of pre-renal renal failure, if the BUN-to-creatinine ratio is greater than 20Morgan DB, Carver ME, Payne RB. Plasma creatinine and urea: creatinine ratio in patients with raised plasma urea. Br Med J. 1977 Oct 8;2(6092):929-32. PMID 912370. or the urea-to-creatinine ratio>0.10 and urea>10.Acute renal failure: urea:creatinine ratio was not very helpful in diagnosing prerenal failure. Evidence-Based On-Call database. URL: http://www.eboncall.org/CATs/1844.htm. Accessed on: June 25, 2006.
Gastrointestinal bleeds
It is useful for the diagnosis of upper gastrointestinal bleeding in patients who do not present with overt vomiting of blood.Witting MD, Magder L, Heins AE, Mattu A, Granja CA, Baumgarten M. ED predictors of upper gastrointestinal tract bleeding in patients without hematemesis. Am J Emerg Med. 2006 May;24(3):280-5. PMID 16635697.
In children, a BUN/creatinine ratio of 30 or above has a sensitivity of 68.8% for upper GI bleeding and a specificity of 98%.Urashima M, Toyoda S, Nakano T, Matsuda S, Kobayashi N, Kitajima H, Tokushige A, Horita H, Akatsuka J, Maekawa K. BUN/Cr ratio as an index of gastrointestinal bleeding mass in children. J Pediatr Gastroenterol Nutr. 1992 Jul;15(1):89-92. PMID 1403455.
Elderly patients
Because of decreased muscle mass, elderly patients may have an elevated BUN-to-creatinine ratio at baseline.Feinfeld DA, Bargouthi H, Niaz Q, Carvounis CP. Massive and disproportionate elevation of blood urea nitrogen in acute azotemia. Int Urol Nephrol. 2002;34(1):143-5. PMID 12549657
References
External
"BUN-to-creatinine ratio"