Background: In the evaluation of gastrointestinal (GI) bleeding, accurately identifying whether the source is upper or lower GI is critical for timely and appropriate management. However, determining the bleeding origin can be particularly challenging in cases of isolated melena without hematemesis. Non-invasive, cost-effective diagnostic tools that can aid in early localization are therefore of significant clinical value. Objective: This study aimed to assess the diagnostic performance of the blood urea nitrogen (BUN) to creatinine ratio as a predictor of the bleeding source—upper vs. lower GI—in patients presenting with isolated melena. Methods: We conducted a prospective study involving patients who presented with melena in the absence of hematemesis. Laboratory values including BUN and creatinine levels were collected, and the BUN/creatinine ratio was calculated. Endoscopic evaluations were subsequently performed to determine the actual source of bleeding. Results: Our findings showed that a BUN/creatinine ratio below 50 was highly predictive of upper GI bleeding. In contrast, patients with lower GI bleeding demonstrated significantly higher BUN/creatinine ratios. The ratio proved to be a reliable, non-invasive biochemical marker that could assist in predicting the bleeding source prior to endoscopy. Conclusion: The BUN/creatinine ratio offers a simple, accessible, and effective means to guide clinical triage in patients with isolated melena. Its use could enhance early decision-making and improve patient outcomes by facilitating prompt diagnostic and therapeutic interventions.
| Published in | American Journal of Medical Science and Technology (Volume 1, Issue 1) |
| DOI | 10.11648/j.ajmst.20250101.12 |
| Page(s) | 9-13 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2025. Published by Science Publishing Group |
Gastrointestinal Hemorrhage, Melena, Bun/Creatinine Ratio, Diagnostic Marker, Non-Invasive Triage
| [1] | Barkun AN, Bardou M, Kuipers EJ, et al. International consensus recommendations on the management of patients with nonvariceal upper gastrointestinal bleeding. Ann Intern Med. 2010; 152(2): 101-13. |
| [2] | Snook JA, Holdstock GE, Bamfort J. A simple biochemical ratio to distinguish upper from lower GI bleeding sites. Lancet. 1986; ii: 1064–1065. |
| [3] | Pumphrey CW, Beck ER. Elevated blood urea indicates major blood loss in acute upper GI bleeding. BMJ. 1980; i: 527–528. |
| [4] | Stellato T, Rhodes RS, McDougal WS. Azotemia in upper GI bleeding. Am J Gastroenterol. 1980; 73: 486–489. |
| [5] | Kikai Y, Matsuoka K. BUN/creatinine ratio in localizing the bleeding site in pediatric patients with GI bleeding. Nippon Ika Daigaku Zasshi. 1990; 57: 297–307. |
| [6] | Olsen LH, Andreassen KH. Altered BUN/creatinine ratio as a simple test to identify bleeding origin. Br J Surg. 1991; 78: 71–73. |
| [7] | Calim S, Kaya Y, Ozhan A, Dogan S. Diagnosis value of the blood urea nitrogen to creatinine ratio in determining the need for intervention of acute upper gastrointestinal bleeding. North Clin Istanb. 2025; 12(2): 123–130. |
| [8] | Feng Z, Zhang H, Li Y, Wu D. Predictive value of blood urea nitrogen/creatinine ratio in upper GI bleeding. J Surg Res. 2022; 278: 321–327. |
| [9] | Liu H, Zhao Y, Li L, Sun W. Association between BUN/creatinine ratio and poor outcomes in non-variceal upper gastrointestinal bleeding. Front Med. 2024; 11: 38531324. |
| [10] | Martin-Simadibrata M, et al. Prognostic accuracy of BUN/creatinine ratio in acute GI bleeding: A meta-analysis. BMC Gastroenterol. 2025; 25(1): 22–30. |
| [11] | Zhao W, Liu Y, Chen Y. Use of BUN/Cr ratio in predicting endoscopic intervention in GI bleeding. Int J Gen Med. 2023; 16: 443–450. |
| [12] | Yildiz E, Kara I, Gungor T. Relationship between blood urea nitrogen/creatinine ratio and severity of acute gastrointestinal bleeding. Turk J Emerg Med. 2023; 23(1): 10–14. |
| [13] | Wang Y, Zhou M, Zhang X. BUN/Cr ratio and hospital mortality in patients with acute pancreatitis. Eur J Med Res. 2025; 30(1): 24–30. |
| [14] | Almasri M, Safadi A, Farah R. The blood urea nitrogen to creatinine ratio predicts mortality in patients with decompensated heart failure. Cardiorenal Med. 2023; 13(1): 16–21. |
| [15] | Tang J, Li L, Liu D. Dynamic changes in BUN/Cr ratio as a marker of prognosis in GI bleeding. Am J Emerg Med. 2024; 42: 133–139. |
| [16] | Kobayashi S, Ueno T, Katayama Y. Clinical usefulness of BUN/Cr ratio in triaging patients with suspected GI bleeding in the emergency department. BMC Emerg Med. 2023; 23(1): 58. |
| [17] | Zhang X, Wu L, Yu M. Value of BUN/Cr ratio combined with AIMS65 in early risk assessment of upper GI bleeding. J Dig Dis. 2024; 25(4): 206–213. |
APA Style
Gharbi, K., Akka, R. (2025). Blood Urea Nitrogen to Creatinine Ratio as a Predictor of Upper or Lower Source of Melena: A Prospective Study. American Journal of Medical Science and Technology, 1(1), 9-13. https://doi.org/10.11648/j.ajmst.20250101.12
ACS Style
Gharbi, K.; Akka, R. Blood Urea Nitrogen to Creatinine Ratio as a Predictor of Upper or Lower Source of Melena: A Prospective Study. Am. J. Med. Sci. Technol. 2025, 1(1), 9-13. doi: 10.11648/j.ajmst.20250101.12
@article{10.11648/j.ajmst.20250101.12,
author = {Khalid Gharbi and Rachid Akka},
title = {Blood Urea Nitrogen to Creatinine Ratio as a Predictor of Upper or Lower Source of Melena: A Prospective Study},
journal = {American Journal of Medical Science and Technology},
volume = {1},
number = {1},
pages = {9-13},
doi = {10.11648/j.ajmst.20250101.12},
url = {https://doi.org/10.11648/j.ajmst.20250101.12},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajmst.20250101.12},
abstract = {Background: In the evaluation of gastrointestinal (GI) bleeding, accurately identifying whether the source is upper or lower GI is critical for timely and appropriate management. However, determining the bleeding origin can be particularly challenging in cases of isolated melena without hematemesis. Non-invasive, cost-effective diagnostic tools that can aid in early localization are therefore of significant clinical value. Objective: This study aimed to assess the diagnostic performance of the blood urea nitrogen (BUN) to creatinine ratio as a predictor of the bleeding source—upper vs. lower GI—in patients presenting with isolated melena. Methods: We conducted a prospective study involving patients who presented with melena in the absence of hematemesis. Laboratory values including BUN and creatinine levels were collected, and the BUN/creatinine ratio was calculated. Endoscopic evaluations were subsequently performed to determine the actual source of bleeding. Results: Our findings showed that a BUN/creatinine ratio below 50 was highly predictive of upper GI bleeding. In contrast, patients with lower GI bleeding demonstrated significantly higher BUN/creatinine ratios. The ratio proved to be a reliable, non-invasive biochemical marker that could assist in predicting the bleeding source prior to endoscopy. Conclusion: The BUN/creatinine ratio offers a simple, accessible, and effective means to guide clinical triage in patients with isolated melena. Its use could enhance early decision-making and improve patient outcomes by facilitating prompt diagnostic and therapeutic interventions.},
year = {2025}
}
TY - JOUR T1 - Blood Urea Nitrogen to Creatinine Ratio as a Predictor of Upper or Lower Source of Melena: A Prospective Study AU - Khalid Gharbi AU - Rachid Akka Y1 - 2025/12/09 PY - 2025 N1 - https://doi.org/10.11648/j.ajmst.20250101.12 DO - 10.11648/j.ajmst.20250101.12 T2 - American Journal of Medical Science and Technology JF - American Journal of Medical Science and Technology JO - American Journal of Medical Science and Technology SP - 9 EP - 13 PB - Science Publishing Group UR - https://doi.org/10.11648/j.ajmst.20250101.12 AB - Background: In the evaluation of gastrointestinal (GI) bleeding, accurately identifying whether the source is upper or lower GI is critical for timely and appropriate management. However, determining the bleeding origin can be particularly challenging in cases of isolated melena without hematemesis. Non-invasive, cost-effective diagnostic tools that can aid in early localization are therefore of significant clinical value. Objective: This study aimed to assess the diagnostic performance of the blood urea nitrogen (BUN) to creatinine ratio as a predictor of the bleeding source—upper vs. lower GI—in patients presenting with isolated melena. Methods: We conducted a prospective study involving patients who presented with melena in the absence of hematemesis. Laboratory values including BUN and creatinine levels were collected, and the BUN/creatinine ratio was calculated. Endoscopic evaluations were subsequently performed to determine the actual source of bleeding. Results: Our findings showed that a BUN/creatinine ratio below 50 was highly predictive of upper GI bleeding. In contrast, patients with lower GI bleeding demonstrated significantly higher BUN/creatinine ratios. The ratio proved to be a reliable, non-invasive biochemical marker that could assist in predicting the bleeding source prior to endoscopy. Conclusion: The BUN/creatinine ratio offers a simple, accessible, and effective means to guide clinical triage in patients with isolated melena. Its use could enhance early decision-making and improve patient outcomes by facilitating prompt diagnostic and therapeutic interventions. VL - 1 IS - 1 ER -