How about colon bleeding or inflammation? What other biomarkers could be evaluated?
Low fibrinogen can be linked with recurrent miscarriages, which may have a genetic factor. Low fibrinogen can also contribute to a disruption in hemostasis and an increased risk of bleeding. Additional markers should be evaluated with GI bleeding.
Fibrinogen, the primary precursor to the blood clotting protein fibrin, is vital to hemostasis. It also affects immunity, wound healing, atherosclerosis, and pregnancy maintenance—lack of fibrinogen results in miscarriage despite initial fertilization and ovum implantation (Iwaki 2005).
Genetically determined hypofibrinogenemia has been directly associated with miscarriage, fetal growth restriction, placental abruption, and premature delivery (Sucker 2022). Specific hereditary fibrinogen-related disorders associated with miscarriage include afibrinogenaemia, hypofibrinogenaemia, dysfibrinogenaemia, and hypodysfibrinogenaemia (Valiton 2019).
In one case-control study of 100 women, 50 with recurrent miscarriages, mean fibrinogen levels were significantly lower in cases than in controls, i.e., 149.9 mg/dL (4.4 umol/L) versus 284.3 mg/dL (8.36 umol/L), respectively, Approximately 32% of those with a history of miscarriage experienced three miscarriages, while 68% experienced more than three miscarriages (Mohamed 2021).
Low fibrinogen is associated with bleeding and could be a factor in GI bleeding.
However, fibrinogen increases with the severity of inflammation and disease in inflammatory bowel disease. A fibrinogen level above 3.22 mg/dL (9.47 mol/L) in ulcerative colitis or above 3.87 mg/dL (11.38 mol/L) in Crohn’s may indicate active disease (Chen 2021).
Although we are unable to provide diagnostic or clinical guidance, other markers that may be useful to asses with GI bleeding include iron, RBC biomarkers, lactate dehydrogenase, total protein, and BUN. Variations between these biomarker levels may also help differentiate between upper and lower GI bleeding. An upper GI bleed is associated with significantly higher BUN, especially above 21 mg/dL (7.5 mmol/L), and significantly decreased hemoglobin, total protein, LDH, and HbA1C compared to a lower GI bleed (Tomizawa 2015).
Learn more about Fibrinogen here: ODX Fibrinogen
Reference
Chen, Xiao-Fu et al. “Predictive value of fibrinogen in identifying inflammatory bowel disease in active stage.” BMC gastroenterology vol. 21,1 472. 15 Dec. 2021, doi:10.1186/s12876-021-02040-9
Iwaki, Takayuki, and Francis J Castellino. “Maternal fibrinogen is necessary for embryonic development.” Current drug targets vol. 6,5 (2005): 535-9. doi:10.2174/1389450054546006
Mohamed, Eman Ibrahim, Maye M. Merghani, and Nihad Elsadig Babiker. "Estimation of Fibrinogen level among Sudanese women with recurrent miscarriage." Journal of Drug Delivery and Therapeutics 11.6-S (2021): 140-144
Sucker, Christoph et al. “Hypofibrinogenemia and miscarriage: report of a first successful pregnancy under fibrinogen substitution and short review of the literature.” Archive of clinical cases vol. 9,3 100-103. 26 Sep. 2022, doi:10.22551/2022.36.0903.10211
Tomizawa, Minoru et al. “Laboratory test variables useful for distinguishing upper from lower gastrointestinal bleeding.” World journal of gastroenterology vol. 21,20 (2015): 6246-51. doi:10.3748/wjg.v21.i20.6246
Valiton, Vivian et al. “Obstetrical and postpartum complications in women with hereditary fibrinogen disorders: A systematic literature review.” Haemophilia : the official journal of the World Federation of Hemophilia vol. 25,5 (2019): 747-754. doi:10.1111/hae.13825