Insulinoma laboratory tests
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Amandeep Singh M.D.[2]
Overview
Overview
Laboratory findings consistent with the diagnosis of insulinoma include serum glucose < 55 mg/dL, serum Insulin > 5-10 μU/mL, serum C-Peptide > 200 pmol/L, and serum proinsulin ≥ 22 pmol/L. Patients with insulinoma may have elevated insulin to glucose ratio of > 0.4, which is usually suggestive of insulinoma after a 72-hour fast test(gold standard test). 33% patients have clinical symptoms within 12 hours of the fasting, 80% develop within 24 hours, 90% develop within 48 hours, and 100% develop within 72 hours.
Laboratory Findings
Laboratory Findings
- Laboratory findings consistent with the diagnosis of insulinoma include:[1]
- Serum glucose < 55 mg/dL
- Serum Insulin > 5-10 μU/mL
- Serum C-Peptide > 200 pmol/L
- Serum proinsulin ≥ 22 pmol/L
- Patients with insulinoma may have elevated insulin to glucose ratio of > 0.4, which is usually suggestive of insulinoma after a 72-hour fast test. It is a gold standard test. [2]
References
References
- ↑ Cryer PE, Axelrod L, Grossman AB, Heller SR, Montori VM, Seaquist ER; et al. (2009). “Evaluation and management of adult hypoglycemic disorders: an Endocrine Society Clinical Practice Guideline”. J Clin Endocrinol Metab. 94 (3): 709–28. doi:10.1210/jc.2008-1410. PMID 19088155.
- ↑ Callender GG, Rich TA, Perrier ND (2008). “Multiple endocrine neoplasia syndromes”. Surg Clin North Am. 88 (4): 863–95, viii. doi:10.1016/j.suc.2008.05.001. PMID 18672144.
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