Insulinoma in chronic renal failure: a case report

Area of Science:

• Endocrinology
• Nephrology
• Gastroenterology

Background:

• Insulinoma diagnosis typically relies on a 72-hour fast, but renal function can complicate interpretation.
• Renal failure can cause spontaneous hypoglycemia unrelated to insulinoma.
• This case highlights diagnostic challenges in patients with impaired renal function.

Observation:

• A patient with a history of renal impairment and transplant experienced hypoglycemic symptoms for 20 years.
• Standard 72-hour fasting tests suggested endogenous hyperinsulinemia but were complicated by renal impairment.
• Endoscopic ultrasonography was crucial for locating the insulinoma.

Findings:

• Successful surgical resection of the insulinoma was performed.
• This case represents one of the few documented instances of insulinoma in a patient with concurrent renal failure.
• Endoscopic ultrasonography proved effective for tumor localization when fasting tests were equivocal.

Implications:

• The diagnostic criteria for insulinoma may need adjustment in patients with renal impairment.
• Endoscopic ultrasonography is a valuable tool for diagnosing insulinoma in complex renal cases.
• Further research is needed to understand hypoglycemia in renal failure and its distinction from insulinoma.