Zusammenfassung
History and admission findings: A seventy-seven year-old woman with an unclear tumor of the liver suffered from recurrent hypoglycemia and was therefore admitted to our hospital. As diabetes mellitus, hyperinsulinism and reactive forms of hypoglycemia could be excluded, the presumptive diagnosis was non-islet-cell tumor hypoglycemia (NICTH). Investigations: Postprandial glucose levels were ...
Zusammenfassung
History and admission findings: A seventy-seven year-old woman with an unclear tumor of the liver suffered from recurrent hypoglycemia and was therefore admitted to our hospital. As diabetes mellitus, hyperinsulinism and reactive forms of hypoglycemia could be excluded, the presumptive diagnosis was non-islet-cell tumor hypoglycemia (NICTH). Investigations: Postprandial glucose levels were normal. Fasting glucose levels were 30-50mg/dl. Plasma insulin-like growth factor (IGF)-I was below the normal range, IGF-II was not elevated, although 34% of plasma IGF-II was present as "big"-IGF-II. IGF-binding protein (IGFBP)-2 was extremely elevated, whereas IGFBP-3 was within the normal range. Histological examinations of the tumor revealed a hemangiopericytoma of the liver. Treatment and course: After a 2-month treatment with Steroids and an experimental antiangiogenetic therapy, the glucose metabolism became stable. The tumour did not grow. Simultaneously, plasma IGF-II and "big"-IGF-II remained constant and plasma IGF-I level improved slightly. IGFBP-2, which is presumable produced by the tumor, increased, IGFBP-3 fell below the normal range. Conclusion: NICTH is a rare but important differential diagnosis of recurrent hypoglycemia. The tumor derived IGF-II has a higher than normal molecular weight ("big"-IGF-II) and shows different interactions with binding proteins, thus resulting in an increased bioavailability. An increased glucose uptake in different tissues as well as inhibition of hepatic gluconeogenesis and lipolysis lead to severe hypoglycemia. If surgical therapy of the tumor is not possible, symptomatic treatment with steroids may represent an effective alternative to control severe hypoglycemia.