Clinical Manifestation of 16 cases with Insulinoma or Nesidioblastosis / 대한내과학회지

ABSTRACT

Insulinoma is the most important cause of hyperinsulinemic hypoglycemia. Insulinoma can be cured by surgical management but diagnosis and localization are difficult due to their small size and variable clinical manifestation. We studied clinical manifestation of the patients who were diagnosed as insulinoma or nesidioblastosis. METHODS: We studied clinical charts of 16 patients who underwent operation under the impression of insulinoma from 1990 to 1997. RESULTS: 1) Of the 16 patients, 13 had insulinoma and 3 had nesidioblastosis. 2) Neuroglycopenic symptoms were present in all cases. Among them, loss of consciousness or confusion were present in 12 cases (75%). Adrenergic symptoms were present in 9 cases (56%). Mean symptom duration until diagnosis was 39 months(range; 15days~10years). 3) 72 hr fasting test showed hypoglycemia in all cases. 4) Insulin/glucose ratio was above 0.3 except for two cases. 5) CT and MRI had low sensitivity (38%) and specificity (33%) as a preoperative tumor localization tool, and more invasive technique, i.e., selective angiography and transhepatic portal vein sampling, were necessary in most cases. CONCLUSION: Nsidioblastosis may be more prevalent than previously suspected. Diagnosis of insulinoma is not always easy and invasive diagnostic methods should be considered when the clinical suspicion is high, even if biochemical and noninvasive localization tools give negative results.