[A rare cause of hypoglycaemia in a patient with type 2 diabetes].
BACKGROUND
Insulinomas are rare neuroendocrine tumours with an incidence of four cases per million a year. Only few cases of insulinoma in patients with preexisting diabetes mellitus have been reported.


METHODS
We present a 50-year-old male with type 2 diabetes mellitus who suffered from recurring hypoglycemia. He had gained 20 kilograms of weight in five years. 72-hour fast revealed hypoglycaemia in the presence of inadequately high C-peptide and insulin levels. Magnetic resonance imaging and selective arterial calcium stimulation test confirmed a mass in the body of the pancreas. The tumor was removed surgically. Pathological examination demonstrated a benign insulinoma. Postoperatively, blood glucose levels were within the therapeutic range. The HbA (1c) value was 6.8 % three months after the intervention.


CONCLUSIONS
Clinicians should be alert to insulinoma as a, though rare, differential diagnosis of hypoglycaemia in diabetes, in particular in patients with recurrent, otherwise unexplained hypoglycaemia.
Heni
M
M
Medizinische Universitätsklinik Tübingen, Abteilung für Endokrinologie, Diabetologie, Nephrologie, Angiologie und Klinische Chemie.
Schott
S
S
Horger
M
M
Dudziak
K
K
Thamer
C
C
Häring
H-U
HU
Fritsche
A
A
Müssig
K
K
D001786:Blood Glucose / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications*; D003937:Diagnosis, Differential; D006801:Humans; D006946:Hyperinsulinism / Q000209:etiology; D007003:Hypoglycemia / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007340:Insulinoma / Q000097:blood / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000097:blood / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D016896:Treatment Outcome
D001786:Blood Glucose; D007328:Insulin