発症前の膵組織を観察し，発症の臨床経過を観察し得た劇症1型糖尿病の1例

Abstract

症例は66歳男性. 62歳時に膵体尾部腫瘤に対し膵体尾部切除術を施行された. 腫瘍の病理組織は非機能性内分泌腫瘍で, 正常膵組織の膵島構造は保たれ, 炎症細胞浸潤は認めなかった. 術前検査で, 空腹時血糖値97mg/dL, HbA1c 5.8%であった. 63歳時に空腹時血糖122mg/dL, HbA1c 6.3%を認め当科に紹介受診. 抗GAD抗体陰性で, 空腹時CPR 1.39ng/mL, HbA1cは6.5%未満で経過した. A病院に療養入院中に心窩部痛の出現から7日目に意識障害と著明な高血糖(825mg/dL), HbA1c 6.9%を認め, インスリン投与が開始された. その後B病院への転院を経て精査加療目的に当院当科に転院となった. 内因性インスリン分泌の枯渇と発症経過から劇症1型糖尿病と診断した. 劇症1型糖尿病の臨床経過と発症前の膵標本を観察し得た貴重な症例であり, 文献的考察を加えて報告する.

A 66-year-old man was admitted to our hospital for glycemic control of fulminant type 1 diabetes (T1DM). At 62 years old, a pancreatic tail mass lesion had been noted, and the patient underwent partial pancreatectomy. Hormonal and pathological examinations revealed a non-functioning endocrine tumor. Although his pancreatic volume was reduced, glycemic control was maintained (HbA1c value <6.5 %) without medication for 4 years. At 65 years old, during hospitalization for rehabilitation for orthopedic disease, epigastric pain occurred, and 1 week later, his consciousness deteriorated rapidly. A laboratory examination showed an extremely high blood glucose level (827 mg/dL) accompanied by an increased serum amylase level, while elevation of HbA1c was relatively mild (6.9 %). Insulin therapy was initiated, and the patient was then transferred to our hospital. Serum C-peptide was undetectable, and he was diagnosed with fulminant T1DM. We then re-evaluated the pancreas specimen obtained four years earlier. Pancreatic islets outside the endocrine tumor showed no abnormal findings and no invasion of inflammatory cells, which indicated morphologically normal pancreatic islets four years before the onset of fulminant T1DM. We also document the detailed clinical course of fulminant T1DM in the hospital.