Formation of large abscess tumor including gallstone in ileum during therapy for hyperosmolar hyperglycemic syndrome: a case report.

Hyperosmolar hyperglycemic status (HHS) is one of the most serious acute metabolic complications of diabetes mellitus (DM) and the patients with type 2 DM are immunocompromised host, especially when glycemic control is poor. Under hyperglycemic conditions, we have to pay much attention even for rare infection. Bouveret's syndrome is a rare type of gallstone ileus together with duodenal obstruction secondary to the passage of a stone through a cholecystoduodenal fistula. Herein, we reported a rare case with formation of large abscess tumor, including necrotic ileum and gallstone after taking therapy for HHS. She was under more rare conditions rather than Bouveret's syndrome, because large abscess tumor was formed not in the duodenal bulb but in the ileum together with necrotic ileitis and abdominal abscess with impacted gallstone. We should bear in mind that T2DM patients are immunocompromised host in particular under untreated or poorly controlled conditions and thereby they could have rare inflammatory diseases such as a large abscess tumor. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13340-021-00540-3. © The Japan Diabetes Society 2021.