Pneumomediastinum, pneumoperitoneum, and pneumoretroperitoneum caused by Escherichia coli retroperitoneal abscess in a diabetic patient

Abstract

Dear Editor Gas-containing retroperitoneal abscess, usually caused by retroperitoneal organs infection or perforation, is a rare, complicated and serious infection. There are no specific symptoms or signs leading to this diagnosis. We report a case of gas-forming retroperitoneal abscess that caused concurrent pneumomediastinum, pneumoperitoneum, and pneumoretroperitoneum in a patient with poorly controlled diabetes. A 59-year-old woman with diabetes mellitus visited our emergency department complaining of malaise and poor appetite for 1 week, vague epigastric pain, abdominal fullness and dyspnea on exertion recently. Her abdomen was soft, distended, hypoactive and displayed tenderness over the epigastric region. Laboratory survey showed bandemia (48%), hyperglycemia (935 mg/dL), elevated C-reactive protein level (475 mg/L), and renal function impairment (blood urine nitrogen: 63.5 mg/dL, creatinine: 2.69 mg/dL). High osmolality (346 milliosmoles/kg), metabolic acidosis (pH: 7.22, PCO2: 28.9 mmHg, HCO3 : 11.7 mmol/L) with ketonemia (>6 mmol/L) were also revealed. Her urinalysis revealed glysuria (3+) and mild pyuria (sediment WBC of 3-5/HPF). Her chest X-ray showed pneumomediastinum (Figure 1A) and her abdominal radiography demonstrated extra-intestinal free air that led us to suspect pneumoperitoneum and pneumoretroperitoneum (Figure 1B). Computed tomography (CT) of the abdomen (Figure 1C-E) was arranged and it revealed abscess formation with emphysematous change in the left retroperitoneal space and bilateral pneumoretroperitoneum as well as pneumoperitoneum where hollow organ perforation could not be totally excluded. Therefore, exploratory laparotomy was performed and no perforated lesions of hollow organs were found. Drainage of retroperitoneal abscess was also done and she was admitted to the intensive care unit. An elevated serum level of HbA1c (17.4%) was disclosed. Microbial cultures of blood, urine, and abscess all demonstrated Escherichia coli infection. With ertapenem 1 g/day treatment and management, she recovered and was discharged after 18 days of hospitalization. 1 | DISCUSSION