Emphysematous cystitis and pyelonephritis leading to a diagnosis of type 2 diabetes in an older patient.

Dear Editor,

Emphysematous urinary tract infection is rare, while the co‐occurrence of emphysematous pyelonephritis is even more exceptional. We report a case of an older patient without regular medical follow‐up presenting with a combination of emphysematous cystitis and pyelonephritis that led to a diagnosis of underlying type 2 diabetes mellitus (DM).

An 88‐year‐old man was admitted to the emergency unit of our hospital with delirium and shivering. His past medical history was unremarkable. On examination, the patient was confused, hemodynamically stable and not febrile. He exhibited bilateral pitting oedema up to the thighs, decreased cardiac sounds and breathing sounds at lung bases. There was also a suprapubic tenderness with dullness on percussion. An enlarged prostate without exacerbated pain on touch was found during the rectal exam. The rest of the examination was unremarkable. Blood analysis at hospital admission showed a non‐fasting blood sugar level of 8.4 mmoL/L, a normochromic, normocytic anaemia (Hb 130 mg/L), no leucocytosis and an elevated C‐reactive protein level of 17.6 mg/L. Levels of creatinine and urea were also elevated up to 411 μmol/L and 33 mmoL/L, respectively. eGFR was 10 mL/min/1.73 m2, and the total amount of carbon dioxide was 17.4 mmoL/L. Urine analysis showed a leucocyturia (7537 leucocyte/mm3) associated with a non‐glomerular haematuria (481 red cells/mm3). An ultrasound scan showed the presence of air in the bladder. Therefore, a non‐contrast computed tomography (CT) scan was performed, which revealed extensive intramural air in the bladder wall progressing up to the left kidney with a dilated left ureter and perinephric infiltration (Fig. 1). The bladder was partially filled up with fluid. This was suggestive of emphysematous cystitis and pyelonephritis. The urologist's opinion was that there was no indication to perform drainage with nephrostomy as diuresis was preserved. In order to monitor the urine output and to treat the urinary retention, a perurethral 16 Fr Folley catheter was inserted. Purulent urine was drained after catheterization. Ciprofloxacin was started immediately and was rapidly switched to imipenem for 10 days following results of the urine culture collected at hospital admission and positive within the first 24 h for growth of an extended‐spectrum beta‐lactamase producing Escherichia coli. The two sets of blood cultures collected were negative. The patient was then moved to the intensive care unit for monitoring. This conservative treatment was successful, with clinical improvement and regression of the radiological diagnoses on follow‐up CT. A trial without catheter was unsuccessful, with recurrence of urine retention, leading to long‐term catheterization. Subsequently, type 2 diabetes mellitus was confirmed with a glycated hemoglobin level of 8.4%, associated with micro‐ and macrovascular complications. The patient was later diagnosed with heart failure with reduced ejection fraction, sensorimotor polyneuropathy and chronic kidney disease with a persistent eGFR between 10 and 13 mL/min/1.73 m2. During the acute and post‐acute phases, we observed hyperglycemia varying from 8.6 to 12.5 mmoL/L for fast blood glucose and from 14.2 to 17.8 mmoL/L for post‐prandial glucose. Optimal glycemic control was achieved with an intermittent short‐acting insulin regimen, which was then transitioned to longer‐acting insulin. Moreover, blood markers of inflammation continued to rise within the first 48 h of imipenem and then finally began to decrease after 96 h of treatment, followed by clinical improvement.

Figure 1

Coronal oblique (a) and axial oblique (b) reconstructions of non‐contrast‐enhanced abdominal computed tomography (CT) show intramural air in the bladder wall (a, arrows), an air‐filled dilated left ureter (a, arrowheads), air in the left pelvicalyceal system (b, arrow), and small air bubbles within the left renal parenchyma (b, arrowheads). (c) An axial image of non‐contrast‐enhanced abdominal CT shows intraluminal air (c, asterisk) in the more anterior portion of the bladder, with associated air‐fluid level (c, arrowhead). Note the extensive intramural air (c, arrows).

Emphysematous urinary tract infection (EUTI) is a rare and potentially life‐threatening condition. EUTI is typically observed in older women (60–70 years old), with DM being the most notable risk factor for this condition,1, 2 while acute renal function impairment, proteinuria, changes in mental status and shock are related to poor prognosis.3, 4, 5, 6, 7 The infection is caused by various bacteria, with Escherichia coli being the most prevalent (more than half of the described cases) in urine cultures. The presence of gas‐forming bacteria with high glucose levels in the urinary tract and impaired host response are believed to prompt the development of EUTI.

Clinical presentations are variable (from asymptomatic to severe sepsis) and usually non‐specific (abdominal pain, gross hematuria, dysuria, fever). Diagnosis of EUTI is made in patients with complicated urinary tract infections who underwent imaging assessment by abdominal ultrasound or CT. The use of imaging techniques is probably associated with the increasing reports of this disease. As the gold standard technique, CT assesses the extent of the infection from gas confined in the collecting system only to extensive bilateral emphysematous pyelonephritis. Early treatment with antibiotics, bladder drainage and management of comorbidities are required to avoid complications such as bladder rupture or septic shock, with only a minority of cases requiring surgery.

Patients with diabetes have increased susceptibility to pathogens and subsequent infections. Underlying mechanisms include impairment of cytokine production, defects in phagocytosis and dysfunction of immune cells. Therefore, infections in this population are associated with increased incidence of complications, length of treatment and cost of care.

This case highlights that DM should be screened for in patients presenting with EUTI, as well as the importance of appropriate imaging, an early diagnosis and fast introduction of antibiotic treatment.

Disclosure statement

The authors have no conflicts of interest to declare.