Emphysematous pyelonephritis

Abstract

Study Type – Therapy (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? Emphysematous pyelonephritis (EPN) is a severe necrotizing infection of the renal parenchyma. The clinical course of EPN can be severe and life‐threatening if not recognized and treated promptly. Most of the information has been from case reports, a few large series have also been reported. Using an evidence‐based approach, this review describes the pathogenesis, classification, complications, and management of EPN. Emphysematous pyelonephritis (EPN) is an acute severe necrotizing infection of the renal parenchyma and its surrounding tissues that results in the presence of gas in the renal parenchyma, collecting system, or perinephric tissue. The cause for mortality in EPN is primarily due to septic complications. Up to 95% of the cases with EPN have underlying uncontrolled diabetes mellitus. The risk of developing EPN secondary to a urinary tract obstruction is about 25–40%. There are three classifications of EPN based on radiological findings. Acute renal failure, microscopic or macroscopic haematuria, severe proteinuria are other positive findings in EPN. Escherichia coli is the most common causative pathogen with the organism isolated on urine or pus cultures in nearly 70% of the reported cases. A plain radiograph shows an abnormal gas shadow in the renal bed raising the suspicion whereas an ultrasound scan or computed tomography (CT) will confirm the presence of intra‐renal gas thus supporting the diagnosis of EPN. Gas may extend beyond the site of inflammation to the sub capsular, perinephric and pararenal spaces. In some cases, gas was found to be extending into the scrotal sac and spermatic cord. Subsequent case studies have shown patients being successfully treated with PCD when used in addition to medical management, with significant reduction in the morality rates. PCD should be performed on patients who have localized areas of gas and functioning renal tissue is present. The treatment strategies include MM alone, PCD plus MM, MM plus emergency nephrectomy, and PCD plus MM plus emergency nephrectomy. In small proportion of patients managed with MM and PCD, subsequent nephrectomy will be required and in these patients the reported mortality is 6.6% Nephrectomy in patients with EPN can be simple, radical or laparoscopic.

Successful management of bilateral emphysematous pyelonephritis with abscess formation in a chronic hemodialysis patient: a case report

“…Bacteremia is present in more than 50 % of the patients, and the organisms are the same as those in urine or pus culture [14]. Based on the blood and urine cultures, the causative pathogens of EPN in the present case were assumed to be Escherichia coli alone or both Enterococcus faecalis and Escherichia coli.…”

“…Escherichia coli is the most common causative pathogen of EPN, with the organism isolated from urine or pus cultures in nearly 70 % of the reported cases [14]. Bacteremia is present in more than 50 % of the patients, and the organisms are the same as those in urine or pus culture [14].…”

Emphysematous pyelonephritis

“…1 Once high levels of tissue glucose, presence of glucose-fermenting organisms (gas-forming coliform bacteria such as E. coli or Klebsiella pneumoniae), and ureteral obstruction coexist, a urinary tract infection may progress to EPN. [1][2][3] Plain abdominal radiography may show abnormal gas in the renal bed or collecting system. 1 CT is the preferred diagnostic modality because of its high sensitivity and ability to assess the extent of gas patterns.…”

“…[1][2][3] Plain abdominal radiography may show abnormal gas in the renal bed or collecting system. 1 CT is the preferred diagnostic modality because of its high sensitivity and ability to assess the extent of gas patterns. 1,3 Treatment of EPN comprises fluid resuscitation, correction of electrolytes and glucose abnormalities, and aggressive antibiotics with Gram-negative bacteria coverage.…”

“…1 CT is the preferred diagnostic modality because of its high sensitivity and ability to assess the extent of gas patterns. 1,3 Treatment of EPN comprises fluid resuscitation, correction of electrolytes and glucose abnormalities, and aggressive antibiotics with Gram-negative bacteria coverage. Definitive surgical management includes percutaneous drainage or nephrectomy for overwhelming sepsis with extensive gas and renal destruction.…”