Point-of-care ultrasound for the early diagnosis of emphysematous pyelonephritis: A case report and literature review

Abstract

BACKGROUND Emphysematous pyelonephritis (EPN) is a rare but fatal necrotic infection of the kidney, which usually leads to septic shock. Therefore, early diagnosis and optimized therapy are of paramount importance. In the past two decades, point-of-care ultrasound (POCUS) has been widely used in clinical practice, especially in emergency and critical care settings, and helps to rapidly identify the source of infection in sepsis. We report a rare case in which a “falls” sign on POCUS played a pivotal role in the early diagnosis of EPN. CASE SUMMARY A 57-year-old man presented with fever and lumbago for 3 d prior to admission. He went to the emergency room, and the initial POCUS detected gas bubbles in the hepatorenal space showing a hyperechoic focus with dirty shadowing and comet-tail artifacts. This imaging feature was like a mini waterfall. His blood and urine culture demonstrated Escherichia coli bacteremia, and EPN associated with septic shock was diagnosed. The patient did not respond to broad-spectrum antibiotic treatment and a perirenal abscess developed. He subsequently underwent computed tomography-guided percutaneous catheter drainage, and fully recovered. We also review the literature on the sonographic features of POCUS in EPN. CONCLUSION This case indicates that a “falls” sign on POCUS facilitates the rapid diagnosis of severe EPN at the bedside.

Cavernous Sinus Involvement and Near Miss Mediastinitis following Mandibular Tooth Infection Treated during the COVID-19 Pandemic: Clinical Diagnosis and Treatment

“…After proliferation in necrotic or anoxic areas, Clostridia can release toxins and enzymes (hyaluronidase and hemolysin), producing gas gangrene infection. In another article, Xing et al [ 61 ] described a case of emphysematous pyelonephritis (EPN), a lethal necrotic infection of the kidney with collection of gas in the renal parenchyma, and/or perinephric tissues [ 62 ]. Point-of-care ultrasound (POCUS) detected gas bubbles in the hepatorenal space.…”

Indications for Percutaneous Drainage in Patients with Huang Class 3B Emphysematous Pyelonephritis: A Case Report and Literature Review

“…In classes 3A and 3B, nephrectomy is recommended if two or more risk factors (thrombocytopenia, acute renal failure, disturbance of consciousness, and shock) are present. However, there have been reports of PCD in 3B patients with high-risk factors (3)(4)(5)(6)(7)(8). In addition, the kidney function is decreased by nephrectomy in renal transplant donors, and it is preferable to preserve the kidney if possible (11).…”

“…PCD was performed in 19.4% of the patients. Twelve Class 3B patients underwent PCD (Table 4) (3)(4)(5)(6)(7)(8)(12)(13)(14)(15)(16)(17). Extensive renal parenchymal destruction was defined as the destruction of the renal parenchyma from the upper pole to the lower pole.…”

“…Percutaneous drainage (PCD) is recommended for patients with fewer than two risk factors (thrombocytopenia, acute renal failure, disturbance of consciousness, and shock) in Class 3B, and nephrectomy is recommended for such patients with two or more risk factors (2). In recent years, patients with two or more risk factors have undergone PCD and been cured (3)(4)(5). However, other patients did not improve after PCD and required nephrectomy or even died (6)(7)(8).…”

Successful nephrectomy after a failure of non-surgical treatment in emphysematous pyelonephritis: A case report

“…Imaging modality plays a major role in diagnosing and managing genitourinary conditions, including EP [ 4 , 5 ]. Ultrasonography is helpful in showing gas bubbles in the hepatorenal space, as evidenced by a hyperechoic focus of dirty shadowing and comet-tail artefacts, mimicking a “mini-waterfall” [ 6 ]. Abdominal CT is necessary for early diagnosis and further management [ 1 ].…”