Outcome of percutaneous nephrostomy for the management of pyonephrosis

Xanthogranulomatous pyelonephritis infected with the Providencia stuartii: a case report and literature review

BACKGROUND

Xanthogranulomatous pyelonephritis (XGP) is a rare and severe chronic inflammatory disease of the renal parenchyma, which is most commonly associated with super-infections by bacteria such as E. coli, Proteus mirabilis, and occasionally Pseudomonas species.

CASE PRESENTATION

Herein, we present a rare case of a patient with XGP infected with Providencia stuartii. Initially, the patient refused nephrectomy and underwent holmium laser lithotripsy and right ureteral stenting, followed by meropenem treatment of 7 days. Relapse occurred in the third month after discharge from the hospital, due to which she underwent a radical nephrectomy.

DISCUSSION

The diagnosis of XGP is confirmed by histopathology. The standard treatment for XGP is antibiotic therapy and radical nephrectomy, but partial nephrectomy may be appropriate in select cases.

A Rare Case of Pyonephrosis in an Infant Induced by Extended-Spectrum Beta-Lactamase-Producing Klebsiella pneumoniae

Pyonephrosis is a rare condition in both adult and pediatric population. Here, the author presents a rare case of pyonephrosis induced by extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in a 12-month-old girl presenting with a picture of urosepsis. The patient presented with febrile urinary tract infection and was unresponsive to intravenous meropenem. Physical examination revealed huge, firm and irregular right renal swelling. Ultrasound and computed tomography imaging revealed severely hydronephrotic right kidney, and laboratory investigations showed elevated C-reactive protein level (22.9 mg/dl). Emergency percutaneous nephrostomy tube was inserted, pus was drained (20 ml) and intravenous vancomycin and amikacin were started. Her general condition improved, and urine culture was negative. Functional assessment with dimercaptosuccinic acid renal scan revealed that the split renal function was 5% on the right and 95% on the left side, and the bladder outline was smooth with no reflux in voiding cystourethrogram. A right nephrectomy was done a week later using the anterior subcostal approach. The postoperative course was smooth. Histopathological examination was diagnostic for xanthogranulomatous pyelonephritis. No adverse events were reported in the follow-up over 12 months. It can be concluded that a high degree of suspicion, rapid initiation of appropriate antibiotics and drainage of pus are crucial in the management of pyonephrosis.

ACR Appropriateness Criteria® Radiologic Management of Urinary Tract Obstruction

Acute obstructive uropathy is a medical emergency, which often is accompanied by acute renal failure or sepsis. Treatment options to resolve the acute obstructive process include conservative medical management, retrograde ureteral stenting, or placement of percutaneous nephrostomy or nephroureteral catheters. It is important to understand the various treatment options in differing clinical scenarios in order to guide appropriate consultation. Prompt attention to the underlying obstructive process is often imperative to avoid further deterioration of the patient's clinical status. A summary of the data and most up-to-date clinical trials regarding treatment options for urinary tract obstruction is outlined in this publication. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Emergent Percutaneous Nephrostomy for Pyonephrosis: A Primer for the On-Call Interventional Radiologist

Pyonephrosis is gross accumulation of pus within an obstructed renal collecting system that, if left untreated, can lead to potentially fatal septic shock. Treatment requires urgent decompression coupled with systemic antibiotics. Percutaneous nephrostomy (PCN) placement, first described in 1976 for the treatment of pyonephrosis, is now widely utilized for emergent decompression in these patients. When performed by an experienced interventional radiologist, PCN is a safe procedure with technical success rates of over 96 to 99%. This article will address the clinical presentation of pyonephrosis, and will discuss the indications, technique, complications, and outcomes of emergent PCN placement. Additionally, the expanded indications for PCN placement in nonemergent scenarios will also be described.

Minimally invasive management of acute ureteral obstruction and severe infection caused by upper urinary tract calculi

PURPOSETo evaluate therapeutic efficacy of two minimally invasive surgical methods in managing acute ureteral obstruction and severe infection caused by upper urinary tract calculi (UUTC).PATIENTS AND METHODSData of 47 patients diagnosed with acute upper urinary tract obstruction and severe infection caused by ureteral calculus using X-ray CT between September 2014 and January 2019 were retrospectively analyzed. All patients were treated with immediate renal drainage and, after infection and ureteral obstruction were relieved, UUTC removal. Renal drainage was performed by ultrasound-guided percutaneous nephrostomy and retrograde ureteral catheterization was performed using cystoscopy. Kidney and ureteral stones were removed; renal function and the urinary tract were examined by X-ray during follow-up.RESULTSPercutaneous nephrostomy was performed in 29 patients in a critical condition including intolerance to surgery, high-grade hydronephrosis, or failure of retrograde ureteric stent placement. In other 18 patients diagnosed with small stones (≤10 mm) and low-grade hydronephrosis, indwelling double-J ureteral stents were temporally installed by a cystoscope. Acute infection and ureteral obstruction were relieved; white blood cell counts returned to normal values within 3 to 7 days after drainage in all patients. In the second-stage treatment, percutaneous nephrolithotomy (PCNL), ureteroscopic lithotripsy, extracorporeal shock wave lithotripsy and nephrectomy were performed in 24, 10, 8 and 5 patients, respectively. No patients developed severe complication after stone removal surgery. All patients were followed up for 3 months to 4.5 years. Renal function was significantly recovered; 17/29 (59%) patients with elevated serum creatinine returned to normal and serum creatinine in 12/29 (41%) patients improved significantly after drainage, with a pre-operation level of 285±169μM vs 203±91μM post-operation (P = 0.014). Five patients were lost during follow-up.CONCLUSIONThis study demonstrated an optimal approach for relieving upper urinary tract obstruction and acute infection in which percutaneous nephrostomy drainage is preferred for patients with severe pyonephrosis, large stones (>10 mm) with high-grade hydronephrosis, steinstrasse, or failure in retrograde ureteric stent placement, while retrograde ureteral catheterization using cystoscopy is suitable for patients diagnosed with small stones (≤10 mm) and low-grade hydronephrosis.

Management of dysfunctional catheters and tubes inserted by interventional radiology

Minimally invasive percutaneous interventions are often used for enteral nutrition, biliary and urinary diversion, intra-abdominal fluid collection drainage, and central venous access. In most cases, radiologic and endoscopic placement of catheters and tubes has replaced the comparable surgical alternative. As experience with catheters and tubes grows, it becomes increasingly evident that the interventional radiologist needs to be an expert not only on device placement but also on device management. Tube dysfunction represents the most common complication requiring repeat intervention, which can be distressing for patients and other health care professionals. This manuscript addresses the etiologies and solutions to leaking and obstructed feeding tubes, percutaneous biliary drains, percutaneous catheter nephrostomies, and drainage catheters, including abscess drains. In addition, we will address the obstructed central venous catheter.

Long-Term Results after Acute Therapy of Obstructive Pyelonephritis

Introduction: To evaluate therapeutic results till 5 years after therapy of obstructive pyelonephritis (OPN) emphasizing regular follow-up. Material and Methods: During 5 years, 57 patients with OPN were treated. The patients' charts were reviewed retrospectively for clinical data. These were completed by a questionnaire. Results: In the group of 57 patients (average age 56 years), about two third were women. Urolithiasis (65%) and tumors (21%) were the main causes of obstruction; fever (91%) and loin pain (86%) the main symptoms. Three fourth of the patients showed renal insufficiency and nearly 50% anemia. E. coli and Proteus spp. were the dominating organisms. Sonography detected obstruction in 93% cases. In one third of cases, CT scan was added; 81% percutaneous nephrostomy and 19% ureteral stenting were the initial methods of urinary drainage. During therapy, 23% nephrectomies (19% complete, 4% partial) were performed. Long-term follow-up showed 11% recurrent OPN and 33% recurrent UTI. Conclusions: After diagnosis of OPN, primary nephrostomy or ureteral stenting and antibiotic therapy are the first measures. If recurrent urinary tract infections or OPN occur, long-term follow-up and low-dose antibiotic prophylaxis may be discussed.

Primary neonatal MRSA pyonephrosis

Pyonephrosis is uncommon in adult and paediatric population and very rare in neonates. Neonatal candidal and staphylococcal pyonephrosis has been reported earlier, and this is the first reported case of MRSA pyonephrosis. A case of potentially lethal fulminating primary MRSA pyonephrosis with septic shock in a neonate in whom investigations showed refluxing and obstructing left megaureter requiring successful surgical correction has been reported.

Radiation-free percutaneous nephrostomy performed on neonates, infants, and preschool-age children

AIM

The aim of this study was to evaluate the effectiveness and safety of high-frequency linear probe ultrasonographic (US) guidance percutaneous nephrostomy (PN) in terms of diagnostic and therapeutic approach in preschool-age children with urological problems.

MATERIALS AND METHODS

PN was performed on 40 kidneys in 33 patients (13 girls, 20 boys) aged 3 days - 7 years (mean 4.1 years). All procedures were performed with US guidance utilizing a Shimadzu SDU 2200 Xplus 5-10 mHz probe. Complete blood count, urinalysis, bladder urine culture, blood urea, and creatinine values were obtained before PN placement on the same day. Urine cultures were obtained by nephrostomy tube and compared to bladder urine culture.

RESULTS

PN procedures were technically successful in 39 kidney units (97.5%). Two major complications were macroscopic hematuria requiring blood transfusions (1 case) and sepsis (1 case). Minor complications were displacement of the catheter (4), urinary tract infection (4), urine extravasation (1), early dislocation of the catheter (1). In three cases, the catheter was replaced. Analysis of bladder urine showed that 13 patients (39.4%) had positive cultures, but analysis of PN urine showed that 25 patients (78.1%) had positive cultures.

CONCLUSIONS

PN is an easy, safe and efficient diagnostic and therapeutic procedure with few complications even in preschool-age children. The antibiotic regimen should be revised in order to avoid sepsis and urinary tract infection.

Effects of renal pelvic high-pressure perfusion on nephrons in a porcine pyonephrosis model

The aim of this study was to investigate the effects of various renal pelvic pressure gradients on nephrons with purulent infection. Five miniature test pigs were selected. One side of the kidney was used to prepare the pyonephrosis model and the other side was used as the healthy control. A piezometer and a water fill tube were inserted into the renal pelvis through the ureter. Prior to perfusion, punctures were made on the healthy and purulent sides of the kidneys to obtain tissues (as controls). Subsequently, a puncture biopsy was conducted on the kidneys at five pressure levels: 10, 20, 30, 40 and 50 mmHg. Once the renal pelvic pressure had increased, the healthy and injured kidneys presented pathological changes, including dilation of the renal tubule and capsule and compression of the renal glomerulus. When the renal pelvic pressure exceeded 20 mmHg, the injured kidney presented more damage. Electron microscopy revealed that the increase in pressure resulted in the following: the podocyte gap widened, the epithelial cells of the renal capsule separated from the basement membrane, the basement membrane thickness became uneven, the continuity of the basement membrane was interrupted at multiple positions and the renal tubule microvillus arrangement became disorganised. The manifestations in the pyonephrosis model were more distinct compared with those in the healthy kidney. As the renal pelvic pressure exceeds 20 mmHg under a renal purulent infection status, the nephrons become damaged. The extent of the damage is aggravated as the pressure is increased.

One-stage tubeless antegrade ureteric stenting: a safe and cost-effective option?

INTRODUCTION

Antegrade insertion of ureteric stent has become an established mode of management of upper tract obstruction secondary to ureteric pathology. It is conventionally performed as a two-stage procedure for various reasons but, more recently, a one-stage approach has been adopted.

PATIENTS AND METHODS

We discuss our experience of primary one-stage insertion of antegrade ureteric stent as a safe and cost-effective option for the management of these difficult cases in this retrospective observational case cohort study of patients referred to a radiology department for decompression of obstructed upper tracts. Data were retrieved from case notes and a radiology database for patients undergoing one-stage and two-stage antegrade stenting. It was followed by telephone survey of regional centres about the prevalent local practice for antegrade stenting. Outcome measures like hospital stay, procedural costs, requirement of analgesia/antimicrobials and complication rates were compared for the two approaches.

RESULTS

a one-stage approach was found to be suitable in most cases with many advantages over the two-stage approach with comparable or better outcomes at lower costs. Some of the limitations of the study were retrospective data collection, more than one radiologist performing stenting procedures and non-availability of interventional radiologist falsely raising the incidence of two-stage procedures.

CONCLUSIONS

In the absence of any clinical contra-indications and subject to availability of an interventional radiologist's support, one-stage antegrade stenting could easily be adopted as a routine approach for the management of benign or malignant ureteric obstruction.

Limitations of caspofungin in the treatment of obstructive pyonephrosis due to Candida glabrata infection

Background

Caspofungin is a new antifungal agent with high-level activity against a number of Candida species including those that are resistant to azoles. Its good safety profile and low nephrotoxicity makes it an attractive drug to treat fungal infections in patients with compromised renal function. However, little is known about the clinical efficacy in the treatment of complicated urinary tract infections due to Candida species such as pyonephrosis.

Case presentation

We report a case of obstructive pyonephrosis due to an azole (fluconazole and itraconazole) resistant Candida glabrata strain that failed to respond to intravenous treatment with caspofungin. A sustained clinical and microbiological response was only achieved after percutaneous drainage and instillation of amphotericin B deoxycholate into the renal pelvis in combination with intravenous liposomal amphotericin B.

Conclusion

This case demonstrates the limitation of intravenous antifungal agents such as caspofungin as the sole treatment of an obstructive upper urinary tract infection due to Candida species. In order to achieve long term sustained cure from an obstructive pyonephrosis, pus and fungal balls should be drained and an anti-fungal agent such as amphotericin B deoxycholate instilled locally. The pharmacokinetics and role of caspofungin in the treatment of complicated Candida urinary tract infection is reviewed.