Early diagnostic model of pyonephrosis with calculi based on radiomic features combined with clinical variables.

OBJECTIVE: This retrospective aims to develop a comprehensive predictive model based on CT radiomic features and clinical parameters, facilitating early preoperative diagnosis of pyonephrosis. METHODS: Clinical and radiological data from 311 patients treated for upper urinary tract stones with obstructive pyelohydronephrosis, between January 2018 and May 2023, were retrospectively collected. Univariate and multivariate logistic regression analyses were conducted on clinical data to identify independent risk factors for pyonephrosis. A clinical model was developed using logistic regression. The 3D Slicer software was employed to manually delineate the region of interest (ROI) in the preoperative CT images, corresponding to the area of pyelohydronephrosis, for feature extraction. The optimal radiomic features were selected to construct radiomic models and calculate the radiomic score (Radscore). Subsequently, a combined clinical-radiomic model-the nomogram-was established by integrating the Radscore with independent risk factors. RESULTS: Univariate and multivariate logistic regression analyses identified cystatin C, Hounsfield Unit (HU) of pyonephrosis, history of ipsilateral urological surgery, and positive urine culture as independent risk factors for pyonephrosis (P < 0.05). Fourteen optimal radiomic features were selected from CT images to construct four radiomic models, with the Naive Bayes model demonstrating the best predictive performance in both training and validation sets. In the training set, the AUCs for the clinical model, radiomic model, and nomogram were 0.902, 0.939, and 0.991, respectively; in the validation set, they were 0.843, 0.874, and 0.959. Both calibration and decision curves showed good agreement between the predicted probabilities of the nomogram and the actual occurrences. CONCLUSION: The nomogram, constructed from CT radiomic features and clinical variables, provides an effective non-invasive predictive tool for pyonephrosis, surpassing both clinical and radiomic models.

Pyonephrosis complicated with spontaneous intraperitoneal rupture and diffuse peritonitis: Case report and literature review.

Pyonephrosis is a serious condition that can lead to kidney dysfunction, loss of the organ, and even fatal end due to its complications. The underlying etiologic factors include lithiasis, recurrent urinary infections, ureter stricture, ureteropelvic junction obstruction, malignancy, and retroperitoneal fibrosis. One of the rare possible complications of pyonephrosis is a retroperitoneal rupture with spontaneous communication to the abdomen causing secondary peritonitis. We present such a case which is the first video-documented report of the peritoneal rupture site within the abdominal cavity.

Psoas abscess in pregnancy: a review of the literature and suggestion of minimally invasive treatment options.

AIM: Less than a dozen cases of psoas abscesses in pregnancy have been described in the literature. We reviewed the literature when treating a patient with a psoas abscess after ipsilateral double J-ureteral stent placement (in the following: "double J-stent") due to infected hydronephrosis. METHODS: In January 2022, this review was searched using the Pubmed/MEDLINE database and the mesh terms "Psoas Abscess" AND "Pregnancy". Studies were included in any language and of all years, describing a psoas abscess during pregnancy. When patients did not have a psoas abscess, the abscess occurred after pregnancy, or when there was no full text available, the article was excluded. MAIN RESULTS: Ten case reports about patients with psoas abscesses during pregnancy were included. The classical symptomatic triad of psoas muscle abscess included lower back pain, limping and persistent fever with daily spikes. However, in most cases, not all three symptoms can be found. Especially, fever is absent in more than half of the patients. Psoas abscesses are described between 13 and 39 weeks of gestation. Primary psoas abscesses with haematogenous spread are more common during pregnancy than secondary with spread per continuitatem. In the literature, the main reasons for psoas abscess are spinal tuberculosis, drug abuse or underlying diseases such as Crohn's disease. It is not uncommon for the definite cause to be unclear. Regarding the patient's symptoms, pyelonephritis is often considered a possible aetiology. In general, the main treatment options include antibiotic treatment and abscess drainage. There is no higher caesarean section rate, and no negative outcome for the foetus has been described. CASE PRESENTATION: In our patient, a 38-year-old obese Caucasian woman, who had received a left double J-stent for infected hydronephrosis at 15 weeks of gestation, we successfully treated a psoas abscess of 20 × 10 cm with a sonographically assisted abscess drainage and antibiotics. The further course of pregnancy and the elective repeat caesarean section at 38 + 0 weeks of gestation were without any problems. Double J-stent placement and laser stone lithotripsy during puerperium were performed because of recurrent urolithiasis. CONCLUSIONS: Although rare, psoas abscesses can occur during pregnancy, and it has often been treated surgically in the past. A psoas abscess as a complication after infected hydronephrosis and intervention during pregnancy has never been reported in the literature. Even for obese patients, minimally invasive therapy may be a treatment option that has rarely been reported in the literature.

Mini-PCNL with a vacuum-assisted access sheath for renal calculi with pyonephrosis in the second stage.

OBJECTIVE: To compare the safety and efficacy of mini-PCNL with vacuum-assisted access sheath in the second-stage treatment of renal calculi with obstructive pyonephrosis. MATERIAL AND METHODS: A prospective, randomized clinical study was performed at our hospital from May 2020 to May 2022. Patients with pyogenic drainage fluid who needed percutaneous nephrolithotomy were randomized to the peel-away assisted mini-PCNL group (group A) and the vacuum-assisted mini-PCNL group (group B). Demographic information, clinical features, and perioperative period data were collected. RESULTS: Fifty mini-PCNLs using a single 16 F access sheath were performed in all patients of our study. All patients underwent second-stage surgical treatment. Demographic information and clinical features were not significantly different between groups A and B. But compared with group A, patients in group B had a short operative time (60.60 ± 7.68 min vs. 82.20 ± 14 min p = 0.018), a lower post-operative fever rate (8% vs. 32% p = 0.034), and a higher stone-free rate 2 d after the operation (88% vs. 64% p = 0.047). There was no significant difference between the two groups in blood transfusion, HB deficit, PCT after the operation, total hospitalization costs, stone-free rate 30 d after the operation, and length of stay or stay post-operative. And no serious complications after the operation occurred in either group. CONCLUSIONS: Mini-PCNL with vacuum-assisted access sheath is a safe and efficient treatment for patients with calculi-related obstructive pyonephrosis in the second stage.

One-stage tubeless percutaneous nephrolithotomy for asymptomatic calculous pyonephrosis.

BACKGROUND: In recent years, the safety and effectiveness of one-stage percutaneous nephrolithotomy (PCNL) for the treatment of calculous pyonephrosis have been proven. In order to further reduce postoperative pain and hospital stay, we first proposed and practiced the idea of one-stage tubeless percutaneous nephrolithotomy for calculous pyonephrosis. METHODS: A retrospective analysis was performed of case data of 30 patients with asymptomatic calculous pyonephrosis treated in our center with one-stage PCNL from January 2016 to January 2021. Patients were routinely given 20 mg of furosemide and 10 mg of dexamethasone sodium phosphate injection intravenously at the beginning of anesthesia. Among them, 27 patients successfully underwent one-stage tubeless percutaneous nephrolithotomy, while 3 cases were given indwelling nephrostomy tubes because of proposed second-stage surgery or the number of channels was greater than or equal to 3. All patients were operated on by the same surgeon. RESULTS: Preoperatively, 11 of 30 patients (8 men and 22 women) had positive urine bacterial cultures, and all were given appropriate antibiotics based on drug sensitivity tests. All patients completed the surgery successfully. The mean operative time was 66.6 ± 34.7 min, the mean estimated blood loss was 16.67 ± 14.34 mL and the mean postoperative hospital stay was 5.0 ± 3.1 days. The mean postoperative hospital stay was 4.6 ± 2.5 days among the 27 patients with one-stage tubeless percutaneous nephrolithotomy. Of the 3 patients with postoperative fever, 2 had the tubeless technique applied. One patient with 3 channels was given renal artery interventional embolization for control of postoperative bleeding. None of the 30 patients included in the study developed sepsis. The final stone-free rate was 93.3% (28/30) on repeat computed tomography at 1 month postoperatively. The final stone-free rate was 92.6% in the 27 patients undergoing one-stage tubeless percutaneous nephrolithotomy (25/27). CONCLUSIONS: One-stage tubeless PCNL is an available and safe option in carefully evaluated and selected calculous pyonephrosis patients.

A missed psoas abscess diagnosis: A forensic case report.

Psoas abscess is a rare pathology that usually presents with non-specific signs and rare clinical features. These characteristics can delay the diagnosis leading to complications and death. We report a forensic autopsy case of a 65-year-old male, alcoholic, smoker, with a history of hypertension, and urinary infection, who presented to the emergency room for anorexia and consciousness disorder. On physical examination, the patient was febrile and confused. Laboratory exams revealed leukocytosis and elevated C-reactive protein (CRP). Two days later, he died despite extensive resuscitation. Forensic autopsy revealed a large amount of green pus in the left psoas muscle extending to the muscles of the thigh of the same side with multiple cavities. The pus extended to the left kidney with destructive parenchyma and coralliform lithiasis. Histological examination showed destroyed renal tissue by lesions of chronic and acute pyelonephritis with dilatation of the pyelocaliceal cavities. Bacteriological analysis of the pus showed the presence of Escherichia coli. The psoas abscess was secondary to pyonephrosis favored by the immunodeficiency. Thus, death was attributed to a septic shock secondary to a psoas abscess complicating pyonephrosis.

Xanthogranulomatous Pyelonephritis with Pyonephrosis and Renal Abscess in a Young Adult: A Consequence of Neglected Urinary Tract Infection Leading to Nephrectomy.

Xanthogranulomatous pyelonephritis (XGP) is a rare form of chronic pyelonephritis, which is challenging to diagnose because its clinical presentation mimics other entities and is commonly associated with a history of urinary tract obstruction. We report a case of XGP in a young adult without nephrolithiasis and urinary tract obstruction. A 23-year-old woman presented with intermittent abdominal pain in the right upper quadrant persisting for the last ten months. The pain was dull, poorly localized, and started spreading to the right back, right shoulder, and right thigh in the last three months. Other complaints included fever, chills, pain during urination, and nausea. The patient had a history of infrequent urination, recurrent urinary tract infections (UTIs), and a low fluid intake. A physical examination revealed that the patient had right upper quadrant abdominal tenderness and right costovertebral angle tenderness. Laboratory findings showed leukocytosis and neutrophilia. The radiological examination revealed a round mass in the superior pole of the right kidney with mixed cystic and solid components, and a well-defined margin. It further enlarged from 4.5 cm to 10.6 cm in diameter in three months. The urologist performed a total right nephrectomy. The histopathological examination showed XGP with renal abscess. Proteus mirabilis was identified from the pus specimen culture. XGP should be considered in the diagnosis of patients having chronic UTI presented with or without the findings of urinary tract obstruction.

[A Case of Nephrocutaneous and Enterorenal Fistula Associated with Pyonephrosis].

A 57-year-old woman was referred to our hospital with a palpable mass in the left lumbar area. Computerized tomography revealed a diffusely enlarged destructed left kidney with impacted ureteropelvic junction stones and intense inflammatory stranding of the perirenal fat. This infiltration extended into the subcutaneous tissue. Since she refused to undergo nephrectomy, we performed transurethral ureterolithotripsy (TUL) two times. Retrograde ureterography before the third TUL showed communication between the renal pelvis and the jejunum. We performed a left-sided nephrectomy with a wedge resection of the jejunum. This is a rare case of nephrocutaneous and enterorenal fistula caused by pyonephrosis.

[A Case of Pyonephrosis Due to Urethral Stent Forgotten for 4 Years].

A 53-year-old woman had left pyonephrosis and bladder stone. A double-J ureteral stent was placed for left ureterostenosis and she was lost to followup. Five years later, she had back pain. Computed tomography revealed left hydronephrosis, pyonephrosis and bladder stone. After drainage by percutaneous nephrostomy and antibiotic treatment, left nephroureterectomy was performed. She has been free from recurrence of infection for 3 months after the surgery.

A Nautilus kidney.

We report a 71-year-old woman who presented with unilateral flank pain and sepsis. A computed tomographic (CT) scan demonstrated left-sided hydronephrosis. Subsequent percutaneous nephrotomy drainage showed pus-like material, confirming the diagnosis of pyonephrosis. The ureteral stricture was caused by previous radiation injury for cervical cancer in this ESRD patient who was on chronic dialysis for years. In our case, the grade IVB hydronephrosis is a result of an extremely atrophic kidney, pyonephrosis, and ureteral stricture. The CT section of pyonephrosis in an extremely atrophic kidney resembles a sagittal section of a Nautilus shell, as the shell corresponds to the diffusely thinned renal cortex.

Treatment of Pyonephritis Complicated by Septic Shock Using Extracorporeal Device Polymyxin B-Hemoperfusion.

Direct hemoperfusion using polymyxin B-immobilized fiber (PMX-DHP) is an established treatment method for septic shock caused by Gram-negative infections. We report one instance in which PMX-DHP therapy has been used successfully in a 33-year-old woman with septic shock from urosepsis. Although there is lack of recommendations in latest Surviving Sepsis Campaign Guidelines, evidence of PMX-DHP efficacy in this subset of patients is growing.

Challenges and management of laparoscopic treatment of pyonephrosis caused by calculi.

BACKGROUND: Calculous pyonephrosis is a disease characterized by infectious hydronephrosis associated with pyogenic destruction of the renal parenchyma, with complete or almost complete loss of renal function. METHODS: The clinical data of laparoscopic nephrolithotomy performed at Peking University People's Hospital from May 2017 to June 2020 were analyzed retrospectively. Eight patients (2 men; 6 women) aged 27 to 65 years (average age, 45.8 years) were included. Among them, 7 patients were treated with retroperitoneal approach and 1 patient by transperitoneal approach. All patients had received more than one endoscopic lithotripsy before nephrectomy. Renal dynamic imaging and computed tomography revealed the absence of function in pyonephrosis before nephrectomy. General clinical data and perioperative data were recorded. All nephrectomies were performed by the same physician. RESULTS: Laparoscopic surgery was successfully performed in 7 patients; however, 1 patient underwent open surgery because of bleeding. The operation time, average operation time, and blood loss were 1.5-4.5 h, 3.4 h, and 100-1000 ml (average, 300 ml), respectively. The postoperative pathology showed inflammatory renal disease in 6 patients, xanthogranulomatous pyelonephritis in 1 patient, and high-grade urothelial cancer in 1 patient. The average postoperative hospital stay was 5.3 days. One patient had a Clavien-Dindo Grade IIIb complication (severe hematuria), which required laparotomy, and was found that there was bleeding of ureteral stump. None of the patients experienced poor healing of endoscopic wounds. CONCLUSION: For patients with complicated calculous pyonephrosis, renal inflammation could not be effectively controlled, and renal function was seriously damaged. Thus, kidneys should be immediately resected. With laparoscopy, patients may recover quickly, but surgeons require enough experience when performing laparoscopy to achieve safety.

Urinary tract infection due to anaerobic bacteria in a two-month-old infant.

The significance of anaerobic bacteria as a pathogen in urinary tract infection (UTI) in children is unclear. A two-month-old infant presenting with poor feeding received a diagnosis of polymicrobial anaerobic UTI by next-generation sequencing and was found to have obstructive uropathy. Anaerobic bacteria may be a cause of UTI in children with urinary tract obstruction.

Risk factors and outcomes of urosepsis in patients with calculous pyonephrosis receiving surgical intervention: a single-center retrospective study.

BACKGROUND: Urosepsis is a catastrophic complication, which can easily develop into septic shock and lead to death if not diagnosed early and effectively treated in time. However, there is a lack of evidence on the risk factors and outcomes in calculous pyonephrosis patients. Therefore, this study was conducted to identify risk factors and outcomes of intra- and postoperative urosepsis in this particular population. METHODS: Clinical data of 287 patients with calculous pyonephrosis were collected. In the univariate and multivariate analysis, all patients were divided into urosepsis group and non-urosepsis group. The diagnosis of urosepsis was mainly on the basis of the criteria of American College of Chest Physicians (ACCP)/Society of Critical Care Medicine (SCCM). Patient characteristics and outcomes data were analyzed, and risk factors were assessed by binary logistic regression analysis. RESULTS: Of 287 patients, 41 (14.3%) acquired urosepsis. Univariate analysis showed that white blood cell (WBC > 10*10^9/L) before surgery (P = 0.027), surgery types (P = 0.009), hypotension during surgery (P < 0.001) and urgent surgery (P < 0.001) were associated with intra- and postoperative urosepsis for calculous pyonephrosis patients. In multivariate analysis, hypotension during surgery and urgent surgery were closely related to intra- and postoperative urosepsis. Outcome analysis suggested that patients developing urosepsis had a longer intensive care unit (ICU) stay and postoperative hospital stay and higher mortality. CONCLUSIONS: Hypotension during surgery and urgent surgery were risk factors of intra- and postoperative urosepsis for calculous pyonephrosis patients, which may lead to a prolonged ICU stay, postoperative hospital stay and higher mortality.

[Clinical analysis of 28 cases of calculous pyonephrosis undergoing B-ultrasound-guided renal puncture and drainage followed by secondary percutaneous nephrolithotomy].

Objective: To investigate the therapeutic effects of first phase renal puncture and drainage guided by B ultrasound and second phase percutaneous nephrolithotomy(PCNL) in the treatment of urinary calculi complicated with pyonephrosis. Methods: From January 2014 to April 2018, 28 patients with upper ureteral segment and kidney calculi complicated with pyonephrosis were collected. All patients received the pyonephrosis puncture under B ultrasound. After the inflammation was controlled and the clinical situation improved, the second phase was treated by PCNL. During the operation, routine in dwelling ureteral stent drainage and renal fistula wereperformed. The outcomes of the operation were observed. Results: A total of 28 cases were successfully punctured, the obstruction was relieved and the inflammation was controlled. Additionally, the second phase of PCNL surgery was successful, and there were no significant stone residues after PCNL. There were no complications such as severe systemic inflammatory response syndrome and severe hemorrhage. After 3 to 12 months of follow-up, renal function was restored to varying degrees, and there were no renal failure patients who needednephrectomy. Conclusions: Early diagnosis of urinary calculi complicated with pyonephrosis is the key to successful treatment. Active and effective B ultrasound-guided renal puncture and drainage, drainage of pus, and removal of urinary obstruction can improve the safety of the second phase of PCNL, and thus it attaches great importance to the treatment of pyonephrosis.

Laparoscopic nephrectomy outside gerota fascia and En bloc ligation of the renal hilum for management of inflammatory renal diseases.

OBJECTIVES: This study aims to improve laparoscopic nephrectomy techniques for inflammatory renal diseases (IRD) and to reduce complications. MATERIALS AND METHODS: Thirty-three patients underwent laparoscopic nephrectomy for IRD, with a method of outside Gerota fascia dissection and en-bloc ligation and division of the renal pedicle. Operative time, blood loss, complications, analgesia requirement, post-operative recovery of intestinal function and hospital stay were recorded. The degrees of perinephric adhesion were classified based on the observation during operation and post-operative dissection of the specimen, and the association of different types of adhesion with the difficulty of the procedures was examined. RESULTS: Among 33 cases, three were converted to hand-assisted laparoscopy, and one was converted to open surgery. Mean operative time was 99.6±29.2min, and blood loss was 75.2±83.5 mL. Postoperative recovery time of intestinal function was 1.6±0.7 days and average hospital stay was 4.8±1.4 days. By classification and comparison of the perinephric adhesions, whether inflammation extending beyond Gerota fascia or involving renal hilum was found to be not only an important factor influencing the operative time and blood loss, but also the main reason for conversion to hand-assisted laparoscopy or open surgery. CONCLUSIONS: In laparoscopic nephrectomy, outside Gerota fascia dissection of the kidney and en-bloc ligation of the renal pedicle using EndoGIA could reduce the difficulty of procedure and operative time, with satisfactory safety and reliability. Inflammation and adhesion extending beyond Gerota fascia or involving renal hilum is an important predictor of the difficulty related to laparoscopic nephrectomy for IRD.

Pyonephrosis as the first symptom of congenital hydronephrosis in a 6-year old girl.

Pyonephrosis in the course of hydronephrosis usually provides to total or near-total loss of renal function. In adults pyonephrosis usually results from urolithiasis. In children usually congenital urinary tract anomalies are present as contributing factors. CASE REPORT: 6-year old girl was admitted to the hospital because of 2-day history of high fever, abdominal pain, progressive deterioration of general condition and ultrasonographically (US) detected left hydronephrosis. US on admission showed grossly dilated left renal collecting system together with extensive echogenic debris and laboratory tests highly elevated inflammatory markers. Once diagnosis of pyonephrosis was established on the basis of clinical picture and US as well as laboratory tests results, nephrostomy tube was placed percutaneously. Pus culture obtained during placement of nephrostomy showed E.Coli ESBL (-) growth. Intensive antibiotic treatment (Meropenem) was continued for 3 weeks, nephrostomy was removed after 12 days after receiving normal urine. Further evaluation of urinary tract (US and computed tomography urography) showed large hydronephrosis due to ureteropelvic junction obstruction, while dynamic scintigraphy obstructive renogram with grossly diminished left kidney function to 20% of differential renal function. The girl was referred for operative treatment on urgent basis. Intraoperatively long distance utreteropelvic junction stenosis was found and dismembered Anderson- Hynes pyeloplasty was performed. During 2-years follow-up postoperatively US showed gradually decrease of dilatation of left renal collecting system, while dynamic scintigraphy revealed permanent improvement of drainage together with almost normal renal function (up to 45%). No urinary tract infections were noted. CONCLUSIONS: Proper management of pyonephrosis in hydronephrotic kidney due to congenital ureteropelvic junction obstruction enables good final result of treatment.

Computerized tomography attenuation values can be used to differentiate hydronephrosis from pyonephrosis.

PURPOSE: To determine the diagnostic value of computerized tomography (CT) in differentiating pyonephrosis from hydronephrosis on the basis of attenuation values (Hounsfield unit-HU). METHODS: Data of the patients with grades 1-3 hydronephrosis on abdominopelvic CT, who underwent nephrostomy tube placement for decompression of the collecting system, were retrospectively analyzed. Patient demographics and CT findings were recorded along with the first access urine culture results. Three physicians calculated the surface areas and the attenuation values of the dilated collecting systems using the system software. Mean HU of pyonephrosis and hydronephrosis cases was compared. RESULTS: A total of 105 patients with the mean age of 47.7 ± 15.5 (range 20-80) were included. The interclass correlation coefficient of three physicians was 0.981 for HU measurement and 0.999 for calculation of collecting system surface area. Of the patients, 47 (44.8 %) had pyonephrosis. Mean surface areas of the collecting system were similar in patients with pyonephrosis and hydronephrosis (1481.13 ± 1562.94 vs. 1612.94 ± 2261.4 mm2, p = 0.735). Urine cultures were positive in all patients with pyonephrosis, whereas 12.7 % of hydronephrosis cases had bacterial in first access urine culture. The HU of the patients with pyonephrosis was significantly higher that that of patients with hydronephrosis (13.51 ± 13.29 vs. 4.67 ± 5.37, p = 0.0001). Having a HU of 9.21 or over diagnosed pyonephrosis accurately with 65.96 % sensitivity and 87.93 % specificity. CONCLUSION: Measuring attenuation values of the collecting system may be useful to differentiate pyonephrosis from hydronephrosis. Diagnosing pyonephrosis accurately may avoid septic complications.

[A Case of Right Pyonephrosis Caused by Renal Pelvic Cancer].

A 47-year-old woman who was diagnosed with right pyelonephritis by a local physician, but failed to respond to antimicrobial chemotherapy, was referred to our hospital. Here, the diagnosis of right pyonephrosis was confirmed byabdominal computed tomography(CT). Retrograde pyelography(RP) revealed a severe stricture at the ureteropelvic junction, and it was considered difficult to advance a guidewire through the stricture. Urine cytologywas pseudo-positive ; thus, the possibilityof a malignant tumor of the urinarytract could not be ruled out. Therefore, right nephroureterectomywas performed. The final, histopathological diagnosis was urothelial carcinoma, (G2, pT3). After surgery, the signs and symptoms of the infection were rapidlyameliorated ; however, swelling of the lymph-nodes between the aorta and vena cava was observed, which was considered to be metastasis. Therefore, 4 courses of gemcitabine ＋cisplatin therapywere administered, which resulted in complete resolution of the lymph-node swelling. The patient has remained free of recurrence for 2 years after surgery.