Bilateral Ureteral Obstruction Research Articles

P35 Pyrexia of unknown origin in a patient with long standing rheumatoid arthritis

Abstract Introduction Pyrexia of unknown origin (PUO) can be challenging in treated rheumatic auto-immune disease. Many conditions may have fever as part of the symptom complex, treatment may mask signs and symptoms and can also make opportunistic infection more likely. Unusual or fastidious infections can be particularly difficult to diagnose. We describe a case of ureaplasma infection that evaded detection for a prolonged period in a female with long standing rheumatoid arthritis (RA). Case description 47 year old female presented January 2023 with fevers, weight loss and persistently high CRP. RA diagnosed in 1998. Erosive wrist and MTP disease, initial RF 32, CCP 8. Treatment- 5-10 mg prednisolone since 1998, adalimumab 2010, rituximab 2013-2022. Normal Ig levels, IgG lamda paraprotein since 2016 (too low to quantify). Frequency and dysuria March 2022. Cystoscopy- small bladder; biopsies in May 2022 and August 2023 showed acute on chronic inflammatory infiltrate with granulation tissue. Interstitial cystitis diagnosed. She had recurrent episodes of pyuria and was given several courses of antibiotics, including meropenem, temocillin, fluconazole, gentamicin. Despite the recurrent pyuria no organisms were cultured. CT CAP February 2023 -ground glass opacity right lower lobe. Later CXR clear. Quantiferon negative, also negative 2016, 2019. Other normal / negative tests- TTG, HIV, Hep ABCE, TFTs, EBV viral load. EBV, CMV IgG +ve. CMV titres 696 c/ml June 2023. CD 19 undetectable. IgG4 0.02 g/L. MPO, PR3 negative. BK virus was detected in urine. There was no sustained response to iv methylprednisolone and a course of filgotinib given for possible systemic RA symptoms. She developed a dry cough and shortness of breath. PET-CT July 2023 - bilateral FDG avid large confluent areas of consolidation. Urine + bronchial washings were negative for TB growth at 42 days. However, in view of deterioration empirical TB treatment was started July 2023. CT urogram in September 2023 showed likely bilateral renal abcesses, as well as bilateral hydronephrosis. Left renal cyst aspirate was performed and empirical doxycycline started at 100 mg bd. Ureaplasma detected from the aspirate on PCR. 3 weeks doxycyline given with rapid resolution of fevers and CRP. February 2024- cystectomy and ileal conduit in for refractory interstitial cystitis with a poorly compliant, small capacity, thick walled fibrotic bladder which had caused bilateral ureteric obstruction. She has made a good recovery. TB treatment course was completed. Discussion This case shows the difficulties in diagnosing infection from a little known and difficult to detect organism, ureaplasma. Discovered in the 1950s, it has no cell wall and very small genome and is therefore an obligate parasite /saprophyte. Together with mycoplasma it belongs to the bacterial class of Mollicutes. It cannot be routinely cultured nor gram stained. PCR or specialist culture is required. It may be present as a commensal but has been implicated in symptomatic genitourinary infections. It has also been implicated in native and non-native joint infections, and in infants can cause a pneumonic illness. Empirical treatment may be indicated due to long turn around times for diagnosis. There is some evidence that reduced humoral immunity may be a contributory factor to infection. We have found a previous case described of ureaplasma renal abcesses in a patient with MS and neurogenic bladder treated with rituximab. Our patient had normal immunoglobulin levels though still had profound CD19 suppression. Further immune suppression resulted from methylprednisolone and course of filgotinib, which may have accelerated the course of infection. Ureaplasma and mycoplasma do not have a cell wall, thus making beta-lactam antibiotics and vancomycin ineffective. Cyclines, josamycin and fluroquinolones are effective, though there is increasing resistance developing. We gave a relatively long course of doxycycline as our patient was very unwell and had apparent extensive urinary tract involvement. BK virus seropositivity is present in 90% of the normal population and asymptomatic viruria in up to 20%. However, it is a cause of renal tract inflammation in the immunosuppressed – in particular post-transplant. We felt it was unlikely to be significant in our patient in view of the clinical picture, lack of BK viraemia and negative viral findings on bladder biopsy. Key learning points • Ureaplasma should be on the list of organisms to consider in cases of PUO when the more common infective causes have been ruled out, particularly in immune suppressed patients. Patience and close collaboration with colleagues is essential. This patient had multiple MDT meetings involving infectious disease, respiratory, secondary and tertiary care urology and rheumatology specialists. The collaboration was invaluable. A course of doxycycline may be considered as a relatively low risk approach while awaiting microbiological confirmation in such cases.

The Effect of Nerolidol on Renal Dysfunction following Bilateral Ureteral Obstruction.

Background/Objectives: Obstructive uropathy is a common cause of renal impairment. Recently, there has been a burgeoning interest in exploring natural products as potential alternative remedies for many conditions due to their low toxicity, affordability and wide availability. Methods: We investigated the effect of nerolidol in a rat model of bilateral ureteral obstruction (BUO) injury. Nerolidol, dissolved in a vehicle, was administered orally as a single daily dose of 200 mg/kg to Wistar rats. Sham group (n = 12) underwent sham surgery, whereas the BUO (n = 12) and BUO/NR groups (n = 12) underwent reversible 24-h BUO and received the vehicle or nerolidol, respectively. The treatment started 9 days prior to the BUO/sham surgery and continued for 3 days after reversal. Renal functions were assessed before starting the treatment, just prior to the intervention and 3 days after BUO reversal. Results: Neither nerolidol nor the vehicle affected the basal renal functions. Nerolidol resulted in a significant attenuation in the BUO-induced alterations in renal functional parameters such as serum creatinine and urea, creatinine clearance and urinary albumin-creatinine ratio. Nerolidol also attenuated the changes in several markers associated with renal injury, inflammation, apoptosis and oxidative stress and mitigated the histological alterations. Conclusions: The findings of this study demonstrated the potent reno-protective effects of nerolidol in mitigating the adverse renal effects of bilateral ureteral obstruction. This is attributed to its anti-inflammatory, anti-fibrotic, anti-apoptotic and anti-oxidant properties. These effects were reflected in the partial recovery of renal functions and histological features. These findings may have potential therapeutic implications.

Successful endourological treatment for a rare case of atazanavir-induced urinary stones.

Atazanavir, an anti-HIV drug, induces urinary stone formation. We herein report a case of atazanavir-induced bilateral ureteral stones treated with endourological procedures. A 47-year-old male patient on atazanavir was admitted with right flank pain. The patient's serum creatinine level was 3.60 mg/dL. Plain computed tomography showed bilateral hydronephrosis. The left upper ureter was obstructed by a 13 × 12 × 9-mm mass, which had very low CT attenuation values. The lower part of the right ureter was obstructed, but no mass was observed. Given his medical history, we suspected bilateral ureteral obstruction caused by drug-induced stones. A ureteral stent was successfully inserted on the right side, but not on the left side. Thereafter, a bilateral ureteroscopic lithotripsy was performed. Infrared spectrophotometry revealed that the stone component was atazanavir. Understanding the characteristics of these rare drug-induced stones will aid in the proper early diagnosis and treatment.

Endoscopic diagnosis of an obstructive fungal ball in the urethra of a dog

AbstractA 1‐year‐old, male, neutered German shepherd dog was presented for a chronic atraumatic non‐healing fracture of the right accessory carpal bone, stranguria and polyuria/polydipsia. Biochemistry and urinalysis showed azotaemia. Ultrasound and computed tomography of the abdomen both demonstrated bilateral renal infarcts with pyelectasia, bilateral ureteral dilation and bladder distension. Cystoscopy of the bladder identified a fungal ball obstructing the pelvic urethral sphincter, which was adhered to the bladder mucosa in the region of the ureterovesicular junction. The obstruction was traversed endoscopically, but could not be removed transurethrally. The combination of elevated serum galactomannan titres (6.4) and Aspergillus terreus cultured from urine, confirmed a diagnosis of disseminated aspergillosis. The dog was euthanased due to poor quality of life, guarded prognosis and lengthy timeframe before an expected medical response. This is the first case report describing Aspergillus fungal balls in a dog causing partial urethral and bilateral ureteral obstruction, identified using cystoscopy.

Bilateral ureteral obstruction caused by a detrusor wall thickness: Case report and review of literature

Benign prostatic enlargement is a common condition in elderly men, caused by a histopathologic disease called benign prostatic hyperplasia. we report a case of a 76-year-old male with a benign prostatic hyperplasia who presented kidney injury due to bilateral hydronephrosis and no amelioration after bladder catheterization. An abdominopelvic computed tomography scan was performed showing bilateral moderate ureterohydronephrosis up to the level of the ureteral orifices within a diffuse thickening of the bladder wall and the endoscopic examination showed trigonal prominence, displacing and deforming the ureteral orifice. Three-months period of ureteral stenting with transurethral resection of prostate leads to significant improvement in renal function. This case underscores the importance of considering detrusor wall thickness as a potential cause of obstructive renal insufficiency, especially in elderly males presenting with chronic retention.

Rate of Post Obstructive Diuresis in Rapid Versus Gradual Bladder Decompression in Patients with Chronic Urinary Retention

Background: Post-obstructive diuresis (POD) is a polyuric state in which copious amounts of salt and water are eliminated after the relief of a urinary tract obstruction. POD is a clinical diagnosis based on urine output exceeding 200 mL per hour for two or more consecutives hours or 3L in 24 hours after decompressing an obstructed bladder, bilateral ureteric obstruction or unilateral ureteric obstruction in a solitary kidney. Methodology: This was a prospective, randomized study in which patients with chronic urinary retention were randomized into two groups: A and B. Group A had rapid urinary decompression with 18Fr urethral catheter attached to a urine bag, while group B had gradual decompression using a urethral catheter attached to an intravenous fluid giving set which was then attached to urine bag. Post obstructive diuresis in each group were assessed at designated times. Data Analysis and Result Presentation: Data was analyzed using the Statistical Package for Social Sciences (IBM) SPSS version 21. Data was summarized by descriptive statistics. The two arms were compared for similarities in demographic variables. Continuous and categorical variables were compared using student t- test and Pearsons‘ Chi – square respectively. Significant p value was 0.05. Result: Sixty patients were recruited into the study and randomized into group A (rapid urinary decompression) and B (gradual urinary decompression) with 30 patients in each group. Thirteen patients (43.33%) had post obstructive diuresis in group A compared to 15 patients (50%) in group B. p value of 0.584. Diuresis resolved within 24 hours in 9 patients (30%) in group A and 11 patients (36.7%) in group B. p value of 0.999. The mean reduction in systolic blood pressure was 8.21 ± 2.63mmHg in group A and 7.63 ± 2.14mmHg in group B. p value of 0.583. The mean reduction diastolic blood pressure was 3.84 ± 1.31mmHg in group A and 3.41 ± 1.16mmHg in group B. P value of 0.624. No patient in both groups developed hypotension (BP of <90/60). Conclusion: There was no statistically significant different in post obstructive diuresis. However, over 46.7% of patients had diuresis in both groups without any one developing hypotension. This may be due to routine prophylactic fluid and electrolyte replacement using normal saline.

Bilateral Ureteral Obstruction Caused by a Fecaloma: An Uncommon Presentation of Acute Kidney Injury

An 84 year-old woman with a history of hypertension, dyslipidemia, type 2 diabetes, atrial fibrillation, and diabetic kidney disease, presented with anorexia, oligoanuria, and constipation despite laxatives. The physical exam revealed a distended abdomen, and lab tests showed high creatinine levels only. The pre-renal etiology of the acute kidney injury was considered due to anorexia and probable dehydration. However, given the constipation mentioned in the clinical history, it was important to rule out a post-renal cause for the acute kidney injury, so an abdominal and pelvic CT scan was requested. The CT scan revealed small kidneys with ureters compressed by an 8 cm fecaloma, leading to acute renal failure due to post-renal obstruction (Figures 1 and 2). Laxative therapy was initiated, which resolved the fecaloma, and the patient was catheterized, resulting in the immediate release of 1 liter of urine. The resolution of the fecaloma and subsequent post-renal decompression led to a rapid recovery of kidney function.

Bilateral Ureteral Obstruction: Cause of AKI in Pregnancy

Bilateral Ureteral Obstruction: Cause of AKI in Pregnancy

Transcutaneous measurement of renal function in two rodent models of obstructive nephropathy

ObjectiveGlomerular filtration rate (GFR) is a key indicator of renal function. In both clinical practice and pre-clinical research, serum levels of endogenous filtration markers, such as creatinine, are often used to estimate GFR. However, these markers often do not reflect minor changes in renal function. In this study, we therefore set out to evaluate the applicability of transcutaneous GFR (tGFR) measurements to monitor the changes in renal function, as compared to plasma creatinine (pCreatinine), in two models of obstructive nephropathy, namely unilateral ureteral obstruction (UUO) or bilateral ureteral obstruction followed by release (BUO-R) in male Wistar rats.ResultsUUO animals showed a significant reduction in tGFR compared to baseline; whereas pCreatinine levels were not significantly changed. In BUO animals, tGFR drops 24 h post BUO and remains lower upon release of the obstruction until day 11. Concomitantly, pCreatinine levels were also increased 24 h after obstruction and 24 h post release, however after 4 days, pCreatinine returned to baseline levels. In conclusion, this study revealed that the tGFR method is superior at detecting minor changes in renal function as compared to pCreatinine measurements.

Hybrid Ureteroenteric Anastomosis Is Associated With Lower Stricture Rates in Ileal Conduit Urinary Diversion

BackgroundAnatomic complications of the ureteroenteric anastomosis in ileal conduit (IC) cause significant morbidity in patients post-cystectomy and cystoprostatectomy. The Bricker technique has a perceived disadvantage of increased risk for stricture, whereas the Wallace technique runs the risk for ureteral malignancy affecting both ureteric ends, and bilateral ureteric obstruction from a stone lodged at the anastomosis. We aimed to evaluate the safety, efficacy, and stricture rate of a novel hybrid ureteroenteric anastomosis technique. We compared these outcomes to the Bricker and Wallace anastomosis techniques for IC urinary diversion (ICUD).MethodsWe performed a retrospective chart review of patients who had undergone ICUD after cystectomy for bladder cancer from 2011 to 2016. Patients were categorized into groups undergoing the Bricker, Wallace, and hybrid ureteroanastomosic techniques. Strictures were identified during clinical follow-up or hospital presentations with complications.ResultsWe identified 68 patients suitable for inclusion. They were separated by Bricker, Wallace, and hybrid anastomosis techniques, with 19 (27.9%), 20 (29.4%), and 29 (42.6%) patients, respectively. Ureteroenteric anastomotic strictures occurred in 9 patients (5 Bricker, 3 Wallace, 1 hybrid). This difference in stricture rates for Bricker versus hybrid (26.3% vs. 3.4%; OR, 10 [95% CI, 1.1 to 121.1]; P = 0.02) was significant but was comparable for Wallace versus hybrid (15.0% vs. 3.4%; OR, 4.9 [0.7 to 66.0]; P = 0.15) and for Bricker versus Wallace (26.3% vs. 15.0%; OR, 2 [0.4 to 8.6]; P = 0.87). 15 patients (51%) in the hybrid group required oral antibiotics for a symptomatic urinary tract infection compared with 4 (21%) with Bricker and 8 (40%) with Wallace (P = 0.10). Median post-cystectomy follow-up and stricture formation time were 16 months (IQR, 4–36) and 9 months (7–32), respectively.ConclusionThe hybrid technique is a safe and efficacious alternative to the Bricker and Wallace anastomoses. It carries with it a risk for urinary tract infection that is eclipsed by substantially lowered rates of ureteric strictures requiring intervention while maintaining the advantage of separating the two ureters.

'Aquaporin-omics': mechanisms of aquaporin-2 loss in polyuric disorders.

Animal models of a variety of acquired nephrogenic diabetes insipidus (NDI) disorders have identified a common feature: all such models are associated with the loss of aquaporin-2 (AQP2) from collecting duct principal cells, explaining the associated polyuria. To discover mechanisms of AQP2 loss, previous investigators have carried out either transcriptomics (lithium-induced NDI, unilateral ureteral obstruction, endotoxin-induced NDI) or proteomics (hypokalaemia-associated NDI, hypercalcaemia-associated NDI, bilateral ureteral obstruction), yielding contrasting views. Here, to address whether there may be common mechanisms underlying loss of AQP2 in acquired NDI disorders, we have used bioinformatic data integration techniques to combine information from all transcriptomic and proteomic data sets. The analysis reveals roles for autophagy/apoptosis, oxidative stress and inflammatory signalling as key elements of the mechanism that results in loss of AQP2. These processes can cause AQP2 loss through the combined effects of repression of Aqp2 gene transcription, generalized translational repression, and increased autophagic degradation of proteins including AQP2. Two possible types of stress-sensor proteins, namely death receptors and stress-sensitive protein kinases of the EIF2AK family, are discussed as potential triggers for signalling processes that result in loss of AQP2. KEY POINTS: Prior studies have shown in a variety of animal models of acquired nephrogenic diabetes insipidus (NDI) that loss of the aquaporin-2 (AQP2) protein is a common feature. Investigations of acquired NDI using transcriptomics (RNA-seq) and proteomics (protein mass spectrometry) have led to differing conclusions regarding mechanisms of AQP2 loss. Bioinformatic integration of transcriptomic and proteomic data from these prior studies now reveals that acquired NDI models map to three core processes: oxidative stress, apoptosis/autophagy and inflammatory signalling. These processes cause loss of AQP2 through translational repression, accelerated degradation of proteins, and transcriptional repression.

A Comparative Study of 18F-FAPI-42 and 18F-FDG PET/CT for Evaluating Acute Kidney Injury in Cancer Patients.

Compare the value of imaging using positron 18F-labeled fibroblast activation protein inhibitor-42 (18F-FAPI-42) and 18F-labeled deoxyglucose (18F-FDG) for assessment of AKI. This study analyzed cancer patients who received 18F-FAPI-42 and 18F-FDG PET/CT imaging. Eight patients had AKI with bilateral ureteral obstruction (BUO), eight had BUO (CKD1-2) with no acute kidney disease (AKD), and eight had no ureteral obstruction (UO) with normal renal function. The average standardized uptake value (SUVave) of the renal parenchyma (RP-SUVave), the blood pool SUVave (B- SUVave), SUVave in the highest region of the renal collective system (RCS-SUVave), and the highest serum creatinine level (top SCr) were recorded. The 18F-FAPI-42 and 18F-FDG results showed that radiotracer of renal parenchyma was more concentrated in the AKI group than in the other two groups, whereas the RP-SUVave from 18F-FAPI-42 was higher than that from 18F-FDG in the AKI group (all P < 0.05). 18F-FAPI-42 imaging in the AKI group showed uptake by the renal parenchyma with a diffuse increase, but very little radiotracer in the renal collecting system, similar to a "super kidney scan." The renal parenchyma also had an increase of SUVave, with accumulation of radiotracer in the renal collecting system. AKI was more severe when a patient had a "super kidney scan" in both kidneys (P < 0.05). The B-SUVave level was higher in the AKI group than in the other two groups in 18F-FAPI-42 (both P < 0.05). 18F-FAPI-42 imaging had higher RP-SUVave than 18F-FDG imaging in cancer patients who had BUO with AKI. An increased renal parenchyma uptake in both kidneys and low radiotracer distribution in the collecting system suggest more severe AKI.

Serum creatinine trajectory after drainage of kidneys with bilateral malignant ureteral obstruction: a prospective non-randomized comparative study

BackgroundSerum creatinine trajectory (SCr-Tr) is a neglected prognostic tool for chronic and acute kidney injury. We aimed to assess the predictors of SCr-Tr during the time-to-nadir and serum creatinine (SCr) normalization rate after drainage, using percutaneous nephrostomy in patients with bilateral malignant ureteral obstruction.MethodsA prospective non-randomized study was performed on SCr-Tr in patients with bilateral malignant ureteral obstruction from August 2019 to March 2022. The primary outcome was SCr-Tr during the time-to-nadir.ResultsThis study included 102 patients with a mean age ± SD of 59.6 ± 14.7 years. SCr-Tr was non-linear with a mean ± SD (range) of 0.5 ± 0.4 (0.03–2.3) mg/dl/day. Multivariate analyses revealed that female gender (p = 0.016), body mass index (BMI; p = 0.005), and SCr at presentation (p < 0.001) were predictors of rapid SCr-Tr during the time-to-nadir. However, age (p = 0.008) and low urine output at presentation (p = 0.015) were associated with a lower SCr-Tr. In contrast, laterality of drainage (p = 0.544) and mean parenchymal thickness (p = 0.066) were not associated with mean SCr-Tr. Also, only the mean parenchymal thickness (p = 0.002) was a predictor of rapid SCr-Tr at ≥ 0.5 mg/dl/day. However, low BMI (p = 0.023) was associated with a high SCr normalization rate, while unilateral drainage (p = 0.045) was associated with a lower rate.ConclusionsFemale gender, low BMI, and SCr at presentation were predictors of rapid SCr-Tr during the time-to-nadir. Bilateral drainage was an independent predictor of SCr normalization rate, but not of rapid SCr-Tr. The mean parenchymal thickness was the only independent predictor for rapid SCr-Tr at ≥ 0.5 mg/dl/day.

3-Carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF) induces cell death through ferroptosis and acts as a trigger of apoptosis in kidney cells

Ferroptosis is a cell death mechanism characterized by intracellular iron accumulation and lipid peroxidation. Effects of uremic toxins on ferroptosis in the kidney are not well understood. We investigated whether protein-bound uremic toxins induce ferroptosis, resulting in cell death, using the bilateral ureteral obstruction (BUO) mouse model and kidney cells. In BUO mice, we observed elevated lipid peroxidation, increased iron concentration, and decreased glutathione peroxidase 4 (GPX4) expression. Levels of transferrin receptor 1 and system Xc-, which are involved in iron transport and storage, were also elevated, while those of ferritin heavy and light chains (FHC and FLC) were reduced. Treatment of HK-2 and NRK49F kidney cells with CMPF decreased GSH levels and the expression of GPX4, FHC, and FLC, and increased levels of ROS, lipid peroxidation, and intracellular iron concentration. CMPF-induced and erastin-induced decreases in GPX4 levels and increases in Bax and cytochrome C levels were counteracted by ferrostatin-1 pretreatment. However, GPX4 mRNA levels, protein abundance, or promoter activity were not restored by Z-VAD-FMK, a multi-caspase inhibitor. These results suggest that ferroptosis induced by CMPF treatment induces apoptosis, and inhibition of ferroptosis reduces apoptosis, suggesting that ferroptosis plays a role in triggering cell death by apoptosis.

Effects of hormone therapy on the clinical outcomes of endoscopic intervention in patients with endometriosis-related ureteral obstruction.

We investigated whether endoscopic interventions, including laser endoureterotomy and balloon dilatation following hormone therapy, are a good choice to treat ureteral obstruction due to ureteral endometriosis instead of laparoscopic or open surgery. Patients with ureteral obstruction due to endometriosis who underwent endoscopic intervention between 2004 and 2021 were reviewed. Patients with other causes of ureteral obstruction or previous ureteral surgery were excluded from the study. The primary endpoint was the 3-month success rate of endoscopic intervention with or without hormone therapy. Secondary endpoints were the success rate of endoscopic intervention between the hormone-treated and hormone-untreated groups at 6 months and the success rate according to the hormone therapy response of endometriosis at 3 and 6 months. Eighteen patients with 19 ureter units were evaluated in this study, including 12 patients receiving hormone therapy and six patients not receiving hormone therapy. Among patients receiving hormone therapy, one patient had bilateral ureteral obstruction. The success rate of endoscopic intervention was higher in patients who received hormone therapy than in those who did not receive hormone therapy three months after endoscopic intervention (76.9% vs. 0.0%, p=0.003). The same result was also found 6 months after endoscopic intervention (75.0% vs. 0.0%, p=0.005). In addition, the success rates were higher in the hormone-responsive group than in the non-responsive group (100.0% vs. 57.1%), although the difference was not statistically significant (p=0.122). Ureteral obstruction caused by endometriosis can be effectively treated by endoscopic intervention with hormone therapy in select patients.

Decreased absolute number of peripheral regulatory T cells in patients with idiopathic retroperitoneal fibrosis.

In order to determine whether the immune balance of T helper 17(Th17)/regulatory T(Treg) is related to the pathogenesis of idiopathic retroperitoneal fibrosis (IRPF), we analyzed the differences in peripheral blood lymphocytes, CD4+T cell subsets and cytokines between patients with IRPF and healthy people to clarify the CD4+T cell subsets, especially Treg cell subsets, and the role of cytokines in the pathogenesis of IRPF. This study included 22 patients with IRPF, 36 patients with IgG4-related diseases (IgG4-RD) without retroperitoneal fibrosis (RPF), and 28 healthy controls. The absolute numbers and percentage of peripheral blood lymphocyte subsets and CD4+T cell subsets in each group were detected by flow cytometry, and the serum cytokine level was detected by flow cytometric bead array (CBA). Compared with the healthy group, the absolute value of B cells in peripheral blood of IRPF patients was significantly decreased, and T, natural killer (NK), CD4+ and CD8+ were not significantly abnormal. The absolute numbers of Th2 cells were lower than healthy group(p=0.043). In particular, the absolute numbers of Treg cells were significantly lower than healthy group(p<0.001), while the absolute numbers of Th17 cells increased(p=0.682). Th17/Treg was significantly higher than healthy group (p< 0.001). Cytokine analysis showed that the level of interleukin (IL)-4 in IRPF patients was higher than healthy group(p=0.011), IL-6, IL-10, IL-17, TNF-α and IFN-γ were significantly higher than healthy group (all p<0.001). Receiver operating characteristic (ROC) curves showed that IL-10 and TNF-α could distinguish bilateral ureteral dilatation in IRPF patients, with areas under the ROC curve (AUCs) of 0.813 (95% CI:0.607-1.000, p=0.026) and 0.950 (95% CI:0.856-1.000, p=0.001), respectively. IL-6 could distinguish bilateral ureteral obstruction, with an AUC of 0.861 (95% CI: 0.682-1.000, p=0.015). Our study showed that IRPF patients had reduced Treg cells and indeed had Th17/Treg imbalance, which may be related to the pathogenesis of the disease. The levels of IL-6, IL-10 and TNF-α appear to be associated with the progression of IRPF.

Acute kidney injury due to bilateral malignant ureteral obstruction: Is there an optimal mode of drainage?

There is a well-known relationship between malignancy and impairment of kidney functions, either in the form of acute kidney injury or chronic kidney disease. In the former, however, bilateral malignant ureteral obstruction is a surgically correctable factor of this complex pathology. It warrants urgent drainage of the kidneys in emergency settings. However, there are multiple controversies and debates about the optimal mode of drainage of the bilaterally obstructed kidneys in these patients. This review addressed most of the concerns and provided a comprehensive presentation of this topic from the recent literature. Also, we provided different perspectives on the management of the bilateral obstructed kidneys due to malignancy. Despite the frequent trials for improving the success rates and functions of ureteral stents, placement of a percutaneous nephrostomy tube remains the most recommended tool of drainage due to bilateral ureteral obstruction, especially in patients with advanced malignancy. However, the disturbance of the quality of life of those patients remains a major unresolved concern. Beside the unfavorable prognostic potential of the underlying malignancy and the various risk stratification models that have been proposed, the response of the kidney to initial drainage can be anticipated and evaluated by multiple renal prognostic factors, including increased urine output, serum creatinine trajectory, and time-to-nadir serum creatinine after drainage.

The Case | An 80-year-old man with obstructive uropathy

An 80-year-old man was hospitalized for an acute kidney injury due to bilateral obstructive urolithiasis, with a creatinine serum level at 430 μmol/l. His past medical history revealed a renal colic 20 years ago, poorly controlled hypertension, obesity, type 2 diabetes treated with insulin, ischemic heart disease, ischemic stroke, and chronic kidney disease from unknown origin with a baseline serum creatinine value around 170 μmol/l. The abdominal computed tomography scan showed a bilateral ureteral obstruction caused by multiple stones.

S3599 Gastric Cancer Presenting With Bilateral Ureteral Obstruction

S3599 Gastric Cancer Presenting With Bilateral Ureteral Obstruction

Alteration of N6-methyladenosine epitranscriptome profiles in bilateral ureteral obstruction-induced obstructive nephropathy in juvenile rats.

Urinary tract obstruction is a common cause of renal failure in children and infants, and the pathophysiological mechanisms of obstructive nephropathy are largely unclear. It has been reported that m6A modulation is involved in renal injury. However, whether m6A RNA modulation is associated with obstructive nephropathy has not yet been reported. The aim of this study was to investigate the m6A epitranscriptome profiles in the kidneys of bilateral ureteral obstruction (BUO) in young rats. The total level of m6A in the kidneys was measured by liquid chromatography-tandem mass spectrometry. The mRNAs of related genes were detected by real-time PCR. Methylated RNA immunoprecipitation sequencing was performed to map the epitranscriptome-wide m6A profile. Global m6A levels were increased after BUO, and the mRNA expression levels of m6A methyltransferases and demethylases were significantly decreased in BUO group rat kidneys; the expression levels of EGFR and Brcal were significantly upregulated, while the mRNA expression levels of Notch1 were downregulated (P < 0.05). A total of 154 genes associated with 163 m6A peaks were identified. The m6A epitranscriptome was significantly altered in BUO rat kidneys, which is potentially implicated in the pathophysiological processes of obstructive nephropathy. The m6A RNA modification was associated with the process of renal injury in ureteral obstructive nephropathy by participating in multiple dimensions. The dysregulation of m6A methyltransferases and demethylases may be related to the pathophysiological changes of BUO-induced obstructive nephropathy. The m6A RNA modulation of the genes EGFR, Brca1, and Notch1 that were related to the regulation of aquaporin2 might be the potential mechanism for the polyuresis after ureteral obstruction.