Primary Ureteroscopy without Pre-Stenting for Proximal Ureteral Stones-Is It Feasible?

BACKGROUND: Primary ureteroscopy with laser lithotripsy is the treatment of choice for distal ureteral stones. However, in cases of proximal ureteral stones, some urologists recommend the preliminary insertion of a ureteral stent and deferred ureteroscopy. We aimed to evaluate the necessity of preliminary ureteral stent insertion in the management of proximal ureteral stones by comparing the surgical outcomes of patients undergoing primary ureteroscopy with laser lithotripsy for proximal vs. distal ureteral stones. METHODS: Medical records of patients who underwent ureteroscopy between 2016 and 2017 in our institution were retrospectively reviewed. Data collected included demographic data, stone size, renal function, intra- and post-operative complications, and stone-free rate (SFR). Patients were divided into two groups: proximal ureteral stones and distal ureteral stones. RESULTS: The cohort included 241 patients who underwent ureteroscopy. Among them, 106 had a proximal ureteral stone. The median age was 51 (IQR 41-65) years. Patients who underwent ureteroscopy for proximal ureteral stones were significantly older (p = 0.007). The median stone's maximal diameter was 7 (5-10) mm. The complication rate and stone-free rate (SFR) were similar in both groups (p = 0.657 and p = 1, respectively). The prevalence of post-procedural ureteral stent insertion was higher among patients who underwent ureteroscopy for proximal ureteral stones: 92.5% vs. 79.3% (p = 0.004). CONCLUSIONS: Our study concludes that primary ureteroscopy with laser lithotripsy for proximal ureteral stones is a valid and feasible treatment with a similar surgical outcome compared to distal ureteral stones. Preliminary ureteral stent insertion seems to be unnecessary.

Quality of life with tandem ureteral stents compared to percutaneous nephrostomy for malignant ureteral obstruction.

PURPOSE: Malignant ureteral obstruction (MUO) is treated with kidney decompression by a percutaneous nephrostomy (PCN) or internal ureteral stents. The objective of this study was to compare quality of life (QoL) with a PCN compared to tandem ureteral stents (TUS) in cases of MUO. METHODS: We reviewed the medical records of patients with MUO who were treated by PCN/TUS in our institution between June 2019 and May 2020. Patients were asked to fill out a QoL questionnaire, a tube-symptoms questionnaire, report a general health scale, and asked for a drain preference if they had experience with both drains. Scores of both groups were compared and predictors of all QoL and tube-symptoms measures were searched using multivariate analysis. RESULTS: Seventy-four patients with a PCN and 30 with TUS were included in the study. No statistically significant difference was found in all QoL and tube-symptoms measurements between the two drains. Type of drain was not found to be a predictor of QoL or tube-related symptoms. Eighty-four percent of patients (11/13) who have experience with both types of drains preferred TUS. CONCLUSION: TUS and PCN for relief of MUO have a negative and similar effect on various areas of QoL and urinary symptoms. Most patients who had experience with both types of drains preferred TUS over PCN. In this patient population with a grim prognosis, this negative effect must be communicated to patients, and calculated against the potential benefits of drainage.

[UPPER TRACT UROTHELIAL CARCINOMA].

INTRODUCTION: Upper tract urothelial carcinoma is a relatively rare malignancy, but with an increasing prevalence. The main risk factor for the disease is smoking. The most common presentation is hematuria or flank pain. Workup is made by imaging of the upper tract - CTU/MRU (Computed Tomography-Urography/Magnetic resonance (MR) urography) and diagnostic uretero-nephroscopy with biopsy. In the past several years there is major advancement in our understanding of the disease and how to treat it, mainly in nephron-sparing treatments. A risk-stratification is usually conducted according to parameters such as tumor size, distribution, and pathologic diagnosis. The low-risk group is usually offered nephron-sparing treatments such as segmental ureterectomy, endoscopic treatments, and lately - local chemotherapy. The high-risk group is usually offered radical resection of the kidney and ureter, with the possible addition of new-adjuvant and adjuvant treatments. In this article we will review the epidemiology, risk factors, diagnosis, and treatment of this malignancy, with a distinction between the risk groups.

A single day fasting may increase emergency room visits due to renal colic.

We aimed to explore whether a single-day of fasting (SDF) increase emergency room (ER) visits due to renal colic (RC). We elected to concentrate on Yom-Kippur (i.e.: SDF), the holiest day in Judaism. Food and liquid consumption is prohibited during this day for 25 h, and an estimated 50-70% fasting rate is observed. SDF always takes place between mid-September and mid-October during which the temperature in the Middle-East ranges between 19 and 30 °C. ER visits for RC between 01/2012 and 11/2019 were reviewed, and the Gregorian days on which SDF occurred were retrieved. The number of ER visits for RC was compared between SDF and the surrounding days/months as well as to another single-day "standard" holiday (SDSH) that precedes SDF in 10 days and is not associated with fasting. Of 11,717 ER visits for RC, 8775 (74.9%) were males. Male:Female ratio was 3:1. The mean daily number of ER visits for RC during the 3 days following SDF was 6.66 ± 2.49, significantly higher compared with the mean annual daily visits (4.1 ± 2.27, p < 0.001), the mean daily visits during the week prior to SDF (5.27 ± 2.656, p = 0.032), and the mean daily visits during September (5.06 ± 2.659, p = 0.005), and October (4.78 ± 2.23, p < 0.001). The mean number of ER daily visits for RC during the 3 days following SDSH, 5.79 ± 2.84, did not differ compared with the mean daily visits during September and October (p = 0.207; p = 0.13, respectively). It was lower compared to SDF, however statistically insignificant (p = 0.285). A single-day fasting may increase ER visits for RC. The mechanism underlying this phenomenon is unknown.

The Impact of Dietary Modifications and Medical Management on 24-Hour Urinary Metabolic Profiles and the Status of Renal Stone Disease in Recurrent Stone Formers.

BACKGROUND: Dietary modifications and patient-tailored medical management are significant in controlling renal stone disease. Nevertheless, the literature regarding effectiveness is sparse. OBJECTIVES: To explore the impact of dietary modifications and medical management on 24-hour urinary metabolic profiles (UMP) and renal stone status in recurrent kidney stone formers. METHODS: We reviewed our prospective registry database of patients treated for nephrolithiasis. Data included age, sex, 24-hour UMP, and stone burden before treatment. Under individual treatment, patients were followed at 6-8 month intervals with repeat 24-hour UMP and radiographic images. Nephrolithiasis-related events (e.g., surgery, renal colic) were also recorded. We included patients with established long-term follow-up prior to the initiation of designated treatment, comparing individual nephrolithiasis status before and after treatment initiation. RESULTS: Inclusion criteria were met by 44 patients. Median age at treatment start was 60.5 (50.2-70.2) years. Male:Female ratio was 3.9:1. Median follow-up was 10 (6-25) years and 5 (3-6) years before and after initiation of medical and dietary treatment, respectively. Metabolic abnormalities detected included: hypocitraturia (95.5%), low urine volume (56.8%), hypercalciuria (45.5%), hyperoxaluria (40.9%), and hyperuricosuria (13.6%). Repeat 24-hour UMP under appropriate diet and medical treatment revealed a progressive increase in citrate levels compared to baseline and significantly decreased calcium levels (P = 0.001 and 0.03, respectively). A significant decrease was observed in stone burden (P = 0.001) and overall nephrolithiasis-related events. CONCLUSIONS: Dietary modifications and medical management significantly aid in correcting urinary metabolic abnormalities. Consequently, reduced nehprolithiasis-related events and better stone burden control is expected.

Very low-dose computerized tomography for confirmation of urinary stone presence.

PURPOSE: To determine whether a modified non-contrast very low-dose computed tomography (VLD-CT) protocol is applicable for confirmation of known urolithiasis. METHODS AND MATERIALS: Consecutive adult patients with a CT scan showing urinary tract stone(s) between 6/2017-12/2018 were included. They were referred to a modified VLD-CT protocol if stone presence was equivocal or if stone location needed reassessment before an endourological interventional procedure. The scanned area was limited to the level of initial stone location caudally. Data on patients' demographics andbody mass index, were collected. The scanned length and radiation dose were calculated. Images were reviewed by two radiologists who assessed stone size and location. Follow-up reference standard included stone passage, surgical removal, and other imaging and clinical information. RESULTS: Sixty-three patients [63 stones, mean BMI 28.7 (range 19-41.9)] were included. VLD-CTs revealed 31 stones in 31 patients, with a mean stone length of 5.5 mm. Fifteen stones remained at the same location, and 16 had migrated, of which two appeared in the bladder. Thirty-two stones were not observed on VLD-CT. The mean span scanned on the VLD-CT was 274 mm (± 80). The average radiation exposure was 1.47 mGy (range 1.09-3.3), and the absorbed dose was 0.77 mSv (range 0.39-1.43), compared to 10.24 mGy (range 1.75-28.9) and 7.87 mSv (range 1.44-18.5) in the previous scan. The mean radiation dose reduction between scans was 89%. On follow-up, all VLD-CT findings were confirmed. CONCLUSION: A modified imaging protocol is applicable for confirmation of stone presence and location by utilizing very low-dose radiation exposure.

Endoscopic Treatment for Large Multifocal Upper Tract Urothelial Carcinoma.

PURPOSE: We reviewed the oncologic and surgical outcomes of endoscopic treatments for low grade upper tract urothelial carcinoma, and assessed the prognostic significance of tumor size, location and multifocality. MATERIALS AND METHODS: We retrospectively reviewed all patients who underwent endoscopic treatment for low grade upper tract urothelial carcinoma at our institution between 2014 and 2019. Tumors were treated with a dual laser generator, which alternately produces holmium and neodymium lasers. A stringent ureteroscopic followup protocol was conducted. We looked for an association between outcome and tumor size, location or multifocality, and for predictive factors for time to local recurrence and progression. RESULTS: The cohort included 59 patients (62 renal units), 27% of tumors were multifocal and 40% were >2 cm. The median followup time was 22 months (IQR 11-41), and the median number of ureteroscopies was 5.5 (4-9). Local recurrence was observed in 46 renal units (74.1%) at a median of 6.5 months after initial surgery. Four patients (6.4%) developed disease progression and were referred for radical surgery: 2 had pathological progression and 2 had a rapid and high volume local recurrence, and 1 later developed metastatic disease. The progression-free rate was 93.2%. Tumor location in kidney (p=0.03, HR 1.95) and multifocality (p=0.005, HR 3.25) significantly predicted time to local recurrence. No factor predicted time to progression. CONCLUSIONS: Ureteroscopic treatment of large, multifocal, low grade upper tract urothelial carcinoma is feasible, does not involve significant complications and has good short-term oncologic outcomes, with a 93.2% progression-free survival rate. Tumors located in the kidney and multifocality yielded shorter time to local recurrence but not progression.

Endoscopic management of upper tract urothelial carcinoma-tips and tricks.

Ureteroscopic methods have been rapidly evolving in the last several decades. With advances in flexible devices, optics and laser technologies, the endourologic surgeon has now the tools to treat high-volume tumors, in difficult locations, with good oncologic outcome. This makes radical nephroureterectomy unnecessary in some cases. Endoscopy in the setting of UTUC will surely continue to evolve and become applicable to a wider selection of patients. In this review we describe the surgical technique and provide tips and tricks which we use in our practice of endoscopic retrograde treatment of upper-tract urothelial carcinoma.

[THE EFFICACY OF ENDOSCOPIC DUAL LASER TREATMENT FOR LOW GRADE UPPER TRACT UROTHELIAL CARCINOMA].

INTRODUCTION: Until recently, radical nephroureterectomy was considered the gold standard treatment for upper tract urothelial carcinoma (UTUC). Post-operative complications, long-term adverse effects of nephrectomy as well as the risk of contralateral recurrence have led to the development of nephron-sparing techniques. OBJECTIVES: To evaluate the safety, complication rate, and oncologic outcomes of ureteroscopic nephron-sparing treatment for low-grade UTUC utilizing a hybrid laser system that incorporates two types of lasers: Nd:YAG and Ho:YAG. METHODS: We reviewed the files of patients who underwent ureteroscopic treatment for UTUC with the hybrid laser system between the years 2014-2018. Only cases of low-grade UTUC and follow-up time of at least 6 months were included in the present study. The following were analyzed: demographic data, tumor histologic characteristics, peri-operative complications, histologic upgrade, oncologic outcomes (i.e: local recurrence, local spread, metastatic progression). RESULTS: A total of 38 patients, who underwent 74 ureteroscopies, met inclusion criteria. Mean tumor size was 16.2 mm. No intra-operative complications were recorded. Two post-operative complications were recorded in one patient - hematuria and retroperitoneal bleeding - both had been treated conservatively. Mean follow-up time was 21.8 months. Local recurrence rate was 73%. Histologic upgrade has been observed in two patients. Four patients (10.5%) were referred to radical nephroureterectomy. There were no cases of local spread, distant metastases or death during the follow-up period. DISCUSSION: Endoscopic dual-laser treatment for low-grade UTUC is safe, surgically feasible and associated with good short-term oncologic outcome. Patient selection and strict follow-up are mandatory.

Tandem Ureteral Stents for Malignant Ureteral Obstruction.

Objectives: Malignant ureteral obstruction (MUO) is a devastating complication of cancer, and it is commonly treated by drainage via percutaneous nephrostomy (PCN). The objective of this study was to determine the efficacy, safety, and functional outcome of tandem ureteral stents (TUS) in the management of MUO. Materials and Methods: The medical records of all patients with MUO who underwent balloon dilation and TUS insertion in Sheba Medical Center between 2014 and 2018 were retrospectively analyzed. Safety was measured by intra- and postoperative complications, efficacy by time to event analysis, and failure by the requirement of PCN attributable to renal failure or infection. Independent risk predictors of TUS failure were determined by a multivariable Cox regression analysis. Results: A total of 103 procedures were performed on 81 patients during the study period. The median follow-up was 32 weeks (interquartile range [IQR] 24-67). Fifty-nine (72.9%) patients remained with TUS while 22 patients required PCNs. The median time to procedural failure was 4 months (IQR 2-8). Complications developed after 18 (22.2%) procedures. Two patients requested stent removal due to lower urinary tract symptoms. Independent predictors for TUS failure were metastasis (hazard ratio [HR] 3.03, 95% confidence interval [CI] 1.27, 7.23, p = 0.013) and prior PCN (HR 3.38, 95% CI 1.40, 8.13, p = 0.007). Conclusions: TUS is an efficient and safe management option for patients with MUO. It can alleviate renal failure without the need for an external PCN. Metastasis and prior PCN are associated with TUS failure.

[A COMPARISON BETWEEN TWO POTASSIUM CITRATE REGIMENS FOR THE TREATMENT OF NEPHROLITHIASIS].

BACKGROUND: UROCIT-K is a potassium-citrate regimen prescribed for the prevention of kidney stone formation. In 2013, K-CITEK was introduced to the local market as a new potassium-citrate regimen that reduces kidney stone formation in a declared rate of 93. OBJECTIVES: We sought to explore the efficacy of K-CITEK versus UROCIT-K. METHODS: A prospective database of patients treated with potassium-citrate regimens for nephrolithiasis has been reviewed. Patients were divided into two groups: those who were treated with UROCIT-K only (Group 1) and those who were treated with K-CITEK only (Group 2). The two groups were compared as regards to demographics, length of follow-up, urinary citrate level and stone burden changes, as well as the number of stone events (i.e: colic, surgery) throughout the follow-up period. In a separate analysis another group (Group 3) was checked. This group consisted of patients who were initially treated with UROCIT-K and later on were switched to K-CITEK. RESULTS: The study group consisted of 104 patients: 54 patients in Group 1, 38 in group 2 and 12 in group 3. The latter was omitted from analysis due to the small size. Groups 1 and 2 resembled in their demographic data and medical comorbidities. No statistically significant differences were found in terms of change in urinary citrate levels, stone burden or recurrent stone events. CONCLUSIONS: K-CITEK for the treatment of kidney stone prevention was found to be as equally effective as UROCIT-K in terms of increasing urinary citrate levels, reducing stone burden and maintaining the intervals between kidney stone events.

Is it safe to use a ureteral access sheath in an unstented ureter?

BACKGROUND: The aim of this study was to examine ureteral stricture rate after the use of UAS in an unstented ureter and compare complications of smaller vs. larger-caliber UAS. METHODS: We conducted a retrospective analysis of consecutive RIRS for renal stones, with the use of UAS in unstented ureters. We excluded cases with previous ureteroscopies, who carried ureteral stent or nephrostomy, had impacted stones, underwent radiation treatment, or had urinary tract malignancies. The primary outcome was formation of ureteral strictures diagnosed by hydronephrosis in ultrasound test and late secretion in dynamic renal scan. Secondary outcome was stone-free-rate (SFR) and complications. In addition, we compared safety and efficacy of smaller (9.5/11.5Fr) vs. larger-caliber (12/14Fr) UAS. RESULTS: The cohort included 165 patients with a median follow-up time of 115 days. There was no case of ureteral stricture formation after the use us UAS, despite using a larger-caliber UAS in nearly half the cases. Larger-caliber UAS was not associated with more complications compared to the smaller-caliber one (p = 0.780). SFR was non-significantly higher in the larger-caliber UAS group (p = 0.056), despite having a larger stone burden, and only stone number was associated with SFR (p = 0.003). CONCLUSIONS: These data suggest that the use of UAS during RIRS in an unstented ureter is safe and does not involve ureteral stricture formation after one procedure. Furthermore, the use of wider sheaths was not found to be associated with higher complications rate.

Practice patterns of ureteral access sheath during ureteroscopy for nephrolithiasis: a survey among endourologists worldwide.

BACKGROUND: The use of ureteral access sheath (UAS) during ureteroscopy is controversial. We aimed to explore practice patterns of UAS during ureteroscopy for nephrolithiasis among endourologists worldwide. METHODS: A 15-question survey was designed using the SurveyMonkey® platform. The questions covered the background and professional experience of the potential respondents, indications for UAS insertion, UAS caliber and possible complications associated with its use. The questions were anonymously tabulated in order to determine practice patterns of UAS during ureteroscopy for nephrolithiasis among endourologists. The survey was then distributed via e-mail to all the Endourological Society members. RESULTS: 216 members responded. 99.53% of the respondents practice as endourologists, 63.4% are fellowship trained and 74.4% are at least 6 years post-fellow. 73.2% practice in an academic facility. 77.3% perform at least 100 ureteroscopies annually. 46 and 76% routinely use UAS for the treatment of ureteral and kidney stones, respectively. In both cases, the 12/14 access sheath is the most common. 42% use UAS in primary ureteroscopy. 90.3% believe that a double J stent insertion is not mandatory prior to UAS insertion. 79.1% think the use of UAS does not increase postoperative complications rate, and if the latter does encounter, then most likely it is either a ureteral stricture (93.2%) or pain (48%). CONCLUSIONS: UAS is commonly used by highly skilled endourologists during ureteroscopy. 12/14 UAS is mostly used. Ureteral stricture and post-operative pain are proposed as possible complications following UAS introduction, however pre-stenting is not mandatory as overall low complication rate is expected.

24-h urine metabolic profile: is it necessary in all kidney stone formers?

PURPOSE: A 24-h urine metabolic profile (24-UMP) is an integral part of nephrolithiasis work-up. We aimed to explore whether it can be waived under certain circumstances. MATERIALS AND METHODS: We reviewed our prospective registry database of patients seen at our outpatient clinic for nephrolithiasis between the years 2010 and 2017. Data included: gender, age at first stone, body mass index (BMI), self-reported comorbidities and family history of nephrolithiasis. A 24-UMP was obtained from each patient under random diet. The following were recorded: urine volume, urinary levels of sodium, calcium, uric acid, oxalate and citrate. Presence of at least one comorbidity (i.e., hypertension/diabetes/hyperlipidemia) was defined as "associated comorbidities" (AC). Their absence was defined as "no comorbidities" (NC). Subjects were divided into two subgroups: first-time and recurrent stone formers, which were further divided into two subgroups: 1st + AC; 1st + NC; recurrent + AC; recurrent + NC. 24-UMPs have been compared between the four groups. RESULTS: Four hundred and fifty-seven patients were included in the study. In the AC groups, patients demonstrated higher BMI levels (p = 0.001), and were statistically significantly obese (BMI > 30, p = 0.001) and older at first stone event (p = 0.001). First formers, either with AC or NC were more likely to have low urine volume (LUV) compared with recurrent formers (72.5 vs. 59.5%, p = 0.005). In the remaining metabolic abnormalities, no such differences were observed. CONCLUSIONS: First-time stone formers, either with or without AC are likely to demonstrate LUV as their primary metabolic abnormality in 24-UMP. Therefore, 24-UMP may be postponed until recurrent stone event.

Urothelial-based reconstructive surgery for upper- and mid-ureteral defects: Long-term results.

INTRODUCTION: Ureteral strictures can result in obstructive nephropathy and renal function deterioration. Surgical management of ureteral defects, especially in the proximal- and mid-ureter, is particularly challenging. Our purpose was to analyze the long-term outcomes of urothelial-based reconstructive surgery for upper- and mid-ureteral defects. METHODS: We conducted a retrospective analysis of a single tertiary centre's database, including 149 patients treated for ureteral defects between 2001 and 2011. Thirty-one patients (21%) underwent complex urothelial-based surgical repairs for upper- and mid-ureter defects. Patients' median age was 61 years. The mean length of the ureteral strictures was 2.5 cm, located in upper-, mid-ureter, or in between in 19 (61%), 10 (32%), and two (6%) patients, respectively. All patients were treated with a primary urothelial-based repair. Median followup time was 26 months. The primary outcome of the study was the long-term preservation of renal function and lack of clinical obstruction. The secondary endpoint of the study was the assessment of the intra- and postoperative complication rates. RESULTS: Most of the lesions were benign (22, 71%), while nine strictures (29%) were malignant. Seven patients (23%) suffered from postoperative complications, five of which were infectious. The median pre- and postoperative calculated glomerular filtration rates were 66 ml/min/1.72m2 and 64ml/min/1.72m2, respectively. Success rate was 84%, defined as lack of need for re-operation or kidney drainage at the last followup. CONCLUSIONS: Upper- and mid-ureteral defects present a complex pathology necessitating experienced reconstructive surgical skills. Our data suggest good long-term results for primary urothelial-based reconstructions for these pathologies.

Can Unenhanced CT Findings Predict Interventional Versus Conservative Treatment in Acute Renal Colic?

OBJECTIVE: The purpose of this study was to determine the value of clinical parameters and radiologic findings on unenhanced CT to the choice between interventional and conservative management for patients with acute renal colic. MATERIALS AND METHODS: Unenhanced CT records of 183 consecutive patients with acute renal colic were retrospectively reviewed. Urolithiasis was confirmed at both unenhanced CT and clinical follow-up findings of 80 patients (study group). Clinical parameters (signs of infection and renal indexes) and unenhanced CT findings (tissue rim sign, hydronephrosis, perinephric and periureteral edema, ureteral dilatation, renal attenuation, and stone characteristics) were graded and correlated with the choice of clinical management. ROC analysis was constructed for the most statistically significant parameters. RESULTS: Forty-two patients (52%) were treated conservatively and 38 (48%) underwent interventional treatments. The relationship between shivering, fever, and leukocytosis and interventional treatment had low sensitivity (29%, 26%, and 16%, respectively) but very high specificity (98%, 95%, and 98%, respectively) (p < 0.05). Stone size and density were statistically significantly different between patients treated conservatively and those treated interventionally (size, 4.6 vs 6.7 mm; density, 730 vs 910 HU; p < 0.01). Stones larger than 6.5 mm with an attenuation value greater than 1100 HU and that were proximally located were more likely to be treated interventionally. CONCLUSION: Larger stone size, higher density, proximal location, and complaints of shivering, fever, and leukocytosis are the most important parameters for predicting invasive management of acute renal colic. Other clinical and radiologic information may be useful as supportive findings but do not predict the choice of patient management.

Nephrolithiasis in Israel: Epidemiological Characteristics of Return Patients in a Tertiary Care Center.

BACKGROUND: The prevalence and etiology of nephrolithiasis vary, depending on geography, gender and ethnicity. OBJECTIVES: To analyze the demographic data of return nephrolithiasis patients in a tertiary care center. METHODS: We retrospectively reviewed our prospective registry database of return patients seen at our outpatient clinic for nephrolithiasis. Data included gender, age at first visit, age at first stone event, body mass index (BMI), self-reported hypertension, diabetes mellitus (DM), and hyperlipidemia. All patients were seen at least twice and had undergone a metabolic workup. RESULTS: A total of 260 return patients were seen during the period 2010-2015. The male:female ratio was 3.1:1. Mean age at the first stone event was 44.1 years. Median time elapsed since the first stone event to medical evaluation was 5 years (interquartile range 1-12 years). Hypertension was reported by 33.1% of the patients, DM by 23.5% and hyperlipidemia by 30.4%. All three diseases were reported by 11.5% of patients. The metabolic abnormalities detected were hypocitraturia (60%), low urine volume (LUV) (60%), hypercalciuria (40.8%), hyperoxaluria (24.2%), hyperuricosuria (16.5%) and hyperuricemia (13.5%). Stone compositions from most to least frequent were calcium-oxalate (81%), calcium-phosphate (11.9%) and uric acid (7.1%). We also found that 24.6% were obese (BMI ≥ 30 kg/m2) and showed higher rates of hypertension, DM, hyperlipidemia, hyperuricemia and hyperuricosuria compared with non-obese patients. Significantly higher rates of obesity and LUV were detected in females compared with males. Patients over age 45 had lower rates of hyperuricemia compared with patients ≥ 45 years old (P = 0.038). CONCLUSIONS: Factors related to nephrolithiasis can potentially differ among populations and countries. Our findings emphasize the significance of individualized national health programs to address local issues.

Scrotal Hematoma Precipitated by Centrifuge Training in a Fighter Pilot with an Asymptomatic Varicocele.

BACKGROUND: Varicocele is quite common in the general population, affecting up to 15% of men. It is not considered disqualifying for the pilot's training program of the Israeli Air Force as long as there are no related symptoms or associated pathologies. During combat flight, increased venous pressure due to acceleration forces and anti-G straining maneuvers, used to counteract high gravitational G forces, can theoretically aggravate the venous blood pooling in varicocele, leading to rupture. CASE REPORT: We describe a case of a young fighter-jet pilot presenting with a painful inguinal hematoma extending to the scrotum a day after participating in centrifuge training. Sonographic examination demonstrated dilated spermatic veins and intratesticular varicocele along with subcutaneous thickening of the scrotal wall consistent with hematoma. DISCUSSION: The effects of high G loads on blood flow in spermatic veins, and especially in varicocele, still need to be determined. Varicocele rupture has been described in relation to increased intra-abdominal pressure and could theoretically occur during anti-G straining maneuvers. Such an acute adverse event during combat flight can be detrimental to flight safety and the pilot's well-being.

The relative contribution of urine extravasation to elevate plasma creatinine levels in acute unilateral ureteral obstruction.

INTRODUCTION: Rising levels of plasma creatinine in the setting of acute unilateral ureteral obstruction (AUUO) often reflects acute renal failure, mandating kidney drainage. We hypothesize that re-absorption of peri-renal urine extravasation (PUE), a common result of UUO, contributes significantly to the elevation in plasma creatinine, rendering the latter an inaccurate benchmark for renal function. We explored this hypothesis in a rat model of AUUO and PUE. METHODS: In total, 20 rats were equally divided into 4 groups. Groups 1 and 2 underwent unilateral ligation of the ureter with infiltration of rat's urine (index group) or saline (control) into the peri-renal space. Two additional control groups underwent peri-renal injection of either urine or saline without AUUO. Plasma creatinine levels were determined immediately prior to the procedure (T0), and hourly for 3 hours (T1, T2 and T3). Renal histology was investigated after 3 hours. RESULTS: Rats in the index group had a significantly greater increase in plasma creatinine levels over 3 hours compared to all other groups (p < 0.05). At T3, average plasma creatinine levels for the index group increased by 96% (0.49 ± 0.18 mg/dL) compared to 46% (0.23 ± 0.06 mg/dL increase) in the AUUO and saline group, and less than 15% rise in both the non-obstructed control groups. Our study limitations includes lack of spontaneous PUE and intraperitoneal surgical approach. CONCLUSIONS: Absorption of peri-renal urine in the presence of AUUO is a significant contributor to rising plasma creatinine levels, beyond those attributable to the obstruction alone, and may overestimate the extent of the true renal functional impairment.

Non-surgical treatment of latrogenic postoperatively diagnosed ureteral injuries.

BACKGROUND: latrogenic ureteral injury may be seen following abdominopelvic surgeries. While ureteral injuries identified during surgery should be immediately and surgically repaired, those that are postoperatively diagnosed may be treated non-surgically by draining the ipsilateral kidney. Data regarding the outcome of this approach are still missing. OBJECTIVES: To evaluate the success rates of non-surgical management of ureteral injuries diagnosed following abdominopelvic surgeries. METHODS: We retrospectively reviewed the files of all patients treated for iatrogenic ureteral injuries diagnosed following abdominopelvic surgeries. Patients' ipsilateral kidney was percutaneously drained following diagnosis of injury by either nephrostomy tube (NT)/nephro-ureteral stent (NUS) or double-J stent (DJS) inserted retrogradely. The tube was left in place until a pyelogram confirmed healing or a conservative approach was abandoned due to failure. RESULTS: Twenty-nine patients were identified as having ureteral injury following abdominopelvic surgery. Median time from injury to renal drainage was 9 days, interquartile range (IQR) 4-17 days. Seven cases (24%) had surgical repair. Among the other 22 patients, in 2 oncology patients the conservative approach was maintained although renal drainage failed to resolve the injury. In the remaining 20, median drainage length was 60 days (IQR 43.5-85). Calculated overall success rates following renal drainage was 69% (18/29), and with NUS approached 78.5%. CONCLUSIONS: Ureteral injuries diagnosed following abdominopelvic surgeries can be treated conservatively. Ipsilateral renal drainage should be the first line of treatment before surgical repair, and NUS may be the preferred drainage to obtain spontaneous ureteral healing.