Development of a radiomics model to discriminate ammonium urate stones from uric acid stones in vivo : A remedy for the diagnostic pitfall of dual-energy computed tomography

BACKGROUND

Dual-energy computed tomography (DECT) is purported to accurately distinguish uric acid stones from non-uric acid stones. However, whether DECT can accurately discriminate ammonium urate stones from uric acid stones remains unknown. Therefore, we aimed to explore whether they can be accurately identified by DECT and to develop a radiomics model to assist in distinguishing them.

METHODS

This research included two steps. For the first purpose to evaluate the accuracy of DECT in the diagnosis of uric acid stones, 178 urolithiasis patients who underwent preoperative DECT between September 2016 and December 2019 were enrolled. For model construction, 93, 40, and 109 eligible urolithiasis patients treated between February 2013 and October 2022 were assigned to the training, internal validation, and external validation sets, respectively. Radiomics features were extracted from non-contrast CT images, and the least absolute shrinkage and selection operator (LASSO) algorithm was used to develop a radiomics signature. Then, a radiomics model incorporating the radiomics signature and clinical predictors was constructed. The performance of the model (discrimination, calibration, and clinical usefulness) was evaluated.

RESULTS

When patients with ammonium urate stones were included in the analysis, the accuracy of DECT in the diagnosis of uric acid stones was significantly decreased. Sixty-two percent of ammonium urate stones were mistakenly diagnosed as uric acid stones by DECT. A radiomics model incorporating the radiomics signature, urine pH value, and urine white blood cell count was constructed. The model achieved good calibration and discrimination {area under the receiver operating characteristic curve (AUC; 95% confidence interval [CI]), 0.944 (0.899-0.989)}, which was internally and externally validated with AUCs of 0.895 (95% CI, 0.796-0.995) and 0.870 (95% CI, 0.769-0.972), respectively. Decision curve analysis revealed the clinical usefulness of the model.

CONCLUSIONS

DECT cannot accurately differentiate ammonium urate stones from uric acid stones. Our proposed radiomics model can serve as a complementary diagnostic tool for distinguishing them in vivo .

Prevention, diagnosis, and treatment of urolithiasis in geriatric patients - differences, similarities and caveats in comparison to the general population

PURPOSE OF REVIEW

Purpose of the review is to address management and prevention of urolithiasis in elderly patients examining the dynamic interplay between general measures, dietary adjustments, lifestyle modifications, and targeted pharmacological and/ or surgical interventions. The goal is to provide understanding of the evolving strategies required for effective urolithiasis prevention in the geriatric population.

RECENT FINDINGS

Age-specific diagnostic considerations are necessary because urolithiasis in the elderly population is characterized by bigger stones, greater peri-operative risks, and heightened symptom severity. When comorbidities are present, conservative treatments - especially analgesia - provide difficulties. Surgical procedures prove to be safe and effective, with complication rates and practical application comparable to younger cohorts. Prevention approaches that include lifestyle changes and the investigation of novel pharmaceutical options such as sodium-dependent glucose co-transporter 2 (SGLT-2)-inhibitors are promising in the management of urolithiasis in the elderly population.

SUMMARY

Our review offers a thorough investigation of urolithiasis in the elderly population, elucidating distinct clinical manifestations, complex diagnostic issues, and treatment implications. The safety and effectiveness of ureteroscopy in older patients, as well as the possible prophylactic function of SGLT-2-I, offer crucial insights for clinicians. Subsequent studies are necessary to enhance age-specific therapies, addressing the distinct obstacles presented by urolithiasis in the elderly population within this rapidly growing demographic.

[Prevention of recurrence of urolithiasis]

Urolithiasis is one of the most frequent urological diseases. Identifying the causes of stone formation forms the basis for successful prevention of recurrence. Metabolic diagnostics and measures for prevention of recurrence are based on the assignment of the patient to a low-risk or high-risk group. Analysis of the urinary calculi is an essential prerequisite for identifying patients at risk. The general recommendations on diet and lifestyle are considered to be the basis of treatment. Depending on the type of stone and the individual biochemical risk profile of a patient, these general measures should be supplemented by targeted medical nutrition therapy and pharmacological treatment. Mixed stones can pose a challenge for the treatment and prevention of recurrence. A personalized treatment decision that takes the various components of mixed stones into account could further improve the prevention of recurrence of urolithiasis.

Follow-up of urolithiasis patients after treatment: an algorithm from the EAU Urolithiasis Panel

OBJECTIVE

To develop a follow-up algorithm for urinary stone patients after definitive treatment.

MATERIALS AND METHODS

The panel performed a systematic review on follow-up of urinary stone patients after treatment (PROSPERO: CRD42020205739). Given the lack of comparative studies we critically evaluated the literature and reached a consensus on the follow-up scheme.

RESULTS

A total of 76 studies were included in the analysis, including 17 RCTs. In the stone-free general population group, 71-100% of patients are stone-free at 12 months while 29-94% remain stone-free at 36 months. We propose counselling these patients on imaging versus discharge after the first year. The stone-free rate in high-risk patients not receiving targeted medical therapy is < 40% at 36 months, a fact that supports imaging, metabolic, and treatment monitoring follow-up once a year. Patients with residual fragments ≤ 4 mm have a spontaneous expulsion rate of 18-47% and a growth rate of 10-41% at 12 months, supporting annual imaging follow-up. Patients with residual fragments > 4 mm should be considered for surgical re-intervention based on the low spontaneous expulsion rate (13% at 1 year) and high risk of recurrence. Plain film KUB and/or kidney ultrasonography based on clinicians' preference and stone characteristics is the preferred imaging follow-up. Computed tomography should be considered if patient is symptomatic or intervention is planned.

CONCLUSIONS

Based on evidence from the systematic review we propose, for the first time, a follow-up algorithm for patients after surgical stone treatment balancing the risks of stone recurrence against the burden of radiation from imaging studies.

Diagnosis and treatment of urolithiasis in a Toy Poodle dog

Background

Urolithiasis in dogs is a disorder of the urinary tract caused by the development of crystals. These crystals are composed of minerals such as phosphates, oxalates, urates, cystine, carbonates, and silica. It can be fatal if the diagnosis and treatment are inaccurate. This report aims to report a case of urolithiasis in a Toy Poodle dog.

Case Description

A 2-year-old male Toy Poodle dog weighing 4.2 kg with black hair, and having trouble urinating was presented to Prof. Soeparwi Animal Hospital, Universitas Gadjah Mada, Indonesia. The dog is examined physically and, in the laboratory, diagnosed and continued with operative therapy. The history and physical examination revealed that the dog had been experiencing hematuria, stranguria, and oliguria for 2 months, with the last few days accompanied by decreased appetite. The dog exhibited decreased skin turgor, a capillary refill time (CRT) of less than 2 seconds, signs of pain and distress during urination, and palpation of distended urinary vesicles. Ultrasound scans revealed uroliths in the urinary vesica, which were identified by an acoustic shadow. Blood tests indicated a decrease in hematocrit and erythrocytes along with an increase in leukocytes. Urolithiasis was diagnosed in the case dog based on anamnesis, physical examination, hematological examination, and ultrasonography. Subsequently, a cystotomy was performed, and uroliths located in urinary vesicles were removed. The dog received ceftriaxone injections at 15 mg/kg body weight and vitamin B-complex injections at a concentration of 10 mg/kg body weight for 5 days. Four days post-surgery, the case dog was able to successfully urinate and pass clean urine.

Conclusion

The Toy Poodle dog was diagnosed with silica urolithiasis in the urinary vesicles and the urolith is quite large. Cystotomy was performed to remove the urolith. Postoperative care were included the administration of antibiotics and vitamins to facilitate the healing process. The condition of the Poodle toy dog improved.

Simultaneous Detection of Citric Acid and Oxalic Acid Based on Dual Spectrum and Biomimetic Peroxidase for Urolithiasis Screening with a Fully Automatic Urine Analyzer

Urolithiasis stands as a prevalent ailment within the urinary system, with hyperoxaluria and hypocitraturia being the most frequent manifestations characterized by excessive oxalic acid (OA) and deficient citric acid (CA) levels in urine. Detecting these compounds in urine quantitatively holds paramount importance for early urolithiasis screening. Existing methodologies fall short in achieving simultaneous and on-site identification of OA and CA, posing challenges for accurate urolithiasis screening. Addressing this concern, the study successfully accomplishes the concurrent identification of OA and CA in urine through a combination of dual-spectral analysis and biomimetic peroxidase utilization. Bovine serum albumin and dithiothreitol-modified copper nanoclusters (BSA-DTT-CuNCs) are employed as biomimetic peroxidases, effectively mitigating interference and enabling the simultaneous determination of OA and CA. The quantification range spans from 0 to 12 mm for OA and 0.5 to 2.5 mm for CA, with detection limits of 0.18 and 0.11 mm, respectively. To facilitate swift and on-location urine analysis, a fully automated urine analyzer (FAUA) is introduced that streamlines the process of biomarker pretreatment and identification within urine samples. Validation with real urine samples from urolithiasis patients demonstrates the method's diagnostic precision, highlighting the dual-spectral technique and analyzer's promising role in urolithiasis screening.

Standardization of the management of pediatric urolithiasis in the emergency department

INTRODUCTION

The incidence of urolithiasis in the pediatric population is rising and medical expulsive therapy (MET) using alpha-adrenergic antagonists has been found to be effective in aiding in the passage of ureteral stones in children. A prior review of patients presenting to our quaternary children's hospital with urolithiasis found only 54 % were prescribed MET and these patients had increased rates of spontaneous stone passage. Thus, an ED urolithiasis management protocol was created to standardize evaluation and care of children with suspected urolithiasis.

OBJECTIVE

To compare management of children with urolithiasis presenting to the ED before and after urolithiasis management protocol implementation.

METHODS

This is a retrospective review of patients with urolithiasis who presented to our children's ED from 2011 to 2022. The primary outcome was rate of MET prescribing before and after pathway implementation in July 2017, thus the pre-implementation group comprises patients who presented to the ED from July 2011 to July 2017, and the post-protocol group includes those who presented from August 2017 to April 2022. Secondary outcomes included CT utilization in the ED, surgical intervention rate, proportion with spontaneous stone passage, and frequency of urology consultation. Two-sample t-test and Fisher's exact test were used to compare the outcomes of interest before and after protocol implementation.

RESULTS

Of 337 patients who presented to the ED after protocol implementation, 120 met inclusion criteria. When comparing outcomes before and after implementation of the protocol, there was significantly decreased use of CT scans (79 % vs 50 %, p < 0.0001) and increased prescribing of MET (54 % vs 82 %, p < 0.0001). There was a significant decrease in opioids prescribed (44 % vs 26.7 %, p = 0.0040), and an increased rate of spontaneous stone passage (34 % vs 46 %, p = 0.0483). Lastly, there was a significant reduction in the rate of surgery for stone management after the implementation of protocol (35 % vs 17 %, p = 0.0020) DISCUSSION: As the ED is the primary site of presentation for many children with urolithiasis, standardization of evaluation and management provides an opportunity to improve outcomes in this population. We found that implementation of an ED urolithiasis management protocol was associated with decreased use of CT scans, decreased opioid prescribing, increased spontaneous stone passage, and decreased rate of surgical management for children with ureteral stones.

CONCLUSIONS

This study demonstrates the positive impact of standardizing care for children presenting to the ED with urolithiasis.

Assessment of interleukin 17A and 23 in the course of bladder cancer and selected benign urological diseases

Several cytokines have been indicated to be significantly involved in urological diseases. Interleukin 17A (IL-17A) and interleukin 23 (IL-23) have recently received attention for their involvement in inflammatory diseases and cancers. The aim of the study was to show changes in the level of pro-inflammatory interleukins IL-17A and IL-23 in patients with bladder cancer (BC) and selected urological diseases. An important cognitive aspect was to study the interdependencies between the studied interleukins and to assess their diagnostic value for such diseases. The material for the study was urine sample from patients with BC, urinary tract infection (UTI), urolithiasis, benign prostatic hyperplasia (BPH), US (urethral stricture), which was compared to the urine sample of healthy people without urological disorders. Interleukin concentrations were measured by the immunoenzymatic method. The levels of IL-17A and IL-23 in the urine of patients with BC, UTI, BPH and US were significantly higher compared to the control group. Statistically significant differences were found in the level of both interleukins compared to the control group in all diseases except urolithiasis. IL-17A and IL-23 correlated with each other in patients with all urological diseases except urolithiasis. The results of the conducted studies showed that selected urological diseases changed the levels of IL-17A and IL-23 in the urine of patients. The observations made confirmed the participation of these interleukins in the course of the urological diseases, especially in BC, and allowed to classify them as potentially useful parameters for diagnostic purposes.

Evaluating the performance of ChatGPT in answering questions related to urolithiasis

PURPOSE

ChatGPT is an artificial intelligence (AI) program with natural language processing. We analyzed ChatGPT's knowledge about urolithiasis whether it can be used to inform patients about urolithiasis.

METHODS

Frequently asked questions (FAQs) about urolithiasis on the websites of urological associations and hospitals were analyzed. Also, strong recommendation-level information was gathered from the urolithiasis section of the European Association of Urology (EAU) 2022 Guidelines. All questions were asked in order in ChatGPT August 3rd version. All answers were evaluated separately by two specialist urologists and scored between 1 and 4, where 1: completely correct, 2: correct but inadequate, 3: a mix of correct and misleading information, and 4: completely incorrect.

RESULTS

Of the FAQs, 94.6% were answered completely correctly. No question was answered completely incorrectly. All questions about general, diagnosis, and ureteral stones were graded as 1. Of the 60 questions prepared according to the EAU guideline recommendations, 50 (83.3%) were evaluated as grade 1, and 8 (13.3%) and 2 (3.3%) as grade 3. All questions related to general, diagnostic, renal calculi, ureteral calculi, and metabolic evaluation received the same answer the second time they were asked.

CONCLUSION

Our findings demonstrated that ChatGPT accurately and satisfactorily answered more than 95% of the questions about urolithiasis. We conclude that applying ChatGPT in urology clinics under the supervision of urologists can help patients and their families to have better understanding on urolithiasis diagnosis and treatment.

Carbon dots and MnO2 nanosheet nanocomposites sensing platform for sensitive detection of oxalate in urine samples of urolithiasis patients

In the human body, oxalate tends to form calcium oxalate with calcium ions, which can trigger the formation of stones in the urinary system. Therefore, oxalate in urine is usually utilized as a crucial biomarker in clinical urolithiasis diagnoses. In this work, a turn-on fluorescent nanoprobe was developed based on nitrogen-doped carbon dots (N-CDs) and MnO2 nanosheets (NSs) nanocomposites for oxalate sensing in urolithiasis patients. MnO2 NSs is a good sensing platform with high extinction coefficients and rich redox chemistry. The fluorescent N-CDs can be quenched efficiently by MnO2 NSs through the inner filter effect (IFE) to form N-CDs-MnO2 nanocomposites. The reductive oxalate could operate the decomposition of MnO2 NSs to Mn2+ resulting in the dissociation of the N-CDs-MnO2 nanocomposites and fluorescence recovery of N-CDs. Under optimal conditions, the developed sensor revealed good specificity toward oxalate with a limit of detection (LOD) of 0.69 μM. The developed sensor was successfully applied to quantify oxalate content in 47 urine samples (41 urolithiasis patients and 6 healthy persons). The results showed great consistency with clinical diagnostic reports and computed tomography images. This novel method retains several unique advantages, including affordable, rapid, and validating potential clinical application.

The Association of Urolithiasis with Uricosuria, Uricemia and their Combination

BACKGROUND

There are conflicting data on the significance of hyperuricemia or hyperuricosuria in urolithiasis formation and on the need for medical treatment.

OBJECTIVES

To assess the significance of hyperuricemia or hyperuricosuria in urolithiasis formation, particularly when hyperuricemia occurs with normal uricosuria.

METHODS

The electronic medical records of patients treated in Haifa and the Western Galilee district of Clalit Health Services, Israel, were retrospectively screened for diagnosis of nephrolithiasis or renal or urinary tract/bladder calculi between February 2014 and April 2019. The diagnosis was confirmed by ultrasonography or computed tomography. The study group included patients with one of these diagnoses. Patients in the control group did not have these diagnoses. The inclusion criterion for all patients was the presence of both serum and urinary uric acid levels.

RESULTS

The study group included 359 patients and the control group 267. After adjustment by logistic regression, we found no significant differences in the prevalence of hyperuricosuria in the study group (14.8%) compared to the control group (9.7%), odds ratio (OR) 1.54 (95% confidence interval [95%CI] 0.74-3.2, P = 0.245). No significant differences between the groups were observed for hyperuricemia prevalence (45.4% vs. 55.1%, respectively, OR 0.82, 95%CI 0.54-1.25, P = 0.355), nor among those without hyperuricosuria (OR 0.83, 95%CI 0.52-1.33, P = 0.438) and after propensity score matching (OR 0.93, 95%CI 0.66-1.3, P = 0.655).

CONCLUSIONS

There were no significant differences in hyperuricemia or hyperuricosuria between the two groups of patients or in hyperuricemia among participants without hyperuricosuria.

High risk and low prevalence diseases: Infected urolithiasis

INTRODUCTION

Infected urolithiasis is a serious condition that carries with it a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of infected urolithiasis, including presentation, diagnosis, and management in the emergency department based on current evidence.

DISCUSSION

Although urolithiasis is common and the vast majority can be treated conservatively, the presence of a concomitant urinary tract infection significantly increases the risk of morbidity, to include sepsis and mortality. Identification of infected urolithiasis can be challenging as patients may have symptoms similar to uncomplicated urolithiasis and/or pyelonephritis. However, clinicians should consider infected urolithiasis in toxic-appearing patients with fever, chills, dysuria, and costovertebral angle tenderness, especially in those with a history of recurrent urinary tract infections. Positive urine leukocyte esterase, nitrites, and pyuria in conjunction with an elevated white blood cell count may be helpful to identify infected urolithiasis. Patients should be resuscitated with fluids and broad-spectrum antibiotics. Additionally, computed tomography and early urology consultation are recommended to facilitate definitive care.

CONCLUSIONS

An understanding of infected urolithiasis can assist emergency clinicians in diagnosing and managing this potentially deadly disease.

Adenine phosphoribosyl transferase (APRT) deficiency and a novel sequence variant in APRT with phenotypic diversity and a literature review

Adenine phosphoribosyl transferase (APRT) deficiency is an autosomal recessive disorder and a rare cause of urolithiasis due to mutations in APRT (OMIM #102600). APRT deficiency results in increased urinary excretion of 2,8-dihydroxyadenine (DHA) which can cause urolithiasis and kidney failure. However, with prompt diagnosis, patients with APRT deficiency can be treated with xanthine oxidoreductase inhibitors which decrease urinary DHA excretion and improve outcomes. We report a pair of siblings, an 11-year-old brother and his 14-year-old sister with compound heterozygous variants c.270del (p.Lys91Serfs*46) and c.484_486del (p.Leu162del) in APRT with variable clinical presentation of APRT deficiency. The brother presented at 17 months of age with urolithiasis and severe acute kidney injury. His elder sister remained well and asymptomatic with normal kidney function and did not develop renal calculi. Brownish disk or sphere-like crystals with both concentric and radial markings were reported on urine microscopy in the sister on screening. The sister's diagnosis was confirmed with further laboratory evidence of absent red cell lysate APRT activity with corresponding elevated levels of urinary DHA. In conclusion, we identified a novel mutation in the APRT gene in a pair of siblings with greater phenotypic severity in the male.

2022 Recommendations of the AFU Lithiasis Committee: Management of symptomatic urinary stones

The acute situation, caused by an obstructive stone, is defined by a renal colic that may be uncomplicated, complicated, or at risk in specific conditions. Its management may be medical or require interventional treatment by extracorporeal shockwave lithotripsy, endoscopic removal, or ureteroscopy. METHODOLOGY: These recommendations were developed using two methods, the Clinical Practice Recommendations (CPR) and the ADAPTE method, in function of whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis) [EAU Guidelines on urolithiasis. 2022] and whether they could be adapted to the French context.

2022 Recommendations of the AFU Lithiasis Committee: Specific cases - chronic kidney disease, bilateral stones, and solitary kidney

Chronic kidney disease, diabetes and hypertension are risk factors of kidney function impairment. The relative risk of kidney failure is 1.52 in patients with urinary stone disease. The various techniques used to remove upper urinary tract stones generally do not alter kidney function in patients with normal kidney function and may sometimes improve kidney function or slow its deterioration in patients with kidney disease. Compared to the asynchronous treatment of bilateral renal and ureteral stones, concomitant treatment is associated with higher risk of anuria and the need of additional interventions, in the absence of postoperative stenting. For the treatment of solitary kidney stones, the absence of postoperative stenting increases the risk of postoperative anuria. Moreover, the multiplication of percutaneous nephrolithotomy access tracts increases the risk of bleeding and that of kidney function impairment. METHODOLOGY: These recommendations were developed according to two methods: the Clinical Practice Recommendations (CPR) method and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis) [EAU Guidelines on urolithiasis. 2022] and their adaptability to the French context.

2022 Recommendations of the AFU Lithiasis Committee: Medical management - from diagnosis to treatment

The morphological-compositional analysis of urinary stones allows distinguishing schematically several situations: dietary, digestive, metabolic/hormonal, infectious and genetic problems. Blood and urine testing are recommended in the first instance to identify risk factors of urinary stone disease in order to avoid recurrence or progression. The other objective is to detect a potential underlying pathology associated with high risk of urinary stone disease (e.g. primary hyperparathyroidism, primary or enteric hyperoxaluria, cystinuria, distal renal tubular acidosis) that may require specific management. Lifestyle-diet measures are the basis of the management of all stone types, but pharmacological treatments may be required. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendation (CPR) method and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis) [EAU 2022] and their adaptability to the French context.

[Report template from the German Society of Urology and the German Radiological Society for standardized, structured reporting of native computed tomography scans in the diagnosis of urinary stones]

Standardized structured radiological reporting (SSRB) has been promoted in recent years. The aims of SSRB include that reports be complete, clear, understandable, and stringent. Repetitions or superfluous content should be avoided. In addition, there are advantages in the presentation of chronological sequences, tracking and correlations with structured findings from other disciplines and also the use of artificial intelligence (AI)-based methods. The development of the presented template for SSRB of native computed tomography for urinary stones followed the "process for the creation of quality-assured and consensus-based report templates as well as subsequent continuous quality control and updating" proposed by the German Radiological Society (DRG). This includes several stages of drafts, consensus meetings and further developments. The final version was published on the DRG website ( www.befundung.drg.de ). The template will be checked annually by the steering group and adjusted as necessary. The template contains 6 organ domains (e.g., right kidney) for which entries can be made for a total of 21 different items, mostly with selection windows. If "no evidence of stones" is selected for an organ in the first query, the query automatically jumps to the next organ, so that the processing can be processed very quickly despite the potentially high total number of individual queries for all organs. The German, European, and North American Radiological Societies perceive the establishment of a standardized structured diagnosis of tomographic imaging methods not only in oncological radiology as one of the current central tasks. With the present template for the description of computed tomographic findings for urinary stone diagnostics, we are presenting the first version of a urological template. Further templates for urological diseases are to follow.

2022 Recommendations of the AFU Lithiasis Committee: Endoscopic description of renal papillae and stones

Endoscopic observation is performed during treatments by flexible ureteroscopy to differentiate in situ between renal papillary abnormalities and stones based on their concordance with Daudon's morphological/composition descriptions adapted to endoscopy. These intraoperative visual analyses are now an integral part of the urinary stone disease diagnostic approach in addition to the morphological/structural and spectrophotometric analysis that remains the reference exam, but that loses information on the stone component representativeness due to the development of in situ laser lithotripsy. These are the first practical recommendations on the endoscopic description of renal papillae and stones. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendations (CPR) and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis [EAU Guidelines on urolithiasis. 2022]) and their adaptability to the French context.

2022 Recommendations of the AFU Lithiasis Committee: Epidemiology, stone analysis and composition

The incidence of urinary lithiasis is rising steadily in industrialized countries, and its prevalence in the general population of France is estimated at 10%. Renal colic accounts for 1-2% of emergency department consultations. At a time when the new LASER stone fragmentation techniques available to urologists will lead to ever finer in situ pulverization of stones, the exact identification of the compounds that form the stone is essential for etiological diagnosis. Constitutional analysis by infrared spectrophotometry or X-ray diffraction is therefore recommended, to be complemented by morphological typing of the calculi. METHODOLOGY: These recommendations have been drawn up using two methods: the Recommendation for Clinical Practice (RPC) method and the ADAPTE method, depending on whether or not the issue was considered in the EAU recommendations (https://uroweb.org/guidelines/urolithiasis) [EAU 2022] and their adaptability to the French context.

[Imaging for urolithiasis]

The substantial reduction of radiation exposure using (ultra-)low dose programs in native computed tomographic imaging has led to considerable changes in imaging diagnostics and treatment planning in urolithiasis in recent years. In addition, especially in Germany, ultrasound diagnostics is highly available in terms of equipment and with increasing expertise. This can largely replace the previous radiation-associated procedures in emergency and follow-up diagnostics, but also in intraoperative imaging, e.g., in percutaneous stone therapy (intraoperative fluoroscopy). This is reflected in the international guidelines, which recommend these two modalities as first-line diagnostics in all areas mentioned. Continuous technical development enables ever higher resolution imaging and thus improved diagnostics with high sensitivity and specificity. This also enables reliable imaging of particularly vulnerable patient groups, such as children or pregnant women. In addition, methods from the field of artificial intelligence (AI; machine learning, deep learning) are increasingly being used for automated stone detection and stone characterization including its composition. Furthermore, AI models can provide prognosis models as well as individually tailored treatment, follow-up, and prophyaxis. This will enable further personalization of diagnostics and therapy in the field of urolithiasis.

Comprehensive prediction of urolithiasis based on clinical factors, blood chemistry and urinalysis: UROLITHIASIS score

Comprehensive prediction of urolithiasis using available factors obtained in the emergency department may aid in patient-centered diagnostic imaging decisions. This retrospective study analyzed the clinical factors, blood chemistry and urine parameters of patients who underwent nonenhanced urinary computed tomography for suspected urolithiasis. A scoring system was developed from a logistic regression model and was tested using the area under the curve (AUC). The prevalence of urolithiasis and important possible causes in the three risk subgroups were determined. Finally, the scoring model was validated. In the derivation cohort (n = 673), 566 patients were diagnosed with urolithiasis. Age > 35 years, history of urolithiasis, pain duration < 8 h, nausea/vomiting, costovertebral angle tenderness, serum creatinine ≥ 0.92 mg/dL, erythrocytes ≥ 10/high power field, no leukocytes ≤  + , and any crystalluria were retained in the final multivariable model and became part of the score. This scoring model demonstrated good discrimination (AUC 0.808 [95% CI, 0.776-0.837]). In the validation cohort (n = 336), the performance was similar (AUC 0.803 [95% CI, 0.756-0.844]), surpassing that of the STONE score (AUC 0.654 [95% CI, 0.601-0.705], P < 0.001). This scoring model successfully stratified patients according to the probability of urolithiasis. Further validation in various settings is needed.

REPRESENTATION OF KIDNEY DAMAGE AT THE MOLECULAR LEVEL IN PATIENTS WITH UROLITHIASIS BASED ON THE STUDY OF ENZYMATIC TEST INDICATORS

The aim of the work is to improve the results of early diagnosis of acute infectious kidney diseases at the molecular level in urolithiasis (urinary stone disease) through the study of enzymatic test indicators. Enzymatic tests (NGAL, IL-1β, β2-microglobulin) were investigated at the molecular level using the IFA method in the urine of patients with urolithiasis. Comparative and prognostic significance of the conducted treatment was established between the groups of patients, and an algorithm was developed based on the results of kidney damage predictors. It was found that the indicators of general laboratory analysis in patients with urolithiasis within the first 24-48 hours do not reliably indicate the absence of an infectious-inflammatory process in the kidneys and the development of renal failure. It was determined that an increase in the inflammation predictor indicators in more than 50% of patients indicates the development of infectious-inflammatory complications within the first 12-24 hours before the occurrence of general laboratory and clinical changes. The assessment of the effectiveness of conservative therapy in groups IA and II revealed that complications of the inflammatory process in the kidneys were observed five times more frequently in group II (comparison) than in group IA. The use of enzymatic tests as markers for early kidney damage allows for the classification of two main groups of patients: those requiring conservative treatment and those requiring urgent surgical intervention. This significantly reduces the frequency of inflammatory, purulent-septic complications and improves the treatment outcomes for patients with upper urinary tract obstruction in urolithiasis.

[Epidemiology and diagnosis of urinary lithiasis: a cross-sectional study in a Cameroonian based population]

Introduction

urinary stone is a multifactorial disease characterized by the presence of concretions in the urinary tract. The diagnosis of urinary lithiasis is based on clinical and imaging findings. The objective of this study was to determine the profile of patients suffering from urolithiasis in the city of Yaounde.

Methods

this was a descriptive observational cross-sectional study with retrospective data collection. Patients with an age > 15 years and patients diagnosed with lithiasis confirmed by medical imaging were included in our study. The variables studied were sociodemographic, clinical and paraclinical.

Results

a total of 120 patients were included in our study. The mean age was 40.46±12.62 years with extremes from 19 to 74 years. Male gender was predominant at 60.8% (n=73). Renal colic was the circumstance found in 67.5% (n=81). Physical examination was normal in 55.8% (n=67). Insufficient hydration was found in 45% (n=61) of cases. Abdominal scanner was the most performed examination in our study in 50.7% (n=61). The median stone density was 731 Hounsfield units [346; 1183.5]. The stones were predominantly located in the upper tract. The left renal topography was predominant in 35% (n=42) of cases. Urine culture revealed Escherichia Coli at 60% (n=15). Blood calcium, phosphorus and uricemia were requested in 15.8% (n=19), 0.8% (n=1) and 12.5% (n=15) of cases, respectively. The results were normal. In the absence of a laboratory specialized in biochemical analysis of calculi, a minority of patients (n=3) benefited from spectrophotometry.

Conclusion

urinary lithiasis is a disease of men in their forties. Renal colic is the main revealing sign. The diagnosis is revealed by the abdominal scanner in half of the cases. Metabolic assessment and constitutional analysis of the calculus are still very rarely requested.

Predictors for Distinguishing Renal Infarction From Urolithiasis in the Emergency Department: A Randomly Matched Retrospective Case-Control Study

BACKGROUND

Emergency department (ED) clinicians may misdiagnose renal infarction (RI) as urolithiasis because RI is a rare disease with presenting symptoms similar to the symptoms of urolithiasis. However, earlier diagnosis of RI can improve patient prognosis.

OBJECTIVES

We investigated potential predictors for distinguishing RI from urolithiasis based on clinical findings and laboratory results.

METHODS

This randomly matched retrospective case-control study included patients who had been diagnosed with acute RI or acute urolithiasis between January 2016 and March 2020. Patients were excluded if they were aged under 18 years, had a history of trauma, or had incomplete medical records. Using a matching ratio of 1:4, RI patients were randomly matched to urolithiasis patients. Multivariable logistic regression was performed to identify factors that could distinguish RI from urolithiasis.

RESULTS

In total, 48 patients were included in the RI group and 192 patients were included in the urolithiasis group. Multivariable logistic regression showed that age ≥ 65 years (odds ratio [OR] 6.155; p = 0.022), atrial fibrillation (OR 18.472; p = 0.045), current smoking (OR 17.070; p = 0.001), costovertebral angle tenderness (OR 0.179; p = 0.037), aspartate aminotransferase level ≥ 27.5 U/L (OR 6.932; p = 0.009), sodium level ≥ 138.5 mEq/L (OR 0.079; p = 0.004), and hematuria (OR 0.042; p = 0.001) were significant predictors that could distinguish RI from urolithiasis. Based on these results, a nomogram was constructed.

CONCLUSION

Age ≥ 65 years, atrial fibrillation, current smoking, absence of costovertebral angle tenderness, aspartate aminotransferase level ≥ 27.5 U/L, sodium level < 138.5 mEq/L, and absence of hematuria were predictors that can distinguish between RI and urolithiasis.

[Urolithiasis-Therapy and recurrence prevention taking into account gender-specific aspects]

The prevalence of urolithiasis is steadily increasing worldwide in both genders. Diet and lifestyle, such as the rising prevalence of obesity and other metabolic syndrome traits, are considered key factors in this trend. Gender differences as a result of interventional therapy for urolithiasis have not been observed. However, iatrogenic injury to the male urethra is considered the most common reason for urethral strictures after endourologic (stone) therapy. In contrast, sepsis, as the major cause of urinary stone-related mortality, is more frequently reported in women after ureterorenoscopy and percutaneous nephrolithotomy. There are also differences in the frequency of various types of stones between men and women. Calcium oxalate and uric acid stones are more commonly observed in men, while carbonate apatite and struvite are diagnosed more often in women. Urinary stone analysis is therefore paramount for successful recurrence prevention. Diagnosis is based on the assignment of patients to the low-risk or high-risk group. The medical nutrition and pharmacological measures for the therapy of the respective type of stone are based on the risk factors in 24 h urine samples. A personalized approach that accounts for gender differences could further improve treatment, and recurrence prevention decisions for urinary stones.

Attitudes of urologists on metabolic evaluation for urolithiasis: outcomes of a global survey from 57 countries

Although stone disease is an important health problem with high incidence and recurrence rates, it is a preventable disease. Attitudes and practices of urologists regarding the prevention of recurrence continue to be a subject of debate. In this context, an online survey study was conducted involving 305 urologists from 57 different countries. The first 7 questions collected demographic data about the urologists and the remaining 23 questions were about the recurrence and metabolic evaluation, medical treatment, and follow-up of urinary stone disease. Most urologists (85.2%) thought that metabolic examination was important. Approximately one-third of the participants (34.1%) performed 24-hour urine analysis and stone analysis was ordered by 87.5% of the urologists. Metabolic analysis was performed for all patients by 14.7% of the participants. For pediatric patients this rate was 68.5%, and for adults with recurrence the rate was 81.6%. Reasons cited by the urologists for not performing metabolic analysis included not feeling confident doing so (18.3%), having limited facilities in their hospital (26.5%), having an excessive daily workload (31.8%), patient-related factors (27.5%), and referring patients to other departments for metabolic evaluation (20.9%). Although majority of the responding urologists do consider the metabolic analysis as vital important, they seemed not to be willing to perform these tests with the same degree of enthusiasm in their daily practice. Our results show that urologists need support in performing and interpreting 24-hour urine analysis, improving their knowledge levels, and communicating with patients. Urology residency training should focus more on the prevention of urinary stone recurrence in addition to the surgical training.

Retrospective analysis of risk factors, clinical features, and prognostic indicators for urolithiasis in guinea pigs: 158 cases (2009-2019)

OBJECTIVE

To investigate risk factors, clinical features, and prognostic indicators in guinea pigs with urolithiasis.

ANIMALS

158 guinea pigs with urolithiasis.

PROCEDURES

Medical records of an exotics animal specialty service were searched, identifying guinea pigs with urolithiasis. Signalment, clinical data, and outcomes were recorded. Variables of interest were analyzed for statistical associations with outcome.

RESULTS

Overall, 54.4% (86/158) of animals survived to discharge. Median survival time was 177 days. Females (53.2%; 84/158) were more common than males (46.8%; 74/158). Males were presented younger (mean age, 3.64 years) than females (4.41 years). In 81 of 154 (52.5%) cases, animals were presented with primary urinary concerns, while 73 (47.5%) presented for nonurinary primary concerns. Females more commonly presented with distal urinary tract urolithiasis (63/84; 75%) but fared better overall with a longer median survival time (1,149 days) than males (59 days). Surgical intervention was not a risk factor for nonsurvival; however, increased age (> 4.1 years), male sex, anorexia, weight loss, and lower rectal temperature (< 37.2 °C) on presentation were associated with nonsurvival. Reoccurrence was noted in 13.9% (22/158) of cases, at an average of 284 days.

CLINICAL RELEVANCE

Urolithiasis should always be considered a differential diagnosis for any unwell guinea pig. In particular, distal urinary tract urolithiasis should be considered in females. A poorer prognosis was associated with older, male guinea pigs, and those displaying anorexia, weight loss, and hypothermia. The need for surgical intervention should not confer a poorer outcome. Further studies are needed to determine specific risk factors and identify possible preventative measures.

Development and validation of a clinical diagnostic model for pregnant women with renal colic in the emergency department in China: a protocol for a retrospective cohort study

INTRODUCTION

Urolithiasis affects many people throughout their lives. Among the maternal population, although the morbidity of acute urolithiasis in pregnant women is unremarkable, it is the leading cause of hospitalisation during pregnancy. There is no effective clinical diagnostic tool to help doctors diagnose diseases. Our primary aim was to develop and validate a clinical prediction model based on statistical methods to predict the probability of having disease in pregnant women who visited the emergency department because of urolithiasis-induced colic.

METHODS AND ANALYSIS

We will use multivariate logistic regression analysis to build a multivariate regression linear model. A receiver operating characteristic curve plot and calibration plot will be used to measure the discrimination value and calibration value of the model, respectively. We will also use least absolute shrinkage and selection operator regression analysis combined with logistic regression analysis to select predictors and construct the multivariate regression model. The model will be simplified to an application that has been reported before, and users will only need to enter their clinical parameters so that risk probability is automatically derived.

ETHICS AND DISSEMINATION

The review and approval documents of the clinical research ethics committee have been received from the ethics committee of our hospital (The Third Affiliated Hospital of Wenzhou Medical University). We will disseminate research findings through presentations at scientific conferences and publication in peer-reviewed journals.

Small ruminant urinary obstruction: decision trees for treatment

Urolithiasis is the most common cause of urinary tract disease in small ruminants and has significant economic and production impacts worldwide. Urolithiasis is multifactorial in origin and generally begins with the formation of cystoliths followed by urethral obstruction. The condition is most common in males. Clinical signs are variable depending on the severity of the obstruction. Uroliths can be calcium, struvite, or silicate based; however, struvite and amorphous magnesium calcium phosphate are the most common urolith types observed in small ruminants. Although urethral process (vermiform appendage) amputation is widely considered the first line of treatment, reobstruction is common within the first 36 hours. Surgical interventions such as temporary tube cystostomy, perineal urethrostomy (PU), modified proximal perineal urethrostomy, vesico-preputial anastomosis (VPA), and urinary bladder marsupialization (BM) are reported to carry an improved prognosis for long-term survival. PU carries a lower proportion of long-term success (> 12-month survival time) when compared with VPA and BM. Stoma stricture and urine scald are the most commonly observed surgical complications. Currently, the literature provides minimal direction for clinician decision-making in managing these cases while accounting for patient history, client financial ability, composition of calculi, and potential treatment complications. Small ruminant urinary obstructions are challenging and complicated conditions to treat, due to their multifactorial etiology, ruminant urogenital anatomy, and the variety of imperfect treatment options available. The purpose of this article this article is to provide veterinary practitioners with decision trees to guide management and treatment of urolithiasis in small ruminants.

[The tale of two stones in an obstructed partial duplex kidney: case presentation]

Duplex renal systems is a common anomalies. Incidence rate of 0.8% in healthy adult population and 2-4% in patients investigated for urinary tract symptoms. Urolithiasis management for patients with anomalies is complex and require proper imaging and planning. We have a patient with a partial duplex collecting system presented with a right renal calculus in a non-functioning lower moiety and multiple distal ureteric calculi. Preoperative planning done and surgery performed with good outcome without any early and late complications.

Endothelial Dysfunction: An Intermediate Clinical Feature between Urolithiasis and Cardiovascular Diseases

An epidemiological relationship between urolithiasis and cardiovascular diseases has extensively been reported. Endothelial dysfunction is an early pathogenic event in cardiovascular diseases and has been associated with oxidative stress and low chronic inflammation in hypertension, coronary heart disease, stroke or the vascular complications of diabetes and obesity. The aim of this study is to summarize the current knowledge about the pathogenic mechanisms of urolithiasis in relation to the development of endothelial dysfunction and cardiovascular morbidities.

METHODS

A non-systematic review has been performed mixing the terms "urolithiasis", "kidney stone" or "nephrolithiasis" with "cardiovascular disease", "myocardial infarction", "stroke", or "endothelial dysfunction".

RESULTS

Patients with nephrolithiasis develop a higher incidence of cardiovascular disease with a relative risk estimated between 1.20 and 1.24 and also develop a higher vascular disease risk scores. Analyses of subgroups have rendered inconclusive results regarding gender or age. Endothelial dysfunction has also been strongly associated with urolithiasis in clinical studies, although no systemic serum markers of endothelial dysfunction, inflammation or oxidative stress could be clearly related. Analysis of urine composition of lithiasic patients also detected a higher expression of proteins related to cardiovascular disease. Experimental models of hyperoxaluria have also found elevation of serum endothelial dysfunction markers.

CONCLUSIONS

Endothelial dysfunction has been strongly associated with urolithiasis and based on the experimental evidence, should be considered as an intermediate and changeable feature between urolithiasis and cardiovascular diseases. Oxidative stress, a key pathogenic factor in the development of endothelial dysfunction has been also pointed out as an important factor of lithogenesis. Special attention must be paid to cardiovascular morbidities associated with urolithiasis in order to take advantage of pleiotropic effects of statins, angiotensin receptor blockers and allopurinol.

Usefulness and acceptability of a Smart pH meter and mobile medical App as a monitoring tool in patients with urolithiasis: short-term prospective study

ORIGINAL ARTICLE

Usefulness and Acceptability of a Smart pH Meter and Mobile Medical App as a Monitoring Tool in Patients with Urolithiasis: Short-term Prospective Study.

OBJECTIVE

An accurate strategy for regularly measuring urine pH is the use of portable electronic pH meters. This study evaluated the usefulness and acceptability of the smart Lit-Control® pH Meter connected with a companion mobile medical application (myLit-Control(R) App) used by patients with urolithiasis for home monitoring of urine pH. We also examined adherence and compliance rates, and users´ satisfaction levels. MATERIALS AND METHODS: This was a multicenter, prospective study conducted in 10 centers from Spain. Adult patients with a history of urolithiasis were recruited and instructed to carry out a pH measurement with the pH meter three times per day for two weeks. User tasks included turning on the device, registration and on boarding processes in the App, sync the device and the App, and data dumping. At the end of the trial, we evaluated the level of adherence and usage compliance. Participants' perceptions about the usefulness, acceptability, and satisfaction with the device/App were collected through the Computer System Usability Questionnaire (CSUQ) and subjective surveys. RESULTS: Participants were 27 men and 10 women. The mean age of participants was 48.7 (SD = 10.4) years, ranging from 25 to 66. The predominant type of stone was calcium oxalate. The mean pH of all readings was 5.83 (SD = 0.41). Seventy-three (73%) patients met the "good adherence" criterion (not being more than 2 days without recording any pH value). The compliance (actual vs. theoretical readings) was 87.6%. Participants rated the usability of the App 5.4 and above (on a 7-point scale) in all the items of CSUQ. Satisfaction was high, as indicated by the mean score of 6.0 in item 16. In the subjective questionnaire (0 to 3 scale), nearly all mean values were above 2. Patients scored their probability to recommend the App with an average of 8.2 on a 0 to 10 scale.

CONCLUSION

The new smart Lit-Control® pH Meter and the accompanying medical App were deemed useful and acceptable by urolithiasis patients as a portable tool for urine pH monitoring at home. The usage compliance rates were high and the satisfaction with the products was good.

How important urolithiasis is under 2 years of age?

Urolithiasis (UL) is a common health problem in the world and the observed incidence of this disease is increasing in the infantile period. The study included cases of UL diagnosed before the age of two who had a comprehensive analysis for possible etiologic variables and were followed for a minimum of 6 months. Of the 60 patients included in the study, 37 were male, and the male/female ratio was 1.6. The average age at diagnosis is 8.5 ± 4.5 months. Of the cases diagnosed 41 (68.3%) were before than 1 year of age. The average time for follow-up is 28.9 ± 22.6 months. There was a family history of stone disease in 41 (68.3%) cases. Twenty-four (40%) patients were treated for dehydration at least once before stone disease was identified. The number of patients presenting with symptoms is 43 (71.7%). Restlessness was noted as the main symptom. In 17 (28.3%) patients, stone disease was found incidentally. Metabolic causes (n: 19, 31.6%) were determined to be the most common underlying cause, followed by UTI-related causes (n: 12, 20%). During the follow-up, 57 (64%) of the stones spontaneously disappeared. The size of 16 (18%) stones reduced, while the size of eleven remained same (13%). Following their absence, nine (15%) of the stones reappeared. The essential strategy is to identify high-risk groups, to closely monitor them, and to take preventative interventions against modifiable conditions such as dehydration if possible.

[The methodology of remote monitoring of patients with urinary stone disease: development and primary approbation]

INTRODUCTION

Urolithiasis is a clinically and socially significant disease that requires long-term follow-up in order to prevent stone recurrence. Currently, telemedicine consultations in the "patient-doctor" format are actively used in urology, however, the methodology, technological base and assessment of the efficiency of remote monitoring of the patient's health status are virtually not developed.

AIM

To provide basics for the methodology of remote monitoring of patients with urolithiasis for detailed comprehensive examination and comprehensive metaphylaxis of recurrent stone formation.

MATERIALS AND METHODS

A comprehensive clinical examination was carried out on the basis of the Institute of Urology and Human Reproductive Health, the National Medical Research Center on Urology and the Institute of Digital Medicine of FGAOU VO I.M. Sechenov First Moscow State Medical University during the period from 1st February to 1st December 2020. A total of 30 patients with urolithiasis were included in the study. Remote monitoring of health status was carried out using a portable analyzer "ETTA AMP-01" on dipstick. Data transmission was performed through a mobile application, which is part of the "NetHealth" information system (www.nethealth.ru). The values and frequency of urine tests performed by the patient independently, as well as patient satisfaction and adherence to the monitoring technology were evaluated. Analytical, clinical, sociological and statistical research methods were used.

RESULTS

By systematizing published data and our own clinical experience, we have developed a model for remote monitoring of the health status of patients with urinary stone disease, which included a system of indications and contraindications, a program and an order of the monitoring, as well as a basic technological solution (medical devices and a hardware-software complex). In this study, median duration of remote monitoring was 168 days. According to the questionnaire, general positive assessment and desire to continue telemonitoring was seen in 100.0% of cases, while 86.7% of patients positively evaluated the technical accessibility and reliability of the system and 93.3% considered the quality and availability of medical care as high.

CONCLUSION

A methodology for remote monitoring of patients with urolithiasis has been developed with the aim of preventing recurrent stone formation. There was a high adherence of patients to remote monitoring with a tendency to decrease in values after 4 and 6 months. During these periods, it is necessary to carry out routine consultations by the physician who appointed remote monitoring in order to continue the follow-up program. There was a high satisfaction of patients with remote monitoring, and they pointed out the quality and availability of urological care owing to telemedicine technologies.

[Metabolic Stone assessment: Underused tool and how to implement it on daily practice.]

Nephrolithiasis is a highly prevalent disease presenting itself mostly at a working age, which leads to a great economic burden on health system. Kidney Stone disease should be viewed as a systemic disorder,associated with or predictive of hypertension, insulin resistance, chronic kidney disease and cardiovasculardamage. According to current guidelines and evidence,a full screening of risk factors for kidney stones and for cardiovascular damage should be recommended in all cases of kidney stone disease, yet it is rarely performed, and a real-world clinical practice is lacking. The aim of this narrative literature is to serve as guidance for a patient-tailored dietary suggestion after a clinical and biochemistry evaluation, with limited resources, and still offer a rational management of kidney stone patients. Meta-analysis, systematic review, experimental studies, case-control plus high-impact factor journals PubMed and EMBASE, on the topic were included. Search criteria included metabolic profile, metabolic work-up, kidney stone, urolithiasis between 2010 and 2020.

[DISCRIMINANT ANALYSIS AS A SUPPORTING METHOD OF DECISION-MAKING IN MEDICAL INVESTIGATIONS ON THE EXAMPLE OF THE ENZYME IMMUNOASSAY IN PATIENTS WITH UROLITHIASIS]

The purpose of this article is to study the possibilities of discriminant analysis as a statistical decision support tool in medical research, using the example of the problem of choosing a tactics for treating patients with urolithiasis. based on the results of enzyme-linked immunosorbent assay. Discriminant analysis was carried out on an array of clinical and laboratory data of 70 patients with urolithiasis, of which two groups were formed: Group I included 36 patients who underwent conservative therapy; Group II consisted of 34 patients who underwent surgery. In the discriminant model, 11 indicators of general clinical examination of blood and urine, biochemical methods of blood testing and indicators of enzyme immunoassay were selected. The analysis of the constructed discriminant model made it possible to combine indicators of different nature into a single picture and solve the following tasks: find a combination of inflammation predictors and general analysis indicators in order to distinguish a group of patients requiring surgery from a group of conservative treatment; select the most informative indicators. Discriminant analysis showed the statistical significance of using the threshold values for the level of β2-microglobulin and NGAL-lipocalin. According to the discriminant model, a change in the level of β2-microglobulin is associated with changes in ESR parameters and the gender of patients (Wilks' Lambda: 0.51, approx. F (4.65)=15.47, p <0.01), and lipocalin values - with indicators of ESR, interleukin and the patient's age (Wilks' Lambda: 0.5; F (4.65)=15.87; p <0.01). Also, according to the used model, in the early diagnosis of Urolithiasis, the level of β2-microglobulin is a more informative sign than the level of lipocalin. Thus, the combinations of parameters of general, biochemical blood analysis and indicators of enzyme-linked immunosorbent assay of urine, found using discriminant analysis, which characterize the work of the body's defense subsystems in an acute state of the urolithiasis, may be useful in making a doctor's decision on the choice of treatment tactics.

Development of an Innovative Method by Optimizing qPCR Technique for Isolating and Determining Oxalobacter Formigenes Microbial Load in the Stool of Patients with Urolithiasis

INTRODUCTION

Oxalobacter formigenes, as a gram-negative anaerobic bacterium, metabolizes oxalate in the intestine by the enzymes oxalyl-CoA decarboxylase (OXC) and formyl-CoA transferase (FRC). Therefore, not only the presence of the bacterium but also microbial load may affect intestinal absorption and urinary exertion. We evaluated the relationship between Oxalobacter formigenes load and the formation of calcium oxalate urolithiasis using quantitative molecular methods.

METHODS

By clinical manifestation and stone analysis, we selected the urine and stool specimens of 73 patients with calcium oxalate urolithiasis. First, the gene regions of the two genes FRC and OXC in Oxalobacter formigenes were selected utilizing bioinformatics and specific primers designed for these regions. Following DNA extraction from stool specimens by specific primers of each gene, PCR was carried out and positive samples were sequenced. Then, qPCR was applied to determine the effective load of Oxalobacter. Also, biochemical tests were performed to measure the excretion rate of oxalate in urine specimens.

RESULTS

In addition to oxalobacter identification by PCR, the load of bacteria was quantitatively assessed using qPCR by specific primers for both FRC and OXC gene regions. A significant negative relationship had found between the formation of calcium oxalate urolithiasis and the presence of Oxalobacter formigenes in patients with kidney stone disease. The mean excretion of oxalate and citrate in urolithiasis cases were 22.93 and 552.106 mg/24h, respectively.

CONCLUSION

The presence of Oxalobacter formigenes can highly inhibit the generation of calcium oxalate urolithiasis. Furthermore, molecular techniques are more effective than other methods such as culture for the isolation of this bacterium.

[Urinary pH relevance on urolithiasis management.]

OBJECTIVE

Urinary pH is a factor that influences in urinary lithogenesis. It can condition the heterogeneous nucleation of calcium oxalate and the crystallization or dissolution of other substances such as uricacid, cystine and phosphates. Its exact and precise measurement is a tool to guide the treatment and prevention. The most accurate way to measure the pH is to use a glass electrode and a pH-meter, but this device is used in hospital's environment and is not portable. Test strips are not adequate for proper measurement. Recently, a portable and electronic device for measuring urinary pH has shown greater precision and accuracy in the measurement of urinary pH, with good acceptance by patients.

METHOD

We carried out a bibliographic search inPUBMED and EMBASE using the terms "URINARY pH", "Lithiasis", "Uro-Lihitiasis", "Urinary Stone", "Urinary pH measurement", in order to compile articles, books, abstracts and the most relevant clinical guides in English and Spanish on this topic.

RESULTS

We select a total of 66 articles, 3 books, an abstract of a study unpublished presented at the American urology congress and the European Guidelines on urolithiasis on the effect of pH on the formation and prevention of urolithiasis. Four articles deal specifically with the effect of urinary pH on urolithiasis, 5 articles deal with a new portable electronic device for measuring urinary pH, 5 articles dealt with the measurement of urinary pH with test strips and 1 article dealt with the modification of urinary pH to reduce fouling of double J catheters, 2 articles deal about the urinary acidification with oral methionine. The selected abstract deals with the new portable device for measuring urinary pH in cystinuric patients. The 3 selected books have specific sections where the role of urinary pH in urolithiasis is discussed. Finally, in the European Urology Guidelines, the control of urinary pH is emphasized in the sections of prevention of urolithiasis formation, treatment of uric lithiasis, infectious/non-infectious phosphocalcic and cystine.

CONCLUSIONS

Urinary pH is a recognized factor in the scientific-urological community for the study, monitoring, treatment and prevention of lithiasic patients. Urinary pH measurement is a very useful tool, but test strips are not suitable for pH measurement and medical decision making. Currently, several studies have evaluated a new device to achieve the measurement of urinary pH effectively and easily by the patient, keeping urinary pH innon-lithogenic ranges with the association of medical and non-medical treatments, and good acceptability from the patients.

Comparison of current guidelines on medical management of stone disease

OBJECTIVE

The objective of this study isto present the content of existing Guidelines on medical management of urinary stone disease.

MATERIALS AND METHODS

A search for current Guidelines from national and international urological Associations was performed in Societe International d'Urologie and American Urological Association websites, along with a search in Pubmed/MEDLINE until 30/06/2020. Two authors performed an independent search and data extraction regarding medical management of acute renal colic, medical expulsive treatment, dietary modifications and pharmaceutical interventions for prevention of stone disease recurrence. Quality of Guidelines was assessed by the two reviewers using the AGREE II instrument.

RESULTS

Literature search revealed 82 Associations, while eight of them provide recommendations/Guidelines on medical management of stone disease. Non-steroidalanti-inflammatory drugs or paracetamol are the most common 1st line treatment proposed for acute pain management, with opiates following next. Use of a-blockers is also indicated by most Guidelines for facilitating expulsion of distal ureteral stones 5-10 mm, after shockwave or laser lithotripsy or for alleviating stent-related symptoms. Adequate fluid in take, normal dietary calcium consumption and sodium restriction with varying daily limits, are universal dietary modifications from urological Associations on prevention of stone disease. Thiazidesand alkaline citrates are proposed usually for calciumoxalate stone formers with differences in grading of the recommendations, while urinary alkalization with allopurinol or febuxostat as a second line treatment is acommon treatment algorithm for urate stones, but with differences in target urine pH. European and American Urological Association Guidelines, along with National Institute for Health and Care Excellence recommendations were the most highly rated based on AGREE II.

CONCLUSIONS

Despite methodological heterogeneity and subjective rating of recommendations, an acceptable degree of consensus was noted on Guidelines regarding medical management of stone disease.

Guideline-adherence in the treatment of symptomatic urolithiasis in children and adolescents in southwestern Germany

BACKGROUND

Approximately 1% of urolithiasis cases in Germany affect children. Interdisciplinary groups have agreed on national and international guidelines for children to recommend appropriate treatment pathways. The aim of this retrospective and preliminary study is to analyze whether adherence to current guidelines for pediatric stone disease in southwestern Germany is feasible.

METHODS

During 2014 to 2017 24 children and adolescents (nine female, 15 male, median age 9.7 years), were treated for symptomatic urolithiasis in our institutions. We retrospectively collected clinical and operative courses. Clinical pathways were compared to previous guideline recommendations of the EAU 2014 and the German S2k guideline 2015.

RESULTS

17 of the 24 patients were treated according to guideline recommendations (71%). Non-adherency was based on parental decisions in two and technical/medical considerations in five cases. In 11 children (45.8%) secondary or adjunctive treatments were necessary, in three of the seven non-adherently treated (43%) and in eight of the 17 adherently treated children (47%).

CONCLUSION

Our daily treatment approach seems to comply well with current pediatric stone guidelines. Nevertheless, guideline-non-adherent decision making emphasizes their strength and limitations, as specific clinical situations in children may require an individual treatment plan, as non-predictable conditions may occur.

[Strategies and recommendations for urolithiasis treatment and follow-up in COVID-19 pandemia.]

The health crisis caused by COVID-19 pandemic has led to a restructuring of urological activity in order not to delay priority situations. An important part to prioritize within Urologyis Urolithiasis. The objective of this article is to establish strategies and recommendations for the treatment and follow-up in COVID-19 pandemic in phases I, II and III, based on available scientific evidence and the consensus of a group of experts in these pathologies. MATERIAL AND METHODS: The document is based on the evidence available in the literature so far on SARSCoV-2 and the experience of the authors in the management of COVID-19 in their institutions. A narrative review of the literature was conducted, and a modified nominal group technique was used due to the extraordinary restrictions of assembly and mobility during the pandemic. RESULTS: Recommendations are made regarding the epidemiological evaluation of patients before surgery ,the management of positive patients, the epidemiological measures for healthcare personnel, the management of renal colic, the type of anesthesia, endourological surgery, shockwave lithotripsy, hospitalization, clinicalt ests, out-patient service and priorities on the surgical waiting list. CONCLUSION: Treatment of Urolithiasis in COVID-19 pandemic calls for prioritization of patients, maximum efficiency in treatments, adequate protection of healthcare personnel, and the implementation of telemedicine as a measure to reduce patient attendance to the hospital.

Effects on renal outcome of concomitant acute pyelonephritis, acute kidney injury and obstruction duration in obstructive uropathy by urolithiasis: a retrospective cohort study

OBJECTIVE

Obstruction release from urolithiasis can be delayed with a lack of suggested time for preventing the deterioration of renal function. The objective of this study was to investigate the effect of obstruction duration, concomitant acute kidney injury (AKI) or acute pyelonephritis (APN) during the obstruction on the prognosis of renal function.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

1607 patients from a urolithiasis-related obstructive uropathy cohort, between January 2005 and December 2015.

OUTCOME MEASURES

Estimated glomerular filtration rate (eGFR) decrease ≥30% and/or end-stage renal disease (ESRD), and eGFR decrease ≥50% and/or ESRD, according to obstruction duration, AKI and APN accompanied by obstructive uropathy.

RESULTS

When the prognosis was divided by obstruction duration quartile, the longer the obstruction duration the higher the probability of eGFR reduction >50% (p=0.02). In patients with concomitant APN or severe AKI during hospitalisation with obstructive uropathy, an eGFR decrease of >30% and >50% occurred more frequently, compared with others (p<0.001). When we adjusted for sex, age, hypertension, diabetes mellitus, APN, AKI grades and obstruction release >7 days for multivariate analysis, we found that concomitant APN (HR 3.495, 95% CI 1.942 to 6.289, p<0.001), concomitant AKI (HR 3.284, 95% CI 1.354 to 7.965, p=0.009 for AKI stage II; HR 6.425, 95% CI 2.599 to 15.881, p<0.001 for AKI stage III) and an obstruction duration >7 days (HR 1.854, 95% CI 1.095 to 3.140, p=0.001) were independently associated with an eGFR decrease >50%. Tree analysis also showed that AKI grade 3, APN and an obstruction duration >7 days were the most important factors affecting renal outcome.

CONCLUSIONS

In patients with urolithiasis-related obstructive uropathy, concomitant APN was strongly associated with deterioration of renal function after obstruction release. The elapsed time to release the obstruction also affected renal function.

Urinary 2,8-dihydroxyadenine excretion in patients with adenine phosphoribosyltransferase deficiency, carriers and healthy control subjects

BACKGROUND

Adenine phosphoribosyltransferase (APRT) deficiency is a rare autosomal recessive disorder of adenine metabolism that results in excessive urinary excretion of the poorly soluble 2,8-dihydroxyadenine (DHA), leading to kidney stones and chronic kidney disease. The purpose of this study was to assess urinary DHA excretion in patients with APRT deficiency, heterozygotes and healthy controls, using a recently developed ultra-performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS) assay.

METHODS

Patients enrolled in the APRT Deficiency Registry and Biobank of the Rare Kidney Stone Consortium (http://www.rarekidneystones.org/) who had provided 24-h and first-morning void urine samples for DHA measurement were eligible for the study. Heterozygotes and healthy individuals served as controls. Wilcoxon-Mann-Whitney test was used to compare 24-h urinary DHA excretion between groups. Associations were examined using Spearman's correlation coefficient (r_s).

RESULTS

The median (range) 24-h urinary DHA excretion was 138 (64-292) mg/24 h and the DHA-to-creatinine (DHA/Cr) ratio in the first-morning void samples was 13 (4-37) mg/mmol in APRT deficiency patients who were not receiving xanthine oxidoreductase inhibitor therapy. The 24-h DHA excretion was highly correlated with the DHA/Cr ratio in first-morning void urine samples (r_s = 0.84, p < .001). DHA was detected in all urine samples from untreated patients but not in any specimens from heterozygotes and healthy controls.

CONCLUSIONS

High urinary DHA excretion was observed in patients with APRT deficiency, while urine DHA was undetectable in heterozygotes and healthy controls. Our results suggest that the UPLC-MS/MS assay can be used for diagnosis of APRT deficiency.

[Distal Renal Tubular Acidosis: Clinical Variability in the Same Family]

Primary distal renal tubular acidosis is a genetic disorder characterized by the inability in acidification of urine. Symptoms are usually non-specific and highly variable. We described six cases in a family with four generations affected. The first case was diagnosed in a 3-year-old child presenting with hematuria and urolithiasis. Later, his sister, sons and two nephews were studied. Although asymptomatic, they all had nephrocalcinosis and hyperchloremic metabolic acidosis with normal anionic gap, except one case with normal arterial blood gas test but with nephrocalcinosis and inability of urinary acidification. At follow-up, they all maintained nephrocalcinosis, the index case had acute renal damage and developed hypertension, but none developed chronic renal disease. The diagnosis of autosomal dominant distal renal tubular acidosis is generally made later and patients tend to present with milder disease. But the condition may manifest early and have a variable phenotypic severity spectrum. Carrying out screening through assessment of family history enables an earlier diagnosis while also allowing treatment to start sooner.

Association of Adherence to The Mediterranean Diet with Urinary Factors Favoring Renal Lithiasis: Cross-Sectional Study of Overweight Individuals with Metabolic Syndrome

Our purpose was to study the relationship of adherence to the Mediterranean diet (MedDiet) with urinary factors that favor the formation of renal calcium and uric acid stones in overweight and obese participants who had metabolic syndrome. This cross-sectional study examined 267 participants. A well-known MedDiet score (range 0–9) was calculated for each patient, and patients were then categorized has having low (≤3), medium (4–5), or high (≥6) adherence to the MedDiet. Baseline characteristics and urinary parameters were also analyzed. High calcium salt urinary crystallization risk (CaUCR) and high uric acid urinary crystallization risk (UrUCR) were calculated from urinary parameters using pre-defined criteria. More than half of patients with MedDiet scores ≤3 had high UrUCR (55.4%) and high CaUCR (53.8%). In contrast, fewer patients with high adherence (≥6) to the MedDiet had high UrUCR (41.2%) and high CaUCR (29.4%). Relative to those with low adherence, individuals with high adherence had a prevalence ratio (PR) of 0.77 for a high UrUCR (95% CI: 0.46–1.12; p for trend: 0.069) and a PR of 0.51 for a high CaUCR (95% CI: 0.26–0.87; p for trend: 0.012) after adjusting for age, sex, body mass index, type 2 diabetes, and total energy intake. Our findings indicate that greater adherence to the MedDiet was associated with a reduced CaUCR and a reduced UrUCR. This suggests that adequate dietary management using the MedDiet patterns may prevent or reduce the incidence and recurrence of calcium salt and uric acid renal stones.

Management of urolithiasis in living kidney donors

BACKGROUND

Kidney donors with asymptomatic stones were  previously excluded from the kidney donation list because of a potential increased morbidity risk for both the recipient and the donor. Currently, recent studies tend to consider these risks as overestimated.

AIM

The aim of this study was to analyze our experience in the management of urolithiasis in potential donors.

METHODS

We conducted a retrospective analysis during the period (2008-2015). We included donors with urilithiasis or a family history of urolithiasis whom had urinary biochemical analysis of urolithiasis. We identified the exact location, size, and anatomy of the kidney bearing the stone were identified.

RESULTS

Among 252 potentially proposed living kidney donors (LKD) in two renal transplantation centers, we noted urinary lithiasis in 8 patients (3.17%). The mean age was 40,12±20 years old with a sex-ratio M/F at 0,3. We noted urinary lithiasis on radiographs in one case, on echographs in one case and on computerized tomography kidney angiography in 5 cases. All are not obese and without any medical history. In one case, there was no lithiasis detected but chemical urinary analysis was performed because of family renal stone history. We performed a 24-hours urine test, and examined PH, calcium and oxalate. The urine analysis, showed acidic pH and hypercalciuria in all cases associated to weddelite in 3 cases, hyperoxaluria in all cases. In one case, we noted vitamin D deficiency related hyperparathyroidism. Renal transplantation has been achieved in two cases. After a mean follow up of 11,25 months [range :27-84], no urological complications were noted.

CONCLUSION

Urinary lithiasis may occur in proposed living kidney donors and may not contraindicate this donation.

Occult urolithiasis in asymptomatic primary hyperparathyroidism

OBJECTIVE

Recent international guidelines suggest renal imaging to detect occult urolithiasis in all patients with asymptomatic primary hyperparathyroidism (PHPT), but data regarding their prevalence and associated risk factors are limited. We evaluated the prevalence and risk factors for occult urolithiasis.

METHODS

Cross-sectional analysis of 96 asymptomatic PHPT patients from a university hospital in the United States with and without occult nephrolithiasis.

RESULTS

Occult urolithiasis was identified in 21% of patients. Stone formers had 47% higher 24-hour urinary calcium excretion (p = 0.002). Although available in only a subset of patients (n = 28), activated vitamin D [1,25(OH)₂D] was 29% higher (p = 0.02) in stone formers. There was no difference in demographics, BMI, calcium or vitamin D intake, other biochemistries, renal function, BMD, or fractures. Receiver operating characteristic curves indicated that urinary calcium excretion and 1,25(OH)₂D had an area under the curve of 0.724 (p = 0.003) and 0.750 (p = 0.04), respectively. A urinary calcium threshold of >211mg/day provided a sensitivity of 84.2% and a specificity of 55.3% while a 1,25(OH)₂D threshold of >91pg/mL provided a sensitivity and specificity of 62.5% and 90.0% respectively for the presence of stones.

CONCLUSION

Occult urolithiasis is present in about one-fifth of patients with asymptomatic PHPT and is associated with higher urinary calcium and 1,25(OH)₂D. Given that most patients will not have occult urolithiasis, targeted imaging in those most likely to have occult stones rather than screening all asymptomatic PHPT patients may be useful. The higher sensitivity of urinary calcium versus 1,25(OH)₂D suggests screening those with higher urinary calcium may be an appropriate approach.

[Nephrotuberculosis and urolithiasis]

INTRODUCTION

Urolithiasis and nephrotuberculosis, due to the similarity of the radiographic patterns, share the same differential diagnosis list. The study aimed to analyze the incidence of co-occurrence of nephrotuberculosis and urolithiasis and to determine the impact of urolithiasis on the clinical course of renal tuberculosis.

MATERIAL AND METHODS

This open cohort retrospective study comprised 843 patients with renal tuberculosis and 245 patients with urolithiasis. 1088 medical records were analyzed to identify cases with co-occurrence of these two diseases and determine the clinical presentation of renal tuberculosis, urolithiasis, and the comorbid state. Also, patients with pulmonary tuberculosis (44), urogenital tuberculosis (17), and chronic nonspecific pyelonephritis (12) were tested for serum concentration of total calcium and phosphorus.

RESULTS

Of 843 patients with renal tuberculosis, 39 (4.6%), had concomitant nephrolithiasis. The combination of urolithiasis with nephrotuberculosis manifested by more severe symptoms; these patients had a more than two-fold risk of tuberculosis recurrence. Except for the incidence of renal colic and dysuria, the clinical manifestations of urolithiasis and nephrotuberculosis did not differ statistically significantly. Prolonged infectious and inflammatory process in the kidneys resulted in an increase in the excretion of oxalates, which was more pronounced in patients with nonspecific pyelonephritis (p<0.05). A three-month course of antituberculosis chemotherapy resulted in a 36.2% increase in the excretion of oxalates in patients with urotuberculosis (p<0.05). Excretion of uric acid also significantly increased after a three-month intake of antituberculosis drugs.

CONCLUSION

In our study, the incidence of concomitant urolithiasis and urogenital tuberculosis was low (4.6%), but comorbidity significantly complicated the clinical course of the disease and worsened the prognosis of nephrotuberculosis. Antituberculosis polychemotherapy increases the risk for formation of urinary stones. Prevention of urolithiasis in patients with urogenital tuberculosis warrants further investigation.

Urinary Stone Disease: Diagnosis, Medical Therapy, and Surgical Management

Clinical suspicion of urolithiasis should be evaluated with low-dose computed tomography as the first-line imaging modality for nonpregnant, adult patients. A period of observation may be appropriate for ureteral stones less than 10 mm, and medical expulsive therapy may be beneficial for facilitating passage of distal ureteral stones. Regardless of stone type, patients should adhere to a low-sodium diet and attempt to achieve a urine volume of more than 2.5 L daily. Individuals with calcium stones should maintain a normal calcium diet, and if stones persist, citrate therapy or thiazide diuretics in the setting of hypercalciuria may be indicated.

Struvite urolithiasis with eosinophilic polypoid cystitis in a shih tzu dog

A 7-year-old female spayed shih tzu dog was presented with hematuria of 4 weeks' duration. Radiographs revealed 1 cystic calculus. A polypoid mass was found incidentally during cystotomy and was removed by partial cystectomy. Histopathology revealed eosinophilic polypoid cystitis and urolith analysis reported struvite. A urinary tract infection was treated.