Pathogenesis of bladder calculi in the presence of urinary stasis

A comparative study of histotripsy parameters for the treatment of fibrotic ex-vivo human benign prostatic hyperplasia tissue

Histotripsy is a noninvasive focused ultrasound therapy that mechanically fractionates tissue to create well-defined lesions. In a previous clinical pilot trial to treat benign prostatic hyperplasia (BPH), histotripsy did not result in consistent objective improvements in symptoms, potentially because of the fibrotic and mechanically tough nature of this tissue. In this study, we aimed to identify the dosage required to homogenize BPH tissue by different histotripsy modalities, including boiling histotripsy (BH) and cavitation histotripsy (CH). A method for histotripsy lesion quantification via entropy (HLQE) analysis was developed and utilized to quantify lesion area of the respective treatments. These data were correlated to changes in mechanical stiffness measured by ultrasound shear-wave elastography before and after treatment with each parameter set and dose. Time points corresponding to histologically observed complete lesions were qualitatively evaluated and quantitatively measured. For the BH treatment, complete lesions occurred with >  = 30 s treatment time, with a corresponding maximum reduction in stiffness of -90.9 ± 7.2(s.d.)%. High pulse repetition frequency (PRF) CH achieved a similar reduction to that of BH at 288 s (-91.6 ± 6.0(s.d.)%), and low-PRF CH achieved a (-82.1 ± 5.1(s.d.)%) reduction in stiffness at dose >  = 144 s. Receiver operating characteristic curve analysis showed that a >  ~ 75% reduction in stiffness positively correlated with complete lesions observed histologically, and can provide an alternative metric to track treatment progression.

A Comparative Study of Histotripsy Parameters for the Treatment of Fibrotic ex-vivo Human Benign Prostatic Hyperplasia Tissue

Histotripsy is a noninvasive focused ultrasound therapy that mechanically fractionates tissue to create well-defined lesions. In a previous clinical pilot trial to treat benign prostatic hyperplasia (BPH), histotripsy did not result in consistent objective improvements in symptoms, potentially because of the fibrotic and mechanically tough nature of this tissue. In this study, we aimed to identify the dosage required to homogenize BPH tissue by different histotripsy modalities, including boiling histotripsy (BH) and cavitation histotripsy (CH). A method for histotripsy lesion quantification via entropy (HLQE) analysis was developed and utilized to quantify lesion area of the respective treatments. These data were correlated to changes in mechanical stiffness measured by ultrasound shear-wave elastography before and after treatment with each parameter set and dose. Time points corresponding to histologically observed complete lesions were qualitatively evaluated and quantitatively measured. For the BH treatment, complete lesions occurred with >=30s treatment time, with a corresponding maximum reduction in stiffness of -90.9±7.2(s.d.)%. High pulse repetition frequency (PRF) CH achieved a similar reduction to that of BH at 288s (-91.6±6.0(s.d.)%), and low-PRF CH achieved a (-82.1±5.1(s.d.)%) reduction in stiffness at dose >=144s. Receiver operating characteristic curve analysis showed that a >~75% reduction in stiffness positively correlated with complete lesions observed histologically, and can provide an alternative metric to track treatment progression.

A Forgotten Double-J Ureteric Stent as the Core of a Bladder Stone: A Case Report and Literature Review

BACKGROUND Double-J (D-J) ureteric stents are widely applied in urological operations as they play a vital role in maintaining postoperative functionality of the patient's urinary system and thereby accelerating recovery. D-J stent encrustation may occur due to prolonged retention and lead to secondary complications. We report the case of a forgotten D-J stent that gradually formed into a bladder stone. CASE REPORT A 54-year-old man was referred to the Urology Department due to intermittent hematuria, left flank pain, and lower urinary tract symptoms that persisted for 2 weeks. His history was significant for undergoing left ureterolithotripsy followed by the implantation of an ipsilateral D-J stents 2 years ago in a local hospital. The patient did not follow-up regularly or actively seek medical attention for his urinary tract symptoms. Computed tomographic urography revealed a hyperdense tubular object protruding from the left distal ureter to the bladder. The patient underwent cystolithotripsy, left ureteric stent removal, and left ureteroscopy to clear away the bladder stone and its D-J stent core. CONCLUSIONS Formation of bladder stones secondary to prolonged indwelling D-J stent and its encrustation is not uncommon in developing countries where the level of public education is low. Prompt D-J stent removal can prevent complications associated with its retention and avoid unnecessary secondary procedures. Endoscopic urologic procedures are safe and feasible management options, and doctor-to-patient communication is vital for a better prognosis.

Risk factors of bladder stones in neurogenic lower urinary tract dysfunction: A real-world study

Objective

The objective of this study is to investigate the incidence and risk factors for stone formation and recurrence in patients with neurogenic lower urinary tract dysfunction (NLUTD) in a real-world cohort.

Materials and methods

A retrospective cohort study was conducted on all patients with NLUTD who underwent bladder stone treatment between 2010 and 2022. Univariate and multivariate Cox models were used to identify the potential risk factors for stone recurrence.

Results

Among 114 patients included in the study, 30% experienced stone recurrence. The most common stone components were carbonate apatite phosphate and magnesium ammonium phosphate. The overall recurrence rate was 14 cases per 100 patient years. Neurogenic detrusor overactivity had the highest recurrence rate. Risk factors for stone recurrence in the multivariate analysis were intermittent and suprapubic catheterization, and recurrent urinary tract infection (rUTI).

Conclusions

Patients experienced multiple bladder stone recurrences. Close monitoring of bladder pressure and UTI with restrictive catheter application may reduce the risk of stone recurrence.

Bicentric retrospective study comparing the postoperative outcomes of patients treated surgically for bladder stones with or without concomitant surgery for BPH

PURPOSE

To compare the postoperative outcomes of male patients who underwent bladder stone (BS) removal, with or without concomitant benign prostatic hyperplasia (BPH) surgery.

PATIENTS AND METHODS

All men aged > 50 years who underwent BS removal at two French university hospitals between 2009 and 2018 were retrospectively reviewed. Four binary outcome criteria were identified during the follow-up: early postoperative complications, stone recurrence, subsequent surgery for BS or BPH, and late surgical complications. A composite score ranging from 0 to 4 was calculated by combining the four criteria.

RESULTS

A median follow-up period of 42 months was observed in 179 patients. Of these, 107 patients were in the "concomitant surgical treatment" (CST) group and 72 in the bladder "stone removal alone" (SRA) group. The CST group presented higher baseline post-void residual volume (105 vs. 30 ml, p = 0.005). Patients who underwent CST had a significantly lower rate of BS recurrence (12% vs. 39%; p = 0,001) and underwent fewer subsequent surgeries (14% vs. 44%; p < 0.001). There was no significant difference in the early (51% vs. 35%, p = 0,168) and late (26% vs. 17%, p = 0,229) complications rates between the two groups. A better composite score was observed in the CST than in the SRA, but the difference was not significant (3.07 vs. 2.72, p = 0.078).

CONCLUSION

As CST increases morbidity and decreases the risk of reoperation, each situation should be considered, taking into account patient choice and comorbidities.

Giant bladder calculi due to four years neglected cystostomy

Giant bladder calculi are rare and long-term usage of cystostomy could cause stone formation. Due to the lack of evidence on giant bladder calculi and the long-term usage of cystostomy can cause bladder calculi formation, we provide a case study of a man with a neglected cystostomy with giant bladder calculi for 4 years. A fixed mass was discovered in the suprapubic region. Ultrasound examination revealed 4.1 × 5.5 cm bladder calculi and contracted left kidney. Bipolar voiding cystourethrography portrayed stricture in pars pendular and membranacea, uneven bladder wall, and 4.5 × 4.5 cm bladder calculi. The stone was extracted, and the bladder filling test revealed a small bladder capacity. Since the patient refused urethral reconstruction and bladder augmentation, he was discharged with another cystostomy catheter. Six-month follow-up revealed no forming stones. Neglected cystostomy catheter can cause giant bladder calculi. Prompt diagnosis and treatment should be made to manage this condition to reduce the likelihood of bladder cancer.

Vesical Calculi and Female Pelvic Organ Prolapse: A Case Report and Literature Review

This study presents a case report and reviews the literature on the simultaneous occurrence of advanced uterovaginal prolapse and urolithiasis, aiming to provide a comprehensive analysis of the reported cases. A thorough search was conducted in PubMed and Google Scholar; the search strategy included specific keywords and terms related to both conditions aiming to identify relevant case reports describing the association between advanced uterovaginal prolapse and urolithiasis; a total of 22 case reports were found in English literature. We present a case report of a 56-year-old woman, para 4, presenting with complaints of vaginal bulge and urinary symptoms. Upon examination, a complete procidentia with superficial ulceration was observed. During the reduction of the uterus, multiple small stones were noted coming through the urethral meatus. The patient underwent a vaginal hysterectomy, and the bladder stone was successfully extracted through vaginal cystotomy without complications. Our case report highlights the association between vesical calculi and female high-grade pelvic organ prolapse. Managing bladder stones in the context of pelvic organ prolapse can be challenging and vary significantly, reflecting the individual patient characteristics and surgeon preferences. The lack of standardized guidelines for managing bladder stones in the presence of pelvic organ prolapse highlights the need for further research.

Rectal prolapse in a 30-year-old bladder stone male patient: A case report

BACKGROUND

Rectal prolapse occurs most commonly in children and middle-aged and elderly women and is relatively rare in young men and is occasionally caused by bladder stones. Severe rectal prolapse, bilateral hydronephrosis, and renal insufficiency caused by bladder stones are rare in a 30-year-old man.

CASE SUMMARY

We report the case of a 30-year-old male patient with cerebral palsy who presented with a large bladder stone that resulted in severe rectal prolapse, bilateral hydronephrosis, and renal insufficiency. Following a definitive diagnosis, the bladder stone was successfully removed, and his kidney function returned to normal. We assessed the patient’s nutritional status and stone composition and concluded that the main cause was malnutrition.

CONCLUSION

Rectal prolapse is a rare clinical manifestation of bladder stones, particularly in young adults. Cerebral palsy patients are a vulnerable group in society because of their intellectual disabilities and communicative impairments. Accordingly, besides taking care of their daily diet, abnormal signs in their bodies should receive the doctors’ attention in a timely manner.

Do men with bladder stones benefit from treatment of benign prostatic obstruction?

OBJECTIVE

To identify whether men aged ≥40 years with bladder stones (BS) benefit from treatment of benign prostatic obstruction (BPO).

PATIENTS AND METHODS

A regional, retrospective study of patients undergoing BS surgery between January 2011 and December 2018 was performed using a prospectively collected database. The primary outcome was BS recurrence after successful removal. Kruskal-Wallis and chi-squared statistical tests were used.

RESULTS

A total of 174 patients underwent BS removal and 71 (40.8%) were excluded due to BS formation secondary to causes other than BPO. Hence, 103 men aged ≥40 years had BS successfully removed, of which 40% had a history of upper tract urolithiasis. These men were divided into three groups: those undergoing contemporaneous medical, surgical, or no BPO treatment. Age, diabetes, previous urolithiasis and previous BPO surgery were well matched between the BPO treatment groups. In all, 18 of these men (17%) had BS recurrence after 46 months follow-up. Recurrences were significantly lower following BPO surgery; one of 34 (3%) men versus five of 28 (18%) with no BPO treatment (P = 0.048) and 12 of 41 (29%) with medical BPO treatment (P = 0.003). Recurrences after medical and no BPO treatment were similar (P = 0.280). In all, 34 men (33%) had BPO complications that were similar between groups (P = 0.378).

CONCLUSION

This is the largest reported cohort of men, with the longest follow-up after BS removal. Most men aged ≥40 years with BS benefit from BPO surgery. However, the study findings also support a multifactorial aetiology for BS, which questions the dogma that BS are an 'absolute indication' for BPO surgery, as is stated in the Non-neurogenic Male Lower Urinary Tract Symptoms European Association of Urology Guideline. Assessment and management of all causative factors is likely to enable selection of which men will benefit from BPO surgery and to reduce BS recurrence rates.

Prevalence and Predictors of Radiographically Apparent Upper Urinary Tract Urolithiasis in Eight Dog Breeds Predisposed to Calcium Oxalate Urolithiasis and Mixed Breed Dogs

Data on upper urinary tract (UUT) uroliths in dogs are important to understanding their etiology. The aim of this retrospective case-control study was to determine the prevalence and identify predictors of radiographically apparent UUT uroliths in dog breeds at increased risk for calcium oxalate uroliths (CaOx risk breeds) and mixed breed dogs. Radiologist reports of three-view abdominal radiographs were reviewed from 251 purebred dogs of 8 CaOx risk breeds and 68 mixed breed dogs. UUT uroliths were more common in CaOx risk breeds than mixed breed dogs (23% versus 6%, respectively; OR = 4.8, 95% confidence interval [CI] 1.7−18.9, p < 0.001). UUT uroliths were more common in dogs with lower urinary tract (LUT) uroliths (predominantly calcium-containing) than those without (41% versus 5%, respectively; OR = 13.6, 95% CI 6.3−33.1, p < 0.001), and LUT uroliths predicted the presence of UUT uroliths in the multivariable regression (OR = 6.5, 95% CI 2.8−16.7, p < 0.001). Increasing age (p < 0.001) and lower body weight (p = 0.0016) were also predictors of UUT urolith presence in the multivariable regression. The high prevalence of UUT uroliths in dogs with LUT uroliths supports a shared mechanism for their formation.

Case report. Geschokt door de wachttijd: ESWL bij blaasstenen

De behandeling van eerste keuze voor vesicale stenen is de transurethrale cystolithotripsie (TUCL). Door de COVID-19-pandemie kampen ziekenhuizen echter met lange wachttijden voor – onder meer – deze operaties. Daarnaast komen sommige patiënten niet in aanmerking voor een operatie door hun comorbiditeit. In de jaren negentig van de vorige eeuw was extracorporele shockwave lithotripsie (ESWL) een veel gebruikte, veilige behandelmethode voor blaasstenen. Toen TUCL effectiever bleek, is ESWL voor blaasstenen echter in de vergetelheid geraakt. ESWL is poliklinisch uit te voeren, waardoor wachttijden korter zijn dan die voor operatieve ingrepen. Gedurende de COVID-19-pandemie hebben we enkele patiënten met blaasstenen behandeld met ESWL. We concluderen dat ESWL een geschikt alternatief is voor de TUCL bij geselecteerde patiënten, maar dat voor een effectieve behandeling meerdere ESWL-procedures nodig zijn.

Assess the safety and effectiveness of a novel approach during transurethral pneumatic cystolithotripsy in large urinary bladder stone: quasi-clinical trial

To assess the safety and efficacy of using continuous irrigation-modified hysteroscopy during transurethral pneumatic cystolithotripsy for large bladder calculi. A prospective study was carried out from May 2016 until March 2020. All patients with solitary or multiple bladder stones > 2.5 cm were subjected to Transurethral pneumatic cystolithotripsy using a modified continuous irrigation hysteroscopy, the stone fragments were removed by Ellik Evacuator, the safety and effectiveness of the procedures were evaluated, stone-free rate (SFR), stone recurrence and stricture urethra disease during follow-up. 55 patients with a mean age of 57.36 (22-82) years were included, the male: female ratio was 4:1, single stone in 74.5% and the mean stone size was 52 mm. Lithotripsy time and an operative time were (20.39 ± 3.06 and 32.00 ± 3.57) minutes, respectively. Mean hospital stay was 10 ± 3.6 h. This endoscopic technique succeeded with a 100% SFR. During the 22 months of follow-up, no urethral stricture or stone recurrence was documented. The mean visual analog pain score (VAS) was 4.2 ± 2.1 and 1.4 ± 0.6, respectively, during and after the operation. The use of the modified hysteroscopy sheath during transurethral pneumatic cystolithotripsy is safe and effective for the management of large urinary bladder stones, an alternative to holmium laser in developing countries when laser equipment is unavailable. Comparable to other transurethral maneuvers, with a decrease in the risk of urethral stricture disease due to the small caliber of the device, as there is no urethral dilatation is required.

Synchronous transurethral cystolitholapaxy and TURP reveals better results than transurethral cystolitholapaxy plus medical therapy for BPH: a randomized prospective study on 100 patients with concomitant urinary bladder stone(s) and BPH

OBJECTIVE

This report presents the results of a randomized prospective study comparing synchronous transurethral cystolitholapaxy and transurethral resection of the prostate (TURP) with transurethral cystolitholapaxy plus medical treatment for benign prostatic hyperplasia (BPH) in patients with concomitant vesical stone(s) and BPH.

PATIENTS AND METHODS

The study included 100 patients with bladder stone(s) < 2.5 cm associated with BPH. Eligible patients were divided randomly into two groups: group I (n = 50 patients) underwent simultaneous transurethral cystolitholapaxy and TURP, and group II (n = 50 patients) underwent transurethral cystolitholapaxy and received postoperative tamsulosin plus finasteride.

RESULTS

The mean follow-up was 20.1 ± 5.3 months. No statistically significant differences were found between the 2 groups regarding the preoperative parameters (age, prostatic volume, bladder stone characteristics, prostate-specific antigen level, International Prostate Symptom Score, peak urinary flow rate, and post-void residual urine volume). Both groups experienced statistically significant postoperative improvement in IPSS, post-void residual (PVR) urine volume, and peak flow rate compared with the preoperative parameters (P < 0.001 for all parameters). However, patients in group 1 had a more pronounced improvement (P < 0.001 for all parameters). Thus, 15 patients in group 2 underwent TURP during follow-up. PVR urine and prostate volume predicted the failure of medical therapy and the need for TURP.

CONCLUSION

Synchronous transurethral cystolitholapaxy and TURP revealed better results than transurethral cytolitholapaxy plus medical therapy. Cystolitholapaxy without TURP should not be indicated especially in patients with significant PVR urine volumes and larger prostates.

Doppler-Assessed Ureteric Jet Frequency: A Valuable Predictor of Ureteric Obstruction

Objectives: To compare ureterovesical jet frequency in non-obstructed versus obstructed ureter secondary to ureteric stone using ultrasonography in patients presenting with ureteral stones.

Study design: Cross-sectional prospective study.

Place of study and duration: Urology Department, The Kidney Centre Post Graduate Training Institute from May 16 to November 15, 2019.

Methods: This study included 97 patients having presented in the emergency department with acute renal colic and were diagnosed as having ureteral stones on a non-contrast-enhanced computed tomography (NCCT). The ureteric jet frequency was measured by Doppler ultrasonography by our radiologist with the Hitachi Aloka F-37 ultrasound machine after they underwent CT. Patients were asked to drink 750-1000 ml of liquids 15-20 minutes before their ultrasonographic examination of both kidneys, ureters, and urinary bladder. The kidney size (length and width) and presence/absence of hydronephrosis were evaluated by grayscale ultrasound. Then, with the help of color Doppler ultrasonography, the frequency of the ureteric jet was recorded.

Results: The patient's mean age was 46.66 ± 3.21 years ranging from 37 to 56 years. There were 58 (59.8%) male and 39 (40.2%) female cases. The mean cumulative stone size was 9.77 ± 2.65 mm. According to stone location, 44 (45.4%) cases had upper ureteric, 24 (24.7%) cases had mid ureteric, and 29 (29.9%) cases had lower ureteric stone. The mean obstructive side jet frequency was 0.70/min ± 0.49, and the non-obstructive side jet frequency was 2.89/min ± 1.29 (P < 0.05).

Conclusions: The mean obstructive side jet frequency was 0.70 ± 0.49/min, which, if we compare to the non-obstructed normal ureter, is significantly less. Hence, color Doppler ultrasonography can be helpful to patients who were previously diagnosed with ureteral stones on NCCT to see if their stone has passed. This can be a very cost-effective modality especially in resource-poor countries where repeat CT can be very expensive. The results from this study can also be used in a specific population (i.e., pregnancy) where the use of imaging modalities that involve ionizing radiation is prohibited.

Primary aldosteronism is associated with risk of urinary bladder stones in a nationwide cohort study

We analyzed database from the Taiwan National Health Insurance to investigate whether primary aldosteronism (PA) increases the risk of bladder stones. This retrospective nationwide population-based cohort study during the period of 1998–2011 compared patients with and without PA extracted by propensity score matching. Cox proportional hazard models and competing death risk model were used to estimate the hazard ratios (HRs), sub-hazard ratios (SHRs) and corresponding 95% confidence intervals (CIs). There were 3442 patients with PA and 3442 patients without PA. The incidence rate of bladder stones was 5.36 and 3.76 per 1000 person-years for both groups, respectively. In adjusted Cox hazard proportional regression models, the HR of bladder stones was 1.68 (95% CI 1.20–2.34) for patients with PA compared to individuals without PA. Considering the competing risk of death, the SHR of bladder stones still indicates a higher risk for PA than a comparison cohort (SHR, 1.79; 95% CI 1.30–2.44). PA, age, sex, and fracture number were the variables significantly contributing to the formation of bladder stones. In conclusion, PA is significantly associated with risk of bladder stones.

Animal models of naturally occurring stone disease

The prevalence of urolithiasis in humans is increasing worldwide; however, non-surgical treatment and prevention options remain limited despite decades of investigation. Most existing laboratory animal models for urolithiasis rely on highly artificial methods of stone induction and, as a result, might not be fully applicable to the study of natural stone initiation and growth. Animal models that naturally and spontaneously form uroliths are an underused resource in the study of human stone disease and offer many potential opportunities for improving insight into stone pathogenesis. These models include domestic dogs and cats, as well as a variety of other captive and wild species, such as otters, dolphins and ferrets, that form calcium oxalate, struvite, uric acid, cystine and other stone types. Improved collaboration between urologists, basic scientists and veterinarians is warranted to further our understanding of how stones form and to consider possible new preventive and therapeutic treatment options.

Asymptomatic Uncountable Urinary Bladder Stones Removal: Play the Winner

Urinary bladder stones are a common condition in elderly males, and they are usually related to infravesical obstruction secondary to prostate enlargement. Endoscopic management of bladder stone is the gold standard treatment; yet, in some cases, return to conventional open surgery is necessary. In our article, we reported the case of a 73-year-old male patient with accidentally discovered multiple urinary bladder stones. Cystolithotomy was the treatment of choice which went uneventfully with a smooth postoperative course.

Extraction of giant bladder calcium oxalate stone: A case report

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Hyperoxaluria, hypercalciuria and a low urine calcium–oxalate ratio are involved in calcium oxalate monohydrate stone.

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For large-sized bladder stones, all the reports have recommended open cystolithotomy.

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Hyperoxaluria, and low urinary pH may promote the stone formation.

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Containment of animal protein and salt can reduce the relative risk of stone.

Introduction

Bladder stone is a rare and ancient disease. Nowadays new technologies have been developed in the effort to make less invasive stone treatment. Bladder calculi account for 5% of urinary calculi.

Presentation of case

A 52-year-old male patient with symptoms of lower abdominal pain, dysuria and pollakiuria was admitted. Urinalysis showed that pH5.0 and presence of calcium oxalate crystals and leukocyturia but erthrocyturia and nitrite were absent. Abdominal ultrasonogry revealed hydronephrosis, thickened bladder wall and large single stone. Plain radiography showed a large bladder stone measuring 12 × 10 cm.

Discussion

In our case 1 extremely large bladder calculus occupied most of the bladder and pressing on the orifices of the ureters, leading to the presence of hydronephrosis. For large-sized bladder stones, all the reports have recommended open cystolithotomy.

Conclusion

The combination of improved nutrition and modern antibiotic treatment has to be led to the frequency of bladder lithiasis. Calcium intake shouldn’t be restricted, whereas oxalate, sodium, and protein intakes have to be limited.

Pathological Mineralization: The Potential of Mineralomics

Pathological mineralization has been reported countless times in the literature and is a well-known phenomenon in the medical field for its connections to a wide range of diseases, including cancer, cardiovascular, and neurodegenerative diseases. The minerals involved in calcification, however, have not been directly studied as extensively as the organic components of each of the pathologies. These have been studied in isolation and, for most of them, physicochemical properties are hitherto not fully known. In a parallel development, materials science methods such as electron microscopy, spectroscopy, thermal analysis, and others have been used in biology mainly for the study of hard tissues and biomaterials and have only recently been incorporated in the study of other biological systems. This review connects a range of soft tissue diseases, including breast cancer, age-related macular degeneration, aortic valve stenosis, kidney stone diseases, and Fahr’s syndrome, all of which have been associated with mineralization processes. Furthermore, it describes how physicochemical material characterization methods have been used to provide new information on such pathologies. Here, we focus on diseases that are associated with calcium-composed minerals to discuss how understanding the properties of these minerals can provide new insights on their origins, considering that different conditions and biological features are required for each type of mineral to be formed. We show that mineralomics, or the study of the properties and roles of minerals, can provide information which will help to improve prevention methods against pathological mineral build-up, which in the cases of most of the diseases mentioned in this review, will ultimately lead to new prevention or treatment methods for the diseases. Importantly, this review aims to highlight that chemical composition alone cannot fully support conclusions drawn on the nature of these minerals.

Chronological changes in epidemiological characteristics of lower urinary tract urolithiasis in Japan

OBJECTIVES

To determine changes and trends in the annual incidence and epidemiological aspects of lower urinary tract stones in Japan.

METHODS

Data about patients who had been diagnosed by urologists in 2015 with first and recurrent lower urinary tract stones were collected from 301 hospitals approved by the Japanese Board of Urology. The estimated annual incidence according to sex, age and stone composition was compared with previous nationwide surveys between 1965 and 2005.

RESULTS

The incidence of lower urinary tract stones in Japan has steadily increased from 4.7 per 100 000 in 1965 to 12.0 per 100 000 in 2015. However, the age standardized annual incidence of lower urinary tract stones has remained relatively stable over the same period at 5.5 per 100 000 and 6.0 per 100 000 in 1965 and 2015, respectively. The increase in incidence was most evident among individuals aged ≥80 years. The incidence of calcium oxalate stones has steadily increased among males and females, whereas that of infection-related stones has significantly decreased from 26.2% to 14.3% among men over the past 50 years.

CONCLUSIONS

Nationwide surveys suggest a steady increase in the incidence of lower urinary tract stones over a 50-year period in Japan. This trend might reflect changes in the aging population and improved Japanese medical standards.

A new surgical technique: transvesical resection of prostate - case series

OBJECTIVE

To protect the urethra from instrumentation related urethra injures and stricture, we developed a new surgical technique which can be defined as transvesical resection of prostate without using urethra.

MATERIALS AND METHODS

Our study included 12 consecutive bladder outlet obstruction patients treated with transvesical prostate resection in our clinic between March 2016 and May 2016. Detailed anamnesis, results of physical examination, digital rectal examination, routine lab tests, international prostate symptoms score, transrectal ultrasound, measurement of prostate-specific antigen levels and uroflowmetry was performed in all patients prior to surgery.

RESULTS

Hospitalization period following surgery was 1 day. Foley catheter and suprapubic cystostomy catheters were removed in a median period of 3.6 days and 1 day. Median mass of resected adenomas was measured as 21.8 gr. Median maximum flow rate was measured as 6mL/s. Median postvoid residual urine volume was 70.6 cc and median international prostate symptoms score and quality of life scores were 9 and 1.4, respectively.

CONCLUSION

In this study, we would like to show the possible practicality of transvesical resection of prostate technique in this patient group. However, we think that this technique is very useful in special patient groups such as patients with bladder stones, priapism and penile prosthesis.

Familial risks in urolithiasis in the population of Sweden

OBJECTIVE

To assess detailed familial risks for medically diagnosed urolithiasis (UL, urinary tract stone disease) based on nationwide hospital and population records.

PATIENTS/SUBJECTS AND METHODS

Subjects were identified from the Swedish Multigeneration Register in which there were 211 718 patients with UL. Standardised incidence ratios (SIRs) were calculated by comparison to individuals without a family history of UL.

RESULTS

The highest familial SIRs were invariably found for the same (concordant) type of UL: 2.18 for kidney, 2.20 for ureter, and 1.93 for bladder. SIRs increased from 1.84, when one parent was affected, to 3.54 when both parents were affected, which was a multiplicative interaction. The SIR was 1.79 when one sibling was affected but it increased to 24.91 when two siblings were affected. Such excessive risks (5.2% of familial cases) are probably explained by high-penetrant genes. A low SIR of 1.29 between spouses suggested a minor contribution by shared environmental factors on the familial risk.

CONCLUSIONS

The results point to underlying genetic causes for the observed familial clustering and establish the genetic landscape of UL. Family histories should be taken in UL diagnostics and prevention could follow guidelines recommended for recurrent UL.

Unusual case of urethral steinstrasse following laser cystolitholapaxy

Urethral steinstrasse is a rare finding. This case describes a 35-year-old man presenting with urethral steinstrasse 4 weeks following laser cystolitholapaxy of a large bladder stone.

Risk factors for bladder calculi in patients with benign prostatic hyperplasia

We aim to find the risk factors that influence the formation of bladder calculi in patients with benign prostate hyperplasia (BPH) and to reduce the surgical intervention related to bladder calculi.Between January 2015 and October 2016, 332 patients with BPH underwent surgical therapy were retrospectively evaluated. Patients with BPH were categorized into 2 groups: 94 patients with bladder calculi in group 1 and 238 patients without bladder calculi in group 2. Medical history, age, body mass index (BMI), total prostate specific antigen, total prostate volume (TPV), International Prostate Symptom Score (IPSS), intravesical prostatic protrusion (IPP), urodynamic parameters, and urine culture were compared between groups.There was no significant difference in the age, BMI, peak flow rate, and total IPSS between groups. TPV, total prostate specific antigen, and duration of BPH were significantly lower in group 1 than those in group 2. In addition, IPP was significantly higher in group 1 than group 2 (P < .001). Besides, after exclusion of patients with urinary retention and indwelling catheter, group 1 associated with a significantly higher preoperative positive rate of urine culture than that of group 2 (P = .046). Multivariate analysis indicated that IPP was a significant independent risk factor for the presence of bladder calculi.The incidence of bladder calculi in patients with BPH was proved to be closely associated with preoperative positive urine culture and longer IPP in our study. Furthermore, the IPP was presented to be an independent risk factor for the formation of bladder calculi. And early antibacterial therapy of urinary tract infection (UTI) may help to prevent the presence of bladder calculi in patients with BPH.

Non-neurogenic Chronic Urinary Retention: What Are We Treating?

PURPOSE OF REVIEW

This review examines current terminology used to define non-neurogenic chronic urinary retention (CUR), describes the pathophysiology of urinary retention, and highlights contemporary diagnostic and treatment algorithms.

RECENT FINDINGS

There is no standardized definition for the condition, but volumes >300 ml are commonly used to describe CUR. It is a clinical diagnosis which does not require urodynamics. Pathophysiologic causes of CUR be from myogenic, neurogenic, bladder outlet obstruction, or a combination of these sources. Treatment algorithms recommend stratifying patients with chronic urinary retention by risk and by symptoms before initiating treatment. Common CUR outcome endpoints need to be better utilized so that treatment modalities can be compared. Non-neurogenic CUR is a heterogeneous condition that has multiple definitions, underlying physiologies, and possible endpoints. Standardization is needed to better understand and treat CUR.

The association of benign prostatic hyperplasia with lower urinary tract stones in adult men: A retrospective multicenter study

Objective

To examine the relationship between benign prostatic hyperplasia (BPH) and the presence of lower urinary tract stones.

Methods

We retrospectively reviewed the records of men with lower urinary tract stones who presented to three clinical centers in Korea over a 4-year period. We divided the patients into two groups based on the location of urinary stones: Group 1 (bladder calculi) and Group 2 (urethral calculi). We compared the characteristics of both groups and performed univariate and multivariate analyses with a logistic regression model to investigate the relationship between BPH and lower urinary tract stones.

Results

Of 221 patients, 194 (87.8%) had bladder calculi and 27 (12.2%) had urethral calculi. The mean age of Group 1 was higher than that of Group 2 (68.96 ± 12.11 years vs. 55.74 ± 14.20 years, p < 0.001). The mean prostate volume of Group 1 was higher than that of Group 2 (44.47 ± 27.14 mL vs. 24.70 ± 6.41 mL, respectively, p < 0.001). Multivariate logistic regression showed that age (OR = 1.075, 95%CI: 1.023-1.129) and prostate volume (OR = 1.069, 95%CI: 1.017-1.123) were independently associated with increased risk for bladder calculi. Upper urinary tract stones and/or hydronephrosis conferred a 3-fold risk for urethral calculi (OR = 3.468, 95%CI: 1.093-10.999).

Conclusion

Age and prostate volume are independent risk factors for bladder calculi. In addition, men with upper urinary tract disease are at greater risk for urethral calculi, which may migrate from the upper urinary tract rather than from the bladder.

Multiple Uric Acid Bladder Stones: Clinical Presentation and Endoscopic Management

Background: Bladder urinary calculi occur in 3%–8% of men with bladder outlet obstruction, and although most of them are composed of calcium, in a few cases uric acid bladder stones are diagnosed.

Case Presentation: We present clinical images and therapeutic management of a 65-year-old diabetic man with significant prostate enlargement and >30 bladder stones, the largest being 17 mm. Despite the large stone burden, the patient was managed by cystolithotripsy. Remarkably, stone composition analysis revealed 100% uric acid stone. Intraoperative and postoperative course were uneventfully.

Conclusion: Uric acid bladder stone pathogenesis seems to be multifactorial with local and systemic factors contributing in different manners and even large stone burdens may be cystoscopically managed.

Characterization of Urolithiasis in Patients Following Lower Urinary Tract Reconstruction with Intestinal Segments

PURPOSE

Urinary diversion and augmentation cystoplasty are associated with long-term complications, including metabolic derangements, infectious complications, and urolithiasis. The aim of this series was to characterize upper and lower urinary tract (LUT) calculi in this population.

METHODS

A retrospective chart review was performed on all patients with a history of urinary diversion or augmentation cystoplasty who subsequently underwent treatment for urolithiasis between January 1998 and May 2015. Data collected included demographics, perioperative characteristics, type of reconstructive procedure, urine culture, stone analysis, and metabolic evaluation. A statistical analysis was performed.

RESULTS

Ninety-nine patients were identified with a history of urolithiasis and incontinent urinary diversion (28), neobladder (21), continent cutaneous diversion (12), and augmentation cystoplasty (38). LUT stones were more common than upper tract stones in all except for incontinent diversions, which only had one lower tract stone (p = 0.0001). Twenty-three percent of stones were metabolic. Several metabolic derangements were noted, including hypocitraturia (100%), elevated urine pH (100%), low urine volume (70%), and hyperoxaluria (35%). There was a 44% rate of recurrent urolithiasis.

CONCLUSIONS

Given the high rate of stone recurrence among patients with a history of urinary diversion and augmentation cystoplasty, all measures should be taken to prevent recurrent stones. In addition to actions aimed to prevent infectious stones such as bladder and pouch irrigation, we recommend these patients undergo a full metabolic workup with targeted dietary changes and medical therapies.

Bladder stones after bladder augmentation are not what they seem

INTRODUCTION

Bladder and renal calculi after bladder augmentation are thought to be primarily infectious, yet few studies have reported stone composition.

OBJECTIVE

The primary aim was to assess bladder stone composition after augmentation, and renal stone composition in those with subsequent nephrolithiasis. The exploratory secondary aim was to screen for possible risk factors for developing infectious stones.

STUDY DESIGN

Patients treated for bladder stones after bladder augmentation at the present institution between 1981 and 2012 were retrospectively reviewed. Data were collected on demographics, surgeries and stone composition. Patients without stone analysis were excluded. Stones containing struvite, carbonate apatite or ammonium acid ureate were classified as infectious. The following variables were analyzed for a possible association with infectious bladder stone composition: gender, history of cloacal exstrophy, ambulatory status, nephrolithiasis, recurrent urea-splitting urinary tract infections, first vs recurrent stones, timing of presentation with a calculus, history of bladder neck procedures, catheterizable channel and vesicoureteral reflux. Fisher's exact test was used for analysis.

RESULTS

Of the 107 patients with bladder stones after bladder augmentation, 85 met inclusion criteria. Median age at augmentation was 8.0 years (follow-up 10.8 years). Forty-four patients (51.8%) recurred (14 multiple recurrences, 143 bladder stones). Renal calculi developed in 19 (22.4%) patients with a bladder stone, and 10 (52.6%) recurred (30 renal stones). Overall, 30.8% of bladder stones were non-infectious (Table). Among patients recurring after an infectious bladder stone, 30.4% recurred with a non-infectious one. Among patients recurring after a non-infectious stone, 84.6% recurred with a non-infectious one (P = 0.005). Compared with bladder stones, renal stones were more likely to be non-infectious (60.0%, P = 0.003). Of patients with recurrent renal calculi after an infectious stone, 40.0% recurred with a non-infectious one. No clinical variables were significantly associated with infectious stone composition on univariate (≥0.28) or bivariate analysis (≥0.36).

DISCUSSION

This study had several limitations: it was not possible to accurately assess adherence with bladder irrigations, and routine metabolic evaluations were not performed. The findings may not apply to patients in all clinical settings. While stone analysis was available for 3/4 of the stones, similar rates of incomplete stone analyses have been reported in other series.

CONCLUSIONS

In patients with bladder augmentation, 1/3 of bladder stones and >1/2 of renal stones were non-infectious. Furthermore, an infectious stone does not imply an infectious recurrent stone and no known clinical variables appear to be associated with stone composition, suggesting that there is a possible metabolic component in stone formation after bladder augmentation.

Transurethral cystolitholapaxy with the AH-1 stone removal system for the treatment of bladder stones of variable size

Background

The treatment of large volume bladder stones by current equipments continues to be a management problem in both developing and developed countries. AH-1 Stone Removal System (SRS) invented by us is primarily used to crush and retrieve bladder stones. This study evaluated the safety and efficiency of transurethral cystolitholapaxy with SRS for the treatment of bladder stones of variable size.

Methods

SRS, which was invented by Aihua Li in 2007, composed by endoscope, continuous-flow component, a jaw for stone handling and retrieving, lithotripsy tube, handle, inner sheath and outer sheath. 112 patients with bladder stones were performed by transurethral cystolitholapaxy with SRS since 2008. We compare the surgical outcome to bladder stones of variable size, and evaluate the surgical efficiency and safety.

Results

Characteristics of patients and stone removal time in variable size were evaluated. To patients with single stone, stone size was 1.35 ± 0.37 cm and the operating time was 5.50 ± 3.92 min in Group A. Stone size was 2.38 ± 0.32 cm and the operating time was 11.90 ± 9.91 min in Group B. Stone size was 3.30 ± 0.29 cm and the operating time was 21.92 ± 9.44 min in Group C. Stone size was 4.69 ± 0.86 cm and the operating time was 49.29 ± 30.47 min in Group D. The difference was statistically significant between the four groups. Among them, 74 (66.07%) patients accompanied with benign prostatic hyperplasia (BPH) were treated by transurethral resection of the prostate (TURP) simultaneously. Compared between the four groups, the difference of the TURP time was not statistically significant, P >0.05. No significant complication was found in the surgical procedure.

Conclusions

Transurethral cystolitholapaxy with SRS appears to be increased rapidity of the procedure with decreased morbidity. It is a safe and efficient surgical management to bladder stones. This endoscopic surgery best fits the ethics principle of no injury; meanwhile, the accompanied BPH could be effectively treated by TURP simultaneously.

Concurrent stone stabilization improves ultrasonic and pneumatic efficacy during cystolithopaxy: an in vitro analysis

OBJECTIVE

To identify whether stabilization of larger bladder stones would improve the efficacy of combination (ultrasonic/pneumatic) lithotripsy in a phantom bladder stone model for percutaneous cystolithopaxy.

MATERIALS AND METHODS

Using 1cm phantom Bego stones, a spherical model bladder was used to simulate percutaneous bladder access. A UroNet (US Endoscopy, USA) was placed alongside a Swiss Lithoclast probe through the working channel of a Storz 26Fr rigid nephroscope. Using a 30Fr working sheath, the stone was captured, and fragmented for 60 seconds. Resulting fragments and irrigation were filtered through a 1mm strainer, and recorded. Five trials were performed with and without the UN. Durability was then assessed by measuring net defects, and residual grasp strength of each instrument. Descriptive statistics (mean, standard deviations) were used to summarize the data, and Student's t-tests (alpha < 0.05) were used to compare trials.

RESULTS

The mean time to stone capture was 12s (8-45s). After fragmentation with UN stabilization, there were significant improvements in the amount of residual stone (22% dry weight reduction vs 8.1% without UN, p < 0.001), number of fragments (17.5 vs 5.0 frag/stone, p=0.0029), and fragment size (3.6mm vs. 7.05 mm, p=0.035). Mesh defects were noted in all nets, ranging from 2-14 mm, though all but one net retained their original grip strength (36.8N).

CONCLUSIONS

Bladder stone stabilization improved fragmentation when used in conjunction with ultrasonic/pneumatic lithotripsy. However, due to limitations in maneuverability and durability of the UN, other tools need to identified for this indication.

Cystolithotripsy using the Holmium laser: Evolving uses for the laser lithotrite

Objective:

The optimal management of bladder stones remains unclear, with a range of approaches described. We aim to describe our results using Holmium:YAG laser lithotripsy for the management of bladder stones.

Patients and methods:

Data were collected prospectively on 20 (19 male, one female) patients undergoing laser lithotripsy for bladder calculi at a single centre from February 2013 to February 2014. The mean patient age was 69.75 years (range 51–87). Patient demographics, stone size, operative details and post-operative events and hospital stay were recorded. A 365 or 550 micron Holmium:YAG laser fibre, with a power setting of 1.0J and a frequency of 10Hz was used in all cases.

Results:

The mean stone size was 2.2cm (1–4cm). The mean operative time was 32.85 min (15–70 min). Operative time correlated positively with stone size ( r=0.74). Three patients underwent laser stone fragmentation followed by transurethral resection of the prostate (TURP) during the same anaesthetic. Visibility remained clear in all these patients during lithotripsy, allowing complete fragmentation and stone clearance. Intra-operative bleeding was noted during the TURP procedure as expected. There were two episodes of self-limiting post-operative pyrexia but no reported cases of post-operative sepsis. Apart from the three patients undergoing TURP, there were no cases of post-operative bleeding and no cases required blood transfusion. Stone clearance was complete after a single procedure in 100% of cases. The mean hospital stay was 2.5 days (1–7 days), with a mean post-operative stay of 1.8 days.

Conclusion:

Laser lithotripsy offers a safe and effective management option for bladder stones, including those which are large and hard. It offers the key benefit of lithotripsy under direct vision, with no recorded mucosal injury in our series and thus no intra-operative or post-operative haematuria (outside of the TURP group).

The value of respective urodynamic parameters for evaluating the occurrence of complications linked to benign prostatic enlargement

PURPOSE

To assess the correlation between urodynamic parameters and urinary tract complications linked to benign prostatic enlargement (BPE), as well to assess the possible value of these parameters for predicting complications.

METHODS

We retrospectively analyzed the relationship between the complications and correlative urodynamic data of 486 BPH patients. Multivariate stepwise logistic regression was used to identify major independent predictors and establish regression models. Receiver operating characteristic (ROC) curves were constructed to evaluate the models' predictive values.

RESULTS

All of the individual parameters examined significantly correlated with most of the complications linked to BPE, except bladder calculus. According to ROC analysis, all of the areas under ROC curves (AUC), comparison of the individual parameters and the combined effects from the logistical regression models reached statistical significance (p < 0.05), and combining the parameters revealed a higher AUC compared to the individual parameters; however, all of the AUCs were below 0.9.

CONCLUSIONS

Urodynamic parameters are significantly correlated with most of the complications linked to BPE, and these parameters have predictive value for the occurrence of these complications with limited values.