Epidemiology of bladder stone of children: precipitating events

Risk factors for recurrence in pediatric urinary stone disease

BACKGROUND

Children's urinary system stones may develop from environmental, metabolic, anatomical, and other causes. Our objective is to determine the recurrence and prognosis, demographic, clinical, and etiological characteristics of children with urolithiasis.

METHODS

Medical records of patients were evaluated retrospectively. Patients' demographic data and medical history, serum/urine biochemical and metabolic analysis, blood gas analysis, stone analysis, imaging findings, and medical/surgical treatments were recorded.

RESULTS

The study included 364 patients (male 187). Median age at diagnosis was 2.83 (IQR 0.83-8.08) years. The most common complaints were urinary tract infection (23%) and urine discoloration (12%). Sixty-two percent had a family history of stone disease. At least one metabolic disorder was found in 120 (88%) of 137 patients having all metabolic analyses: hypercalciuria was found in 45%, hypocitraturia in 39%, and hyperoxaluria in 37%. Anatomical abnormalities were detected in 18% of patients. Of 58 stones analyzed, 65.5% were calcium and 20.6% were cystine stones. Stone recurrence rate was 15% (55/364). Older age (> 5 years), family history of stone disease, stone size (≥ 5 mm), and urinary system anatomical abnormalities were significantly associated with stone recurrence (p = 0.027, p = 0.031, p < 0.001, and p < 0.001, respectively). In adjusted logistic regression analysis, stone size ≥ 5 mm (OR 4.85, 95% CI 2.53-9.3), presence of urinary system anatomical abnormalities (OR 2.89, 95% CI 1.44-5.78), and family history of stone disease (OR 2.41, 95% CI 1.19-4.86) had increased recurrence rate.

CONCLUSIONS

All children with urolithiasis should be evaluated for factors affecting stone recurrence. Children at higher risk of recurrence need to be followed carefully.

Bladder Stones in Renal Transplant Patients: Presentation, Management, and Follow-up

INTRODUCTION

The study aim was to analyze the presentation, management, and follow-up of renal transplant patients developing bladder calculi.

METHODS

Patients who underwent renal transplant with postoperative follow-up at our institution were retrospectively analyzed (1984-2023) to assess for the development of posttransplant bladder stones. All bladder stones were identified by computerized tomography imaging and stone size was measured using this imaging modality.

RESULTS

The prevalence of bladder calculi post-renal transplantation during the study window was 0.22% (N = 20/8,835) with a median time to bladder stone diagnosis of 13 years posttransplant. Of all bladder stone patients, 6 (30%) received deceased donor and 14 (70%) living donor transplants. There were 11 patients with known bladder stone composition available; the most common being calcium oxalate (N = 6). Eleven (55%) patients had clinical signs or symptoms (most commonly microhematuria). Fourteen of the bladder stone cohort patients (70%) underwent treatment including cystolitholapaxy in 12 subjects. Of these 14 patients, 9 (64%) were found to have nonabsorbable suture used for their ureteroneocystostomy closure.

CONCLUSIONS

The prevalence of bladder stones post-renal transplant is low. The utilization of nonabsorbable suture for ureteral implantation was the main risk factor identified in our series. This technique is no longer used at our institution. Other factors contributing to bladder stone formation in this population warrant identification.

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.

Coincidental finding of a giant bladder calculus and squamous cell carcinoma of bladder: A case report

Chronic irritation of bladder by urinary bladder calculus is a known risk factor for bladder cancer. The use of Wrigley’s obstetrical forceps in general surgical practice is a rare event. Herein, we report a case of a giant urinary bladder calculus which was removed by Wrigley’s obstetrical forceps during open cystolithotomy. The bladder biopsy showed squamous cell carcinoma of the bladder. With this report, we aim to create an awareness among surgeons about the role of the Wrigley’s obstetrical forceps during open cystolithotomy, and the role of taking urinary bladder biopsy from chronically inflamed/unhealthy sites.

Ample dietary fat reduced the risk of primary vesical calculi by inducing macrophages to engulf budding crystals in mice

Although primary vesical calculi is an ancient disease, the mechanism of calculi formation remains unclear. In this study, we established a novel primary vesical calculi model with d,l-choline tartrate in mice. Compared with commonly used melamine and ethylene glycol models, our model was the only approach that induced vesical calculi without causing kidney injury. Previous studies suggest that proteins in the daily diet are the main contributors to the prevention of vesical calculi, yet the effect of fat is overlooked. To assay the relationship of dietary fat with the formation of primary vesical calculi, d,l-choline tartrate-treated mice were fed a high-fat, low-fat, or normal-fat diet. Genetic changes in the mouse bladder were detected with transcriptome analysis. A high-fat diet remarkably reduced the morbidity of primary vesical calculi. Higher fatty acid levels in serum and urine were observed in the high-fat diet group, and more intact epithelia in bladder were observed in the same group compared with the normal- and low-fat diet groups, suggesting the protective effect of fatty acids on bladder epithelia to maintain its normal histological structure. Transcriptome analysis revealed that the macrophage differentiation-related gene C–X–C motif chemokine ligand 14 (Cxcl14) was upregulated in the bladders of high-fat diet-fed mice compared with those of normal- or low-fat diet-fed mice, which was consistent with histological observations. The expression of CXCL14 significantly increased in the bladder in the high-fat diet group. CXCL14 enhanced the recruitment of macrophages to the crystal nucleus and induced the transformation of M2 macrophages, which led to phagocytosis of budding crystals and prevented accumulation of calculi. In human bladder epithelia (HCV-29) cells, high fatty acid supplementation significantly increased the expression of CXCL14. Dietary fat is essential for the maintenance of physiological functions of the bladder and for the prevention of primary vesical calculi, which provides new ideas for the reduction of morbidity of primary vesical calculi.

Which Endoscopic Methods in Prepubertal Patients with 10-20 mm Bladder Stones: Transurethral Cystolithotripsy or Percutaneous Cystolithotripsy?

BACKGROUND

The aim of this study was to evaluate the efficacy and safety of transurethral cystolithotripsy(TUC) and percutaneous cystolithotripsy(PCC) in prepubertal patients with 10-20 mm bladder stones.

MATERIALS AND METHODS

The files of patients the age of 12 and under who were admitted our clinic for bladder stones from January 2007 to January 2021 were reviewed retrospectively. Inclusion criteria were patients who were 12 years of age and under with 10-20 mm bladder stones, and who underwent endoscopic surgery(TUC or PCC). None of the patients had prior bladder or stone surgery. The patients were divided into two groups(Group 1:PCC group, and Group 2:TUC group) and collected data(preoperative, intraoperative, and postoperative characteristics) were compared between the groups.

RESULTS

This present study was enrolled 51 patients(21 patients in Group 1 and 30 patients in Group 2).The mean ages of the groups were similar (Group 1:4.7±3.6; Group 2:4.6±3.2; p:0.936). The mean stone size was 15.8±3.5 in Group 1, and 12.1±2.4 mm in Group 2. It was higher in the PCC group than TUC group(p<0.001). The operative time was lower in Group 1 than Group 2(36.4±12.9 min vs. 42.7±16.3 min, respectively), but there was no statistically significance difference between the groups (p:0.117).We achieved SFR for all the patients in both groups. Complications were observed in four (7.7%) cases. One female patient was in Group 1 and three male patients were in Group 2. There was no difference for complication rates between the groups(p:0.634).

CONCLUSIONS

Endoscopic surgeries have almost become a routine method in the treatment of bladder stones. Despite larger stone size, PCC provides similar SFR compared with TUC along with a tendency of shorter operative time. However, the use of the TUC method in toddler males could increase the risk of postoperative urinary retention. Hence, stone size and patient age should be considered in the selection of a surgical approach.

Minimally Invasive Management of Bladder Stones in Children

Background: Bladder stones (BS) are rare in children. Minimally invasive surgery (MIS) seems to be nowadays the procedure of choice to treat pediatric patients with BS. This study aimed to analyze retrospectively our experience with percutaneous cystolithotomy, endourological treatment with Holmium laser and robotic cystolithotomy in children with BS. Methods: We retrospectively analyzed the data of 13 children (eight boys and five girls) with BS who were treated at our centers between July 2013 and July 2020. The patients received three different MIS procedures for stones removal: five underwent robotic cystolithotomy, five underwent endourological treatment and three received percutaneous cystolithotomy (PCCL). We preferentially adopted endourological approach for stones <10 mm, percutaneous approach between 2014 and 2016 and robotic approach since 2016 for larger stones. Results: Mean patients' age at the time of diagnosis was 13 years (range 5-18). Ten/13 patients (76.9%) had primary BS and 3/13 patients (23.1%) had secondary BS. Mean stone size was 18.8 mm (range 7-50). In all cases the stones were removed successfully. One Clavien II post-operative complication occurred following PCCL (33.3%). All the procedures were completed without conversions. Operative time ranged between 40 and 90 min (mean 66) with no significant difference between the three methods (p = 0.8). Indwelling bladder catheter duration was significantly longer after PCCL (mean 72 h) compared with robotic and endourological approaches (mean 15.6 h) (p = 0.001). Hospitalization was significantly longer after PCCL (mean 7.6 days) compared with the other two approaches (mean 4.7 days) (p = 0.001). The endourological approach was the most cost-effective method compared with the other two approaches (p = 0.001). Conclusions: Minimally invasive management of bladder stones in children was safe and effective. Endourological management was the most cost-effective method, allowing a shorter hospital stay compared with the other procedures but it was mainly indicated for smaller stones with a diameter < 10 mm. Based upon our preliminary results, robotic surgery seemed to be a feasible treatment option for BS larger than 15-20 mm. It allowed to remove the big stones without crushing them with a safe and easy closure of the bladder wall thanks to the easy suturing provided by the Robot technology.

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.

High prevalence of pediatric urinary tract stones in Xinjiang Uyghur

The aim of the study was to report the characteristics of urolithiasis in Uyghur patients from Xinjiang, China. The composition of stones collected from 1863 patients in the Uyghur region of Xinjiang was analyzed. The median age of patients was 17 years [25th and 75th percentiles: 2, 36]. The stones were delivered by 1299 males (69.7%) and 564 females (30.3%). Calcium oxalate was the predominant stone component in 42.1% of the patients, followed by ammonium urate in 20.6%. Females had formed more stones of magnesium ammonium phosphate 8.9 vs. 5.6% (p = 0.010) and carbonate apatite 6.2 vs. 3.3% (p = 0.004). In contrast uric acid was more common in males than in females; 21.6 vs. 15.1% (p = 0.001). In this series, pediatric patients (age range 0-18) were more likely to present with a stone (51.5%, p < 0.001). Moreover, the largest number of pediatric stones was recorded in children 1-2 years old (37.9%, p < 0.001). The occurrence of ammonium urate stones was extremely high (52.4%) in children with an age below 1 year. There was a downward trend for ammonium urate with age in both children and adults (p for trend < 0.001, respectively). In contrast the frequency of uric acid declined with age in pediatric patients, but increased in adults (p for trend < 0.001, respectively). This study provides a basis for further considerations on the management of Xinjiang Uyghur patients and emphasize the severity of pediatric stone problems.

Endemic bladder calculi in children

Urinary calculi are being recognized more frequently in children and the urinary bladder is the most common site for stone formation in the lower urinary tract. Bladder calculi are grouped into three basic categories: primary idiopathic/endemic, secondary, and migrant. The incidence of vesical calculi has declined significantly in the last 70 years in developed nations owing to improvements in nutrition and socioeconomic conditions, but it is still high in developing nations. Primary idiopathic/endemic bladder calculi typically occur in children, in the absence of urinary tract infection (UTI), urinary stasis, or foreign body, and diet lacking in animal proteins is the major contributor factor. Comprehensive preventive and treatment strategies are critical for improving the quality of life of diseased children, in addition to helping to eradicate, or at least decrease, the incidence of endemic bladder calculi in developing nations.

Imaging in the diagnosis of pediatric urolithiasis

Pediatric urolithiasis is an important and increasingly prevalent cause of pediatric morbidity and hospital admission. Ultrasound (US) is the recommended primary imaging modality for suspected urolithiasis in children. There is, however, widespread use of CT as a first-line study for abdominal pain in many institutions involved in pediatric care. The objective of this review is to outline state-of-the-art imaging modalities and methods for diagnosing urolithiasis in children. The pediatric radiologist plays a key role in ensuring that the appropriate imaging modality is performed in the setting of suspected pediatric urolithiasis. Our proposed imaging algorithm starts with US, and describes the optimal technique and indications for the use of CT. We emphasize the importance of improved communication with a greater collaborative approach between pediatric and general radiology departments so children undergo the appropriate imaging evaluation.