A single-center clinical study of 61 children with ammonium urate stones / 现代泌尿外科杂志

【Objective】 To analyze the clinical characteristics of children with ammonium urate stones in Xinjiang, so as to provide reference for the prevention and treatment of this disease. 【Methods】 The clinical data of all children with ammonium urate stones admitted to the People’s Hospital of Xinjiang Uygur Autonomous Region from 2016 to 2021 were retrospectively analyzed, including age, sex, body mass index, stone site, stone size, stone component, urine pH, urine culture and biochemical examination results. The serum total protein, albumin, sodium, potassium, calcium, magnesium, uric acid and urine pH were compared between the pure and mixed groups. 【Results】 A total of 61 children (31.6%) had ammonium urate stones, their average age was (4.05±3.37) years, and the male to female ratio was 2.21∶1. Among them, there were 37 cases (60.7%) of renal calculi and 50 cases (82.0%) of upper urinary calculi. The most common component of mixed ammonium urate stones was calcium oxalate, including calcium oxalate monohydrate, calcium oxalate monohydrate and calcium oxalate dihydrate. Compared with mixed type, children with pure stone type had a younger age (P=0.001) and a smaller stone size (P=0.003). Positive urine culture was detected in 14 cases (23.0%), 7 of which (50% were infected with Escherichia coli, and 11 (78.6%) with non-urease bacteria. 【Conclusion】 Non-urease bacteria are the main pathogens of urinary tract infection in children with ammonium urate stones. The incidence is higher in boys, and the most common stone location is upper urinary tract. Calcium oxalate is the most common mixed component. Pure type is more common in young children and the stones are relatively small.

Analysis of stone composition and clinical characteristics of urinary calculi in infants in Xinjiang / 国际外科学杂志

Objective:To analyze the composition and clinical characteristics of urinary calculi in infants in Xinjiang.Methods:The clinical data of 75 infants with urinary calculi admitted to the People′s Hospital of Xinjiang Uygur Autonomous Region from January 2016 to December 2021 were retrospectively analyzed, including the general situation of the children, stone-related parameters, random urine pH value, urine culture and biochemical examination results. The serum uric acid, serum calcium, urine pH value, positive rate of urine culture, and stone length between infants with and without ammonium urate stones were compared. Measurement data conforming to normal distribution were expressed as mean ± standard deviation ( ± s), and independent sample t-test was used for inter-group comparison. Measurement data that did not conform to the normal distribution were expressed as the median (interquartile distance) [ M ( Q1, Q3)], and Mann-Whitney U test was used for comparison between groups. The Chi-square test, continuity-corrected Chi-square test or Fisher exact probability method were used for the comparison of count data. Results:The median age of infants with urinary calculi was 23.04 months, and the ratio of male to female was 3.2∶1. More than half of the infants (81.3%, 61/75) came from rural areas, 57.3% (43/75) were malnourished, 33.3% (25/75) were complicated with urinary tract infection, and 8.0% (6/75) were combined with urinary system congenital malformation. The calculi were found in 53 cases (70.67%) of kidney, 27 cases (36.0%) of ureter, 17 cases (22.67%) of urethra and 16 cases (21.33%) of bladder. The analysis of calculi composition showed that there were 44 cases (58.67%) of ammonium urate, 39 cases (52.0%) of calcium oxalate, 14 cases (18.67%) of apatite carbonate and 7 cases (9.33%) of uric acid. Kidney calculi was more common in female infants ( P=0.011). Compared with the infant group ( n=19), calcium oxalate stones were more common in the preschooler group ( n=56) ( P=0.039), but there were not statistical difference in the incidence of ammonium urate, apatite carbonate and uric acid stones. There were not statistical difference in gender, age, place of residence, nutritional status, serum uric acid, serum calcium, urine pH value, positive rate of urine culture, stone maximum diameter and incidence of bladder stones between ammonium urate group and non-ammonium urate group. Conclusions:The incidence of urinary calculi in infants is higher in boys, and the most common site of calculi is the upper urinary tract, especially in female kidney calculi. Ammonium urate is the main component of urinary calculi in infants. Calcium oxalate stones are more common in preschooler group. Infants with urinary calculi are mostly rural residents, and malnutrition and urinary tract infection are more common.

Comparison of super-mini-PCNL and flexible ureteroscopy for the management of upper urinary tract calculus (1-2 cm) in children.

OBJECTIVES: To retrospectively evaluate the efficacy and safety of super-mini percutaneous nephrolithotomy (SMP) and retrograde intrarenal surgery (RIRS) for children with upper urinary tract calculus (1-2 cm). PATIENTS AND METHODS: Children with upper urinary tract calculus (1-2 cm) who underwent the SMP or RIRS were enrolled in this study. Patients were divided into two groups: group SMP, 36 patients; and group RIRS, 25 patients. Patients were evaluated with KUB radiography or CT after 1 month. The collected data were analyzed. RESULTS: The mean stone size was 14.18 mm in group SMP, and 14.00 mm in group RIRS (p = 0.812). Group RIRS compared to group SMP showed longer operating time [76.3 vs 53.9 min (p = 0.002)], and postoperative hospital stay [4.2 vs 2.9 days (p = 0.011)]. The overall stone-free rate (SFR) was 94.4% for group SMP, and 60.0% for group RIRS in 1 month after operation (p = 0.001). The re-treatment rate was significantly higher in group RIRS compared to group SMP [20.0% vs 0.0% (p = 0.009)]. The complication rate was 5.6%, and 24.0% for groups SMP, and RIRS, respectively (p = 0.036). CONCLUSIONS: SMP was more effective than RIRS to obtain a better SFR, less re-treatment rate, and complication rate in children with upper urinary tract calculus (1-2 cm).

Clinical application of super-mini PCNL (SMP) in the treatment of upper urinary tract stones under ultrasound guidance.

PURPOSE: To present the safety and efficacy of totally ultrasonography-guided Super-mini percutaneous nephrolithotomy (SMP) in the treatment of upper urinary tract stones both in children and adults. PATIENTS AND METHODS: We carried out SMP in 104 patients (including 48 children and 56 adults) with upper urinary tract stones between June 2015 and February 2017. All steps of renal access were performed by ultrasonography. The lithotripsy was performed using either Holmium laser or pneumatic lithotripter. Perioperative and postoperative parameters along with operative data were recorded in detail. RESULTS: The mean age of children and adult patients were 4.4 ± 3.6 and 44.3 ± 15.7 years old, respectively. The stone burden was comparable for both groups (1.72 ± 0.66 vs 1.74 ± 0.56 cm, p = 0.852). Mean operation time was not significant different between two groups (p = 0.052), while the mean haemoglobin drop in children was much lower in adult patients (6.3 ± 6.9 vs 10.9 ± 8.69, p = 0.004). Both groups had similar SFRs in postoperative 1 day and at 1-month follow-up (p = 1.000, p = 0.912). Mean hospital stay of children and adult patients was 2.3 ± 0.8 and 2.2 ± 0.76 days (p = 0.484). The total complication rate was significantly lower in two groups (p = 1.000); none of the patients required blood transfusion. CONCLUSIONS: Ultrasonography-guided SMP was a safe and effective treatment option for moderate-sized upper urinary tract stones, and has the advantage of preventing radiation hazard, especially for pediatric stone patients.

Super mini-percutaneous nephrolithotomy (SMP) by ultrasound-guided for pediatric kidney stones / 中华泌尿外科杂志

Objective To evaluate the safety and efficacy of super mini-percutaneous nephrolithotomy (SMP) by ultrasound-guided renal access in pediatric with renal calculus.Methods From May to August 2015, 20 pediatric patients with upper tract stones underwent the SMP by ultrasound guidance.The patients aged 11-144 months , median age 31.5 months, The stone size ranged 0.8-2.5 cm, mean(1.48 ±0.59) cm.Among the 20 children, single pelvis stones were in 8, multiple stones in 10 and upper ureter stones in 2.All patients had no previous surgery treatment.The SMP system consists of a F6.0 -7.5 nephroscope and a modified F12-14 access sheath with suction-evacuation function.Nephrostomy tract dilation was performed up to F12-14 and lithotripsy procedure was performed by using pneumatic lithotripter.Nephrostomy tube or double J stent was placed only if clinically indicated.Results The stone size was 0.8-2.5 cm ,mean (1.48 ± 0.59)cm.Among the 20 children, there were 8 patients with single pelvis stone, 10 with multiple stones and 2 with upper ureter stones.All the patients were completed successfully without surgery conversion.Mean operative time ranged 6-40 minutes ,mean(17.6 ± 11.6) minutes.The stone free rate was 100％ after the evaluation in the postoperative day.The hemoglobin drop was 2-16 g/L,mean (7.6-± 4.1) g/L.No major complications occurred, neither patient required transfusion.The tubeless PCNL without double J stents and nephrostomy tubes placed were achieved in all patients.Only 14 patients had a ureter catheter placement for one day.The average hospital stay ranged 1-4 days, mean (2.4 ± 0.8) days.Conclusions SMP could be a safe and effective treatment for kidney stone up to 2.0 cm in pediatric cases with advantages of short recovery time, high stone free rate and no catheter placement.SMP could be the ideal procedure for children with upper urinary tract calculus.