Management of pediatric lower urinary tract stones in Saiful Anwar hospital Malang, Indonesia

Management of pediatric lower urinary tract stones in Saiful Anwar hospital Malang, Indonesia

I Made Udiyana Indradiputra¹, Besut Daryanto^1,&

¹Department of Urology, Brawijaya University, Saiful Anwar General Hospital, Malang 65145, East Java, Indonesia

^&Corresponding author
Besut Daryanto, Department of Urology, Brawijaya University, Saiful Anwar General Hospital, Malang 65145, East Java, Indonesia

Introduction    

The pediatric stone disease causes considerable morbidity, even though it occurs less often than in adults. The proportion of patients with the pediatric stone disease is consistently different by region. Different regions will have different stone types and patient demographics as an underlying pattern [1]. The incidence of pediatric lower urinary tract stones is 1.1 per 1000 pediatric patients per year and accounts for about 2.2% of all stone disease cases in Saiful Anwar Hospital Malang, Indonesia. The lower urinary tract is still the predominant stone location for pediatric stone disease (71.1% of all pediatric stone patients). The management of pediatric lower urinary tract stone patients in Saiful Anwar Hospital has tended to shift from an invasive approach (open) to a less invasive approach (percutaneous). In order to learn more about the pattern of lower urinary tract stones in pediatric patients, a retrospective study was conducted. The aim of this study was to describe and analyze the characteristics of pediatric lower urinary tract stone disease (bladder and urethra) in Saiful Anwar Hospital Malang, Indonesia.

Patient and observation     

Data for 114 pediatric stone disease patients treated at Saiful Anwar Hospital between January 2004 and December 2015 were retrospectively collected, including 81(71.1%) cases of pediatric lower urinary tract stone disease, which were specified into 78(68.4%) cases of bladder stones and three (2.6%) cases of ureteral stones. The patients were divided into five age groups: toddler (13-24 months old), early childhood (2-5 years old), middle childhood (6-11 years old), early adolescence (12-18 years old) and late adolescence (19-21 years old). The data for lower urinary tract stone disease were then described and analyzed based on demographic characteristics, body mass index (BMI), stone diameter, management, length of hospitalization and stone analysis results. BMI was categorized by using a CDC graphic for BMI percentile. Normality of data distribution was analyzed by Kolmogorov-Smirnov test (n > 50). Analysis of compared means was carried out for the length of stay for each management option. A non-parametric test (Mann-Whitney U test) was used due to abnormal distribution of the data. A p-value < 0.05 was considered to be statistically significant. The number of bladders and urethral stone cases in Saiful Anwar Hospital varied in every age group. Those with bladder and urethral stones were predominantly male in every age group except the first 5 years of life which was dominated by females. The peak rate of lower urinary tract stones was at 2-5 years old (37%). Most of the patients sought medical attention due to uncomfortable voiding (39.2%) or urinary retention (27.1%). Other modes of presentation were an abdominal/flank pain (13.6%), fever (2.5%), blood in the urine (2.5%) and a combination of symptoms (14.8%) (Figure 1). The mean of patients' BMI was 18.7 ± 3.5 kg/m². Seventy-four percent of patients had a normal BMI, 11% of patients were underweight and 16% of patients were overweight (Figure 2). Most bladder stone patients were treated by open vesicolithotomy (57 patients/70.4%) instead of percutaneous vesicolithotripsy (21 patients/25.9%). Urethral stone patients were initially treated by posterior lubrication, and treatment continued with percutaneous vesicolithotripsy in two (2.5%) patients (one/33.3% by anterior lubrication). Mean stone size was 29 ± 22 mm. Mean stone size for patients treated with open vesicolithotomy was 32.1 ± 14 mm; for those treated by percutaneous vesicolithotripsy it was 18 ± 6 mm (Table 1, Table 2). The length of hospitalization for open vesicolithotomy patients was 8 ± 3 days, which was significantly longer (p = 0.006) than that for percutaneous vesicolithotripsy patients (5 ± 2.3 days). Three (13%) percutaneous vesicolithotripsy patients needed secondary treatment (vesicolithotomy) (Figure 3). The most common constituent of stones was calcium oxalate (35.8%), followed by magnesium ammonium phosphate (27.2%). Other stone constituents were ammonium acid urate (17.2%) and mixed composition (19.8%).

Discussion     

In most developed countries, there is a tendency of migration from lower tract to upper tract stone cases [1]. Lower urinary tract stones in children occur commonly in developing countries with a population of low socioeconomic status, including Indonesia [2-4]. Lower urinary tract stone disease is still predominant in cases of the pediatric stone disease in Saiful Anwar Hospital, accounting for 71.1% of all pediatric stone patients. Children who have a diet low in protein and phosphates, especially patients with a low economic status, have a higher risk of having bladder stones [1, 5]. Climate and disease characteristics may also affect the pattern of lower urinary tract stone disease in children [1]. Children who are dehydrated due to hot weather or diarrhea may have increased incidence of stone disease in Indonesia, including in Malang, East Java. In Saiful Anwar Hospital, it was found that the peak rate of lower urinary tract stones was at the age of 2-5 years (early childhood). Based on the SIU-ICUD joint consultation on stone disease in 2015, the peak incidence of bladder stones is at the age of 3 years [1]. In Saiful Anwar Hospital, we found that most patients with lower urinary tract stones were male in every age group, except for the first 5 years of age which was dominated by females. Most of our patients had a normal range of BMI (72.8%), and 14.8% of our patients were overweight. No positive association of stone disease with BMI was found in other studies [1]. The mode of presentation of pediatric lower urinary tract stone disease in Saiful Anwar Hospital was different among patients. Uncomfortable voiding was the most common initial presentation (39.5%), especially in older patients, followed by urinary retention (27.1%). This is similar to the results of other studies that found acute urinary retention and voiding symptoms as the most common initial presentation [4, 6]. Pediatric patients are different from adult patients: they are still unable to communicate and understand their symptoms. Thus, diagnosis needs to be confirmed by radiologic examination using plain radiography, ultrasonography or intravenous urography if necessary. Open vesicolithotomy has been used as the traditional method of treatment for pediatric bladder stones. It has inherent problems of a long scar, prolonged catheterization, extended hospitalization and risk of infection [6]. The majority of bladder stones in adults can now be treated urethrally by using electrohydraulic, ultrasonic or pneumatic lithotripsy. However, the use of these devices is restricted to pediatric patients, especially boys, because of the narrow caliber of the urethra and concern of iatrogenic urethral stricture [6, 7]. A percutaneous suprapubic approach is a safe alternative for a narrow urethra in these situations [8]. In Saiful Anwar Hospital, most bladder stone patients were treated by open vesicolithotomy (70.4%) instead of percutaneous vesicolithotripsy (25.9%). Urethral stone patients were treated by posterior lubrication, and treatment was continued by percutaneous vesicolithotripsy in two (66.7%) patients (one/33.3% patient had the stone removed only by anterior lubrication). Mean stone size for all treatments was 29 ± 22 mm. Mean stone diameter for patients treated with open vesicolithotomy was larger (32.1 ± 14.2 mm) than that for patients treated by percutaneous vesicolithotripsy (18 ± 6mm). Initially, open vesicolithotomy was considered for large stones. However, since there are a new lithotripter and laser that are able to break larger stones, cases of open surgery have decreased lately. In the last 2 years, all pediatric bladder stones have been treated by percutaneous vesicolithotripsy.

Percutaneous vesicolithotripsy can be performed quickly, and this technique is also more advantageous than open surgery regarding cosmetic outcome and length of hospital stay [6]. We found that the length of hospitalization for pediatric open vesicolithotomy patients in Saiful Anwar Hospital was 8 ± 3 days, which was significantly longer (p = 0.006) than that for percutaneous vesicolithotripsy patients (5 ± 2.3 days). From a study of 155 children aged 8 months to 14 years with bladder stones ranging in size from 0.7 to 4 cm treated with percutaneous vesicolithotripsy, Salah et al. [8] concluded that percutaneous vesicolithotripsy is a safe and effective method for the treatment of endemic bladder stones, and it is found to reduce morbidity, hospital stay and cost of treatment. In our hospital, there was no documented intraoperative complication found in treatment using vesicolithotomy or percutaneous vesicolithotripsy. However, three (13%) lithotripsy patients needed secondary treatment (vesicolithotomy). Other studies found that open vesicolithotomy seems to be safer; however, they conclude that open and endourological management of vesical stones in children is efficient, with low incidence of complications [6, 9]. In our study, the most common constituent of stones was calcium oxalate (35.8%), followed by magnesium ammonium phosphate (27.2%). Other stone constituents were ammonium acid urate (17.2%) and mixed composition (19.8%). From the literature, it was found that ammonium urate and calcium oxalate are the most common stone constituents [1, 10]. However, not all pediatric stones were analyzed in our study due to incomplete data. Better stone analysis recording and metabolic stone evaluation for all pediatric stone patients need to be performed to get a better conclusion regarding stone etiology and to have a more detailed description of pediatric lower urinary tract stone disease in Malang, Indonesia (Figure 4).

Conclusion     

Based on our study, we can conclude that pediatric lower urinary tract stone patients in Saiful Anwar Hospital Malang Indonesia are predominantly male, with a peak rate in early and middle childhood. An endourological procedure (percutaneous vesicolithotripsy) offers a shorter hospital stay than open vesicolithotomy. Further investigation and better database collection is needed in the future, to have more a detailed description of pediatric lower urinary tract stone disease in Malang, Indonesia.