Urolithiasis analysis in a multiethnic population at a tertiary hospital in Nairobi, Kenya

Prevalence and clinical patterns of urolithiasis in sub-saharan Africa: a systematic review and meta-analysis of observational studies

BACKGROUND AND OBJECTIVE

Urolithiasis, the presence of stones in the urinary tract, has been linked to various clinical features and reported as a worldwide health concern. Its prevalence varies across different regions as well as populations. Several primary studies have been conducted in Sub-Saharan Africa on the situation. However, their reports are inconsistent. Hence, this review aimed to assess the pooled magnitude of urolithiasis and its clinical patterns among hospital-visiting patients in sub-Saharan Africa.

METHODS

Online databases such as PubMed, Hinari, the African Journals online database, and Google Scholar were used to comprehensively search articles published until June 28, 2023, about the prevalence and clinical patterns of urolithiasis in Sub-Saharan Africa. All the included studies were conducted at hospital setting. The retrieved data was exported to STATA version 16 for final analysis. A random-effect meta-analysis model was computed to estimate the pooled results. The heterogeneity of the studies was assessed using I2 and Cochran's Q. Publication bias was examined by observation using funnel plots and statistically by Egger's tests. Subgroup analysis was performed based on the country where the studies have been conducted.

RESULT

A total of 26 articles (11 reported both prevalence and clinical pattern, 5 reported only prevalence, and 10 reported only clinical patterns of urolithiasis) were included in the final systematic review and meta-analysis. The pooled prevalence of urolithiasis among hospital-visiting patients was 9.4% (95% CL = 4.9-14%), with significant heterogeneity. Most of the urolithiasis was located in the kidney, with an estimated pooled proportion of 4.6% (95% CI = 2.7, 6.5), followed by bladder stone-2.0% (95% CI = 0.7, 3.4), ureteral stone-1.8% (95% CI = 0.7, 2.9), and urethral stone-0.2% (95% CI = 0.00, 0.05). The subgroup analysis showed the highest prevalence of urolithiasis was found in Mauritian, 28.1% (95%CI 24.5, 31.7), followed by Ethiopia 18.1%, and the lowest was in Eritrea, 1.0%. A sensitivity analysis using the random-effects model found no influential study on the pooled prevalence of urolithiasis. Evidence of significant publication bias was observed and trim-fill analysis was conducted for adjustment. Accordingly, two missing studies were identified, and after adjustment, the combined prevalence of urolithiasis was estimated to be 10.7%. The study also found that urolithiasis prevalence per gender was 6.3% in males and 2.9% in females. The most common clinical presentation of urolithiasis was flank pain at 58.4% (95% CL=, 45.9, 70.8), followed by low back pain at 45.9% (95% CL=, 23.1, 68.8), and nausea/vomiting at 29.9% (95% CI: 1 1.1, 48.8).

CONCLUSION

The prevalence of urolithiasis in Sub-Sahara African Countries is increasing even though a remarkable regional variation was observed, with higher predominance in males than females. Common clinical presentations of urolithiasis were flank pain, low back pain, and nausea/vomiting.

Analysis, treatment modality and demographic characteristics of urolithiasis patients visiting Korle-Bu Teaching Hospital in Ghana

Background

Globally urolithiasis is on the rise and gradually becoming a public health concern due to the associated complications. This study reviewed the demographic characteristics, the chemical composition of stones, treatment modality and duration of hospitalisation of urolithiasis patients at Korle-Bu Teaching Hospital, Accra, Ghana.

Materials and Methods

This was a retrospective study conducted between March 2019 and April 2022. Data from consecutive patients treated for urolithiasis were used for this study. Data on demographic characteristics, stones chemical composition, urine factors, urolithiasis treatment modality and duration of hospital stay after therapy were collated and analysed using descriptive and inferential approaches.

Results

The age of the patients ranged from 2 to 75 years with a mean of 45 (±13.4). The predominant age group for stone formation was 30-39 years - 52(26.3%). Urolithiasis was common among patients in the formal employment sector: 81(40.9%). All stones had two or more chemical compositions, with the combination of calcium oxalate monohydrate, calcium oxalate dihydrate and uric acid being the predominant stone type: 88(57.5%). Ureteroscopy with semi-rigid and Percutaneous nephrolithotomy were the predominant treatment modalities: 105(53.0%) and 74(37.4%), respectively. Escherichia coli was responsible for most urinary tract infections in urolithiasis patients 8(4.0%) and the least duration of hospital stay after the procedure was associated with the use of semi-rigid ureteroscope as the treatment modality with a median duration of 2 days (1-2 days) with P < 0.0001.

Conclusions

Urolithiasis was predominant among professionals in the formal sector. All stones were mixed with Calcium oxalate monohydrate, calcium oxalate dihydrate, and uric acid combination being the majority. Ureteroscopy with semi-rigid and percutaneous nephrolithotomy were the common treatment modality.

Nur MA, Mohamed FY, Mohamud AK, Hassan J. The prevalence of urolithiasis in subjects undergoing computer tomography in selected referral diagnostic centers in Mogadishu, Somalia

Introduction and objectives

Somalia was predicted to be in the global stone belt with high urolithiasis prevalence. We aimed to determine the prevalence of urolithiasis and their demographic and computer tomography (CT) characteristics among subjects under CT scans in Mogadishu, Somalia. Materials and Methods: From March 2014 to November 2022, a total of 7,276 patients who underwent an abdominopelvic non-contrast CT scan for various indications were retrospectively reviewed. The mean age was 45.6 years with a standard deviation of 21.1 (range, 0.2-110 years). Patients were subdivided into two categories: adults (≥18 years) and pediatric (≤17 years).

Results

Of the 7,276 patients, 1,075 (14.8%) were diagnosed with urolithiasis. Among those with urolithiasis, 702 (65.3%) were male patients, and 373 (34.7%) were female patients. Among them, adults accounted for 92.7%, while children were 7.3%. Renal stones (nephrolithiasis) were the most common, representing 57% followed by ureteric stones at 35.5%, making upper urinary stones 92.5%. Approximately 70 patients (6.5%) had bladder stones; of these, 26 of them (37%) were accompanied by benign prostatic hyperplasia (BPH). There were 10 urethral stones (0.9%) recorded in the study, all were found in male patients, 8 localized in prostatic urethra, and 2 in the bulbar urethra. The overall mean stone size was 13.2 mm, and 60% of them ranged from 5 to 22 mm. Only 24% of the patients were asymptomatic. Single stones were almost 70%, while staghorn calculi were 8.2%. More than 60% of the patients with urolithiasis showed some degree of hydronephrosis ranging between mild to severe.

Conclusion

A CT scan-based urolithiasis prevalence indicates 14.8% in Mogadishu, Somalia, and these results are consistent with the probability calculation of the weights-of-evidence (WofE) methodology based on several risk factors including temperature, climate change, mineral deposit, drinking water quality, and distribution of carbonated rocks. Considering the high prevalence of the disease, Somalia needs to invest more in prevention and treatment facilities while also training urologists that are capable of utilizing minimally invasive techniques in the country.

Anti-urolithiatic Activity of Daidzin in Ethylene Glycol-Induced Urolithiasis in Rats

Urolithiasis is a common urological disorder, which causes considerable morbidity in both genders at all age groups worldwide. Though treatment options such as diuretics and non-invasive techniques to disintegrate the deposits are available, but often they are found less effective in the clinics. In this work, we planned to investigate the ameliorative effects of daidzin against the ethylene glycol (EG)-induced urolithiasis in rats. The male albino rats were distributed into four groups (n = 6) as control (group I), urolithiasis induced by the administration of 0.75% EG (group II), urolithiasis induced rats treated with 50 mg/kg of daidzin (group III), and urolithiasis rats treated with standard drug 750 mg/kg of cystone (group IV). The urine volume, pH, and total protein in the urine were assessed. The activities of marker enzymes in both plasma and kidney tissues were analyzed using assay kits. The levels of kidney function markers such as calcium, oxalate, urea, creatinine, uric acid, magnesium, BUN, and phosphorous were estimated using assay kits. The status of antioxidants and inflammatory cytokines were also examined using kits. The renal tissues were examined by histopathological analysis. Our results revealed that the daidzin treatment effectively decreased the urine pH and protein level and increased the urine volume in the urolithiasis rats. Daidzin decreased the calcium, oxalate, uric acid, and urea, creatinine, and BUN levels and also improved the magnesium and phosphorus in the urolithiasis rats. The activities of AST, ALT, ALP, GGT, and LDH were effectively reduced by the daidzin in both serum and renal tissue. Daidzin also reduced the inflammatory marker and increased the antioxidant levels. Histopathology results also proved the therapeutic effects of daidzin. Together, our results displayed that daidzin is effective in the amelioration of EG-induced urolithiasis in rats.

Composition of Uroliths seen in patients in Abuja, Nigeria: a single centre retrospective analysis of 155 stones

Background

Uroliths are stones formed in the urinary tract. Analysis of stones helps to identify risk factors for their development and prevention of recurrence. Standard stone analysis using modern technology is not routinely done in Nigeria. This study sought to determine the chemical composition of urinary stones seen in Abuja, Nigeria.

Methods

This was a retrospective study on composition of uroliths. Urinary stones surgically removed from 155 patients through minimal access surgical procedures between January 2015 and August 2019 were analysed. Optical crystallography and infrared spectroscopy were used to determine the chemical composition of the urinary stones.

Results

A total of 155 urinary stones were assembled from the patients. More stones were removed from male patients and the male to female ratio was 1.9:1. Stones were rare in the extremes of age. The predominant location (89.7%) of stones was in the upper urinary tract. All stones were of mixed composition with calcium oxalate accounting for 93.55%. Calcium oxalate, calcium phosphate and uric acid stones were more common in the upper tract, while 2 of the 3 struvite stones were found in the lower tract.

Conclusion

Stones found in this study were of mixed composition with the most common constituent being Calcium oxalate and the least common, struvite.

Urolithiasis: Presentation and Surgical Outcome at a Tertiary Care Hospital in Ethiopia

Background

The prevalence of urolithiasis is on a rising trend in tropical and sub-Saharan African countries. The treatment options and data on the surgical outcome are limited in our country. This study was designed to assess the clinical presentation, surgical management and outcome of patients operated on for urolithiasis.

Patients and Materials

A retrospective study of all patients admitted and operated for urolithiasis at St. Paul’s hospital millennium medical college (SPHMMC) from July, 2016 to December, 2017 was conducted. Factors associated with surgical outcome were identified with binary logistic regression.

Results

Urolithiasis constituted 247 (30.0%) of 824 urologic admissions. Of these, 202 (Male:Female = 2:1) patients were investigated. The mean age was 37.1 ± 14.4 years (range, 10–85 years). The mean duration of illness was 16.7 ± 18.7 months and the commonest presenting symptom was isolated flank pain (97, 48.0%). A majority of the patients (186, 92.1%) had upper tract stones of which 96 (51.6%) were renal stones. More than two-thirds (164, 81.2%) of the patients had complications at presentation, and hydronephrosis (148, 73.3%) was the major one. Half of the patients (104, 51.5%) were treated with endoscopic procedures, 88 (43.6%) with open stone surgery and in 10 (4.9%) patients both were performed. Nephrectomy was done to 15 (7.4%) patients. Intraoperative and postoperative complications were noted in 16 (7.9%) and 26 (12.9%) patients, respectively. These complications were higher in patients with comorbid illness (AOR = 2.44; 95% CI 1.12–5.31; p = 0.024). Complete stone clearance was achieved in more than half of the clients (114, 61.0%). Multiple stones (AOR = 8.33; 95% CI 2.53–27.43; p < 0.0001) and endoscopic procedures (AOR = 4.17; 95% CI 1.57–10.71; p = 0.003) had significant association with incomplete stone clearance.

Conclusion

Patients’ presentation in this review was not different from studies elsewhere. Endoscopic procedures are emerging in our set up; however, it was significantly associated with incomplete stone clearance. Strategies to improve outcome (stone clearance) need to be implemented accordingly.

Uric Acid and Urate in Urolithiasis: The Innocent Bystander, Instigator, and Perpetrator

Uric acid is an end product of purine metabolism in human beings. An unusual and still unexplained phenomenon is that higher primates have relatively high uric acid levels in body fluids owing to a combination of absence of degradation and renal retention. The physiologic purpose of high uric acid levels still is enigmatic, but the pathobiologic burden is a variety of crystallopathies owing to the low aqueous solubility of uric acid such as gouty arthritis and acute uric acid nephropathy. In the urinary space, three distinct conditions result from chronic uric acid and/or urate precipitation. The first and most common variety is uric acid urolithiasis. In this condition, urate is a victim of a systemic metabolic disease in which increased acid load to the kidney is coupled with diminished urinary buffer capacity owing to defective ammonium excretion, resulting in titration of urate to its sparingly soluble protonated counterpart, uric acid, and the formation of stones. Uric acid is the innocent bystander of the crime. The second variety is hyperuricosuric calcium urolithiasis, in which uric acid confers lithogenicity via promotion of calcium oxalate precipitation by multiple mechanisms involving soluble, colloidal, and crystalline urate salts. Uric acid is the instigator of the crime. The third and least common condition involves urate as an integral part of the urolith as an ammonium salt driven by high ammonium and high urate concentrations in urine. Here, uric acid is one of the perpetrators of the crime. Both known and postulated pathogenesis of these three types of urolithiasis are reviewed and summarized.

Surgical Management of Urolithiasis of the Upper Tract - Current Trend of Endourology in Africa

Urolithiasis is a global pathology with increasing prevalence rate. The lifetime recurrence of urolithiasis ranges from 10–75% creating a public health crisis in affected regions. The epidemiology of urolithiasis in most parts of Africa and Asia remains poorly documented as incidence and prevalence rates in these settings are extrapolated from hospital admissions. The surgical management of kidney and ureteral stones is based on the stone location, size, the patient’s preference and the institutional capacity. To date, the available modalities in the management of urolithiasis includes external shock wave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL), ureterorenoscopy (URS) including flexible and semirigid ureteroscopy. However, regarding the lack of endourological equipment and expertise in most parts of Sub-Saharan Africa (SSA), most urological centers in these regions still consider open surgery for kidney and ureteral stones. This review explores the current trend and surgical management of upper tract urolithiasis in SSA with insight on the available clinical guidelines.

Evaluation of the composition of urinary tract stones in children from the Inner Western Anatolian Region in Turkey

OBJECTIVE

Pediatric urolithiasis is a globally growing problem. The composition and frequency of urinary tract stones vary not only among different countries, but across various regions in a country. Hence, we aimed to identify the types and frequencies of urinary tract stones in children from our region (Inner Western Anatolian part of Turkey), and to compare our findings with the results from other regions in our country.

MATERIAL AND METHODS

In this retrospective analysis of 53 pediatric urolithiasis cases that were treated in our hospital between 2009 and 2019, the demographic data, clinical course, radiological and metabolic findings, the recurrence rate, and the composition of the stones were evaluated.

RESULTS

The mean age of the patients was 5.9±4.6 (0.5-18) years, and there were 30 (56.6%) girls and 23 (43.4%) boys. An analysis of the composition of the stones revealed that the majority (85%) consisted of calcium oxalate. The highest risk of recurrence and the need for multiple shockwave lithotripsy (SWL) sessions or surgical intervention appeared to be related with the presence of whewellite stones, which are the most challenging stones in childhood.

CONCLUSION

According the study results, the urinary stone types vary across different regions in our country, and the frequency of uric acid stones decreased going westward, while the frequency of oxalate stones increased. We conclude that this difference in the frequency of the type of urinary stones might reflect the regional dietary habits. Regional frequency and etiology studies for the types of urolithiasis may facilitate the approach to the treatment of urolithiasis.

Composition of uroliths in a tertiary hospital in South East Nigeria

Background

Urolithiasis affects primarily the urinary tract and complications as debilitating as renal failure may develop. Determining the chemical composition of uroliths can aid management and prevention of recurrence in patients.

Objective

To determine the chemical composition and anatomical distribution of uroliths in Nigeria.

Methods

This descriptive cross-sectional study was conducted between March 2014 and February 2016, in a tertiary hospital in Nigeria. We reviewed the outcomes of uroliths of adult patients sent to our laboratory for chemical analyses. Samples were analyzed using simple qualitative tests.

Results

52 adult patients were included with a mean age (SD) of 46.6 (12.6) years. Males (76.9%) were more affected than females (23.1%). For both sexes, highest occurrence of stones was in bladder (85.7%). Calcium-containing stones had the highest occurrence (85.2%) and predominated in the renal, ureter and urethra, followed by struvite stones (59.5%). In the bladder, struvite stones were predominant (85.8%), with calcium-containing stones accounting for 71.4%.

Conclusion

This study showed that struvite and calcium phosphate-containing stones constitute majority of uroliths in our setting with low occurrence of calcium oxalate stones. This indicates that urinary tract infection most likely plays a substantial role in the formation of uroliths in Nigerians. Modern methods of stone analysis is advocated to further define management options.