Ureteral junction obstruction (UPJO) is the most common cause of congenital obstructive uropathy in children. It results from a functional or anatomical obstruction at the junction between the renal pelvis and the ureter, leading to progressive dilation of the renal pelvis and, without appropriate management, to irreversible impairment of renal function [1]. The prevalence of UPJO is estimated to be between 1/500 and 1/1,500 live births, with a predilection for the left side [2].        In high-income countries, the diagnosis of UPJO relies primarily on prenatal screening by ultrasound, allowing for neonatal monitoring and planned surgical intervention before the onset of functional complications. In sub-Saharan Africa, several studies report, on the contrary, late diagnoses, often revealed by emergency presentations (pain, urinary tract infections, obstructive renal failure), linked to limited access to imaging, the absence of structured prenatal care, and major socioeconomic constraints [3-4].

In Gabon, specific data concerning PUJS remain limited. The main objective of this study was to describe the epidemiological, clinical, therapeutic, and short-term outcome characteristics of children treated for PUJS in the pediatric surgery department of the CHUME FJE.      

Study Area and Site

The study took place in Libreville, the political and administrative capital of Gabon, the country's largest city in terms of population, and the capital of the Estuary Province. Its population is estimated at 846,090 in 2025, representing nearly half of the country's population [4]. Patients were recruited from the Jeanne-Ebori Foundation Mother-Child University Hospital (CHUME FJE). This hospital is organized into two departments: a mother department and a child department. The child department comprises a pediatrics ward, a pediatric surgery department, a neonatal medicine department, a pediatric emergency department, a diagnostic department (radiology), an outpatient department (ophthalmology, stomatology), and a pharmacy. This department has four general pediatric surgeons.

Study Design and Study Population

This was a retrospective descriptive study, conducted from January 2019 to October 2022, which systematically included all children hospitalized for SJPU at the CHUME FJE during the study period.

Study Procedure

Data were collected using individual patient questionnaires. On these questionnaires, we grouped the measured variables into different categories: patient and parental identity, personal and family history, clinical aspects, paraclinical aspects, and finally, therapeutic and outcome aspects.

Statistical Considerations

Data were collected using a standardized individual data collection form and digitized using Microsoft Excel. The final database was exported to R version 3.2.4 for statistical analysis. Quantitative variables were summarized using the mean and standard deviation (SD). Proportions were used to summarize qualitative data.

Sociodemographic Characteristics

Eight children with SJPU were included. The mean age was 3.2±2.8 years. The age distribution showed a homogeneous distribution between children under 2 years of age and those aged 2 to 11 years (Table 1). There was a male predominance with a sex ratio of 7 (Table 1).

Table 1:  Sociodemographic Characteristics of the 8 Children with Pyoloureteral Junction Syndrom

Clinical presentation

Clinically and paraclinically, hydronephrosis was found in 7 children, while one case presented with ureterohydronephrosis (Table 2).

Table 2 : Clinical Signs Present on Examination in the 8 Patients of the Study

Therapeutic Management

All patients (8/8) underwent surgical treatment. The procedure performed was systematically a pyeloplasty. The average time to treatment was 0.9±0.4 days.

Outcome

The postoperative course was favorable in all patients (8/8).

The objective of this study was to describe the epidemiological, clinical, therapeutic, and short-term outcome characteristics of children treated for ureteropelvic junction obstruction (UPJO) in the pediatric surgery department of the University Hospital of the FJE (Fribourg University Hospital). It highlights that UPJO constitutes, in our setting, a significant cause of pediatric urological emergencies requiring rapid surgical intervention.        The observed male predominance is consistent with data from the literature, where males are classically more affected, with a sex ratio varying between 2 and 3 depending on the series [1-2]. The relatively young average age of our patients reflects the congenital nature of the condition, but also suggests a late postnatal diagnosis compared to countries with systematic prenatal screening. In this regard, Nouira et al. [5] reported the management of 53 patients with a ureteropelvic junction obstruction diagnosed prenatally. The clinical presentation dominated by hydronephrosis is consistent with data reported in African and international series, where PUJS is often diagnosed at an already advanced stage, sometimes during painful or infectious episodes [3, 6]. The systematic use of pyeloplasty in this series reflects both the recognized efficacy of this technique as the standard treatment for pelvic junction obstruction (PJO) and the limitations of minimally invasive alternatives in our setting. In several African countries, open surgery remains the most accessible modality due to a lack of equipment and specialized training for laparoscopic surgery [4, 6, 7]. The average time to treatment of less than one day reflects the responsiveness of healthcare professionals to these obstructive emergencies. The main limitations of this study lie in its retrospective nature and the very small sample size, leading to a lack of statistical power and information bias. Despite this, this series provides an overview of a pathology that remains poorly documented in our context.

Ureteropelvic junction obstruction (UPJO) represents a significant pediatric urological emergency in our setting. It predominantly affects boys and primarily manifests as hydronephrosis requiring prompt surgical intervention. Pyeloplasty allows for a favorable short-term outcome when performed without delay. Strengthening early detection and implementing multicenter studies with long-term functional follow-up are priority areas for improvement.

1. Koff, S.A. “Pathophysiology and management of ureteropelvic junction obstruction in children.” J Urol. 2020.

2. Szymanski, K.M. and Whittam, B.M. “Contemporary management of ureteropelvic junction obstruction in children.” Pediatr Nephrol. 2021.

3. Ndoye, N.A. et al. “Les urgences urologiques en chirurgie pédiatrique : à propos de 40 cas.” Mali Med. vol. 30, no. 2, 2015, pp. 33–35.

4. Sangaré, D. et al. “Place de l’urologie pédiatrique dans le paquet d’activité chirurgicale en Afrique subsaharienne.” J Chir Spéc Mali. vol. 1, no. 1, 2021, pp. 28–35.

5. Nouira, F. et al. “Anomalie de la jonction pyélo-urétérale de diagnostic anténatal : traitement chirurgical ou médical ?” J Pédiatr Puéricult. vol. 24, 2011, pp. 229–235.

6. Salihou, A.S. et al. “Notre expérience de la pyéloplastie selon Küss Anderson Hynes dans le syndrome de la jonction pyélo-urétérale de l’enfant à l’Hôpital Gynéco-obstétrique et pédiatrique de Yaoundé (HGOPY) : à propos de 13 cas.” RECAC. vol. 4, no. 27, 2024, pp. 53–58.

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