ESPU Meeting on Wednesday 17, June 2026, 15:10 - 16:00
15:10 - 15:14
S02-1 (BSP)
Sachit ANAND 1, Om Prakash SHETE 2, Tarini Shankar GHOSH 2, Ajay VERMA 1 and Kalpana LUTHRA 3
1) All India Institute of Medical Sciences, Department of Pediatric Surgery, New Delhi, INDIA - 2) Indraprastha Institute of Information Technology Delhi, Department of Computational Biology, New Delhi, INDIA - 3) All India Institute of Medical Sciences, Department of Biochemistry, New Delhi, INDIA
PURPOSE
Urinary tract infections (UTIs) are common in children with congenital anomalies of the kidney and urinary tract (CAKUT). We profiled the pre-infection urinary microbiome in Indian children with CAKUT to determine whether microbiome alterations, metabolic shifts and resistome enrichment precede UTI.
MATERIAL AND METHODS
In this cross-sectional study, we collected urine samples from 80 children: 36 with newly diagnosed CAKUT (18 UPJO, 12 VUR, 6 PUV) and 44 controls. Cases were stratified a priori into low (n = 19) and high-risk (n = 17) groups as per a predefined criterion. V3-V4 16S rRNA sequencing was performed for microbiome profiling. Alpha- and beta-diversity were compared using Shannon index and PERMANOVA respectively. Sliding-window and network-based analyses mapped dysbiosis gradients. Metabolic functions were inferred from taxonomic data. Antibiotic resistance patterns were characterized using CARD-RGI and WHO-AWaRe classifications. A p-value of <0.05 was considered as statistically significant.
RESULTS
Shannon-diversity declined significantly from controls to low- and high-risk groups (P = 0.002), with a corresponding increase in intra-group variability (P ≤ 0.005). PERMANOVA revealed distinct clustering by risk (R² = 0.11; P = 0.001). Dysbiosis scores inversely correlated with the first Kendall PCoA axis (ρ = -0.62; P < 0.001). With increasing risk of UTI, the control-associated genera declined along this axis while the facultative pathogens became dominant. Control microbiomes were enriched for short-/branched-chain fatty-acid and spermidine biosynthesis; high-risk microbiomes over-produced ammonia, putrescine, and cadaverine. Resistance to 18/22 routinely tested antibiotics was almost confined to the 31 risk-associated microbiomes (P = 0.001).
CONCLUSIONS
Loss of health-associated genera within the urinary microbiome, coupled with metabolic imbalance and broad-spectrum antibiotic resistance, is observed in CAKUT children even before their first symptomatic UTI.
15:14 - 15:18
S02-2 (BSP)
Sugandha AGARWAL 1, Himalaya KUMAR 1, Ajay VERMA 1, Vineet AHUJA 2 and Sachit ANAND 1
1) ALL INDIA INSTITUTE OF MEDICAL SCIENCES DELHI, PAEDIATRIC SURGERY, Delhi, INDIA - 2) ALL INDIA INSTITUTE OF MEDICAL SCIENCES DELHI, DEPARTMENT OF GASTROENTEROLOGY, Delhi, INDIA
PURPOSE
Children with neurogenic bladder (NB) are prone to recurrent urinary tract infections, antibiotic-resistant uropathogen colonization and kidney damage. Given limited data on urinary microbiome in pediatric NB, we compared urobiome profiles between NB vs. healthy children and assessed differences among patient groups divided by kidney-damage status.
MATERIAL AND METHODS
In this cross-sectional study, urine samples were collected from 39 children with NB and 44 matched controls. NB patients were divided into group A (kidney damage: GFR <60 mL/min/1.73 m² BSA and/or renal scarring) and group B (no kidney damage). V3-V4 16S rRNA sequencing was performed: alpha diversity (Shannon and Simpson), beta diversity (Bray-Curtis and Jaccard) and taxonomic profiles (family/genus) were analyzed. Functional potential was inferred using PICRUSt2, and antibiotic resistance patterns were characterized using CARD-RGI. The diversity metrics, taxonomic profiles, inferred metabolic functions and antibiotic resistance patterns were compared between NB vs. controls and among two patient groups. A p value of ≤0.05 was considered statistically significant.
RESULTS
Alpha diversity differed significantly between NB vs. controls (Shannon p=0.004, Simpson p=0.003), and beta diversity also varied significantly (p<0.05). Between two NB groups, alpha diversity was not significantly different (Shannon p=0.7; Simpson p=0.06), whereas beta diversity differed significantly (p=0.001). Family-level profiles showed enrichment of Enterobacteriaceae and Enterococcaceae in NB vs. Veillonellaceae and Propionibacteriaceae in controls. Differentially abundant genera included Escherichia-Shigella, Enterococcus and Acinetobacter in NB, vs. Lactobacillus, Veillonella, Propionimicrobium, and Varibaculum in controls; differences were significant at both family and genus levels. Taxonomic profiles were also significantly different between NB groups at family and genus levels. Functional inference suggested predominance of amino-acid degradation and neurodegeneration-associated kynurenine pathways in NB vs. controls; group A additionally showed predominance of anthranilate-CoA–related features and TetR/AcrR family signatures. Broad-spectrum antibiotic resistance was confined to NB samples with control microbiomes showing resistance limited to penicillin and quinolones. Resistance patterns did not differ between two NB groups.
CONCLUSIONS
When compared with healthy controls, pediatric NB is associated with a distinct urinary dysbiosis enriched with pathobionts with predictive metabolic remodelling and broader resistome signatures. NB group associated with kidney damage is linked to significant compositional shifts despite similar alpha diversity, supporting urobiome-based risk stratification and antimicrobial stewardship.
15:24 - 15:28
S02-3 (BSP)
Filipa M. LOPES, Adrian S. WOOLF and Neil A. ROBERTS
The University of Manchester, School of Biological Sciences,, Manchester, UNITED KINGDOM
PURPOSE
Rare early-onset lower urinary tract (REOLUT) disorders are individually uncommon but collectively they are the main cause of severe kidney failure in children and young adults. Some such diseases, such as urofacial and prune belly-like syndromes, feature functional bladder outflow obstruction, and they can have defined monogenic causes. These include mutations of genes (e.g. CHRM3, CHRNA3, HPSE2, and MYOCD) involved in functional differentiation of urinary bladder smooth muscle (SM) and its autonomic innervation. Moreover, the Hpse2 mutant mouse is a model of urofacial syndrome and non-neurogenic neurogenic bladder, and its bladder dyssynergia has been ameliorated using adeno-associated viral (AAV) vector/HPSE2 therapy which targets pelvic ganglia in vivo.
MATERIAL AND METHODS
To begin to translate these genetic insights and technical advances towards human gene therapy, we established a preclinical in vitro model in which human neural cells and bladder SM cells were targeted with AAVs.
RESULTS
By using a range of AAV vectors, specific subtypes were found to efficiently transduce either human neural and/or bladder SM cells in culture, as assessed by expression of a green fluorescent protein reporter gene. Moreover, we developed a co-culture system in which differentiated human neural cells expressed CHRNA3, a pelvic ganglion nicotinic receptor, and extended neurites to engage human bladder SM cells which themselves expressed CHRM3, the major detrusor muscarinic receptor, and MYOCD, a transcription factor-associated protein required for SM differentiation. Finally, we used a AAV vector to transduce human HPSE2 into human neural cells. Bulk RNA sequencing confirmed this was associated with robust expression of this urofacial syndrome gene, together with increased expression of neuron navigator 2, a gene implicated in neuronal differentiation
CONCLUSIONS
This in vitro system will serve as a testbed for gene therapies for REOLUT diseases with a neuro-muscular pathobiology.
15:28 - 15:32
S02-4 (BSP)
Benjamin W JARVIS, Sara AL MAHDY, Marina GHIRADELLO, Ania KRAKOWSKI, Josh GODWIN-AGOH, Filipa M LOPES, Adrian S WOOLF and Neil A ROBERTS
The University of Manchester, School of Biological Sciences, Manchester, UNITED KINGDOM
PURPOSE
The genetic basis to many rare early onset lower urinary tract conditions has been identified, raising the possibility of gene therapies. Urofacial syndrome is an autosomal recessive condition caused by pathogenic variants in HPSE2 (codes for heparanase 2). Patients have dyssynergia between the bladder body and outflow, leading to recurrent UTIs and urine reflux to the kidney. Investigation of Hpse2 knockout mice identified defects in patterning and function of the pelvic autonomic neurons that control bladder voiding. Remarkably, intravenous injection of adeno-associated viral vector (AAV9) to deliver wildtype copies of the human HPSE2 to newborn mice ameliorated these neuromuscular defects. However, newborn mice are equivalent to mid-gestation human fetus, making clinical translation challenging. Our aim was to determine if HPSE2 gene therapy is possible after the neonatal period.
MATERIAL AND METHODS
Intraperitoneal (IP) injection of the AAV9-HPSE2 vector to neonatal and day 4 pups; analysis of bladder neuromuscular function by ex vivo tissue physiology on a myograph platform; BaseScope in situ hybridization for vector transduction on tissue sections.
RESULTS
AAV9-HPSE2 vector delivery by IP injection successfully transduced pelvic autonomic neurons, with vector and human HPSE2 transcripts detected by BaseScope. Bladder neuromuscular function was analysed in the third postnatal week. In wildtype bladders, electrical field stimulation (EFS) activates parasympathetic neurons and elicits frequency dependent smooth muscle contractions; Hpse2 mutant bladders showed a reduction in EFS-induced contractions of ~ 50 % (p=0.019). Conversely, response to the muscarinic receptor agonist carbachol is higher in mutants (p=0.008). Bladders from male Hpse2 mutant mice treated neonatally and on postnatal day 4 showed EFS-induced contraction statistically similar to the WT at all frequencies, indicating rescue of the neurogenic defect. However, the increased response to carbochol was not ameliorated.
CONCLUSIONS
Our results demonstrate that the therapeutic window for treating male Hpse2 mutant mice extends beyond the neonatal period. This brings us closer to the equivalent six months of postnatal life in human, a key age for clinical translation when diagnosis, genetic testing and therapeutic intervention is feasible. Our next preclinical steps are to define the limit of the neurogenic therapeutic window and target the myogenic defect.
15:38 - 15:42
S02-5 (BSP)
Julia KOIVULA 1, Niklas Alarik PAKKASJÄRVI 2 and Satu KUURE 1
1) University of Helsinki, Helsinki Institute of Life Science (HiLIFE) ja STEMM, Integrative Developmental Biology, Helsinki, FINLAND - 2) New Children's Hospital Helsinki University, Department of Pediatric Surgery, Section of Urology, Helsinki, FINLAND
PURPOSE
The spiny mouse (Acomys) is an emerging model for kidney development, displaying human-like nephrogenesis. Unlike humans, Acomys retains the capacity for functional tissue regeneration without fibrosis or reported tumor formation. To understand these unique properties, we investigate (1) pathways governing the transition of nephron progenitors to terminal differentiation and (2) Acomys resistance to oncogenic transformation. Clarifying this balance between regeneration and tumor suppression may reveal mechanisms relevant to Wilms tumor and other pediatric renal malignancies.
MATERIAL AND METHODS
Developing and postnatal Acomys kidneys (E29 and P7) underwent single-nucleus RNA/ATAC sequencing to profile nephron progenitors and assess chromatin accessibility across developmental stages.
Embryonic fibroblasts were genetically modified using CRISPR/Cas9 to generate:
1. a Tp53-inactivated line, and
2. a Tp53 + let-7-inactivated line (modeling LIN28/let-7 dysregulation implicated in Wilms tumor).
Cells were characterized in vitro for proliferation and survival. Tumorigenic behavior was assessed in vivo by subcutaneous injection into immunodeficient mice and xenotransplantation into zebrafish embryos.
RESULTS
Sequencing demonstrated that nephron progenitors (EYA1/BMPER-positive) were present at E29 but absent at P7, confirming complete terminal differentiation before birth, a pattern more similar to human than house mouse kidney development. Accessibility profiles highlighted distinct regulatory transitions associated with progenitor shutdown.
Tp53-inactivated fibroblasts showed a clear proliferative advantage in vitro but did not form tumors in mice and showed no invasive behavior in zebrafish embryos, indicating intact endogenous tumor-protective mechanisms.
Combined Tp53 + let-7 suppression produced stronger proliferative phenotypes, and xenotransplanted cells survived as dispersed clusters in zebrafish embryos. Although no solid tumors have been observed to date, these findings suggest early oncogenic activation when both pathways are disrupted.
CONCLUSIONS
Acomys demonstrates a human-like pattern of nephron progenitor differentiation and strong resistance to malignant transformation, even after canonical p53 loss. Partial loss of resistance following let-7 suppression indicates robust intrinsic tumor-protective mechanisms. Understanding how Acomys balances regeneration with tumor suppression may uncover protective pathways absent or dysfunctional in Wilms tumor, offering new directions for molecular risk stratification and safer nephron-sparing strategies.
15:42 - 15:46
S02-6 (BSP)
Marcela AMBROGI 1, Laura HERNANDEZ 2, Kimberly K STIETZ 3, Tamryn JORDAN 3, Jennika L FINUP 1, Vinaya BHATIA 1, Kristin EBERT 1, Shannon CANNON 1, Chad VEZINA 3 and Walid FARHAT 1
1) UW Madison, Urology, Madison, USA - 2) UW Madison, Dairy Science, Madison, USA - 3) UW Madison, Comparative Biosciences, Madison, USA
PURPOSE
Bladder and bowel dysfunction (BBD) affects up to 40% of pediatric urology patients. Presentations include overactive or underactive bladder and lower urinary tract symptoms (LUTS), often accompanied by constipation, encopresis, and recurrent urinary tract infections. BBD frequently co-occurs with behavioral and neuropsychiatric disorders, contributing to poorer outcomes. Serotonin (5-HT), largely produced in the gut and regulated by the serotonin transporter (SERT), plays key roles in urinary function, gastrointestinal motility and neuropsychiatric regulation. However, the connection between BBD, 5-HT signaling, and SERT has not been investigated. This study investigates how deletion of SERT influences urinary and bowel function, as well as behavior, using Sert knockout (-/-) mice.
MATERIAL AND METHODS
Urinary function was evaluated in male Sert -/-, Sert heterozygous (+/-), and wild type (WT) mice (n = 4-8/group, 6-7 weeks of age) using uroflowmetry and voiding spot assay (VSA). For uroflowmetry, mice were placed in chambers for 4 hours with access to water only. Uroflow data were collected using cameras to capture urination and defecation. For the VSA, mice were placed individually in cages containing chromatography paper for 4 hours with access to food only. To assess anxiety-like behavior, mice underwent open field and elevated plus maze testing. Statistical analysis was performed using one-way ANOVA.
RESULTS
Male Sert -/- mice had the lowest urinary (p = 0.016), and fecal pellet (p = 0.038) frequencies and the longest intervoid intervals (p = 0.018) compared with WT and Sert +/- mice. Total void counts in the VSA were not different between groups (p = 0.46). Sert -/- mice showed increased time in the periphery of the open field (p = 0.001), increased immobility (p = 0.001), and more time in closed arms of the elevated plus maze (p = 0.005), indicating heightened anxiety like behavior.
CONCLUSIONS
Male Sert -/- mice display features consistent with bladder and bowel dysfunction: reduced urinary frequency (suggestive underactive bladder), diminished stool output, extended dry intervals and anxiety like behavioral. These findings suggest serotonergic pathways regulates bladder bowel and neuropsychiatric function. Future studies will incorporate female mice and additional physiological validation.