Understanding and Addressing Vesicoureteral Reflux in Pediatric Patients: A Comprehensive Exploration of Diagnostic Strategies, Challenges, and Optimized Management Approaches

ABSTRACT


INTRODUCTION
Primary vesicoureteral reflux is one of the most common congenital abnormalities of the urinary tract in pediatric patients, which is characterized by a retrograde flow of urine from the bladder to the kidneys.This pathology affects between 0.4% and 2% of the general population, being discovered mainly during evaluations due to recurrent urinary tract infections, however, the prevalence of primary vesicoureteral reflux in children with urinary tract infection varies depending on the differences between patients.Up to 10%-51.4% of primary vesicoureteral reflux has been identified in children investigated for recurrent urinary tract infection.According to studies, when vesicoureteral reflux coexists with bladder and bowel dysfunction, there is an increased risk of recurrent urinary tract infections leading to long-term sequelae such as renal scarring, hypertension and adrenal insufficiency.It is observed that black children have a lower prevalence of vesicoureteral reflux compared to white children, being of greater severity in this type of patients, in turn, It has also been identified that at the time of diagnosis about 30%-54% of children with vesicoureteral reflux have renal parenchymal disease with the presence of scarring, among the most important risk factors for the development of renal scarring in children are the presence of high-grade vesicoureteral reflux and recurrent pyelonephritis.
In terms of gender, it has been identified that boys tend to present with vesicoureteral reflux prenatally or during the first year of life and often present in a severe and bilateral manner, while girls tend to be diagnosed at a later age compared to boys, and their presentation tends to be less severe and more prone to recurrent urinary tract infections. [1-2]

EPIDEMIOLOGY
The reported prevalence of the presence of vesicoureteral reflux varies according to various literatures from 1-2% of apparently healthy children at birth and increases from 8-50% in children who are evaluated after a urinary tract infection, since the diagnosis of vesicoureteral reflux in newborns and infants secondary to a urinary tract infection is 36-49%, with male patients being diagnosed in a more timely manner, while female patients are diagnosed later.Most male patients are diagnosed prenatally when secondary to investigation of hydronephrosis, whereas female patients are mostly diagnosed because of recurrent urinary tract infections.[3]

CLASSIFICATION OF VESICOURETERAL REFLUX
The gold standard for the diagnosis of vesicoureteral reflux is the performance of excretory cystourethrography, this study helps the classification of this pathology in 5 grades, according to some studies the grade that most commonly occurs in patients is grade 1, usually this grade 1 improves over time and this is attributed to the elongation of the submucosal segment of the ureter with the general growth of the body.In a study in which several patients with vesicoureteral reflux were followed up, it was reported that the time to resolution of this pathology was approximately 38 months for grade I/II, 98 months for grade III, and 156 months for grade IV/V.[3][4] Bladder dysfunction secondary to vesicoureteral reflux.Bladder dysfunction associated with vesicoureteral reflux has been reported in both children and adults, with 25-68% of patients with vesicoureteral reflux having bladder dysfunction, the most common being detrusor overactivity and sphincter overactivity, both associated with a significant increase in bladder pressure.[3][4]

Urinary tract infection secondary to vesicoureteral reflux.
There are several mechanisms by which the urinary tract protects itself to prevent the invasion of microorganisms harmful to the urinary system, among which are the complete emptying of the bladder, the secretion of proteins and antimicrobial peptides in the urinary stream and the unidirectional flow of urine, where the latter is one of the mechanisms that favor the presence of urinary tract infection secondary to vesicoureteral reflux.[5][6] Among the main infectious agents that are associated with urinary tract infections is Escherichia coli being the most implicated and the most studied, other associated bacteria are gram negative bacteria, including Klensiella, Pseudomonas, Proteus, Enterobacter, among other pathogens.The manner of infection of bacteria in the urinary tract usually triggers an innate immune response in the host involving inflammatory cytokine production, complement activation, antimicrobial peptide secretion and phagocyte recruitment, and although the immunity effectively eradicates the bacteria, the resulting inflammation also causes clinical symptoms of cystitis.When patients present acute pyelonephritis is when the presence of vesicoureteral reflux should be considered due to the failure of the unidirectional flow mechanism, causing and favoring bacterial growth in the renal parenchyma, which triggers the symptoms of acute pyelonephritis, among the most prominent, being fever, therefore it is essential to search for vesicoureteral reflux in pediatric patients who present acute pyelonephritis.[6-7]

DIAGNOSTIC
For the diagnosis of vesicoureteral reflux, many considerations must be taken into account, not only the performance of imaging studies, since as mentioned above, vesicoureteral reflux can present itself in various ways, among the main suspicions are urinary tract infections, so at the beginning of the medical follow-up of this entity it is recommended to start with the identification of urinary tract infection with clinical and laboratory tests.Among the clinical practice guidelines of the American Academy of Pediatrics, the presence of a positive urine culture and pyuria defines the presence of a urinary tract infection.To define pyuria, it should be identified by urinalysis, with the presence of greater than 10 white blood cells/mm3 or the presence of leukocyte esterase on a dipstick.Among the imaging studies that can be performed, the most common and accessible is the renal ultrasound, which although it serves to diagnose the presence of renal abscess or hydronephrosis, does not rule out the presence of vesicoureteral reflux, studies indicate that only 11% of patients could identify the presence of vesicoureteral reflux, Among the most suggestive ultrasound findings for this pathology is the presence of hydronephrosis or ureteral dilatation and changes in the renal parenchyma, being the best diagnostic study for the detection of vesicoureteral reflux the excretory cystourography, which supports the identification of structural abnormalities such as vesicoureteral reflux and its classification.[2,[7][8]

CONCLUSION
In conclusion, our comprehensive exploration of vesicoureteral reflux (VUR) in pediatric patients underscores the intricate nature of this urological condition.The diversity Corresponding Author: Mildred Andrea Zúñiga Onofre of diagnostic strategies available, from traditional voiding cystourethrography to contemporary imaging technologies, offers clinicians a spectrum of tools to evaluate reflux severity and associated complications.However, the challenges inherent in pediatric patients, including agerelated variations and evolving clinical presentations, emphasize the need for a nuanced and individualized approach to diagnosis.Furthermore, the optimized management approaches discussed in this article provide clinicians with a repertoire of interventions tailored to the specific needs of each patient.The consideration of reflux grade, patient age, and concurrent conditions is paramount in crafting effective treatment plans.Surgical and non-surgical modalities, each with its unique advantages and limitations, offer a spectrum of choices for clinicians to navigate.As we strive for enhanced understanding and precision in addressing pediatric VUR, ongoing research and technological advancements will undoubtedly contribute to refining diagnostic accuracy and therapeutic efficacy.The role of antibiotic prophylaxis in preventing urinary tract infections and safeguarding renal function remains pivotal, highlighting the holistic nature of managing VUR in the pediatric population.In embracing the complexities of diagnosis and management, clinicians are empowered to provide tailored and effective care for young patients with VUR, ultimately promoting improved outcomes and quality of life.Continued collaboration between urologists, pediatricians, and researchers will foster a deeper understanding of this condition, paving the way for future advancements in the field.