Ionizing Radiation Exposure in Children with Vesicoureteral Reflux: Should We Be Alarmed?

Abstract

Objectives Ionizing radiation imaging is commonly used for diagnosis and follow up in children with vesicoureteral reflux (VUR). We aim to measure the effective dose (mSv) in patients with VUR.

Methods We reviewed our electronic database of patients under 8-years-old with VUR. Primary endpoint was to calculate the effective radiation dose (ED). Absolute frequencies and percentages were reported for global qualitative variables. This study conducted a logistic regression model to calculate the odds ratio for radiation exposure. Analysis was performed using STATA version 14.0 (StataCorp LLC, College Station, TX, EEUU).

Results A total of 140 patients were found, 97 were assessed for eligibility. We included 59 patients in the final analysis. Mean age was 20 ± 17.9 months, 66% were females. Most cases of VUR were bilateral (44%) and high grade (93.4%). The lowest number of studies per patient was two, with a minimum radiation of 5.7 mSv. The highest radiation was estimated at 20.7 mSv corresponding to a total of five studies. Logistic regression showed that highest grades of VUR and age of first UTI episode were associated with higher ED (OR, 1.7; 95% CI, 0.87-3.31), (OR 1.02; 95% CI 0.97-1.07) respectively. A mean ED for children with VUR was estimated of 5.5 ± 3 mSv/year.

Conclusion In our study, the children with VUR were exposed to 5.5 mSv/year without counting the natural background radiation, which is alarming, and we believe should raise awareness worldwide in how we are unnecessarily diagnosing indolent VUR cases and following patients.

Resumen

Objetivos La imagenología por radiación ionizante es una herramienta usada frecuentemente para el diagnóstico y seguimiento de pacientes con reflujo vesicoureteral (RVU). El objetivo del presente trabajo es calcular la dosis estimada en milisieverts (mSv) de pacientes con RVU.

Métodos Se realizó una revisión retrospectiva de todos los pacientes menores de 8 años con RVU. El objetivo principal fue calcular la dosis de radiación efectiva recibida por los pacientes con base en los estudios imagenológicos realizados hasta el momento de la revisión de la base de datos. Las frecuencias y porcentajes fueron reportados para las variables cualitativas. Se realizó una regresión logística para calcular la asociación de factores de riesgo con la exposición a radiación. El análisis estadístico fue realizado con el programa STATA versión 14.0 (StataCorp LLC, College Station, TX, EEUU).

Resultados Se identificaron 140 patientes, de los cuales 97 fueron evaluados para coprobar su elegibilidad. En total, 59 pacientes fueron incluidos para el análisis final. La edad promedio de los pacientes fue de 20 ± 1,.9 meses, y 66% eran mujeres. La mayoría de casos fueron bilaterales (44%) y de alto grado (93,4%). El menor número de estudios realizados por paciente fue 2, con una dosis mínima de radiación acumulada de 5,7 mSv. La máxima radiación acumulada fue de 20,7 mSv, correspondiente a un total de 5 estudios. La regresión logística demostró que altos grados de reflujo y la edad a la cual tuvieron la primera infección se asociaban con mayores dosis de radiación efectiva (razón de probabilidades [RP]: 1.7; intervalo de confianza del 95% [IC95%]: 0,87–3,31), (RP: 1,02; IC95%: 0,97–1,07), respectivamente. Estimamos una dosis efectiva de radiación de 5,5 ± 3 mSv/año en nuestra población.

Conclusión Nuestro estudio demuestra que pacientes con reflujo son expuestos a un promedio de 5,5 mSv/año sin contar la radiación de base a la que se exponen todos los humanos anualmente, lo cual resulta alarmante. Esto debe generar introspección al momento de evaluar pacientes con reflujo y evitar efectos a largo y mediano plazos.

Keywords

ionizing radiation - children - vesicoureteral reflux - imaging diagnostic - X-rays

Palabras clave

radiación ionizante - niños - reflujo vesicoureteral - diagnóstico imagenológico - rayos X

Author Contributions

All authors contributed to the study conception and design. Material preparation, data collection, and analysis were performed by Nicolas Fernandez, Luis Villarraga and Julian Chavarriaga. The first draft of the manuscript was written by Nicolas Fernandez, and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Ethical Statement

The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Publication History

Received: 27 August 2020

Accepted: 19 August 2021

Article published online:
21 June 2022

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