Bladder/bowel dysfunction in pre-school children following febrile urinary tract infection in infancy

BACKGROUND: An association between bladder-bowel dysfunction (BBD) and urinary tract infection (UTI) is well-known. However, a question less explored is whether children with UTI early in life also have increased prevalence of BBD after they are toilet-trained. In this study, consecutively selected children with pyelonephritis during their first year of life were assessed for BBD at pre-school age. METHODS: Ninety-two children (51 boys) hospitalized due to pyelonephritis during their first year of life were assessed for BBD at median age 5.4 years. A validated BBD questionnaire, along with urine flow and residual volume measurements, was used for diagnosing BBD. During follow-up, the group was well-characterized regarding renal status, vesicoureteral reflux (VUR), and recurrent UTI. RESULTS: BBD was diagnosed in 35/92 (38%), of which the majority was sub-diagnosed with dysfunctional voiding (DV). There was a strong association between BBD and recurrent UTI during follow-up (p < 0.0001), but only a slight association with VUR status at presentation. Nevertheless, in the group with both BBD and VUR, recurrent UTI was four times higher (12/13, 92%) than in children who had neither VUR nor BBD (23%), (p = 0.0008). BBD was also associated with kidney damage (p = 0.017). CONCLUSION: In children with pyelonephritis during the first year of life, 38% had BBD at pre-school age, regardless of whether they had VUR or not. The study shows an important association between BBD and recurrent UTI, so an assessment of BBD is therefore recommended for pre-school children with UTI, especially when they have history of pyelonephritis during infancy. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00467-020-04853-4.