Age-related renal parenchymal lesions in children with first febrile urinary tract infections.

OBJECTIVE: The aim of this study was to define the association between age and the occurrence of acute pyelonephritis and renal scars. METHODS: Between 1999 and 2002, all children 0 to 14 years of age consecutively seen with a first febrile urinary tract infection were enrolled in the study. (99m)Tc-Dimercaptosuccinic acid renal scintigraphy was performed within 5 days after admission for the detection of renal parenchymal involvement. The presence of vesicoureteral reflux was assessed by using cystography performed 1 month after the infection. If the acute scan results were abnormal, then follow-up (99m)Tc-dimercaptosuccinic acid scanning was performed after 6 months, to assess the frequency of scars. RESULTS: A total of 316 children were enrolled in the study (190 children <1 year, 99 children 1-4 years, and 27 children 5-14 years of age). (99m)Tc-Dimercaptosuccinic acid scintigraphy revealed that 59% of the children had renal involvement in the acute phase of infection. The frequency of kidney involvement in infants <1 year of age (49%) was significantly lower than that in children 1 to 4 years of age (73%) and >5 years of age (81%). Of the 187 children with positive acute (99m)Tc-dimercaptosuccinic acid scan results, 123 underwent repeat scintigraphy after 6 months. Renal scars were found for 28% of children <1 year, 37% of children 1 to 4 years, and 53% of children 5 to 14 years of age. No significant differences in the frequency of scars and the presence or absence of vesicoureteral reflux were noted. CONCLUSIONS: Our findings confirm that acute pyelonephritis and subsequent renal scarring occur only in some children with first febrile urinary tract infections. Children <1 year of age with febrile urinary tract infections have a lower risk of parenchymal localization of infection and renal scarring.

Procalcitonin to reduce the number of unnecessary cystographies in children with a urinary tract infection: a European validation study.

OBJECTIVE: To validate high serum procalcitonin (PCT) as a predictor of vesicoureteral reflux (VUR) in children with a first febrile urinary tract infection (UTI). STUDY DESIGN: This secondary analysis of prospective hospital-based cohort studies included children ages 1 month to 4 years with a first febrile UTI. RESULTS: Of the 398 patients included in 8 centers in 7 European countries, 25% had VUR. The median PCT concentration was significantly higher in children with VUR than in those without: 1.6 versus 0.7 ng/mL (P = 10(-4)). High PCT (> or =0.5 ng/mL) was associated with VUR (OR: 2.3; 95% CI, 1.3 to 3.9; P = 10(-3)). After adjustment for all cofactors, the association remained significant (OR: 2.5; 95% CI, 1.4 to 4.4; P = 10(-3)). The strength of the relation increased with the grade of reflux (P = 10(-5)). The sensitivity of procalcitonin was 75% (95% CI, 66 to 83) for all-grade VUR and 100% (95% CI, 81 to 100) for grade > or =4 VUR, both with 43% specificity (95% CI, 37 to 48). CONCLUSIONS: High PCT is a strong, independent and now validated predictor of VUR that can be used to identify low-risk patients and thus avoid one third of the unnecessary cystourethrographies in children with a first febrile UTI.