['The aim of this study was to evaluate whether renal scars and vesicoureteral reflux (VUR) are associated with bladder dysfunction in children after first clinical pyelonephritis.', 'Sixty-four children were evaluated with urodynamics and voiding cystourethrography at a median of 8 weeks after their first episode of clinical pyelonephritis. All patients had ultrasonography and dimercaptosuccinic acid (DMSA) scintigraphy during the infection. After 2 years, DMSA scintigraphy was repeated in 58 patients. Re-infections were recorded.', 'Overactive detrusor was found in 27 (42%) patients. There was no significant difference in the incidence of overactive detrusor between boys and girls. The maximal voiding pressure was higher in boys (median 92.5, range 48-191 cmH(2)O) than in girls (median 82, range 37-150 cmH(2)O) (P=0.0117). Thirty-one (48%) patients had renal defects in scintigraphy during the infection. Ultimately, 12 patients (21%) developed renal scars; 11 patients (17%) had VUR. Renal defects in DMSA scintigraphy and the presence of VUR were not associated with overactive detrusor or high voiding pressures.'] Are post-pyelonephritic renal scars associated with high voiding pressures?