To the Editor. A total of 227 children (142 females and 85 males), age range 15 days to 4 years (95% <2 years), admitted to nine pediatric departments were enrolled in a prospective study at their first episode of acute pyelonephritis (AP), to assess if different clinical presentations in children with or without vesicoureteral reflux (VUR) might be used as discriminating criteria as to whether or not to perform micturating cystourethrography (MCUG).A questionnaire concerning modalities of fever development and other symptoms was completed: particular attention was addressed to the presence or absence of other symptoms or signs (ie, low fever, anorexia, irritability or drowsiness, diarrhea, foul-smelling urine) preceding onset of high fever; a MCUG was performed 4 to 8 weeks later and revealed a VUR in 92 (40.5%) children. At least one of the symptoms, mentioned above, was present in the clinical history of 114 out of 218 children with fever >38.5°C; of these, only 16 children later revealed VUR; on the contrary, 85 of the 104 children without symptoms preceding fever revealed VUR (P < .0001). Nine children presented different symptoms suggestive of urinary tract infection (UTI) (failure to thrive, weight loss, significant anorexia, low fever, jaundice, diarrhea). VUR was found in 5 out of 9 (4 were <6 months).If MCUG had been performed only in children without any other symptom before fever onset (104 out of 218 febrile children), VUR would have been detected in 85 out of 101 cases (84.1%) with 16 patients missing diagnosis (most of these undiagnosed VURs were low grade). The reduction in MCUGs performed would have been considerable (114 instead of 218). Greater sensitivity could be also obtained by performing MCUG in all children <4 months (only 9 undiagnosed VUR). Our findings suggest, if confirmed by further data, the following strong indications for MCUG (in patients <4 years) at the first episode of UTI: 1) all children asymptomatic before high fever onset (without low fever, anorexia, irritability or frequent crying, diarrhea, and drowsiness); 2) all infants <4 months; 3) all children with persistent ultrasound and/or radioisotopic abnormalities after acute phase of UTI; 4) all children with a family history of VUR. Our strategy seems to improve the cost-benefit relationship in children with UTI by significantly reducing the need for invasive and expensive radiological procedures.1,2