A 10 month old girl presented with increased frequency of micturation, crying on passing urine and vomiting for 3 days. There is no fever, oliguria or refusal of feeds. On examination, there is no significant abnormality. A urine test revealed 150 pus cells/hpf. Ultrasound (USG) kidneys showed right kidney of 7.2 x 3.4 cm and left kidney of 6.8 x 3.8 cm. There were no dilated ureters, significant post void residue or any renal scars. Urine culture grew E.coli 100000 colony count.