<s>[INST] I have Just born baby ( 2 days), He went for Abdomen & KUB scan! the result of scan: IMPRESSION DILATED CALYCEAL SYSTEM IN LEFT KIDNEY LIVER, GB, SPLEEN, PANCREAS, RIGHT KIDNEY & BLADDER APPEAL NORMAL, My question is? How my baby get normal kidney function on left kidney? [/INST] Hi...an ultrasound scan doesn't tell you about the function of the kidney. You need a DMS scan for this. A 2 days baby having a dilated pelvicalyceal system means that it is an antenatal HY Chat Doctor.  Many of these get better by themselves. If I were your pediatrician all I would do is a renal function testing in the blood and if it is normal I would do follow ultrasound scans once in 3 months to see if it's getting better by itself. Regards -  </s>