[Neonatal ultrasonic screening and follow up of urinary tract malformations]

1881 consecutive healthy newborn babies underwent abdominal ultrasonography on day 4-6. 228 subjects presented an echographic abnormality. Renal abnormalities were diagnosed in 213 newborn. Of those, 134 had dilatative uropathy with a pelvic diameter greater than 5 mm, 73 renal medulla hyperechogenicity, 3 ectopics, 2 unilateral renal agenesis and one horseshoe kidney. Extrarenal findings were present in 15 neonates: 11 with surrenal gland haemorrhage and 4 with hepatic ultrasonographic alterations. Grignon classification was used for evaluation of the dilatative urinary tract abnormalities. In 173 renal pelvis (134 neonates) the anteroposterior diameter was found > 5 mm: 97 were classified as GI (5-10 mm), 45 as GII (10-15 mm), 13 as GIII ( > 15 mm), 11 as GIV (moderate dilatation of the calyces with easily identified residual renal cortex) and 7 as GV (severe dilatation of the calyces with atrophic cortex). The follow-up of 72.3% of these abnormalities showed a spontaneous normalization in 90% of GI, 73% of GII and 58% of GIII. Only one patient with GIII demonstrated progressive dilatation and he underwent corrective surgery. 15 of the 17 newborn with severe uropathy (GIV-GV), had regular follow-up. 8 underwent surgery and 7 showed a progressive spontaneous recovery and in 4 of these cases a complete resolution. The ultrasound follow-up of all cases of renal medulla hyperechogenicity and surrenal gland haemorrhage shows a spontaneous resolution without any clinical or biochemical complication.