The natural history, follow-up and therapeutic approach of hydronephrosis after birth

Aim: To determine the natural history, follow-up and therapeutic approach of antenatally diagnosed UPJ-type hydronephrosis after birth. Material and Methods: A total of 108 patients (159 kidneys) associated with antenatally diagnosed UPJ-type hydronephrosis were prospectively followed and treated by the same surgeon between January 2001 and December 2003 for a period of 29 (8-44) months. Ultrasonography and diuretic renogram were used for the diagnosis and follow-up of these patients. SFU grading system and renal pelvic anterior-posterior (AP) diameters were used to determine the severity of hydronephrosis. Results: Seventy-five were boy and 33 were girl. On the first postnatal ultrasound, renal pelvic AP diameter was <15mm in 126 kidneys (surgery, 0.8%), 16-30 mm in 18 (surgery, 22.2%), and >30mm in 15 kidneys (surgery, 80 %). On the first postnatal ultrasound, the severity of hydronephrosis was SFU ? 2 in 125 kidneys (surgery, 0%), SFU-3 in 13 (surgery, 15.4%), and SFU-4 in 21 kidneys (surgery, 71.4%). A total of 142 kidneys (89%) were treated conservatively, while 17 required surgery. Conclusions: Serial ultrasonographic evaluation is very beneficial in determining the natural history of UPJ-type hydronephrosis. The vast majority of mild hydronephrosis is benign and resolve spontaneously without significant renal deterioration. Therefore, close follow-up and invasive tests are not necessary in such cases. About 1/5th of moderate hydronephrosis may require surgery. Therefore, close follow-up is necessary in these patients. About 3/4th of severe hydronephrosis require surgery. Rapid evaluation, close follow-up and timely prompt management are necessary in such cases.