[Should horseshoe kidneys with associated urological abnormalities be controlled?]

Horseshoe kidney (HK) is the most common renal fusion anomaly. Urological anomalies (UA) occurs in 52% of HK. The objective of this paper is to know if it's necessary to follow up for a long time the asymptomatic cases of HK with UA.

We reviewed retrospectively 39 cases of children in whom HK was diagnosed in our hospital during 1990 to 2007. The following features have been taken into account: sex, age at diagnosis, associated anomalies, treatment, postoperative complications, results and time of follow-up.

The mean age at diagnosis was 3 years. 18 patients (46.1%) had associated urological anomalies: 9 hydronephrosis, vesicoureteral reflux 6 and 3 kidney duplication. 10 cases of them (55%) were surgically treated: 6 pyeloplasty, 2 endoscopic reflux, one upper pole heminephrectomy and one ureteroneocystostomy. 3 hydronephrosis and 3 vesicoureteral reflux were managed conservatively. The ureteropelvic junction obstruction (UJO) was caused by a crossing lower-pole vessel in four cases (67%) and two by a high ureteral insertion. Three of this cases of obstruction (50%) were adquired over the time (along 5-7 years from diagnosis of hydronephrosis). There were no complications and the mean time of follow up has been 3.6 years (range: 2-6 years).

We think that all HK associated with UA should be controlled, as above 50% are subsidiaries of surgical correction. The hydronephrosis can be obstructive over the time and it could be necessary to check them for a long time.