Late results of pyeloplasty for idiopathic hydronephrosis in adults

A series of 91 cases of unilateral obstruction of the pelviureteric junction is reviewed. Primary nephrectomy was performed in 13 cases (14%) because of severe hydronephrosis and renal function less than 10% that of the normal kidney. Pyeloplasty was performed according to Anderson-Hynes in 74 cases and with a Culp-De Weerd flap in four cases. Nephrostomy was performed concomitantly with the pyeloplasty in 14 cases. The parenchymal function was normal before pyeloplasty in 78% of the 78 kidneys, though the drainage function was severely impaired in 76 of the kidneys and moderately impaired in two. Urine cultures were positive before pyeloplasty in two patients, and 13 of the treated kidneys contained calculi. Follow-up examination was performed 5 to 12 years (mean 8.5 years) after pyeloplasty in all 78 patients. Of the 17 kidneys with preoperatively impaired parenchymal function, 12 (71%) showed improvement. The drainage function was improved in 68 (91%) of the 75 studied kidneys. Persistently impaired drainage function after pyeloplasty was found only in kidneys with infection secondary to retrograde passage of a ureteral catheter for treatment of postoperative urinary leakage. Urinary infection occurred in 11 of the 33 cases with such leakage. Retrograde ureteral catheterization thus favoured the occurrence of urinary infection. Its importance as a risk factor for severe infection was shown by the necessity for secondary nephrectomy in three cases. Since nephrostomy tended to reduce the incidence of urinary leakage, and thereby the need for indwelling ureteral catheter, and since nephrostomy as such was not associated with urinary infection, we recommend its use in the management of idiopathic hydronephrosis.