The records of 180 myelodysplasia patients followed from 3 to 18 years were reviewed. Studies included cystography to evaluate vesicoureteral reflux and dimercapto-succinic acid renal scintigraphy to identify acute inflammation and renal scarring. Scarring was noted in 28 of 180 patients (15.5%), of whom 68% were girls. Of the patients with renal scarring 75% had associated reflux and 40% over-all were identified as having reflux. Management of patients with vesicoureteral reflux included clean intermittent catheterization, antibiotic prophylaxis and anticholinergics when indicated. Only 17 of 72 patients (24%) had ureteral reimplantation. Surgical indications included persistent high grade reflux and/or progressive upper tract damage. Reflux resolved in 62% of those on medical management. Resolution was not dependent on grade of reflux (as compared to primary reflux). Twenty-one patients are stable and being followed with persistent reflux. In 7 patients new renal scars developed during aggressive medical management, 5 of whom underwent subsequent surgical correction.