Late recurrent urinary tract infections may produce renal allograft scarring even in the absence of symptoms or vesicoureteric reflux

Transplantation. 2007 Aug 15;84(3):351-5. doi: 10.1097/


Background: The significance of late urinary tract infections (UTIs) after renal transplantation and their association with scarring and graft dysfunction remains controversial. We sought to define the prevalence of renal scarring in allograft recipients with a history of late recurrent UTIs, to determine whether the presence of vesicoureteric reflux (VUR) confers an increased risk of scarring and to establish whether scarring correlates with graft dysfunction.

Methods: Among 307 renal allograft recipients, we identified 56 (18%) with late recurrent UTIs (> or =3/year). A total of 32 patients had undergone further investigation by both 2,3 dimercapto-succinic acid single-photon emission computed tomography (99mTc-DMSA SPECT) scan and micturating cystourethrogram (MCUG).

Results: Of the 32 patients, 24 (75%) had scars on 99mTc-DMSA SPECT and 15 (47%) had reflux on MCUG. Thirteen of these 15 patients with reflux (87%) had scars, although there was no significant correlation between number of scars and degree of reflux. Eleven of 17 patients (65%) with UTIs but without VUR had scars, as did 12 of 14 (86%) with previous graft pyelonephritis. The pattern of scarring (typically multiple focal cortical defects) suggested infection as the cause. This pattern was not seen in a contemporary cohort with vascular occlusions and was rarely seen in patients with chronic allograft nephropathy. Scarring was not associated with inferior graft survival (median follow-up, 15 years).

Conclusions: In patients with late UTIs, renal scarring is a frequent finding. Scarring may occur even in asymptomatic patients without VUR. The lack of an effect on graft survival may reflect successful intervention with prophylactic antibiotics and surveillance urine cultures. Late recurrent UTIs may be damaging to renal allografts, even in the absence of reflux.

MeSH terms

  • Adult
  • Aged
  • Anti-Bacterial Agents / therapeutic use
  • Cicatrix / etiology*
  • Cicatrix / pathology
  • Female
  • Graft Survival / physiology
  • Humans
  • Kidney / microbiology
  • Kidney / pathology
  • Kidney / physiopathology
  • Kidney Transplantation / adverse effects*
  • Kidney Transplantation / pathology
  • Kidney Transplantation / physiology
  • Male
  • Middle Aged
  • Retrospective Studies
  • Secondary Prevention
  • Urinary Tract Infections / complications*
  • Urinary Tract Infections / etiology
  • Urinary Tract Infections / pathology
  • Vesico-Ureteral Reflux / etiology*
  • Vesico-Ureteral Reflux / pathology
  • Vesico-Ureteral Reflux / physiopathology


  • Anti-Bacterial Agents