Early-Onset Graft Pyelonephritis Is Predictive of Long-Term Outcome of Renal Allografts

Abstract

Urinary tract infection (UTI) is the most common bacterial infection encountered in kidney transplant recipients. Graft pyelonephritis (GPN) is associated with acute kidney injury and renal allograft scarring. However, the influence of GPN on renal allograft outcome in kidney transplant recipients remains controversial. Two hundred sixty-five kidney transplant recipients were evaluated for the impact of earlyonset GPN on renal allograft functions between January 2001 and December 2011. Early-onset GPN was defined as the first GPN episode occurring within 6 months after kidney transplantation. Thirty recipients (11.3%) were diagnosed with early-onset GPN. During the mean follow-up period of 69.1 ± 28.9 months, 56 (21.1%) recipients showed renal allograft outcomes of a > 30% reduction in the estimated glomerular filtration rate (eGFR) over 2 years. The poor outcome was significantly more frequent in the early-onset GPN group (13 patients; 43.3%) than in those without early-onset GPN (43 patients; 18.3%) (P = 0.002). Moreover, the linear mixed model revealed a significant difference in the eGFR decline rate over time between the two groups (P < 0.001). Kaplan-Meier analysis showed that renal allograft event-free survival was significantly lower in the early-onset GPN group (P = 0.006). Multivariate Cox regression analyses revealed that early-onset GPN was independently predictive of poor renal allograft outcomes (hazard ratio, 1.96; 95% confidence interval, 1.02-3.77; P = 0.04). In conclusion, early-onset GPN is independently associated with impaired renal functions in kidney transplant recipients. Thus, early-onset GPN could be a predictor for long-term outcome of renal allografts.

Differential gene expression pattern in biopsies with renal allograft pyelonephritis and allograft rejection

“…Total RNA from the FFPE samples were extracted as described previously and reversed‐transcribed into cDNA using SuperScript VILO cDNA synthesis kit (Invitrogen, Carlsbad, CA, USA) (Supplemental Methods).…”

“…is a known complication in renal transplant recipients, especially in the early post-transplant period. [1][2][3][4] Differentiating between renal allograft APN and acute rejection (AR) based on clinical symptoms alone can be difficult. The classic tetrad of costovertebral angle tenderness, fever, elevated white blood cell count, positive urine culture used to diagnose acute pyelonephritis in the native kidney, is frequently not useful for renal allografts.…”

“…All these factors can complicate diagnosis of APN in renal allografts. APN in renal allografts can potentially affect longterm graft function by causing focal scars and reduction in functional parenchyma; 3,4 therefore, early diagnosis and treatment are important.…”

“…Urinary tract infection complicated by acute pyelonephritis (APN) is a known complication in renal transplant recipients, especially in the early post‐transplant period . Differentiating between renal allograft APN and acute rejection (AR) based on clinical symptoms alone can be difficult.…”

Risk Factors for Lower Urinary Tract Dysfunction and Symptoms After Successful Renal Transplantation

“…We previously showed that some patients who successfully underwent RTX developed nocturnal polyuria and nocturia, which affected their QOL [9]. On the other hand, LUT dysfunction may cause urinary tract infection [8], which could affect survival of renal graft [12][13][14]. Thus, we need to focus on LUT dysfunction and LUT symptoms after successful RTX, because it is currently an important issue to improve the QOL of patients with RTX as well as a survival rate of renal graft.…”