UROLOGICAL SURVEY
NEUROLOGY & FEMALE UROLOGY
Correlations between pretransplant dialysis duration, bladder capacity, and prevalence of vesicoureteral reflux to the graft
Inoue T; Satoh S; Saito M; Numakura K; Tsuruta H; Obara T; Narita S; Horikawa Y; Tsuchiya N; Habuchi T
Department of Urology, Akita University School of Medicine, Akita, Japan. 2 Division of Renal Replacement Therapeutic Science, Akita University School of Medicine, Akita, Japan
Transplantation. 2011; 92: 311-5
BACKGROUND: Urinary bladder capacity is reduced in patients undergoing long-term dialysis, which may increase the risk of vesicoureteral reflux (VUR) to a transplanted kidney. This study investigated the correlations between dialysis duration, pretransplant and posttransplant bladder capacity, and prevalence of VUR to the graft.
METHODS: Voiding cystography was performed in 101 adult renal transplant recipients without neurogenic disorders immediately before and 1 year after transplantation to evaluate bladder capacity and VUR. Nonstented extravesical antireflux ureteroneocystostomy was performed in all patients.
RESULTS: The median dialysis duration and pretransplant bladder capacity were 32 months (range 1-426 months) and 120 mL (range 15-450 mL), and 21 patients (20.8%) underwent dialysis for more than 120 months, and 30 patients (29.7%) had a pretransplant bladder capacity of less than 80 mL. Dialysis duration was correlated with pretransplant bladder capacity (R = 0.466, P < 0.001). Bladder capacity expanded more than 6-fold from pretransplantation to posttransplantation, and all recipients had a bladder capacity greater than 150 mL at 1 year posttransplantation. Thirty patients had VUR to the graft. Dialysis duration longer than 60 months (P = 0.021) and pretransplant bladder capacity of less than 130 mL (P = 0.024) were associated with VUR. VUR was associated with lower graft function.
CONCLUSIONS: Although bladder capacity decreased because of long-term dialysis, it exceeded 150 mL at 1 year posttransplantation. A small bladder can be used in renal transplantation, but it may increase the risk of VUR.
Editorial Comment
This paper by Inoue et al. is of special interest for those who attend kidney transplant patients. It provides valuable information on the outstanding recovery capacity of defunctionalized bladders, which may have a pretransplant volume as low as < 50 mL but can potentially achieve a more than 6-fold increase at 1 year posttransplantation. All patients ended up with a > 150 mL bladder capacity following transplantation.
On the other hand, patients with low bladder capacities, notably those below 80 mL, and dyalisis lasting longer than 60 months were shown to be at higher risk of developing post operative high grade vesicoureteral reflux (VUR).
Although not a consensus in medical literature, this study showed an association of VUR and decreased renal graft function at one year follow-up.
These data should raise some important thoughts: the need to speed up renal transplantation in an effort to avoid a longer than 60 months period of dyalisis; a higher suspicion for VUR in patients who present a very low (< 80 mL) bladder capacity before transplant; and finally, we should rethink the need to routinely perform urodynamics in the preoperative planning of kidney transplant candidates, as it may provide valuable prognostic data.
Dr. Ricardo Miyaoka
State University Campinas
Campinas, SP, Brazil
E-mail: rmiyaoka@uol.com.br
Publication Dates
-
Publication in this collection
19 Oct 2011 -
Date of issue
Aug 2011
