| Abstract|| |
The aim of this study was to document vascular complications that occurred following cadaveric and living donor kidney transplants in order to assess the overall incidence of these complications at our center as well as to identify possible risk factors. In a retrospective cohort study, 1500 consecutive renal transplant recipients who received a living or cadaveric donor kidney between December 1988 and July 2006 were evaluated. The study was performed at the Nemazee Hospital, Shiraz, Iran. The assessment of the anatomy and number of renal arteries as well as the incidence of vascular complications was made by color doppler ultrasonography, angiography, and/or surgical exploration. Clinically apparent vascular complications were seen in 8.86% of all study patients (n = 133) with the most frequent being hemorrhage (n = 91; 6.1%) followed by allograft renal artery stenosis (n = 26; 1.7%), renal artery thrombosis (n = 9; 0.6%), and renal vein thrombosis (n = 7; 0.5%). Vascular complications were more frequent in recipients of cadaveric organs than recipients of allografts from living donors (12.5% vs. 7.97%; P= 0.017). The occurrence of vascular complications was significantly more frequent among recipients of renal allografts with multiple arteries when compared with recipients of kidneys with single artery (12.3% vs. 8.2%; P= 0.033). The same was true to venous complications as well (25.4% vs. 8.2%; P< 0.001). Our study shows that vascular complications were more frequent in allografts with multiple renal blood vessels. Also, the complications were much less frequent in recipients of living donor transplants.
Keywords: Renal Transplantation, Renal Artery Stenosis, Renal Vein Thrombosis
|How to cite this article:|
Salehipour M, Salahi H, Jalaeian H, Bahador A, Nikeghbalian S, Barzideh E, Ariafar A, Malek-Hosseini SA. Vascular complications following 1500 consecutive living and cadaveric donor renal transplantations: A single center study. Saudi J Kidney Dis Transpl 2009;20:570-2
|How to cite this URL:|
Salehipour M, Salahi H, Jalaeian H, Bahador A, Nikeghbalian S, Barzideh E, Ariafar A, Malek-Hosseini SA. Vascular complications following 1500 consecutive living and cadaveric donor renal transplantations: A single center study. Saudi J Kidney Dis Transpl [serial online] 2009 [cited 2013 May 18];20:570-2. Available from: http://www.sjkdt.org/text.asp?2009/20/4/570/53243
| Introduction|| |
Renal transplantation is accepted as the preferred treatment for most cases of end-stage renal disease. Despite improvement in surgical and diagnostic techniques, vascular complications following kidney transplantation remain an important clinical problem that may increase morbidity, hospitalization and costs.  Post transplant vascular complications include stenosis or thrombosis of the transplant renal artery or vein, hemorrhage or arteriovenous fistulas after biopsy. Impaired arterial perfusion of the transplant may be an important cause of graft dysfunction or refractory hypertension.  Therefore, knowledge of the incidence, clinical manifestations and management of vascular complications is necessary for all kidney transplant surgeons.
In this study, we aimed at evaluating the incidence of vascular complications among 1500 recipients of living and cadaveric donor renal transplantations, as well as to assess the possible risk factors.
| Materials and Methods|| |
We conducted a retrospective study on 1500 consecutive renal transplanted patients (4-70 years old) who received a living or cadaveric donor kidney between December 1988 and July 2006 in a regional transplant center (Nemazee Hospital affiliated to Shiraz University of Medical Sciences, Iran). This period was relatively homogenous in terms of general clinical management following kidney transplantation. All transplants were performed by the same experienced surgical team, which was sufficiently trained for performing kidney transplantation.
Demographic and clinical data at the time of transplantation and during hospitalization were collected by chart review. Patients were divided into three groups depending on their donors: Living related, living unrelated and cadaveric. The anatomy and number of renal arteries were noted from the angiography reports, which was performed for all living donors before the operation, and from the operation notes. Vascular complications were diagnosed by using color doppler sonography that was performed within the first 24 hours in all recipients as well as angiography or surgical exploration, which were performed in clinically suspected cases. The immunosuppressive protocol used in our transplant unit comprised of cyclosporine (CsA), imuran or cellcept, and prednisolone in all study patients. The surgical technique used for all transplantations was the accepted standard procedure of placing the allograft in either the right or the left iliac fossa by using an extra-peritoneal approach.
Categorical variables were analyzed using the chi-square test. P < 0.05 was considered statistically significant. Results are reported as means ± SD. Statistical analysis was performed using SPSS 11.5 (Chicago, IL, USA)
| Results|| |
Among the 1500 study patients, the male: female ratio was 2.05 (1008 males, 492 females). The mean age was 33.92 ± 13.02 years. A total of 1203 patients (80.2%) received kidneys from living donors (616 cases were from living related donors, 587 were from living unrelated ones) and 297 patients (19.8%) received kidneys from cadaveric sources. Vascular anatomic variations noted in the allograft were as follows: 1264 allografts (84.3%) had only one renal artery, 222 (14.8%) had two arteries and 14 allografts (0.93%) had more than two arteries. Furthermore, 1441 kidneys (96.1%) had only one renal vein, and 58 (3.8%) had two veins. One allograft was found to have four renal veins while four kidneys had four renal arteries each.
Clinically apparent vascular complications were seen in 8.86% (n = 133) of all study patients. The most frequent vascular complications were hemorrhage seen in 6.1% (n = 91) of the cases followed by renal arterial stenosis seen in 1.7% (n = 26), renal artery thrombosis in 0.6% (n = 9), and renal vein thrombosis seen in 0.5% (n = 7) of the patients. Rare vascular complications included arteriovenous fistulas and aneurysms (each less than 0.1%). Among the 1204 recipients of living donor kidneys, 96 patients (7.97%) had vascular complications while 37 (12.5%) of the 296 recipients of cadaveric kidneys developed vascular complications (P= 0.017). The frequency of occurrence of vascular complications was significantly higher among recipients of renal allografts with multiple arteries rather than single artery (12.3% vs. 8.2%; P= 0.033). Additionally, only 8.2% of recipients of allografts with single renal vein developed vascular complications while 25.4% of those with multiple veins experienced vascular complications (P< 0.001). There was no significant differrence in the frequency of vascular complications between male and female recipients (8.1% vs. 10.4%; P= 0.17).
| Discussion|| |
One of the important complications after renal transplantation is vascular complications. Among them, thrombosis, transplant renal artery stenosis, and hemorrhage are three troublesome complications that could affect patient as well as graft survival. 
The incidence of thrombotic complications in our series was only 0.5% which is close to the report of Osman Y et al.  However, this figure is much lower than the 0.8 to 6% prevalence seen in recipients of cadaveric donor kidneys.  , In both studies, living donors comprised the majority of organ donors. In our study, vascular complications occurred less frequently following living donor renal transplantation compared to cadaveric donor transplantation (P= 0.017). Living donor renal transplantation is usually performed under more favorable circumstances. These donors are evaluated scrupulously for evidence of atherosclerosis, diabetes, and/or any degenerative or vascular impediments before operation. However, cadaveric donor transplantations are usually performed in less elective situations. In our center, both living as well as cadaveric donor transplants are performed by the same team of highly experienced urologists, making technical errors almost negligible.
Transplant renal artery stenosis is a primary and potentially reversible cause of hypertension and graft loss.  Although invasive, angiography is the gold standard for assessing this pathological condition. The role of doppler ultrasound and magnetic resonance angiography is still controversial.  Depending on the methodology used for diagnosis, the reported incidence of transplant renal artery stenosis is 1 to 16%. 
The 1.7% incidence of transplant renal artery stenosis in our series is quite low compared with that of other reports and could be attributable, at least in part, to the fact that we used conventional angiography for diagnosis. The other reason may be the large number of living donor transplantations performed in our study patients. In accordance with previous literature, we found more vascular complications among recipients of allografts with multiple renal blood vessels. These allografts should be managed with care, both during bench preparation and surgical suturing. Generally, vascular anastomosis in renal transplantation should be performed meticulously, so that vascular complications are avoided.
| Acknowledgements|| |
The authors would like to thank Miss Gholami and Mrs. Ghorbani at Center for Development of Clinical Research of Nemazee Hospital for editorial and typing assistance.
| References|| |
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Assistant Professor of Urology, Fellowship of Renal Transplantation Division of Urology, Department of Surgery, Faghihi Hospital, Shiraz