Complications chirurgicales de la transplantation rénale

Infections in Kidney Transplant Recipients: Perspectives in French Caribbean

Few studies have focused on the infectious complications in kidney transplant recipients in tropical regions, particularly in the Caribbean. The primary objective of this study was to determine the incidence of bacterial, fungal, and parasitic infections in kidney transplant recipients in the French Caribbean and French Guiana. We included all patients who received a kidney transplant at the University Hospital of Guadeloupe between January 2014 and October 2016, with post-transplant follow-up in the French Caribbean. A total of 91 patients were included, of whom 57 developed an infectious event during follow-up. When infections were documented (94/111), bacterial infections were the most frequent (79/94), followed by fungal (11/94) and parasitic infections (4/94). Four cases of nocardiosis were identified (4/79). Phaeohyphomycosis was the most common fungal infection (7/11). In a multivariate analysis, the female gender and diabetes mellitus at the time of transplant were significantly associated with a higher risk of infection. This study is the first to describe the epidemiology of infections in kidney transplant recipients in the Caribbean and to analyze the potential risk factors. We reported a similar profile of bacterial infections to that which were observed in the European and American studies. However, we found a higher incidence of tropical infections, such as nocardiosis and phaeohyphomycosis, which highlights the need for heightened awareness among healthcare teams to ensure earlier and more appropriate treatment. Further studies focusing on these rare tropical infections are necessary to better understand their risk factors.

Impact of Transplantation Timing on Renal Graft Survival Outcomes and Perioperative Complications

Nighttime organ transplantation aims to decrease cold ischemia duration, yet conflicting data exists on its impact on graft function and perioperative complications. This multicenter TRANSPLANT'AFUF study including 2,854 patients, transplanted between 1 January 2011, and 31 December 2022, investigated nighttime kidney transplantation's impact (8:00 p.m.-8:00 a.m.) versus daytime (8:00 a.m.-8:00 p.m.) on surgical complications and graft survival. Overall, 2043 patients (71.6%) underwent daytime graft, while 811 (28.4%) underwent nighttime graft. No impact was observed of timing of graft surgery on graft survival with a median survival of 98 months and 132 months for daytime and nightime grafting, respectively (p = 0.1749). Moreover, no impact was observed on early surgical complications (Clavien I-II = 20.95% for DG and 20.10% for NG; Clavien III-IV-V = 15.42% for DG and 12.94% for NG; p = 0.0889) and late complications (>30 days) (Clavien I-II = 6.80% for DG and 5.67% for NG; Clavien III-IV-V = 12.78% for DG and 12.82% for NG; p = 0.2444). Noteworthy, we found a significant increase in Maastricht 3 donors' rates in nighttime transplantation (5.53% DG vs. 21.45% NG; p < 0.0001). In conclusion, nighttime kidney transplantation did not impact early/late surgical complications nor graft survival.

Frequency of Complications After Kidney Transplant in the Early Postoperative Period

OBJECTIVES

Complications after kidney transplant can be divided into surgical and nonsurgical. Our study investigated the incidence of postoperative complications and types of complications in a single center.

MATERIALS AND METHODS

We retrospectively analyzed the occurrence of postoperative complications in 220 patients who underwent kidney transplantation at the Republican Scientific Center for Emergency Medical Care (Tashkent, Republic of Uzbekistan) from January 2019 to October 2022.

RESULTS

Among the 220 patients, various types of complications were observed in 42 cases (19.1%). Of these, 31 patients (73.8%) had surgical complications and 11 patients (26.2%) had nonsurgical complications. Surgical complications included hematoma of the postoperative wound in 8 patients (19.2%), thrombosis of the graft artery in 1 patient (2.4%), thrombosis of the venous anastomosis in 1 patient (2.4%), lymphocele of the postoperative wound in 7 patients (16.6%), wound infections 4 patients (9.5%), bleeding from the arterial anastomosis 2 patients (4.7%), bleeding from the venous anastomosis 1 patient (2.4%), kink of the venous anastomosis in 3 patients (7.2%), postoperative hernia in 2 patients (4.7%), and urological complications in the form of ureteral necrosis in 2 patients (4.7%). Nonsurgical complications included hyperacute rejection, which led to the removal of the graft, in 2 patients (4.8%), acute cellular rejection of the graft, which was successfully treated with methylprednisolone pulse therapy, in 4 patients (9.5%), delayed graft function in 1 patients (2.4%) case, and posttransplant diabetes mellitus in 4 patients (9.5%).

CONCLUSIONS

Despite the frequency of postoperative complications, timely assistance and further monitoring of patients can lead to normal functioning of the kidney transplant, except for cases of hyperacute rejection.

[Surgical outcomes and complications following third kidney transplantation]

BACKGROUND

After two consecutive kidney transplant failures, a third kidney transplantation improves survival for patients on the waiting list. The surgical outcomes and complications of third kidney transplantations remain poorly known.

METHODS

We analyzed the last 100 third kidney transplantations performed in our center between January 2000 and August 2018. The data, relating to donors and recipients, were extracted retrospectively from medical records and from the prospective DIVAT database (computerized and validated data in transplantation). Continuous variables are expressed as means, medians, first and third quartiles (median, [Q1;Q3]). Categorical variables are expressed as percentages. Patient and transplant survivals were calculated using the Kaplan-Meier method.

RESULTS

Mean age of recipients was 46.4 years (47, [36;53]). Thirty-five percent had kidney failure due to urinary tract malformations. Mean age of donors was 48.2 years (52, [39.75; 58]) with 63% of donors with standard criteria. Mean cold ischemia time was 22.4hours (21, [16.5; 29.2]). Surgical mortality rate was 2% and surgical complication rate was 45%. Third kidney transplants survival was 73.1% and 58.8% at 5 years and 10 years. Mortality rate with a functioning transplant was 18%.

CONCLUSION

A third kidney transplant offers satisfactory functional outcomes but remains associated with high morbi-mortality and a significant death rate with a functioning transplant.

LEVEL OF EVIDENCE: 4

Kidney transplantation from expanded criteria donors: an increased risk of urinary complications - the UriNary Complications Of Renal Transplant (UNyCORT) study

OBJECTIVES

To assess the impact of expanded criteria donors (ECD) on urinary complications in kidney transplantation.

PATIENTS AND METHODS

The UriNary Complications Of Renal Transplant (UNyCORT) is a cohort study based on the French prospective Données Informatisées et VAlidées en Transplantation/Computerized and VAlidated Data in Transplantation (DIVAT) cohort. Data were extracted between 1 January 2002 and 1 January 2018 with 1-year minimum follow-up, in relation to 44 pre- and postoperative variables. ECD status was included according to United Network for Organ Sharing (UNOS) definition. The primary outcome of the UNyCORT study was the association between the donor's ECD/standard criteria donors (SCD) status and urinary complications at 1 year in uni- and multivariate analysis. Sub-group analysis, stratified analysis on ECD/SCD donor's status and transplant failure analysis were then conducted.

RESULTS

Between 1 January 2002 and 1 January 2018, 10 279 kidney transplants in adult recipients were recorded within the DIVAT network. A total of 8559 (83.4%) donors were deceased donors and 1699 (16.6%) were living donors (LD). Among donation after circulatory death (DCD) donors, 224 (2.85%) were uncontrolled DCD and 93 (1.09%) were controlled DCD donors. A total of 3617 (43.9%) deceased donors were ECD. The overall urological complication rate was 16.26%. The donor's ECD status was significantly associated with an increased risk of urological complications at 1 year in multivariate analysis (odds ratio: 1.50, 95% CI 1.31-1.71; P < 0.001) and especially with stenosis and ureteric fistulae at 1 year. There is no association with LD, uncontrolled and controlled DCD. The placement of an endo-ureteric stent was beneficial in preventing urinary complications in all donors and particularly in ECD donors.

CONCLUSION

The donor's ECD status is associated with a higher likelihood of stenosis and ureteric fistulae at 1 year. Recipients of grafts from ECD donors should probably be considered for closer urological monitoring and systematic preventive measures.

Management of long ureteral stenosis: Alternatives to indwelling ureteral stents

OBJECTIF

Evaluate kidney autotransplantation (KAT) and ileal ureter substitution (IUS) practice and outcome as alternatives to indwelling ureteral stents for the management of long ureteral stenosis (US).

MATERIAL

We included all patients treated for US with KAT or IUS in 5 French university urology centers between 2010 and 2018. We excluded US due to urothelial carcinoma. Primary endpoint was the preservation of ipsilateral kidney and renal function without any urinary diversion.

RESULTS

22 patients were treated with KAT (n=8, 36.4%) and IUS (n=14, 63.6%). Mean US length was 4.6cm and 6cm (P=0.52) in KAT and IUS groups respectively. US etiologies were lithiasis, iatrogenic, retroperitoneal fibrosis or extrinsic compression. US level was varied. The surgery was described as difficult because of peritoneal adhesions or major peri-ureteral fibrosis. Mean operating time and hospital stay were 336 and 346minutes (P=0.87) and 8 and 15 days respectively (P=0.001). Postoperative complications were mostly Clavien ≤2 (n=17, 77.3%). Revision surgery was required in the KAT group in 3 cases (37.5%), for textiles, renal vein thrombosis and anastomotic leak, none in the IUS group. The mean follow-up was 15.7 months. All but one (in the KAT group) ipsilateral kidneys were preserved, without renal function impairment (Δcreat +2.1 vs. +2.4μmol/l respectively, P=0.67), nor urinary diversion.

CONCLUSION

KAT and IUS are safe alternatives whose indication depends on surgeons expertise. Our study pointed out the scarcity of this practice suggesting the need to refer patients to expert centers.

LEVEL OF EVIDENCE

3.

Urological Complications in Kidney Transplant Recipients: Analysis of the Risk Factors and Impact on Transplant Outcomes in the Era of “Extended Criteria Donors”

Urological complications (UC) following kidney transplantation (KT) are associated with increased morbidity. The aim of this study is to evaluate the risk factors for UC in the era of “extended criteria donors” (ECD) and their impact on patient and graft survivals. A retrospective monocentric study of all patients undergoing KT from 2010 to 2019 with a follow-up ≥30 days was performed. Out of 459 patients (males: 296 (64.5%); age: 57 (19–77) years) enrolled, 228 (49.7%) received ECD organs, moreover, 166 (67.2%) grafts had a cold ischemia time ≥10 h. UCs were reported in 32 (7%) patients. In 21 (65.6%) cases UC occurred within 3 months post-KT and 24 (5.2%) were associated with early urinary tract infection (UTI). The overall 5 year patient and graft survival rates were 96.5% and 90.6%, respectively. UC decreased graft survival (UC-group: 75.0% vs. noUC-group: 91.8%, p < 0.001), especially if associated with early UTI (UC-group: 71.4% vs. noUC-group: 77.8%, p < 0.001). At multivariate analysis, early UTI after KT (OR: 9.975, 95%-IC: 2.934–33.909, p < 0.001) and delayed graft function (DGF) (OR: 3.844, 95%-IC: 1.328–11.131, p: 0.013) were significant risk factors for UC, while ECD graft did not increase the risk of post-transplant UC. ECD grafts are not associated with UC. DGF and early UTI post-KT increase the risks of UC and reduce graft survival in the long-term. Therefore, aggressive management of early post-transplant UTI and strategies to reduce DGF incidence, such as machine preservation, are essential to prevent UC after KT.

[Results of surgical revisions for ureteral complications after renal transplantation]

OBJECTIVE

To analyze the results of surgical revision for ureteral complication (ureteric stenosis or urinary leakage) after renal transplantation over a period of 10 years.

MATERIALS AND METHODS

We performed a retrospective study on 1313 consecutive kidney transplantations carried out in a University Hospital Center between 2005 and 2014. The data of the patients who developed a ureteral stenosis or a urinary leakage secondary to a renal transplantation were analyzed. Combined organ transplantations (kidney-liver and kidney-pancreas), as well as pediatric transplantations were excluded.

RESULTS

Seventy-six patients (5.8%) had ureteric stenosis or urinary leakage after renal transplantation. Forty-six patients (3.5%) underwent surgical revision: 27 for ureteral stenosis, 19 for urinary leakage. Early success was achieved in 26 patients (56.5%), including 14 ureteric stenosis (51.9%) and 12 urinary leakage (63.2%) (P=0.45). After a complementary endoscopic or surgical treatment, the final success rate was increased to 73.1% (34 patients): 20 ureteric stenosis (74.1%) and 14 urinary leakage (73.7%) (P=0.98). There were 2 graft losses (4.3%) and one death (2.2%). The mean glomerular filtration rate estimated by the MDRD was 44.58mL/min/1.73m² (±14.7) before surgery and 45.37mL/min/1.73m² (±16.5) 6 months after surgery (P=0.92).

CONCLUSION

Although frequently challenging, surgical revisions for ureteral complications after renal transplantation give good results, with a low rate of graft loss and mortality.

LEVEL OF EVIDENCE

4.

Antioxidant and nephroprotection activities of Combretum micranthum: A phytochemical, in-vitro and ex-vivo studies

Management of chronic renal failure is exceedingly expensive. Despite of encouraging experimental outcomes, there is a lack of potent nephroprotective drugable molecules in a clinics or market. To develop a nephroprotective phytomedicine, the present study was designed to do a literature survey on reported phytochemical and biological analysis of Combretum micranthum and to carry out chemoprofiling, in-vitro antioxidant and ex-vivo nephroprotective capacity of the title plant. The phytochemical and biological activity survey of C. micranthum has reveals the presence of many bioactive compounds such as flavonoids, terpenoids, steroids and alkaloids with many biological activities. Phytochemical investigation re-confirmed the presence of these compounds. Hydroalcoholic extract of C. micranthum (CM extract) showed a strong antioxidant activity by scavenging AAPH, DPPH, nitric oxide, hydrogen peroxide and chelating metal ions. CM extract exhibited significant (P < 0.001) dose dependent inhibition of ferric chloride-ascorbic acid induced lipid peroxidation. Diabetic nephropathy is a serious and common complication leading to end stage renal disease. Therefore, in the present study, glucose-induced toxicity was also studied in human embryonic kidney cells (HEK-293) as an in vitro model for diabetic nephropathy. The results showed that exposure of cells to high glucose (100 mM) for 72 h significantly reduced the cell viability resulting in morphological changes such as cell shrinkage, rounded cell shape and cytoplasmic vacuolation. Treatment with CM extract at 10 and 25 μg/mL resulted in significant improvement in cell viability from 10 to 23% compared to the high glucose control. This study demonstrated the potential antioxidant and nephroprotective properties of C. micranthum, justifying its traditional use in the treatment of various diseases.

Renogram in kidney transplant. Utility of delayed images with SPECT/CT in the diagnosis of urinary leak

Urinary leakage in patients with kidney transplantation is a relatively common surgical complication that requires early diagnosis and intervention. The isotopic renogram is a non-invasive and effective method to evaluate the perfusion and function of kidney transplantation, and allows us to diagnose urological complications such as urinary leakage. In these cases, it is useful to complete the study with planar images and delayed SPECT/CT to specify the diagnosis and locate the leak. We expose two cases diagnosed with urinary leak after performing a renogram with early and delayed planar images and delayed SPECT/CT a week after transplantation. In both cases, a percutaneous nephrostomy catheter was placed, as well as a double J catheter, resolving the surgical complication.