Renal Allograft Compartment Syndrome: Is It Possible to Prevent?

Contrast-enhanced US in Renal Transplant Complications: Overview and Imaging Features

Renal transplant is the first-line treatment of end-stage renal disease. The increasing number of transplants performed every year has led to a larger population of transplant patients. Complications may arise during the perioperative and postoperative periods, and imaging plays a key role in this scenario. Contrast-enhanced US (CEUS) is a safe tool that adds additional value to US. Contrast agents are usually administered intravenously, but urinary tract anatomy and complications such as stenosis or leak can be studied using intracavitary administration of contrast agents. Assessment of the graft and iliac vessels with CEUS is particularly helpful in identifying vascular and parenchymal complications, such as arterial or venous thrombosis and stenosis, acute tubular injury, or cortical necrosis, which can lead to graft loss. Furthermore, infectious and malignant graft involvement can be accurately studied with CEUS, which can help in detection of renal abscesses and in the differentiation between benign and malignant disease. CEUS is also useful in interventional procedures, helping to guide percutaneous aspiration of collections with better delimitation of the graft boundaries and to guide renal graft biopsies by avoiding avascular areas. Potential postprocedural vascular complications, such as pseudoaneurysm, arteriovenous fistula, or active bleeding, are identified with CEUS. In addition, newer quantification tools such as CEUS perfusion are promising, but further studies are needed to approve its use for clinical purposes. ©RSNA, 2024 Supplemental material is available for this article.

Children Are Not Small Adults: Similarities and Differences in Renal Transplantation Between Adults and Pediatrics

Kidney transplantation is the treatment of choice for all patients with end-stage kidney disease, including pediatric patients. Graft survival in pediatrics was lagging behind adults, but now is comparable with the adult cohort. Although many of the protocols have been adopted from adults, there are issues unique to pediatrics that one should be aware of to take care of this population. These issues include recipient size consideration, increased incidence of viral infections, problems related to growth, common occurrence of underlying urological issues, and psychosocial issues. This article addresses the similarities and differences in renal transplantation, from preparing a patient for transplant, the transplant process, to post-transplant complications.

Introducing a New Technique for Fascial Closure to Avoid Renal Allograft Compartment Syndrome in Pediatric Recipients: The Use of Tutoplast® Fascia Lata

Introduction

Renal allograft compartment syndrome (RACS) is a complication that infrequently occurs after renal transplantation. Tight muscle closure may lead to RACS due to compression of renal parenchyma or kinking of the renal vessels. Many techniques have been proposed in an attempt to achieve tension-free closure, which can be specially challenging in child recipients. We present our experience with Tutoplast^® Fascia Lata (RTI Surgical Tutogen Medical GmbH Industriestrasse 6, 91077 Neunkirchen am Brand, Germany) closure.

Methods

All pediatric patients who underwent renal transplantation in our center between 2012 and 2021 were reviewed. Eight patients with Tutoplast^® Fascia Lata placed at the time of initial transplantation were identified. Donor and recipient characteristics, Doppler ultrasound findings, and overall patient and graft survival rates were analyzed.

Results

Doppler ultrasound was performed intra-operatively after abdominal wall closure. If any sign of vascular compromise was seen, the abdominal wall was opened and the graft was revised. The Tutoplast^® Fascia Lata implant was used to perform tension-free fascia closure and, afterwards, a Doppler ultrasound was performed to confirm the optimal renal artery perfusion and venous patency. Three of the renal transplantations were from a cadaver donor, with two of them en bloc. Living donor transplantation was performed in four cases. Among which, there was a case of auto-transplantation due to bilateral renal artery stenosis. None of the patients presented any complications of either short or long term that was derived from the abdominal closure with Tutoplast^® Fascia Lata. There was also no record of graft failure till datum.

Conclusions

Restricted volume of the recipient pelvic cavity and the size discrepancy between the recipient pelvic cavity space and the donor adult kidney may lead to RACS. Other situations that occur more infrequently, i.e., as en bloc or auto-transplantation, are prone to suffer the same problem. Tutoplast^® Fascia Lata is a safe option for these patients.

Renal allograft compartment syndrome: a review

Renal allograft compartment syndrome (RACS) is the result of extrinsic compression resulting in graft dysfunction and loss due to ischaemia. A literature review was performed by computerized searches from the following data sources Medline, EMBASE, PubMed and Cochrane Library databases. Risk factors include size mismatch between graft and recipient. Intraoperative suspicion should be exercised if there is poor tissue turgor, cyanosis and loss of urine output upon fascial closure. Doppler ultrasound is the modality of choice amongst the literature to aid in diagnosis of RACS. From our study, the accepted form of treatment is early detection and appropriate surgical intervention. Nevertheless, it is clear from the paucity of literature that further investigation into this area of transplantation is necessary.

Comparison of live donor predonation and post-transplant kidney volumes and glomerular size in pediatric patients weighing less than 15 kg - a retrospective study

Renal transplantation of adult-size kidneys presents a size mismatch in small children. This study presents a comparison of live donor predonation and recipient post-transplant kidney volumes (k-vol) and glomerular size at 1 year after transplantation. We analyzed 47 pediatric renal transplant recipients weighing <15 kg between 2009 and 2017. The k-vol before and 1 year after transplantation and glomerular size at implant and 1 year post-transplant were evaluated. We estimated the relationships between these changes and graft function, and the factors associated with k-vol. Pretransplant k-vol was 158.1 ± 25.1 ml, and the k-vol at 1 year post-transplant was significantly reduced by -17.2% to 132.3 ± 27.3 ml (P < 0.001). Implant glomerular size showed the diameter was 165.3 ± 15.1 µm and the area 20 737.1 ± 3230.6 µm² . One-year post-transplant, the glomerular diameter was 150.6 ± 11.4 µm and the area 17 428.3 ± 2577.9 µm² , significantly reduced compared with implantation values (both P < 0.001). The change in k-vol was affected by pretransplant abdominal cavity (ml/200 ml cavity volume, partial regression coefficient = 0.029, SE = 0.009, P = 0.004) and recipient's weight gain (ml/5% of weight gain, partial regression coefficient = 0.020, SE = 0.006, P = 0.002). In small pediatric transplants, an adult-size kidney is acceptable with reduction in k-vol. Moreover, the post-transplant k-vol might be regulated by pretransplant physique and post-transplant somatic growth.

Transplantation of adult-size kidneys in small pediatric recipients: A single-center experience

RTx of adult-size kidneys presents a size mismatch in small pediatric recipients, and there are potential surgical complications. This study reveals the outcomes of intra- and extraperitoneal RTx in low-weight (less than 15 kg) pediatric recipients. We studied 51 pediatric patients weighing less than 15 kg who received a living-related donor renal transplant between 2009 and 2017. The intraperitoneal (group A, n = 24) and extraperitoneal (group B, n = 27) approaches were compared. In group A, the mean age, Ht, and weight were 3.8 ± 1.6 years, 83.7 ± 6.5 cm, 10.5 ± 1.8 kg; in group B, 5.0 ± 1.9 years, 95.3 ± 7.3 cm, and 13.0 ± 1.4 kg. Single renal artery grafts (21 in group A and 16 in group B) and double renal artery grafts (three in group A and 11 in group B) were performed. Of the patients with double renal artery transplants, one in group A and six in group B underwent ex vivo arterial reconstruction. The eGFR (mL/min/1.73 m² ) at 1-week post-transplant in group A was significantly higher than that in group B; the eGFRs at 4 weeks post-transplant did not differ. One graft was lost in group B because of vascular thrombosis. Post-transplant complications included ileus and transplant ureteral stenosis. There was no significant difference in 5-year graft survival rate (group A 100%, group B 91.7%). Both transplant approaches are feasible to adapt to a size mismatch between the adult-size donor kidney and low-weight pediatric recipients.

Patient Selection for Kidney Transplant

The incidence of end-stage renal disease has continued to increase. Similarly, the number of patients living with a functioning renal allograft has also increased. Transplantation has improved with advances in surgical techniques, immunosuppression, and better control of comorbid conditions. Transplantation is transformative and offers the greatest potential for restoring a healthy, productive, and durable life to appropriately selected patients. This article describes factors to address in selection of renal transplant candidates and discusses commonly encountered perioperative events. Paramount to selecting appropriate candidates is the collaboration between a multidisciplinary team focused on a systematic process guided by protocols and common practices.

Retroperitoneal Compartment Syndrome in Renal Transplantation: How to Salvage the Graft?

OBJECTIVE

Early allograft dysfunction may be caused by several technical factors including vascular complications such as thrombosis, kinking, or extrinsic compression. Renal allograft compartment syndrome (RACS) is an unrecognized cause of early allograft dysfunction. This complication is characterized by increased pressure of the iliac fossa that reduces the blood supply to the graft with a potentially devastating consequence. The main objective when recognizing this condition is to create a tension-free muscle closure. Many approaches have been proposed involving mesh such as the mesh hood fascial closure technique.^1-4 PATIENT AND METHODS: We describe in the video an RACS during an operation. The recipient is a 23-year-old young man with a body mass index of 22, with renal failure secondary to chronic reflux. Past history of failure to peritoneal dialysis currently on hemodialysis. He received a living donor's kidney. After performing a standard anastomosis, his urine output was brisk. The fascia was then closed with no force, at which point he stopped making urine. A RACS was suspected; intraoperative examination and ultrasound showed no flow in the graft, with no signs of kinking. Immediately, reexploration was performed, showing the graft with abnormal color and turgor. After relieving the pressure, the graft returned to normal. The closure was redone with a large ellipsoid piece of polypropylene mesh draped loosely and without tension over the graft.

RESULTS

A Doppler ultrasound, after the skin closure was performed, showed good flow, and the postoperative course was unremarkable. There was minimal bulking in the right iliac area, making it cosmetically acceptable.

CONCLUSION

RACS could be associated with a lack of compliance in the retroperitoneal cavity.⁵ The RACS required a prompt intervention. The timely suspicion is a watershed in the prognosis of this rare pathology. We propose that mesh hood fascial closure is easy, effective, and a safe method to treat these complications.