Segmental infarction with graft dysfunction: an emerging syndrome in renal transplantation?

Partial Nephrectomy of Transplanted Kidney with Calyceal Fistula

Kidney transplant is the established treatment for patients with chronic kidney disease but is associated with complications due to the complexity of the procedure. Calyceal fistulas are rare urological complications in transplants caused by arterial occlusion with segmental infarction of the graft. Treatment is based on the extension of the affected area and the clinical status of the patient. For extensive infarctions treated surgically, a total nephrectomy of the transplanted kidney is generally performed. We present a case of a transplanted kidney with polar necrosis and calyceal fistula treated with partial nephrectomy of the affected area, maintaining the graft and preserving kidney function.

Early critical cortical infarction by anti-angiotensin II type 1 receptor antibody: A case report and literature review

RATIONALE

Anti-angiotensin II type 1 receptor antibodies (AT1R-Abs) have been demonstrated to increase the risk of antibody-mediated rejection. We report a case of AT1R-Ab mediated rejection which caused early critical cortical infarction.

PATIENT CONCERNS

A 52-year-old man with end-stage kidney disease underwent preemptive kidney transplantation (KT) from his wife. He had no immunologic risk except ABO incompatibility. Proper desensitization treatment were applied prior to KT. On postoperative day 1, he showed stable clinical course with adequate urine output, but there was no decrease in serum creatinine level and imaging studies showed hypoperfusion in the transplanted kidney.

DIAGNOSES

Allograft biopsy revealed total cortical infarction with severe necrotizing vasculitis, but the medullary area was preserved. Serum AT1R-Ab concentration was elevated from 10.9 U/mL before KT to 19.1 U/mL on 7 days after KT.

INTERVENTIONS

He was treated with plasmapheresis, intravenous immunoglobulin, rituximab, high-dose methylprednisolone, and bortezomib.

OUTCOMES

The treatment showed a partial response, and he was discharged with 7.3 mg/dL creatinine level. At 4 months, his creatinine plateaued at 5.5 mg/dL and AT1R-Ab decreased to 3.6 U/mL.

LESSONS

This case highlights the risk of early active antibody-mediated rejection by preformed AT1R-Ab, suggesting its ability to exhibit atypical histopathologic findings, such as total cortical infarction.

Acute allograft dysfunction mimicking thrombotic microangiopathy in kidney transplant recipient with renal infarction: case report and review of literatures

Acute allograft dysfunction is rarely observed in kidney transplantation (KT). We report an unusual case of acute allograft dysfunction mimicking thrombotic microangiopathy (TMA) in recipient with renal infarction. A 65-year-old man underwent KT from his 39-year-old son. Pre-transplant donor evaluation was normal except for the branches of the upper and lower pole renal arteries originating from the aorta in renal computed topographic angiography, respectively. The immediate post-transplant clinical course was uneventful, but serum creatinine (SCr) increased from 2.2 to 4.5 mg/dL, anemia and thrombocytopenia were shown, and serum lactate dehydrogenase increased to 919 U/L on the third day after transplantation. We suspected TMA, because of no evidence of acute bleeding. The laboratory parameters associated with TMA were within normal ranges. Renal magnetic resonance angiography revealed a focal wedge-shaped perfusion defect in the upper pole of the graft and renal Doppler ultrasonography showed decreased perfusion of the lower pole of the graft. Graft function improved with conservative therapy. The patient was discharged with SCr of 1.21 mg/dL. Graft function has been stable after discharge. Acute allograft infarction should be considered in the differential diagnosis of acute allograft dysfunction mimicking TMA in recipients with grafts supplied by multiple renal arteries.

The prevalence and significance of renal perfusion defects in early kidney transplants quantified using 3D contrast enhanced ultrasound (CEUS)

OBJECTIVES

Vascular complications are one of the most common causes of early kidney transplant dysfunction. Contrast enhanced ultrasound increases sensitivity to vascular changes. The aim of this study was to assess the prevalence and size of vascular abnormalities in early renal transplants using 3D CEUS and the significance of perfusion defects on renal function.

METHODS

Ninety-nine renal transplant patients underwent 3D CEUS after surgery to quantify perfusion defects as percentage total renal volume (TRV). Serum creatinine and estimated glomerular filtration rate (eGFR) were recorded up to 3 months post-surgery.

RESULTS

Twenty participants had focal perfusion defects (0.2-43%TRV). There was a meaningful difference in patients with perfusion defects in eGFR at 1 month (90% CI 2.7-19.2 mL/min/1.73 m²) and 3 months (90% CI 1.9-19.6 mL/min/1.73 m²) and creatinine at 3 months (90% CI -56 - -8 μmol/L) using a predetermined clinical threshold. Perfusion defect size correlated well with both serum creatinine and eGFR at 3 months (R = 0.80, p ≤ 0.000 and 0.58, p = 0.038). No correlation was seen prior to 3 months.

CONCLUSIONS

Perfusion defects in kidney transplants were more common than expected and were highly likely to reduce renal function at 1-3 months, and the size of the defect affected the degree of functional change at 3 months.

KEY POINTS

• Perfusion defects were more common than previously thought. • Perfusion defects could be quantified using 3D CEUS. • The presence of even small perfusion defects may affect kidney function. • Size of perfusion defects correlated with subsequent kidney function at 3 months. • Potentially useful in informing clinician expectations of kidney function post-surgery.

The Potential for CEUS to Detect Segmental Renal Allograft Infarction

This case study provides a report on a patient who had a segmental renal allograft infarction. The cause of this infarction within the segmental vessels was theorized to be due to prolonged warm ischemia within the organ donor. The area of infarction was visualized by the use of contrast-enhanced ultrasound (CEUS). This report raises the question as to whether routine sonographic imaging can demonstrated the sequence of infarction within a fresh renal allograft, as is routinely noted in native kidneys. This report highlights the importance of taking the segmental infarction into consideration when approaching the renal allograft recipient. CEUS could provide an important clinical application for the diagnosis of renal allograft infarctions and avoid more invasive procedures. Knowledge of the lack of sequence of sonographic changes in renal allograft infarction helps in assessing the function and outcomes of renal allograft recipients.

Urinary fistula repair in a renal graft through a partial nephrectomy and omentoplasty

OBJECTIVES

We present the management with partial nephrectomy and interposition of the greater omentum in case of urinary fistulas in renal allograft.

MATERIAL AND METHOD

We present a patient with necrosis at the inferior pole of the renal graft that affected calyceal system but with pyeloureteral vascularization preserved. The patient's condition was satisfactorily managed with a partial nephrectomy of the necrotic renal segment and primary suturing of the collecting system with interposition of the greater omentum. We reviewed the cases published to date of partial nephrectomy in renal allograft, and examined their outcomes by analyzing the patient presentation, diagnostic tools, and surgical techniques used.

RESULTS

There are few cases in the current literature that describe conservative surgical management of urinary fistulas caused by segmental necrosis after renal transplantation. Surgical approach using partial nephrectomy in these cases produces favorable outcomes in our experience and reported cases.

CONCLUSIONS

Despite its obvious surgical complexity, this nephron-sparing management is feasible and should be implemented in cases where the prior renal function and the quantity of healthy parenchyma indicate a favorable subsequent evolution for the renal graft.

Renal cortical infarction following treatment with sumatriptan in a kidney allograft recipient

Renal cortical infarction is a rare cause of acute kidney injury that results from inadequate blood flow to the kidney, most commonly as a consequence of thrombotic or embolic occlusion of the renal artery or profound hypoperfusion. We report the case of a 78-year-old female kidney transplant recipient who developed a migraine headache, took sumatriptan, and soon after developed pain over the allograft and oligoanuric acute kidney injury. Kidney allograft biopsy showed renal cortical infarction. The mechanism of action of sumatriptan involves vasoconstriction, which counters the vasodilatation that is central to the pathogenesis of migraines. This case raises important questions regarding the safety of triptans with calcineurin inhibitors (which also act to vasoconstrict), particularly in elderly patients.

Kidney Transplant with Multiple Renal Artery Grafts from Deceased Donors: Are Long-Term Graft and Patient Survival Compromised?

Background—

Kidneys with multiple arteries are often transplanted. However, the long-term outcome of such kidneys recovered exclusively from deceased donors is not clear.

Objective—

To determine whether use of renal grafts with multiple arteries affects long-term graft survival and function.

Methods—

The outcomes of 259 consecutive kidney transplants between 1996 and 2000 were retrospectively reviewed. Patients were divided into 2 groups, multiple renal artery graft recipients (n = 70) and single renal artery graft recipients (n = 189). Short-term complications and long-term outcomes (survival rates, blood pressure after transplant, creatinine clearance, and proteinuria levels at 1, 3, 5, and 7 years after transplant) were compared between the 2 groups.

Results—

Early vascular complications were more common ( P = .02) in multiple artery graft recipients (18.6%) than in single artery graft recipients (7.9%), mainly because of occlusion of a polar artery in grafts with multiple renal arteries (7.1%). Urologic complications were no more frequent in one group than in the other (5.7% vs 5.3%; P = .89). The 2 groups did not differ significantly ( P = .33) in long-term graft survival, with a median follow-up of 9.05 years (range, 0.1–12.7 years). Mean (SD) for creatinine clearance (59.4 [22.6] vs 55.9 [20.3] mL/min; P = .47), proteinuria (0.77 [2.1] vs 0.4 [0.8] g/24 h; P = .19), and systolic blood pressure (133.6 [14.5] vs 133.7 [17.5] mm Hg; P = .85) did not differ significantly between the 2 groups 7 years after transplant.

Conclusions—

Kidney transplant with grafts containing multiple renal arteries rather than grafts with a single renal artery does not significantly influence patient and graft outcomes.

Imaging evaluation of kidney transplant recipients

Renal transplantation is nowadays accepted as the treatment of choice for patients with end-stage renal disease. However, despite progress in immunosuppression and surgical techniques, various complications still can occur. Complications vary from vascular disorders and urologic diseases to parenchymal and immunologically related complications. The clinician evaluating the recipient with graft dysfunction has the option of choosing among a variety of imaging modalities including ultrasonography, nuclear medicine, computed tomography, and magnetic resonance imaging to start or continue the diagnostic work-up. In this article, we discuss the evaluation of the kidney transplant recipient using these imaging procedures, emphasizing the clinical diagnostic utility and role of each modality.

Polar nephrectomy in a transplanted kidney: a case report

After renal transplantation, infarction of the lower pole may be observed. We report an unusual case of lower pole infarction and perforation of the lower calyx due to thrombosis of a lower polar artery. This was managed successfully with partial nephrectomy (nephron-sparing surgery).

Late caliceal fistula after kidney transplantation

Caliceal fistula is a rare urological complication that can occur usually shortly after kidney transplantation (KTx). The occlusion of the renal accessory artery with subsequent necrosis of the kidney pole is the most common cause of the fistula development. We report a case of a 57-year-old man with reconstruction of two accessory renal arteries by anastomosis to the side of the main artery during graft placement complicated by late caliceal fistula, managed surgically. Directly after KTx good kidney graft function (serum creatinine concentration 151 micromol/L) was observed. The patient noticed protuberance and pain in the kidney graft area 5 months later. Diagnostic imaging revealed moderate urostasis and liquid collection in the region of the lower graft pole. Administration of a contrast medium through the inserted drain visualized a fistula of a lower renal calyx and ureteric stenosis. Percutaneous drainage was applied with subsequent stop of diuresis through the urethral catheter. During the surgery, the resection of a lower kidney graft pole necrosis was performed, with the closure of caliceal fistula. Simultaneously double pigtail ureteric stent was inserted. After the next two months the pigtail catheter was removed, and neither urostasis in the kidney graft nor liquid collection in the perigraft area were observed. The exceptionality of the case is the late caliceal fistula occurrence. We may only speculate, why it happened 5 months after KTx. The thrombosis of stenosed accessory artery is the most probable cause.