Transplanting horseshoe kidneys: a worldwide survey

En bloc transplantation of horseshoe kidney in Korea

Transplantation of the horseshoe kidney can be performed en bloc or split into 2 grafts according to the vascular anomaly and the existence of the urinary collecting system in isthmus. From 2011 to 2014, there were 3 horseshoe kidney transplantations in Korea and transplantations were performed at 2 different centers. The transplantations were carried out successfully for all recipients without complications. All recipients have shown good graft kidney function after transplantation. No severe complication was revealed during follow-up period. We described the surgical technique used in the en bloc method to overcome various vascular anomalies and difficulties in choosing cannulation site and postoperative complications. En bloc transplantation of a horseshoe kidney is a useful strategy for patients with end-stage renal disease, and can provide favorable outcomes compared to the transplantation of a normal kidney.

Transplantation of Horseshoe Kidney from Living, Genetically Unrelated Donor

We report a case of renal transplantation using a horseshoe kidney from a living, genetically unrelated donor. The recipient was a 60-year-old man with diabetic nephropathy, and the donor was the 63-year-old wife of the recipient with a horseshoe kidney free of complications. Computed tomography showed two renal arteries and one renal vein on the left side, and the isthmus was perfused by several accessory arteries and veins. To demarcate the boundary of the isthmus, the left renal artery was ligated and cannulated for in situ perfusion. Furthermore, the isthmus was clamped, and the boundary of the isthmus was confirmed. The kidney was divided at the left margin of the perfused boundary. The cut ends of the isthmus were closed by sutures. The left kidney was transplanted into the right iliac fossa of the recipient. Asymptomatic fluid collection occurred on the cut surface at the isthmus of the donor, and this fluid decreased in due course. On the other hand, the recipient experienced no surgical complication or rejection, while maintaining serum creatinine levels of 2.00–2.20 mg/dL over a 22-month follow-up period. Horseshoe kidneys may be used for transplantation in selected cases after a detailed preoperative evaluation.

Horseshoe kidney transplantation

Horseshoe kidney is a fusion anomaly found in approximately one in 400-600 people. Due to vascular and ureteral variations, transplantation with a horseshoe kidney presents a technical challenge. In our case, the isthmus connected the upper poles and contained parenchyma. It consisted of three renal arteries, five veins collected to the inferior vena cava, and two ureters and pyelons. It was implanted en bloc to the left side retroperitoneally. During the early period, cellular and humoral rejection was confirmed and treated. For a urine leak, double J catheters were implanted into both ureters. Later, the first catheter was removed. Subsequently, urinary sepsis developed, necessitating graftectomy. The uncommon anatomy of ureters and antibody-mediated rejection (AMR) may both be factors for a ureter tip necrosis led to an infected urinoma. After other Hungarian authors, we also report a horseshoe kidney transplantation that was technically successful. However, after an adequately treated but severe acute humoral rejection, the patient developed sepsis, and the kidney had to be removed. We conclude that transplantation with horseshoe kidney is technically feasible but may increase the risk for urinary complications and resultant infections. Careful consideration of risk and benefit is advised when a transplant professional is faced with this option.

Contrast imaging study of the horseshoe kidney for transplantation

In the surgical setting, horseshoe kidneys (HKs) may be a cause for confusion because of their complicated morphology, especially in the vicinity of the vascular and urinary collecting systems around the isthmus of the HK. In the patients with HK, analysis of the anatomical structure of the isthmus is both useful and necessary. The aim of this study is to observe the vascular and collecting system of the HK using anatomical and contrast imaging technique, then make use of the knowledge for clinical anatomy. A HK voluntarily donated post-mortem to our department in 2013 by an 80-year-old woman was dissected. The gross anatomy of this HK was reported. In this study, we additionally analyzed this kidney using micro-computed tomography with both colored and colorless contrast media after the kidney was made transparent. Contrast imaging clearly revealed that each of the five renal arteries, including the three surplus renal arteries, entering the HK distributed blood to different regions. Neither side of the urinary collecting system crossed the midline of the isthmus. Two surplus renal veins emerged from the HK and two ureters descended dorsal to the isthmus. These observations show that gross anatomical observation and contrast imaging of the HK can provide very important surgical information. Our results can contribute to both better understanding of fundamental knowledge and progress in the surgery of HKs such as in the setting of biopsy and transplantation.

Transplantation of a horseshoe kidney found during harvest operation of a cadaveric donor: a case report

A 34-yr-old female was diagnosed as being brain dead. Preoperative ultrasound revealed no abnormal focal lesions. However, the horseshoe kidney was identified during organ harvest. En bloc nephrectomy was performed. The kidney was divided at the midline of isthmus. The divided right kidney was discarded due to numerous arteries and veins. The divided left kidney was transplanted. After declamping, the kidney was well perfused and started clearing. Resistive index was 0.72. Glomerular filtration ratio was 84.69 mL/min on postoperative day 14. The horseshoe kidney can be successfully transplanted and could be a good solution for the shortage of organ donors.

Segmental Renal Ischemia following Transplantation of Horseshoe Kidney as Separate Allografts

Introduction. Horseshoe kidney is a congenital anomaly that presents unique challenges for the transplant surgeon. The mere presence of horseshoe kidney should not preclude consideration for transplantation. Case Report. A 33-year-old women suffering from end-stage renal disease underwent deceased donor renal transplant with a divided horseshoe kidney. We present a postoperative complication and the technical strategy for transplant salvage. The patient currently has excellent graft function. Discussion. Horseshoe kidneys do present challenges for successful transplantation. Though case reports of successful transplantation are increasing, we present a technical complication and successful transplant salvage strategy. Technical descriptions in the literature of successful back-table preparation strategies should help more transplant surgeons to begin to utilize this resource. Conclusion. This study concludes that horseshoe kidneys can be successfully used for transplantation and provides a technical strategy to salvage the transplant after a unique complication associated with these donor kidneys.

Aortic Extension for En Bloc Transplantation of Horseshoe Kidneys

INTRODUCTION

We report a technique for extending the distal aorta to facilitate the transplantation of en bloc horseshoe kidneys.

TECHNICAL CONSIDERATIONS

En bloc horseshoe kidneys can be transplanted by a technique that is analogous to the en bloc transplantation of small pediatric kidneys. However, the horseshoe kidney's isthmus prevents ascent of the kidney, and the fused lower poles stay below the level of the inferior mesenteric artery. Therefore, the distal aorta is behind the isthmus. Extending the distal aorta produces adequate vessel length to simplify en bloc transplantation of horseshoe kidneys. The extra aortic length is obtained by spatulating the distal common iliac arteries on their medial surfaces and bringing them together as a "pair of pants" for about 1.5 cm. This produces an arterial conduit that branches into the left and right common iliac arteries and then rejoins at the distal aorta. The aortic extension produces a useable vascular conduit that can be anastomosed to the recipient's external iliac artery. The distal inferior vena cava is anastomosed to the external iliac vein. We used this technique in 1 patient. The transplanted kidney made urine promptly and was providing normal function with a serum creatinine of 1.1 mg/dL.

CONCLUSIONS

It is preferable to transplant some horseshoe kidneys en bloc using the distal aorta and inferior vena cava for vascular anastomoses. This technique extends the distal aorta and provides adequate vessel length to facilitate en bloc transplantation.

Split technique in horseshoe kidney transplantation

BACKGROUND/AIMS

Nowadays, owing to a greater number of patients waiting for a kidney donation and to a shortage of organs donated, more suitable organ acceptance criteria have been formulated. Horseshoe kidney transplantations have become feasible giving good allograft outcomes. The aim of this paper is to illustrate the split technique in horseshoe kidney transplantation and to report long-term results.

METHODS

During the period from February 2004 to February 2005, two horseshoe kidneys were harvested from multiple organ retrieval. The surgical features and outcomes of these 2 cases are described separately. Mean follow-up time was 12.3 months.

CONCLUSIONS

Organs that were previously said to be marginal are being used more regularly and the more suitable selection does not exclude elderly donors with or without underlying diseases. Horseshoe kidney transplantation requires greater skills and experience of the surgeons compared to conventional kidney transplantation. This kind of renal abnormality has to be considered a feasible option for transplantation. Good long-term results are reported.

Horseshoe kidney transplantation

Even though the number of patients awaiting renal transplant is rapidly increasing, the donor pool remains relatively stable. In an attempt to increase this pool, marginal kidneys and kidneys with congenital anatomical variations are being used. Horseshoe kidneys, being the most common renal fusion anomaly, can provide a useful solution to the ever-increasing gap between demand and supply. These kidneys have been successfully transplanted en bloc into a single recipient or, alternatively they have been divided and transplanted into 2 recipients. We report a case of the successful transplantation of an en bloc horseshoe kidney into a single recipient. To the best of our knowledge this is the first of its kind in the U.K. The relevant literature is also reviewed with the aim of raising awareness about the necessity and promising outcomes of such transplants.