Development of transplant renal artery thrombosis and signs of haemolytic-uraemic syndrome following the change from cyclosporin to tacrolimus in a renal transplant patient

Imaging of Renal Transplant Complications throughout the Life of the Allograft: Comprehensive Multimodality Review

The kidney is the most commonly transplanted solid organ. Advances in surgical techniques, immunosuppression regimens, surveillance imaging, and histopathologic diagnosis of rejection have allowed prolonged graft survival times. However, the demand for kidneys continues to outgrow the available supply, and there are efforts to increase use of donor kidneys with moderate- or high-risk profiles. This highlights the importance of evaluating the renal transplant patient in the context of both donor and recipient risk factors. Radiologists play an integral role within the multidisciplinary team in care of the transplant patient at every stage of the transplant process. In the immediate postoperative period, duplex US is the modality of choice for evaluating the renal allograft. It is useful for establishing a baseline examination for comparison at future surveillance imaging. In the setting of allograft dysfunction, advanced imaging techniques including MRI or contrast-enhanced US may be useful for providing a more specific diagnosis and excluding nonrejection causes of renal dysfunction. When a pathologic diagnosis is deemed necessary to guide therapy, US-guided biopsy is a relatively low-risk, safe procedure. The range of complications of renal transplantation can be organized temporally in relation to the time since surgery and/or according to disease categories, including immunologic (rejection), surgical or iatrogenic, vascular, urinary, infectious, and neoplastic complications. The unique heterotopic location of the renal allograft in the iliac fossa predisposes it to a specific set of complications. As imaging features of infection or malignancy may be nonspecific, awareness of the patient's risk profile and time since transplantation can be used to assign the probability of a certain diagnosis and thus guide more specific diagnostic workup. It is critical to understand variations in vascular anatomy, surgical technique, and independent donor and recipient risk factors to make an accurate diagnosis and initiate appropriate treatment.^©RSNA, 2019.

Treatment Options in Patients Suffering from Hemolytic-Uremic Syndrome: the Serbian Military Medical Academy Experience

Hemolytic-Uremic Syndrome (HUS) is a clinical syndrome with a triad of non-immune Microangiopathic Hemolytic Anemia (MAHA), thrombocytopenia and renal failure. Together with the Thrombotic Thrombocytopenic Purpura (TTP), it belongs to a group of diseases characterized as the Thrombotic Microangiopathy (TMA), which represents a microvascular occlusive disorder with the formation of a predominantly thrombocytic thrombus in the renal and/or systemic circulation. In the period starting from 2001 to 2017, 14 patients with a HUS were diagnosed at the Clinic for Nephrology (unfortunately ADAMTS 13 could not have been done due to technical reasons). In a retrospective clinical laboratory analysis and monitoring, we obtained the following results. Out of 14 patients, 10 were female (or 71.43%) and 4 were male (28.57%), the youngest patient was aged 17 and the oldest one 78, the average age of our patients was 55.33 years, the annual number of patients with the diagnosis of HUS was 0.93 patients per year, or 0.00116 in relation to the total number of patients treated. After monitoring the patients individually for the period ranging from 1 to 14 years, a stable remission was achieved in 5 patients, while a chronic renal insufficiency occurred in 3 patients. In two of our patients, a percutaneous kidney biopsy was performed with pathohistological findings described in references. Having done this retrospective analysis, we can conclude that the survival and complications of this rare, but serious disease correspond to the available world data.

Acute thrombosis of a transplanted renal artery after gastric ulcer bleeding in a patient with a long-term well-functioning renal allograft: A case report and literature review

BACKGROUND

Acute thrombosis of a transplanted renal artery is a serious vascular complication following renal allograft transplantation, which usually occurs within the first month after transplantation and often results in graft loss. It rarely occurs beyond the first month, except in a rejected kidney or in a kidney with high-grade transplant renal artery stenosis.

RESULT

A 65-year-old male with a history of type 2 diabetes mellitus, hypertension, pulmonary tuberculosis, and end-stage renal disease was previously treated with hemodialysis (HD). He received a kidney transplant and had a well-functioning graft for 2 years. He presented to our emergency department with gastric ulcer bleeding and received treatment involving an endoscopic submucosal epinephrine injection, a proton pump inhibitor, and blood transfusions. Nine days later, he complained of sudden lower abdominal pain and had acute anuric kidney failure. Renal ultrasonography revealed an absence of blood flow to the allograft kidney. Renal artery angiogram demonstrated complete occlusion of the transplanted renal artery. After thrombectomy and percutaneous transluminal angioplasty (PTA) with stent placement, 60% stenosis of the proximal renal artery with distal perfusion was noted. However, his graft function did not improve, and he received HD again. Histopathology of the transplanted kidney revealed ischemic tubular nephropathy with focal infarction without rejection.

CONCLUSION

This is the first case of acute thrombosis of the transplanted renal artery following gastric ulcer bleeding in a patient with a long-term well-functioning graft kidney.