Early Prediction of Graft Outcomes After Kidney Transplantation From Donors After Circulatory Death: Biomarkers and Transplantation Characteristics

Association of Oral Tobacco-Free Nicotine Delivery Product with Acute Renal Tubular Necrosis

Usage of novel non-tobacco oral nicotine delivery products (ONDPs) has been increasing among adolescents in the United States. It is presumed that they are less toxic than their tobacco-containing counterparts, but that has not been examined in controlled studies. Most of the studies have focused on non-renal manifestations of tobacco consumption via different means. The renal manifestations of non-tobacco ONDPs are not very well known, especially in immunocompromised patients. A 19-year-old male transplant recipient presented with flank pain and a few days' history of intake of ZYNR pouches. Immunosuppression was with tacrolimus, mycophenolate, and steroids. Baseline serum creatinine was 1.1-1.3 mg/dL. Laboratory evaluation showed elevated C-reactive protein, increased serum creatinine and blood urea nitrogen, leukocytosis, neutrophilia, and increased lactate dehydrogenase (LDH). Infectious disease work-up was negative. A kidney transplant biopsy showed severe acute tubular injury/necrosis (ATN) without evidence of rejection. Donor-specific antibodies were negative. Other etiologies of hemolysis were negative. He did not require renal replacement therapy. Kidney function and LDH improved gradually. The most recent follow-up eight months after presentation showed a serum creatinine level of 2.6 mg/dL with stable electrolytes, with eGFR of 35 mL/min/1.73 m2. Here, we describe a 19-year-old adolescent with a kidney transplant who sustained ATN leading to advanced chronic disease apparently following the usage of non-tobacco ONDP. Further larger studies are needed to study ATN as a possible renal manifestation of these next-generation products to raise awareness among the public.

Interpretation of LDH Values after Kidney Transplantation

Kidney transplantation is the gold-standard therapy for end-stage renal disease. However, in the early postoperative period following allograft kidney transplantation, insufficient graft function presents a diagnostic challenge to clinicians. Ischemic damage to the graft and/or an early autoimmune rejection may cause a decrease in function. Ischemic damage is a benign and transient condition, while acute immune rejection requires immediate therapy. A kidney graft ultrasound may produce a false negative result, and graft biopsy is invasive and slow to return results. Serum lactate dehydrogenase (LDH) is under examination as a possible tool for differential diagnosis between ischemic damage and immune rejection. Herein, we analyze the continuous lab results of four patients in the early post-transplantation period, showing patterns correlating with different clinical outcomes and prognoses. In our experience, a persistent elevated LDH accompanies ischemic damage. Immune rejection was, however, associated with a decrease in LDH. Hemodialysis was not a confounding factor, while packed red blood cell transfusion caused severe diagnostic problems.

(Cast2021) Oxygenated Hypothermic Machine Perfusion of Kidney Transplantation from Donors After Cardiac Death Due to Long-Term Low Blood Pressure and Hypoxia: The First Case Report of a Clinical Trial Using a New Japanese Perfusion System

BACKGROUND

Machine perfusion of marginal kidney grafts obtained from donors after cardiac death (DCD) has become a standard therapy worldwide. However, the use of grafts from DCD due to long-term low blood pressure is associated with a high incidence of primary graft nonfunction. Furthermore, the importance of oxygenation in machine perfusion remains unclear. We report the first case of a clinical trial of a kidney transplant obtained from a DCD using a Japanese oxygenated hypothermic perfusion system (CMX-08W, Chuo Seiko Co Ltd, Asahikawa, Japan).

PATIENTS AND METHODS

The donor was a 61-year-old man with amyotrophic lateral sclerosis. His SpO₂ decreased to 80% to 90%, his blood pressure remained consistently low for 4 hours and 30 minutes, and he suffered a cardiac arrest. Subsequently, we carried him to the operating room. The warm ischemic time was 12 minutes, and the cold ischemic time was 418 minutes. The recipient was a 58-year-old man who had been undergoing hemodialysis for 26 years. He was diagnosed with nephrosclerosis and multiple renal cysts. Oxygenated hypothermic machine perfusion was used on the kidney transplant obtained from the DCD.

RESULTS

The recipient gradually recovered and was withdrawn from hemodialysis therapy 14 days post transplantation. His renal function improved, and he was discharged on postoperative day 36. Currently, his renal function remains good (phosphocreatine, 1.7).

CONCLUSIONS

Oxygenated machine perfusion is used to preserve organs and determine if an organ is suitable for transplantation. This may provide the possibility of perfusion preservation and expand the criteria for cardiac arrest-associated renal transplantation.

Role of novel biomarkers in kidney transplantation

Clinical application of biomarkers is an integral component of transplant care. Clinicians and scientists alike are in search of better biomarkers than the current serologic (serum creatinine, donor-specific antibodies), urine-derived (urinalysis, urine protein), and histologic ones we now use. The science behind recent biomarker discovery spans across multiple molecular biologic disciplines, including transcriptomics, proteomics, and metabolomics. Innovative methodology and integration of basic and clinical approaches have allowed researchers to unearth molecular phenomena preceding clinical disease. Biomarkers can be classified in several ways. In this review, we have classified them via their origin and outcome: Primarily immunologic, i.e., representative of immune regulation and dysfunction and non-immunologic, pertaining to delayed graft function, cardiovascular events/mortality, infection, malignancy, post-transplant diabetes, graft, and patient survival. Novel biomarker uses to guide the diagnosis and management of transplant-related outcomes is a promising area of research. However, the use of biomarkers to predict outcomes after kidney transplantation is not well studied. In this review, we summarize the recent studies illustrating biomarker use and transplant outcomes.