SARS-CoV-2 Antibody Response in Patients Undergoing Kidney Transplantation

The response of the immune system to COVID-19 in end stage kidney disease patients who undergo kidney transplantation has yet to be described. We report data on 72 patients who underwent SARS-CoV-2 antibody testing both before and after kidney transplantation and were followed for a median of 186 days (range 83, 277). Of the 25 patients with a positive antibody test at the time of transplant, 17 (68%) remained positive after transplantation. Patients were significantly more likely to have a persistently positive test if they reported a symptomatic COVID-19 infection prior to transplant (p=0.01). SARS-CoV-2 IgG index values were measured in a subset of kidney transplant recipients and compared to wait -listed dialysis patients. These assays demonstrated a more significant decline in IgG (58% versus 14% p = 0.008) in transplant recipients when compared to dialysis patients tested during the same time period. Additional analysis of the quality of the immune response measuring the binding of SARS-CoV-2 antibodies to the receptor-binding domain (RBD binding), the antibody neutralizing capability, and the antibody avidity demonstrated a more pronounced effect when comparing pre-transplant values to post-induction therapy/post transplant values. The attenuated IgG response seen in transplant patients compared to dialysis patients after induction therapy requires further study. These data have important implications for post-transplant management of vaccinated dialysis patients.

Primary hyperoxaluria as an indication of liver and kidney transplantation: Case report and literature review

Primary Hyperoxaluria (PH) is a metabolic liver disease that results in oxalate overproduction that cannot be metabolized by the liver [1]. PH is caused by mutations in one of three genes that encode enzymes involved in glyoxylate metabolism. As oxalate is primarily excreted in the urine, the kidney is the prime target for oxalate deposition, which leads to end-stage kidney disease [2]. A patient named MN with Nephrocalcinosis (NC) was referred to the Children`s Memorial Health Institute of Warsaw in early childhood. The patient was diagnosed with PH type 1. PH type 1 is caused by mutations in a gene called AGXT that encodes alanine-glyoxylate aminotransferase. This enzyme is found in hepatic peroxisomes. It converts a compound called glyoxylate to the amino acid glycine [3]. In 02.12.1996, at the age of 13 the patient received a first kidney transplant from family member. In 16/09/1998 graftectomy was performed due to rapidly progressive kidney failure, nephrocalcinosis and infections. The patient had to return to hemodialysis after renal allograft loss. Also the patient was diagnosed with chronic HCV genotype 4 infection in 1998. In 08.11.2002, at the age of 19, the patient was qualified for a simultaneous liver and second kidney transplantation due to primary hyperoxaluria. The patient was treated with combination of: Daclizumab, steroid, tacrolimus, mycophenolate mofetil. Since October, 2015 the patient had been treating with combination of ombitasvir, paritaprevir, ribavirin and ritonavir. Hepatitis C Virus (HCV) was successfully eliminated. Patients with kidney failure from primary hyperoxaluria type 1 should not undergo kidney transplantation alone due to the very high risk of recurrence. Combined liver and kidney transplantation is the treatment of choice [4]. Keywords: Primary hyperoxaluria; kidney insufficiency; kidney transplantation; combined liver; kidney transplantation.

Impact of obesity on the evolution of outcomes in peritoneal dialysis patients

Background Some studies reveal that obesity is associated with a decrease in mortality in haemodialysis (HD) patients. However, few studies have addressed the association between body mass index (BMI) and peritoneal dialysis (PD) patients. Methods We performed this longitudinal, retrospective study to evaluate the impact of obesity on PD patients, using data from the Catalan Registry of Renal Patients from 2002 to 2015 (n = 1573). Obesity was defined as BMI ≥30; low weight: BMI <18.5; normal range: BMI = 18.5–24.99; and pre-obesity: BMI = 25–29.99 kg/m2. Variations in BMI were calculated during follow-up. The main outcomes evaluated were the technique and patient survival. Results Obesity was observed in 20% of patients starting PD. We did not find differences in sex or PD modality, with the obesity group being older (65.9% are ≥55 years versus 59% non-obese, P = 0.003) and presenting more diabetes mellitus and cardiovascular disease (CVD) (47.9% obese versus 25.1% non-obese and 41.7% versus 31.5%, respectively). We did not observe differences in haemoglobin, albumin and Kt/V in obese patients. Regarding peritonitis rate, we did not find any difference between groups, presenting more peritonitis patients on continuous ambulatory peritoneal dialysis and aged ≥65 years [sub-hazard ratio (SHR) = 1.75, P = 0.000 and SHR = 1.56, P = 0.009]. In relation to technique survival, we found higher transfer to HD in the obese group of patients in the univariate analysis, which was not confirmed in the multivariate analysis (SHR = 1.12, P = 0.4), and we did not find differences in mortality rate. In relation to being transplanted, the underweight group, elderly and patients with CVD or diabetic nephropathy presented less probability to undergo kidney transplantation (SHR = 0.65, 0.24, 0.5 and 0.54, P < 0.05). Obese patients did not present differences in survival with weight changes but in normal-weight patients, a gain of 7% of the basal weight during the first year had a protective effect on death risk (hazard ratio 0.6, P = 0.034). Conclusions Obese and non-obese patients starting on PD had similar outcomes.

Equal 3-Year Outcomes for Kidney Transplantation Alone in HCV-Positive Patients With Cirrhosis

Kidney transplantation alone in clinically compensated patients with cirrhosis is not well documented. Current guidelines list cirrhosis as a contraindication for kidney transplantation alone. This is an Institutional Review Board–approved retrospective study. We report our experience with a retrospective comparison between transplants in hepatitis C virus–positive (HCV+) patients without cirrhosis and HCV+ patients with cirrhosis. All of the patients were followed for at least a full 3-year period. All of the deaths and graft losses were recorded and analyzed using Kaplan-Meier methodology. One- and three-year cumulative patient survival rates for noncirrhotic patients were 91% and 82%, respectively. For cirrhotic patients, one- and three-year cumulative patient survival rates were 100% and 83%, respectively (P = NS). One- and three-year cumulative graft survival rates censored for death were 94% and 81%, and 95% and 82% for the noncirrhosis and cirrhosis groups, respectively (P = NS). Comparable patient and allograft survival rates were observed when standard kidney allograft recipients were analyzed separately. This study is the longest follow-up document in the literature showing that HCV+ clinically ompensated patients with cirrhosis may undergo kidney transplantation alone as a safe and viable practice.