The type of SARS-CoV-2 vaccine influences serological response in kidney transplant recipients.

Vaccination is a promising strategy to control the ongoing pandemic; however, solid organ recipients tend to develop a weaker immune response to vaccination. Anti-spike SARS-CoV-2 antibodies titers were measured 2-4 weeks post-vaccination completion in 131 KT patients without previous infection. Demographic, clinical, and laboratorial parameters were analyzed to identify which factors contributed to seroconversion. Factors that influenced seroconversion, that occurred in 76 patients (58%), were longer time post-transplant, immunosuppression without an antiproliferative drug and vaccination with mRNA vaccines. Patients who received mRNA vaccines had significantly higher rates of seroconversion compared with adenovirus vector vaccines (67% vs 33%, P < .001) and higher anti-spike IgG titers. These findings reinforce the need to discuss the vaccination strategy in this population, including a third dose with a mRNA vaccine.

Doppler ultrasound: a powerful tool for vascular access surveillance.

National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF KDOQI) guidelines recommend Doppler ultrasound (DU) for surveillance of vascular access (VA), but trials have not been unanimous about its benefit on VA patency. The aim of this study was to evaluate the accuracy of DU for patency, as well as to highlight additional data provided by this method. A transversal study was conducted to evaluate DU method in correlation with BTM using paired t-test and Pearson test. Ultrasonography evaluation was performed with a Siemens Acuson X150 Ultrasound device and BTM-Qa with the Blood Temperature Monitor BTM(®). Access blood flow (Qa) values were correlated with several factors by nonparametric tests. Fifty hemodialysis patients were included, with mean age of 64.5 ± 13.7 years; durations of hemodialysis and VA were 51.4 ± 47.3 and 47.6 ± 42.1 months, respectively. The mean difference between DU and BTM flows was 20.5 ml/minute (p 0.624). Pearson correlation was 0.851 (p < 0.001). DU-Qa values varied significantly with several factors: type of VA, reason for DU referral, the presence of artery stenosis, and the location and number of stenosis. BTM-Qa values only varied significantly with the presence and number of stenosis. Various silent abnormalities were detected with DU. DU provides accurate anatomic and hemodynamic data to further knowledge regarding the etiology of stenosis and other abnormalities that compromise VA well functioning.

Doppler ultrasound and calcification score: improving vascular access surveillance.

AIM: Vascular access (VA) dysfunction limits hemodialysis delivery, which increases morbidity and mortality. The most com mon cause of VA failure is thrombosis, due to flow limiting stenosis resulting from neointimal hyperplasia. This occurs not only due to hemodynamic factors but also by systemic ones related to vascular atherosclerosis, inflammation and calcification, which has developed a simple vascular calcification score (SVCS) predictor of vascular calcification and arterial stiffness. The NKF-K/DOQ recommends several diagnostic procedures for VA surveillance. Blood access flow (Qa) has predictive power for the detection of stenosis. Our aim was to evaluate the role of systemic factors, especially SCVS, on Qa. MATERIAL AND METHODS: Transversal study in 50 patients. Qa value was obtained with Blood Temperature Monitor and Doppler method. Pearson coefficient evaluated correlation between them. Clinical, lab and radiological variables were recorded and non-parametric tests evaluated how both Qa varied with them. RESULTS: Pearson's corelation between DU-Qa and TD-Qa was 0.851 (p-value <0.001). DU-Qa varied significantly with age (p = 0.012), VA type (p = 0.021), SCVS (p = 0.030), intra-access arterial pressure (p = 0.015) and time on dialysis (p = 0.002). BTM-Qa varied significantly with diabetes status (p = 0.027), age (p = 0.017), first VA status (p = 0.036), intra-access arterial pressure (p = 0.028) and dialysis time (p = 0.001). Nevertheless, gender, hypertensive status and analitical parameters did not change the flow values. CONCLUSION: Higher SVCS was associated only with lower DU-Qas, giving this method an advantage towards the indirect one. Additionally, a simple method like SVCS may be used to guide new surveillance recommendations accordingly to risk stratification.

Long-Term Complications After Nephrectomy for Living Donor Transplant.

BACKGROUND: Living donor kidney transplant represents the best treatment option for patients with end-stage kidney disease; however, it has been associated with possible risks to the donor. Our aim was to evaluate the impact of kidney donation in the donor's estimated glomerular filtration rate (eGFR), blood pressure, and proteinuria and related risk factors. PATIENTS AND METHODS: A single-center, retrospective study, including all living donors who underwent nephrectomy between January 2000 and December 2019, was performed. Demographic, clinical, and laboratory data were collected. Risk factors for a decrease in eGFR >30 mL/min/1.73 m2 one year after donation were assessed. RESULTS: Eighty-six donors were included with a mean age of 46.7 ± 9.07 years. The mean follow-up was 105.6 ± 65.4 months, and 35 patients (41%) had more than 10 years of follow-up. No significant difference was found in proteinuria or body mass index (P > .1) before and after the donation. The prevalence of hypertension was higher after kidney donation (9.3% vs 22.1%; P < .001). A mean reduction in the eGFR in the first year of 37 ± 12 mL/min/1.73 m2, followed by stabilization in the following years, was observed. The only variable that was significantly associated with a decline in GFR >30 mL/min/1.73 m2 was a lower predonation eGFR, with a cutoff value established at 100 mL/min/1.73 m2 for our sample. DISCUSSION: Living donor nephrectomy appears to be an acceptably safe intervention. Predonation eGFR influences the adaptative response after nephrectomy; however, other variables did not have an impact on long-term outcome in our population.

A Less Common Cause of Acute Hepatitis in Kidney Transplant Recipients: A Case Series.

BACKGROUND: Hepatitis E virus (HEV) is a cause of significant morbidity and mortality, representing an important global public health problem. Immunocompetent patients with acute hepatitis E can clear the infection spontaneously; however, in approximately two thirds of cases, immunosuppressed patients, such as kidney transplant (KT) recipients, fail to clear the HEV infection and develop chronic hepatitis. PATIENTS AND METHODS: We report 3 cases of HEV infection in KT patients. Two presented only with laboratory abnormalities and elevated liver enzymes, and 1 presented with symptomatic disease motivating hospital admission. None was able to clear the infection spontaneously, and they were all treated with ribavirin, accompanied with reduction of immunosuppressive drugs. Adverse effects of the treatment were reported in 2 patients, and in 1 case, a dose reduction was necessary. All patients responded to the treatment and have no current evidence of active disease. No alterations of basal kidney function during or related to the treatment were registered. DISCUSSION: HEV screening in KT patients presenting with abnormal liver function of undetermined cause is fundamental, as it might have poorer outcomes in this specific population. The treatment with ribavirin seems to be safe and effective, although we must always be alert to potential side effects, maintaining a close follow-up of these patients.

Does pre- and post-angioplasty Doppler ultrasound evaluation help in predicting vascular access outcome?

BACKGROUND: Kidney Disease - Improving Global Outcomes (KDIGO) recommends post-percutaneous transluminal angioplasty (PTA) <30% residual stenosis (RS) and hemodynamic parameters improvement. Primary end point: how post-PTA access blood flow (ABF) improvement predicts vascular access (VA) outcome. Secondary: compare Doppler ultrasound (DU) and angiography diagnostic accuracy; determine how other factors predict outcome. METHODS: Eighty patients. DU evaluation performed pre- and post-PTA. Several parameters recorded. Secondary patency verified after 6 months. RESULTS: Initial ABF 537 ± 248 mL/min; final ABF 1013 ± 354 mL/min. Number and location of stenosis was highly correlated between DU and angiography (p<0.001); central vessels mismatching. First semester overall survival was 63%; significantly better for fistulas (76%) than grafts (51.7%), p 0.044. Final RS>30% associated to better survival, p 0.038. Initial ABF<500 mL/min and multiple stenosis did not affect outcome (p>0.05). A >2-fold ABF increase had no significant impact on fistulas (p>0.05) but was significantly associated with worst outcomes in grafts (23.1% vs. 73.5%, p 0.009). Grafts had lower survival (HR 3.3, p 0.034). CONCLUSIONS: Although less accurate for central lesions, DU has a key role on VA surveillance, allowing a morphologic and hemodynamic assessment. Angioplasty is effective in preserving VA; however, it may increase restenosis due to accelerated neointimal hyperplasia. Current parameters are not useful. Trials addressing this issue are needed.

Acute kidney injury by cantharidin poisoning following a silly bet on an ugly beetle.

Cantharidin is a poisonous substance secreted by blister beetles, including the 'Spanish fly'. Historically, cantharidin was used as an aphrodisiac, vesicant and abortifacient. Symptoms of poisoning include gastrointestinal and genitourinary mucosal irritation along with renal dysfunction. We present the case of a reckless 23-year-old soldier who accepted the challenge of eating a beetle (Berberomeloe majalis). Six hours later he was admitted to the emergency room with abdominal pain, dysuria, gross haematuria with clots, hypotension, fever and renal insufficiency. With intravenous fluid therapy, he recovered clinically. Laboratory parameters returned to normal within 1 week.

Random spot urine protein/creatinine ratio: a reliable method for monitoring lupus nephritis?

BACKGROUND: Lupus nephritis (LN) is a common and severe manifestation of systemic lupus erythematosus (SLE) that can lead to end-stage renal disease. According to the Kidney Disease Outcomes Global Improving clinical Guidelines for Glomerulonephritis, spot urine protein/creatinine (P/C) ratio should be used for monitoring LN. However, some reports write that the random spot urine P/C ratio is unreliable in monitoring proteinuria in SLE glomerulonephritis patients. The aim of this study was to evaluate the agreement of these two assay methods. METHODS: The prospective observational study was performed. Fifty-three paired (total 106) spot and 24-h urine collections were evaluated. STATISTICAL ANALYSIS: SPSS 20.0. RESULTS: Paired samples t-test did not reveal significant differences between the two-paired assay methods (spot P/C ratio versus 24-h proteinuria and 24-h P/C ratio) and a statistically significant correlation was observed between them: Pearson's coefficient of 0.847 (P < 0.001) and 0.863 (P < 0.001), respectively. However, after stratifying by degrees of proteinuria, a poor correlation was found in the range of <500 mg/day and only 26.6% of 24-h P/C ratio was explained by the spot P/C ratio. Adding to this, for proteinuria range between 500 and 1000 mg/day, there was no correlation (Pearson's -0.098; P > 0.05). In fact, only 1% of 24-h measurements could be explained by the spot P/C ratio. CONCLUSIONS: Our study demonstrated a good correlation between 24-h proteinuria and random P/C ratio among patients with LN. However, this correlation was poor for proteinuria under 500 mg/day and did not exist in a range between 500 and 1000 mg/day. This finding is of greater importance because this range is quite common in patients with LN remission. Until further clarification, to the best of our knowledge, we maintain reluctant to completely substitute the 24-h collection by the P/C ratio especially when a renal flare is suspected, or before any change in therapy.