The Long-Term Immunogenicity of mRNABNT162b Third Vaccine Dose in Solid Organ Transplant Recipients.

We investigated humoral and T-cell response to a SARS-CoV-2 mRNA vaccine in solid organ transplant recipients (SOT-Rs) and healthy donors (HDs) before (T0) and after two (T1) and twelve months (T2) since the third dose administration. SOT-Rs were stratified according to the transplanted organ and to the time elapsed since the transplant. In SOT-Rs, detectable levels of anti-S antibodies were observed in 44%, 81% and 88% at T0, T1 and T2, respectively. Conversely, anti-S antibody levels were detected in 100% of HD at all time points. Lower antibody titers were observed in SOT-Rs compared to HDs, even stratifying by transplanted organs and the time elapsed since transplant. Lower percentages of responding and polyfunctional T-cells were observed in SOT-Rs as well as in each subgroup of SOT-Rs compared to HDs. At both T0 and T1, in SOT-Rs, a predominance of one cytokine production shortly was observed. Conversely, at T2, a dynamic change in the T-cells subset distribution was observed, similar to what was observed in HDs. In SOT-Rs, the third dose increased the rate of seroconversion, although anti-S levels remained lower compared to HDs, and a qualitatively inferior T-cell response to vaccination was observed. Vaccine effectiveness in SOT-Rs is still suboptimal and might be improved by booster doses and prophylactic strategies.

Torque teno virus (TTV): A gentle spy virus of immune status, predictive marker of seroconversion to COVID-19 vaccine in kidney and lung transplant recipients.

To date, no comprehensive marker to monitor the immune status of patients is available. Given that Torque teno virus (TTV), a known human virome component, has previously been identified as a marker of immunocompetence, it was retrospectively investigated whether TTV viral load may also represent a marker of ability to develop antibody in response to COVID-19-BNT162B2 vaccine in solid organ transplant recipients (SOT). Specifically, 273 samples from 146 kidney and 26 lung transplant recipients after successive doses of vaccine were analyzed. An inverse correlation was observed within the TTV copy number and anti-Spike IgG antibody titer with a progressive decrease in viremia the further away from the transplant date. Analyzing the data obtained after the second dose, a significant difference in TTV copy number between responsive and nonresponsive patients was observed, considering a 5 log10 TTV copies/mL threshold to discriminate between the two groups. Moreover, for 86 patients followed in their response to the second and third vaccination doses a 6 log10 TTV copies/mL threshold was used to predict responsivity to the booster dose. Although further investigation is necessary, possibly extending the analysis to other patient categories, this study suggests that TTV can be used as a good marker of vaccine response in transplant patients.

Contrast Enhanced Ultrasound Compared with MRI and CT in the Evaluation of Post-Renal Transplant Complications.

Renal transplantation (RT) is the treatment of choice for end-stage renal disease, significantly improving patients' survival and quality of life. However, approximately 3-23% of patients encounter post-operative complications, and radiology plays a major role for their early detection and treatment or follow-up planning. CT and MRI are excellent imaging modalities to evaluate renal transplant post-operative course; nevertheless, they are both associated with a high cost and low accessibility, as well as some contraindications, making them not feasible for all patients. In particular, gadolinium-based contrast can lead to the rare condition of nephrogenic systemic fibrosis, and iodine-based contrast can lead to contrast-induced nephropathy (CIN). CT also exposes the patients who may require multiple examinations to ionizing radiation. Therefore, considering the overall advantages and disadvantages, contrast-enhanced ultrasound (CEUS) is presently considered an effective first-line imaging modality for post-operative early and long-term follow-up in RT, reducing the need for biopsies and providing adequate guidance for drainage procedures. Hence, this paper aims to review the updated knowledge on CEUS compared with CT and MRI for the evaluation of RT renal transplant complications; advantages, limitations, and possible recommendations are provided.

The role of hypothermic machine perfusion in selecting renal grafts with advanced histological score.

BACKGROUND: Few studies explored the role of hypothermic machine perfusion (HMP) in the sub-group of non-standard renal grafts with a biopsy-proven advanced histological impairment. This study aimed to investigate the role of HMP in grafts with a Karpinski Score >3 in terms of the need for dialysis, creatinine reduction ratio at day-7 (CRR7), and 3-year graft survival. METHODS: Twenty-three perfused grafts with Karpinski Score >3 evaluated between November 2017 and December 2018 were retrospectively analyzed and compared with a control group of 32 non-perfused grafts transplanted between January 2014 and October 2017. RESULTS: After transplantation, perfused grafts had fewer cases requiring dialysis (8.7% vs. 34.4%; p = 0.051), a better reduction in serum creatinine (median at 7 days: 2.2 vs. 4.3 mg/dl; p = 0.045), and shorter length of hospital stay (median 11 vs. 15 days; p = 0.01). Three-year death-censored graft survival was better in the perfused cases (91.3% vs. 77.0%; p = 0.16). In perfused grafts, initial renal resistance (RR) had the best predictive value for renal function recovery after the first week, as defined by CRR7 ≤ 70% (AUC = 0.83; p = 0.02). A cut-off value of 0.5 mm Hg/ml/min showed a sensitivity of 82.4%, a specificity of 83.3%, and diagnostic odds ratio = 23.4. After dividing the entire population into a Low-RR (n = 8) and a High-RR Group (n = 15), more cases with CRR7 ≤ 70% were reported in the latter group (86.7 vs. 13.3%; p = 0.03). CONCLUSION: HMP yielded promising results in kidneys with Karpinski Score >3. Initial RR should be of interest in selecting non-standard organs for single kidney transplantation even in impaired histology.

SARS-COV-2 vaccination with BNT162B2 in renal transplant patients: Risk factors for impaired response and immunological implications.

Solid organ transplant patients are at a higher risk for poor CoronaVirus Disease-2019 (COVID-19)-related outcomes and have been included as a priority group in the vaccination strategy worldwide. We assessed the safety and efficacy of a two-dose vaccination cycle with mRNA-based COVID-19 vaccine (BNT162b2) among 82 kidney transplant outpatients followed in our center in Rome, Italy. After a median of 43 post-vaccine days, a SARS-CoV-2 anti-Spike seroprevalence of 52.4% (n = 43/82) was observed. No impact of the vaccination on antibody-mediated rejection or graft function was observed, and no significant safety concerns were reported. Moreover, no de novo HLA-donor-specific antibodies (DSA) were detected during the follow-up period. Only one patient with pre-vaccination HLA-DSA did not experience an increased intensity of the existing HLA-DSA. During the follow-up, only one infection (mild COVID-19) was observed in a patient after receiving the first vaccine dose. According to the multivariable logistic regression analysis, lack of seroconversion after two-dose vaccination independently associated with patient age ≥60 years (OR = 4.50; P = .02) and use of anti-metabolite as an immunosuppressant drug (OR = 5.26; P = .004). Among younger patients not taking anti-metabolites, the seroconversion rate was high (92.9%). Further larger studies are needed to assess the best COVID-19 vaccination strategy in transplanted patients.

Total Pancreatectomy for Ampullary Adenocarcinoma in a 74-Year-Old Patient: Case Report and Literature Review.

Primary ampullary neoplasms have origin in the ampulla of Vater, an anatomical structure where the common bile duct and the pancreatic duct join together as a common channel. It represents <0.5% of all gastrointestinal cancers and approximately 7% of all periampullary cancers. The adenocarcinomas arising in this region originate from different epithelial cellular constituents present at the site, the histopathological classification encompass: intestinal type, pancreaticobiliary type, and mixed type. Pancreaticoduodenectomy is the treatment of choice when there is an overt or highly suspicious malignant behaviour. We present here the case of a 74-year-old male patient who presented to our department for further investigation of obstructive jaundice and a pancreatic mass associated with a six-month history of significant weight loss and mild epigastric pain. Eventually, a total splenopancreatectomy was performed given the extension of structural anomalies of the organ secondary to an ampullary adenocarcinoma.

Expected and Observed Glomerular Filtration Rates in Kidney Transplant Patients Converted to Once Daily Tacrolimus: 10 Years of Follow-up.

The decline of allograft kidney function in the long term remains a significant issue in renal transplantation, with drug nephrotoxicity and cardiovascular complications as important risk factors. Our study aimed to evaluate the estimated glomerular filtration rate (eGFR) trend and metabolic cardiovascular risk factors over 10 years in a cohort of kidney transplant (KT) recipients converted from twice-daily (TD) tacrolimus (Tac) to once-daily (OD)-Tac. We enrolled 55 consecutive KT recipients who had been at the outpatient clinic between 2009 and 2011. Thirty-seven reached the 10-year follow-up. We compared the observed eGFR with the expected eGFR trend described in KT-recipients and monitored blood pressure and metabolic cardiovascular risk factors. The observed eGFR remained stable throughout the complete follow-up (P = .188). The observed decline of eGFR was significantly lower compared with the expected decline for KT patients (P < .001). The blood pressure was maintained within target values. The monitoring of plasma glucose levels demonstrated the stability of median values (P = .686), as well as cholesterol level (P = .250), high-density lipoprotein (HDL) cholesterol (P = .294), and triglycerides (P = .592) throughout the follow-up. The monitoring of tacrolimus plasma level demonstrated that median trough levels remained constant (median values 4.4-5.5 ng/mL) throughout the entire follow-up period (P = .149). We suggest that the reasonable control of metabolic risk factors for cardiovascular disease over long-term follow-up may significantly contribute to the preservation of eGFR compared with the decline expected in KT recipients.

Viremia Negativization After BK Virus Infection in Kidney Transplantation: A National Bicentric Study.

BACKGROUND: BK virus (BKV) infection represents a potentially dreadful complication after kidney transplantation (KT). When BK viremia is detected, the best therapeutic approach remains not entirely clarified. Critical elements of BK viremia treatment are immunosuppression minimization and introduction of drugs like leflunomide, everolimus, and fluoroquinolones. The study aimed to analyze the results of the BK viremia management in 2 collaborative Italian centers. METHODS: Ten patients undergoing KT in the 2 collaborative Italian centers of Sapienza University of Rome and University of L'Aquila from January 2013 to December 2017 and showing a post-KT diagnosis of BK viremia were retrospectively investigated. RESULTS: Mean time from KT to BKV positivity was 7 months (range: 1-19 months). At diagnosis, the mean viral load was 683,842 copies/mL (range: 5800-4,052,415 copies/mL), with an average zenith of 2,428,410 copies/mL (range: 6762-18,022,500 copies/mL). In the 5 patients with BKV nephropathy, we observed a switch from antimetabolite to leflunomide (n = 5), a switch from tacrolimus to everolimus (n = 3), or an introduction of fluoroquinolones (n = 3). BKV clearance was achieved in 3 patients. CONCLUSIONS: Early BKV diagnosis and stepwise minimization of immunosuppression remain the first-line approach in patients with BK viremia. In the presence of BKV nephropathy, a combination of antiviral drugs like leflunomide and fluoroquinolones/everolimus should favor viremia clearance.

Collaterals management during pancreatoduodenectomy in patients with celiac axis stenosis: A systematic review of the literature.

BACKGROUND/OBJECTIVES: Celiac axis stenosis (CAS) represents an uncommon and typically innocuous condition. However, when a pancreatic resection is required, a high risk for upper abdominal organs ischemia is observed. In presence of collaterals, such a risk is minimized if their preservation is realized. The aim of the present study is to systematically review the literature with the intent to address the routine management of collateral arteries in the case of CAS patients requiring pancreatoduodenectomy. METHODS: A systematic search was done in accordance with the PRISMA guidelines, using "celiac axis stenosis" AND "pancreatoduodenectomy" as MeSH terms. Seventy-four articles were initially screened: eventually, 30 articles were identified (n = 87). RESULTS: The main cause of CAS was median arcuate ligament (MAL) (n = 31; 35.6%), followed by atherosclerosis (n = 20; 23.0%). CAS was occasionally discovered during the Whipple procedure in 15 (17.2%) cases. Typically, MAL was divided during surgery (n = 24/31; 77.4%). In the great majority of cases (n = 83; 95.4%), vascular abnormalities involved the pancreatoduodenal arteries (i.e., dilatation, arcade, channels, aneurysms). Collateral arteries were typically preserved, being divided or reconstructed in only 14 (16.1%) cases, respectively. Severe ischemic complications were reported in six (6.9%) patients, 20.0% of whom were reported in patients with preoperatively unknown CAS (p-value 0.06). CONCLUSIONS: A correct pre-operative evaluation of anatomical conditions as well as a correct surgical planning represent the paramount targets in CAS patients with arterial collaterals. Vascular flow must be always safeguarded preserving/reconstructing the collaterals or resolving the CAS, with the final intent to avoid dreadful intra- and post-operative complications.

Cerebral Lymphoma in a Kidney Transplant: A Case Report.

Posttransplant lymphoproliferative disorder is a serious complication during a solid-organ transplant. A 28-year-old Asiatic man developed a cerebral lesion that was considered an abscess, while undergoing a kidney transplant. The lesion diameter did not go down with antibiotic therapy, so he underwent a complete surgical mass excision. Pathology showed a B-cell lymphoma. The Epstein-Barr virus-DNA by polymerase chain reaction in plasma was negative. He began chemotherapy with methotrexate and rituximab, and radiation therapy. He had to be restarted on regular hemodialysis 1 year after surgery. Three years after receiving the diagnosis, he was alive and had not developed any other posttransplant lymphoproliferative disorder. This report presents case of a patient who developed primary central nervous system B-cell lymphoma, 2 years after undergoing a kidney transplant. A combination of chemotherapy and radiotherapy is the best option for treatment of brain posttransplant lymphoproliferative disorder.