In vitro and in vivo evidence that the switch from calcineurin to mTOR inhibitors may be a strategy for immunosuppression in Epstein-Barr virus-associated post-transplant lymphoproliferative disorder.

Post-transplant lymphoproliferative disorder is a life-threatening complication of immunosuppression following transplantation mediated by failure of T cells to control Epstein-Barr virus (EBV)-infected and transformed B cells. Typically, a modification or reduction of immunosuppression is recommended, but insufficiently defined thus far. In order to help delineate this, we characterized EBV-antigen-specific T cells and lymphoblastoid cell lines from healthy donors and in patients with a kidney transplant in the absence or presence of the standard immunosuppressants tacrolimus, cyclosporin A, prednisolone, rapamycin, and mycophenolic acid. Phenotypes of lymphoblastoid cell-lines and T cells, T cell-receptor-repertoire diversity, and T-cell reactivity upon co-culture with autologous lymphoblastoid cell lines were analyzed. Rapamycin and mycophenolic acid inhibited lymphoblastoid cell-line proliferation. T cells treated with prednisolone and rapamycin showed nearly normal cytokine production. Proliferation and the viability of T cells were decreased by mycophenolic acid, while tacrolimus and cyclosporin A were strong suppressors of T-cell function including their killing activity. Overall, our study provides a basis for the clinical decision for the modification and reduction of immunosuppression and adds information to the complex balance of maintaining anti-viral immunity while preventing acute rejection. Thus, an immunosuppressive regime based on mTOR inhibition and reduced or withdrawn calcineurin inhibitors could be a promising strategy for patients with increased risk of or manifested EBV-associated post-transplant lymphoproliferative disorder.

[Pancreas transplantation-clinic, technique, and histological assessment]. / Pankreastransplantation ­ Klinik, Technik und histologische Beurteilung.

BACKGROUND: In Germany pancreas transplants are performed in only a few selected and specialized centres, usually combined with a kidney transplant. Knowlegde of the indications for and techniques of transplantation as well as of the histopathological assessment for rejection in pancreas and duodenal biopsies is not very widespread. AIM: To give an overview of the development and status quo in pancreas-kidney-transplantation in Germany summarizing the experience of the largest German pancreas transplant centre and to give a résumé of the results of histological diagnoses of biopsy specimens submitted between 06/2017 and 12/2020. Moreover, a detailed description and illustration of histological findings is included. MATERIAL AND METHODS: A thorough literature search for aspects of the history, technique and indication for pancreas transplantation was performed and discussed in the context of the local experience and technical particularities specific for the transplant centre in Bochum. The occurrence of complications was compared with international reports. Results of pancreas and duodenal biopsies submitted to Erlangen between 06/2017 and 12/2020 for histological evaluation, which were evaluated according to the Banff classification, were summarized. For a better understanding key histological findings of pancreas rejection and differential diagnoses were illustrated and discussed. RESULTS: A total of 93 pancreas transplant specimens and 3 duodenal biopsies were included. 34.4% of pancreas specimens did not contain representative material for a diagnosis. In the remaining 61 biopsies 24.6% showed no rejection, 62.3% were diagnosed with acute T-cell mediated rejection (TCMR) and 8.2% with signs suspicious of antibody-mediated rejection (ABMR). Acute acinary epithelial injury was seen in 59%, pancreatitis in 8.2% and allograft fibrosis was reported in as many as 54.1%. Calcineurin-inhibitor toxicity was discussed in only 4.9%. CONCLUSION: Pancreas-kidney-transplantation and standardized histological assessment of the transplanted pancreas or rarely duodenum with reporting according to the updated Banff classification of pancreas transplants or previous reports of duodenal rejection are important mainstays in the management of patients with diabetes.

Immune monitoring facilitates the clinical decision in multifocal COVID-19 of a pancreas-kidney transplant patient.

The optimal management in transplant recipients with coronavirus disease 2019 (COVID-19) remains uncertain. The main concern is the ability of immunosuppressed patients to generate sufficient immunity for antiviral protection. Here, we report on immune monitoring facilitating a successful outcome of severe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated pneumonia, meningoencephalitis, gastroenteritis, and acute kidney and pancreas graft failure in a pancreas-kidney transplant recipient. Despite the very low numbers of circulating B, NK, and T cells identified in follow-up, a strong SARS-CoV-2 reactive T cell response was observed. Importantly, we detected T cells reactive to Spike, Membrane, and Nucleocapsid proteins of SARS-CoV-2 with majority of T cells showing polyfunctional proinflammatory Th1 phenotype at all analyzed time points. Antibodies against Spike protein were also detected with increasing titers in follow-up. Neutralization tests confirmed their antiviral protection. A correlation between cellular and humoral immunity was observed underscoring the specificity of demonstrated data. We conclude that analyzing the kinetics of nonspecific and SARS-CoV-2-reactive cellular and humoral immunity can facilitate the clinical decision on immunosuppression adjustment and allow successful outcome as demonstrated in the current clinical case. Although the antiviral protection of the detected SARS-CoV-2-reactive T cells requires further evaluation, our data prove an ability mounting a strong SARS-CoV-2-reactive T cell response with functional capacity in immunosuppressed patients.

Allograft infiltration and meningoencephalitis by SARS-CoV-2 in a pancreas-kidney transplant recipient.

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) preferentially affects epithelia of the upper and lower respiratory tract. Thus, impairment of kidney function has been primarily attributed until now to secondary effects such as cytokine release or fluid balance disturbances. We provide evidence that SARS-CoV-2 can directly infiltrate a kidney allograft. A 69-year-old male, who underwent pancreas-kidney transplantation 13 years previously, presented to our hospital with coronavirus disease 2019 (COVID-19) pneumonia and impaired pancreas and kidney allograft function. Kidney biopsy was performed showing tubular damage and an interstitial mononuclear cell infiltrate. Reverse transcriptase polymerase chain reaction from the biopsy specimen was positive for SARS-CoV-2. In-situ hybridization revealed SARS-CoV-2 RNA in tubular cells and the interstitium. Subsequently, he had 2 convulsive seizures. Magnetic resonance tomography suggested meningoencephalitis, which was confirmed by SARS-CoV-2 RNA transcripts in the cerebrospinal fluid. The patient had COVID-19 pneumonia, meningoencephalitis, and nephritis. SARS-CoV-2 binds to its target cells through angiotensin-converting enzyme 2, which is expressed in a broad variety of tissues including the lung, brain, and kidney. SARS-CoV-2 thereby shares features with other human coronaviruses including SARS-CoV that were identified as pathogens beyond the respiratory tract as well. The present case should provide awareness that extrapulmonary symptoms in COVID-19 may be attributable to viral infiltration of diverse organs.

Stability of 12 T-helper cell-associated cytokines in human serum under different pre-analytical conditions.

Cytokines are soluble and readily analyzed signaling molecules which reveal vital cues about the state of the immune system. As such, they serve in diagnosis and monitoring of immune-related disorders, where strictly controlled handling of the samples including storage and freeze/thawing procedures are required. In basic research and clinical trials, human serum samples can be left for long-term storage before processing. Storage space is commonly limited in scientific laboratories, which require storage of fewer but larger aliquots of patient serum samples. There are also practical limitations to the number of analytes to be processed at the same time. Further, new findings and technological progress might prompt analysis of hitherto unconsidered or undetectable molecules. Repeated freeze/thawing of serum samples is therefore a likely scenario, raising the question of the stability of the measured analytes under such conditions. To address this question, we subjected serum samples with spiked-in T-helper cell associated cytokines to several cycles of freeze/thawing under different conditions, including storage at -20 °C or -80 °C and thawing at 4 °C, 22 °C, and 37 °C, respectively. The concentration of TNF-α, IL-4, IL-17F, and IL-22 decreased after storage at room temperature for 4 h before freezing. Generally, storage at -20 °C resulted in reduced cytokine concentrations. This contrasts storage at -80 °C, which gave stable analyte concentrations; unaffected by repeated freeze/thaw cycles. The study presented here highlights the need for sentinel samples with known cytokine concentrations as internal control for the freeze/thaw process.

Impact of donor cardiopulmonary resuscitation on the outcome of simultaneous pancreas-kidney transplantation-a retrospective study.

Previous cardiac arrest in brain-dead donors has been discussed as a potential risk factor in pancreas transplantation (PT), leading to a higher rate of organ refusal. This study aimed to assess the impact of cardiopulmonary resuscitation (CPR) in brain-dead donors on pancreas transplant outcome. A total of 518 type 1 diabetics underwent primary simultaneous pancreas-kidney (SPK) transplantation at our center between 1994 and 2018. Patients were divided into groups, depending on whether their donor had been resuscitated or not. A total of 91 (17.6%) post-CPR donors had been accepted for transplantation (mean duration of cardiac arrest, 19.4 ± 15.6 min). Those donors were younger (P < 0.001), had lower pancreas donor risk index (PDRI, P = 0.003), and had higher serum creatinine levels (P = 0.021). With a median follow-up of 167 months (IQR 82-229), both groups demonstrated comparable short- and long-term patient and graft survival. The resuscitation time (<20 min vs. ≥20 min) also showed no impact, with similar survival rates for both groups. A multivariable Cox regression analysis suggested no statistically significant association between donor CPR and patient or graft survival. Our results indicate that post-CPR brain-dead donors are suitable for PT without increasing the risk of complications.

Should kidney allografts from old donors be allocated only to old recipients?

In several deceased donor kidney allocation systems, organs from elderly donors are allocated primarily to elderly recipients. The Eurotransplant Senior Program (ESP) was implemented in 1999, and since then, especially in Europe, the use of organs from elderly donors has steadily increased. The proportion of ≥60-year-old donors reported to the Collaborative Transplant Study (CTS) by European centers has doubled, from 21% in 2000-2001 to 42% in 2016-2017. Therefore, in the era of organ shortage it is a matter of debate whether kidney organs from elderly donors should only be allocated to elderly recipients or whether <65-year-old recipients can also benefit from these generally as "marginal" categorized organs. To discuss this issue, a European Consensus Meeting was organized by the CTS on April 12, 2018, in Heidelberg, in which 36 experts participated. Based on available evidence, it was unanimously concluded that kidney organs from 65- to 74-year-old donors can also be allocated to 55- to 64-year-old recipients, especially if these organs are from donors with no history of hypertension, no increased creatinine, no cerebrovascular death, and no other reasons for defining a marginal donor, such as diabetes or cancer.

The impact of blood pressure variability and pulse pressure on graft survival and mortality after kidney transplantation.

BACKGROUND: Blood pressure variability and pulse pressure are strong and independent predictors of cardiovascular morbidity and mortality in the general population. So far, there are no data on the impact of blood pressure variability on mortality and graft survival after renal transplantation. METHODS: We performed a retrospective analysis of 877 patients who underwent kidney transplantation between 1997 and 2011 in two transplant centers in Germany (Berlin and Bochum) with a follow-up of 12-266 months. Visit-to-visit blood pressure variability over the first 12 months after transplantation (3 visits) and during the first 120 months after transplantation (7 visits) was calculated as the coefficient of variation (CV = standard deviation (SD)/mean blood pressure). Patient and graft survival was defined as composite endpoint. RESULTS: Cumulative survival was significantly higher for those patients with lower systolic blood pressure and pulse pressure within both the first 12 months and the 120 months posttransplant. After adjustment of data for gender, age, body mass index, and coronary artery disease, the cumulative incidence of the combined endpoint did not significantly differ between patients with lower vs higher CV (12 months CV hazard ratio (HR) (95% CI) = 0.90 (0.66-1.23), P = 0.51; 120 months CV HR (95% CI) = 0.92 (0.67-1.26), P = 0.60). A lower systolic blood pressure remained highly predictive for better survival in adjusted analyses. CONCLUSION: Visit-to-visit blood pressure variability is not associated with mortality or graft loss after kidney transplantation in this retrospective analysis. In analogy to the general population, however, there is an inverse relationship of survival and pulse pressure as a marker of arterial stiffness.

A Valine Mismatch at Position 129 of MICA Is an Independent Predictor of Cytomegalovirus Infection and Acute Kidney Rejection in Simultaneous Pancreas⁻Kidney Transplantation Recipients.

The polymorphic major histocompatibility complex class I chain-related molecule A (MICA) and its soluble form (sMICA) interact with activating receptor natural-killer group 2 member D (NKG2D) on natural-killer (NK) and T cells, thereby modifying immune responses to transplantation and infectious agents (e.g., cytomegalovirus). Two single-nucleotide polymorphisms (SNPs), rs2596538GA in the MICA promoter and rs1051792AG in the coding region (MICA-129Val/Met), influence MICA expression or binding to NKG2D, with MICA-129Met molecules showing higher receptor affinity. To investigate the impact of these SNPs on the occurrence of cytomegalovirus infection or acute rejection (AR) in individuals who underwent simultaneous pancreas⁻kidney transplantation (SPKT), 50 recipient-donor pairs were genotyped, and sMICA levels were measured during the first year post-transplantation. Recipients with a Val-mismatch (recipient Met/Met and donor Val/Met or Val/Val) showed shorter cytomegalovirus infection-free and shorter kidney AR-free survival. Additionally, Val mismatch was an independent predictor of cytomegalovirus infection and kidney AR in the first year post-transplantation. Interestingly, sMICA levels were lower in rs2596538AA and MICA129Met/Met-homozygous recipients. These results provide further evidence that genetic variants of MICA influence sMICA levels, and that Val mismatch at position 129 increases cytomegalovirus infection and kidney AR risk during the first year post-SPKT.

Rescue allocation and recipient oriented extended allocation in kidney transplantation-influence of the EUROTRANSPLANT allocation system on recipient selection and graft survival for initially nonaccepted organs.

Nonaccepted kidneys grafts enter the rescue allocation (RA) process to avoid discards. In December 2013, recipient oriented extended allocation (REAL) was introduced to improve transparency. The aim of this study was to evaluate the influence of REAL on recipients' selection and graft function compared to the formerly existing RA as well as to identify factors that influence graft outcome. Therefore, a multicenter study of 10 transplant centers in the same region in Germany was performed. All transplantations after RA or REAL from December 1, 2012, until December 31, 2014, with a follow-up time until December 31, 2015 were analyzed. 113 of 941 kidney transplantations were performed after RA or REAL (12%). With REAL, the number of refusals before transplantation had increased (12 ± 7.1 vs. 8.6 ± 8.6, P = 0.036), and cold ischemia time has decreased (13.6 ± 3.6 vs. 17.2 ± 4.8 h, P = 0.019). Recipients after REAL needed significantly more allocation points compared to RA to receive a kidney. One-year graft survival was comparable. If kidneys from the same donor were transplanted to two recipients at one center, the greater the difference in recipient age, the greater the difference in serum creatinine after 12 months (-0.019 mg/dl per year, P = 0.011) was, that is older recipients showed lower creatinine. REAL influences selection of the recipients compared to the former RA era for successful organ receipt. Graft function is comparable and seems to be influenced by recipient age.

High-urgency kidney transplantation in the Eurotransplant Kidney Allocation System: success or waste of organs? The Eurotransplant 15-year all-centre survey.

BACKGROUND: In the Eurotransplant Kidney Allocation System (ETKAS), transplant candidates can be considered for high-urgency (HU) status in case of life-threatening inability to undergo renal replacement therapy. Data on the outcomes of HU transplantation are sparse and the benefit is controversial. METHODS: We systematically analysed data from 898 ET HU kidney transplant recipients from 61 transplant centres between 1996 and 2010 and investigated the 5-year patient and graft outcomes and differences between relevant subgroups. RESULTS: Kidney recipients with an HU status were younger (median 43 versus 55 years) and spent less time on the waiting list compared with non-HU recipients (34 versus 54 months). They received grafts with significantly more mismatches (mean 3.79 versus 2.42; P < 0.001) and the percentage of retransplantations was remarkably higher (37.5 versus 16.7%). Patient survival (P = 0.0053) and death with a functioning graft (DwFG; P < 0.0001) after HU transplantation were significantly worse than in non-HU recipients, whereas graft outcome was comparable (P = 0.094). Analysis according to the different HU indications revealed that recipients listed HU because of an imminent lack of access for dialysis had a significantly worse patient survival (P = 0.0053) and DwFG (P = 0.0462) compared with recipients with psychological problems and suicidality because of dialysis. In addition, retransplantation had a negative impact on patient and graft outcome. CONCLUSIONS: Facing organ shortages, increasing wait times and considerable mortality on dialysis, we question the current policy of HU allocation and propose more restrictive criteria with regard to individuals with vascular complications or repeated retransplantations in order to support patients on the non-HU waiting list with a much better long-term prognosis.

125 Cases of duodenoduodenostomy in pancreas transplantation: a single-centre experience of an alternative enteric drainage.

Several exocrine drainage procedures have been successfully developed to perform pancreas transplantation (PT). Retroperitoneal graft placement allows exocrine drainage via direct duodenoduodenostomy (DD). This technique provides easy access for endoscopic surveillance and biopsy. A total of 241 PT procedures were performed in our centre between 2002 and 2012. DD was performed in 125 patients, and duodenojejunostomy (DJ) in 116 patients. We retrospectively compared our experience with these two types of enteric drainage, focusing on graft and patient survivals, as well as postoperative complications. With a mean follow-up of 59 months, both groups demonstrated comparable patient and graft survivals. 14 (11%) of 125 cases in the DD group and 21 (18%) of 116 cases in the DJ group had pancreatic graft loss (P = 0.142). Graft thrombosis [5 (4%) vs. 18 (16%) P = 0.002], anastomotic insufficiency [2 (1.6%) vs. 8 (7%) P = 0.052] and relaparotomy [52 (41%) vs. 56 (48%) P = 0.29] occurred more frequently in the DJ group, whereas gastrointestinal bleeding [14 (11%) vs. 4 (3%) P = 0.026] occurred more often in the DD group. DD is a feasible and safe technique in PT, with no increase in enteric complications. It is equivalent to other established techniques and extends the feasibility of anastomotic sites, especially in recipients who have undergone a second transplantation.

A rare cause of unilateral leg swelling: May-Thurner Syndrome.

Common left iliac vein compression, otherwise known as May-Thurner Syndrome (MTS), is a medical condition that refers to chronic compression of an anatomical variant of the left iliac vein by the overlying right common iliac artery and is a predisposing factor for deep vein thrombosis of the left lower limb (LDVT). Although MTS is not often, its true prevalence is underestimated due to misdiagnose, fact that can result to life-threatening conditions such as the development of LDVT and pulmonary embolism. In this paper, we present a case of MTS presenting at our department with unilateral leg swelling without LDTV that was treated through endovascular management along with long-term anticoagulation. With this presentation, the authors wish to emphasise the importance of MTS as a frequently under-diagnosed condition that needs to be ruled out in unilateral left leg swelling with or without LDVT.

Pneumoperitoneum: always a surgical case?

Spontaneous idiopathic pneumoperitoneum (SIP) is a rare condition in the surgical practice. We introduce a case of an alcoholic male who presented with nausea, vomiting and diarrhea without clinical signs of peritonitis. A computed tomography of the abdomen showed free air distributed mainly along the ascending colon. We performed an emergency laparoscopy, which revealed no signs of perforation or bowl ischemia but showed air bubbles in the mesentery along the ascending colon. Subsequent endoscopy revealed unclassified inflammatory bowel disease manifesting in the rectum, erythematous mucosa and epithelialized erosions of the stomach. The patient discharged himself on Day 8 after the surgery. The causes of SIP are unknown, but some authors assume microperforation. SIP can be a challenge for the choice of therapy. Laparoscopy may be particularly beneficial in patients with generalized peritonitis, while patients with moderate symptoms may benefit from conservative treatment.

Lasting response by vertical inhibition with cetuximab and trametinib in KRAS-mutated colorectal cancer patient-derived xenografts.

Although approximately half of all metastatic colorectal cancers (mCRCs) harbour mutations in KRAS or NRAS, hardly any progress has been made regarding targeted treatment for this group over the last few years. Here, we investigated the efficacy of vertical inhibition of the RAS-pathway by targeting epidermal growth factor receptor (EGFR) and mitogen-activated protein kinase kinase (MEK) in patient-derived xenograft (PDX) tumours with primary KRAS mutation. In total, 19 different PDX models comprising 127 tumours were tested. Responses were evaluated according to baseline tumour volume changes and graded as partial response (PR; ≤ - 30%), stable disease (SD; between -30% and +20%) or progressive disease (PD; ≥ + 20%). Vertical inhibition with trametinib and cetuximab induced SD or PR in 74% of analysed models, compared to 24% by monotherapy with trametinib. In cases of PR by vertical inhibition (47%), responses were lasting (as long as day 137), with a low incidence of secondary resistance (SR). Molecular analyses revealed that primary and SR was driven by transcriptional reprogramming activating the RAS pathway in a substantial fraction of tumours. Together, these preclinical data strongly support the translation of this combination therapy into clinical trials for CRC patients.

Coinhibition of topoisomerase 1 and BRD4-mediated pause release selectively kills pancreatic cancer via readthrough transcription.

Pancreatic carcinoma lacks effective therapeutic strategies resulting in poor prognosis. Transcriptional dysregulation due to alterations in KRAS and MYC affects initiation, development, and survival of this tumor type. Using patient-derived xenografts of KRAS- and MYC-driven pancreatic carcinoma, we show that coinhibition of topoisomerase 1 (TOP1) and bromodomain-containing protein 4 (BRD4) synergistically induces tumor regression by targeting promoter pause release. Comparing the nascent transcriptome with the recruitment of elongation and termination factors, we found that coinhibition of TOP1 and BRD4 disrupts recruitment of transcription termination factors. Thus, RNA polymerases transcribe downstream of genes for hundreds of kilobases leading to readthrough transcription. This occurs during replication, perturbing replisome progression and inducing DNA damage. The synergistic effect of TOP1 + BRD4 inhibition is specific to cancer cells leaving normal cells unaffected, highlighting the tumor's vulnerability to transcriptional defects. This preclinical study provides a mechanistic understanding of the benefit of combining TOP1 and BRD4 inhibitors to treat pancreatic carcinomas addicted to oncogenic drivers of transcription and replication.

Rescue Allocation Modes in Eurotransplant Kidney Transplantation: Recipient Oriented Extended Allocation Versus Competitive Rescue Allocation-A Retrospective Multicenter Outcome Analysis.

BACKGROUND: Whenever the kidney standard allocation (SA) algorithms according to the Eurotransplant (ET) Kidney Allocation System or the Eurotransplant Senior Program fail, rescue allocation (RA) is initiated. There are 2 procedurally different modes of RA: recipient oriented extended allocation (REAL) and competitive rescue allocation (CRA). The objective of this study was to evaluate the association of patient survival and graft failure with RA mode and whether or not it varied across the different ET countries. METHODS: The ET database was retrospectively analyzed for donor and recipient clinical and demographic characteristics in association with graft outcomes of deceased donor renal transplantation (DDRT) across all ET countries and centers from 2014 to 2021 using Cox proportional hazards methods. RESULTS: Seventeen thousand six hundred seventy-nine renal transplantations were included (SA 15 658 [89%], REAL 860 [4.9%], and CRA 1161 [6.6%]). In CRA, donors were older, cold ischemia times were longer, and HLA matches were worse in comparison with REAL and especially SA. Multivariable analyses showed comparable graft and recipient survival between SA and REAL; however, CRA was associated with shorter graft survival. Germany performed 76% of all DDRTs after REAL and CRA and the latter mode reduced waiting times by up to 2.9 y. CONCLUSIONS: REAL and CRA are used differently in the ET countries according to national donor rates. Both RA schemes optimize graft utilization, lead to acceptable outcomes, and help to stabilize national DDRT programs, especially in Germany.

Autotransplantation for the treatment of severe renal artery stenosis in a solitary kidney after repeated percutaneous transluminal angioplasty: a case report.

A 66-year-old female suffering from massive atherosclerosis with a long history of renal artery stenosis in the left solitary kidney was admitted to reevaluate an in-stent restenosis. Advanced peripheral arterial disease had formerly been treated by aortobifemoral bypass surgery and a highly eccentric infrarenal abdominal aortic stenosis of 70 - 80% had been treated by patch angioplasty. In this patient several percutaneous transluminal renal angioplasties after a former stent deployment had resulted in recurrent in-stent restenoses. The renal artery stenosis was reevaluated and a re-angioplasty attempt was unsuccessful due to technical failure. Blood pressure remained difficult to manage. Renal function decreased as a result of presumed acute renal failure. A further progression of the renal artery stenosis was found. Autotransplantation to the left iliac fossa was done, because aortorenal bypass was considered impossible. Renal function normalized and follow-up Doppler ultrasonography examinations revealed a newly developed ostial anastomotic stenosis of 60 - 70%. While medical therapy and percutaneous transluminal angioplasty with stent deployment are common treatment options, surgical interventions are reserved for cases of complex stenoses. Autotransplantation as a complex option in the treatment of renal artery stenosis seems to be an adequate alternative in patients with severe, generalized atherosclerosis after failure of interventional procedures and the impossibility of standard surgical techniques.

Minimally invasive video-assisted parathyroidectomy (MIVAP) versus conventional parathyroidectomy for renal hyperparathyroidism: a retrospective multicenter study.

To compare minimally invasive video-assisted parathyroidectomy (MIVAP) versus conventional surgery for renal hyperparathyroidism (rHPT). Between 2006 and 2020, 53 patients underwent MIVAP and 182 underwent conventional parathyroidectomy for rHPT at the Kliniken Essen-Mitte and Knappschaftskrankenhaus Bochum, respectively. Two propensity score-matched groups were retrospectively analyzed: the MIVAP group (VG; n = 53) and the conventional group (CG; n = 53). To assess long-term results, the patients were questioned prospectively (VG; n = 17, and CG; n = 26). The VG had a smaller incision (2.8 vs. 4.8 cm), shorter operation duration (81.0 vs. 13.9 min), and shorter duration of stay (2.4 vs. 5.7 days) (p < 0.0001) but a smaller drop in parathyroid hormone (PTH) postoperatively (81.3 vs. 85.5%. p = 0.022) than the CG. The conversion rate was 9.4% (n = 5). The VG had better Patient Scar Assessment Scale (PSAS) scores (10.8 vs. 11.7 p = 0.001) but worse SF-12 health survey scores (38.7 vs. 45.8 for physical health and 46.7 vs. 53.4 for mental health) (p < 0.0001). The PTH level at follow-up was higher in the VG (162.7 vs. 59.1 ng/l, p < 0.0001). There were no differences in morbidity, number of removed parathyroid glands, disease persistence, late rHPT relapse and need for repeat surgery between groups. MIVAP was superior to conventional parathyroidectomy regarding aesthetic outcomes and cost effectiveness. Conventional surgery showed better control of PTH levels and health scores on follow-up than MIVAP, without any impact on rHPT relapse and need for repeat surgery.Trail registration number and date of registration: DRKS00022545 on 14.12.2020.