Long-term patency of arteriovenous fistulas for hemodialysis: A decade's experience in a transplant unit.

BACKGROUND: The heterogeneous quality of studies on arteriovenous fistulas outcome, with variable clinical settings and large variations in definitions of patency and failure rates, leads to frequent misinterpretations and overestimation of arteriovenous fistula patency. Hence, this study aimed to provide realistic and clinically relevant long-term arteriovenous fistula outcomes. METHODS: We retrospectively analyzed all autologous arteriovenous fistulas at our center over a 10-year period (2012-2022). Primary and secondary patency analysis was conducted using the Kaplan-Meier method; multivariate analysis of variance was used to detect outcome predictors. Vascular access-specific endpoints were defined according to the European guidelines on vascular access formation. FINDINGS: Of 312 arteriovenous fistulas, 57.5% (n = 181) were radio-cephalic (RC_AVF), 35.2% (n = 111) brachio-cephalic (BC_AVF), and 6.3% (n = 20) brachio-basilic (BB_AVF). 6, 12, and 24 months follow-up was available in 290 (92.1%), 282 (89.5%), and 259 (82.2%) patients, respectively. Primary patency rates at 6, 12, and 24 months were 39.5%, 34.8%, and 27.2% for RC_AVF, 58.3%, 44.4%, and 27.8% for BC_AVF, and 40.0%, 42.1%, and 22.2% for BB_AVF (p = 0.15). Secondary patency rates at 6, 12, and 24 months were 65.7%, 63.8%, and 59.0% for RC_AVF, 77.7%, 72.0%, and 59.6% for BC_AVF, and 65.0%, 68.4%, and 61.1% for BB_AVF (p = 0.29). Factors associated with lower primary and secondary patency were hemodialysis at time of arteriovenous fistula formation (p = 0.037 and p = 0.024, respectively) and higher Charlson Comorbidity Index (p = 0.036 and p < 0.001, respectively). Previous kidney transplant showed inferior primary patency (p = 0.005); higher age inferior secondary patency (p < 0.001). DISCUSSION: Vascular access care remains challenging and salvage interventions are often needed to achieve maturation or maintain patency. Strict adherence to standardized outcome reporting in vascular access surgery paints a more realistic picture of arteriovenous fistula patency and enables reliable intercenter comparison.

Peritransplant Varicosis After Simultaneous Pancreas and Kidney Transplantation Is an Uncommon Cause of Late-Onset and Recurrent Gastrointestinal Bleeding.

Ectopic peritransplant varicosis represents an uncommon cause of late-onset gastrointestinal (GI) bleeding after simultaneous pancreas and kidney transplantation (SPK). We report on a 53-year-old female patient who suffered from recurrent upper GI bleeding seven years after SPK with persistent graft function. Upper endoscopy revealed perianastomotic angiodysplasias, treated by clipping and Argon-Plasma-Coagulation. Repeated endoscopy showed no signs of anastomotic ulcer. With persistent symptoms, computed tomography and angiography revealed extensive ectopic varicosis around the pancreas and duodenal graft. With no signs of portal hypertension, pancreas graft venous outflow impairment or arterio-venous fistula, the origin of variceal formation remained unknown. The extended finding did not allow for endovascular treatment by embolization. Surgery with extensive variceal ligation led to persistent cessation of hemorrhage and maintained stable graft function. In patients with unclear recurrent upper GI bleeding after SPK, one should consider ectopic peritransplant varicosis as an exceptional bleeding cause. If endoscopic treatments fail, angiography should be performed to rule out unusual causes of vascular complications. In case of extensive peritransplant varicosis, surgery may remain the only successful therapy, whenever possible including graft preservation in well-functioning grafts.

Safety of Kidney Biopsy when Performed as an Outpatient Procedure.

INTRODUCTION: Kidney biopsy remains the gold standard for the diagnosis of most renal diseases. A major obstacle to performing a biopsy is safety concerns. However, many safety measures are not evidence based and therefore vary widely between centers. We sought to determine the rate and timing of kidney biopsy complications in our center, to compare the complication rate between native and transplant kidney biopsies, to evaluate the feasibility of performing kidney biopsies as an outpatient procedure and the value of a postbiopsy ultrasound before discharge, and to identify risk factors for complications. METHODS: We performed a single-center, retrospective, observational study at the Division of Nephrology of the University Hospital Zurich including all patients who underwent renal biopsy between January 2005 and December 2017. Major bleeding (primary outcome) and any other bleeding or nonbleeding complications (secondary outcomes) were compared between native and transplant kidney biopsies and between inpatient and outpatient procedures and correlated with clinical factors possibly affecting bleeding risk. RESULTS: Overall, 2,239 biopsies were performed in 1,468 patients, 732 as inpatient and 1,507 as outpatient procedures. Major bleeding was observed in 28 (3.8%) inpatient and in 15 (1.0%) outpatient procedures, totaling to 43 (1.9%) of all biopsies. Major bleeding requiring intervention amounted to 1.0% (0.5% of outpatient procedures). Rate of major bleeding was similar between native and transplant kidneys. 13/15 (87%) bleeding episodes in planned outpatient procedures were detected during the 4-h surveillance period. Risk factors for bleeding were aspirin use, low eGFR, anemia, cirrhosis, and amyloidosis. Routine postbiopsy ultrasound did not change management. CONCLUSIONS: Kidney biopsy is an overall safe procedure and can be performed as an outpatient procedure in most patients with an observation period as short as 4 h. The value of routine postbiopsy ultrasound is questionable.

Dialysis after graft loss: a Swiss experience.

BACKGROUND: Patients returning to dialysis after graft loss have high early morbidity and mortality. METHODS: We used data from the Swiss Transplant Cohort Study to describe the current practice and outcomes in Switzerland. All patients who received a renal allograft between May 2008 and December 2014 were included. The patients with graft loss were divided into two groups depending on whether the graft loss occurred within 1 year after transplantation (early graft loss group) or later (late graft loss group). Patients with primary non-function who never gained graft function were excluded. RESULTS: Seventy-seven out of 1502 patients lost their graft during follow-up, 40 within 1 year after transplantation. Eleven patients died within 30 days after allograft loss. Patient survival was 86, 81 and 74% at 30, 90 and 365 days after graft loss, respectively. About 92% started haemodialysis, 62% with definitive vascular access, which was associated with decreased mortality (hazard ratio = 0.28). At the time of graft loss, most patients were on triple immunosuppressive therapy with significant reduction after nephrectomy. One year after graft loss, 77.5% (31 of 40) of patients in the early and 43.2% (16 out of 37) in the late-loss group had undergone nephrectomy. Three years after graft loss, 36% of the patients with early and 12% with late graft loss received another allograft. CONCLUSION: In summary, our data illustrate high mortality, and a high number of allograft nephrectomies and re-transplantations. Patients commencing haemodialysis with a catheter had significantly higher mortality than patients with definitive access. The role of immunosuppression reduction and allograft nephrectomy as interdependent factors for mortality and re-transplantation needs further evaluation.

Bone metabolism dynamics in the early post-transplant period following kidney and liver transplantation.

Bone disease contributes to relevant morbidity after solid organ transplantation. Vitamin D has a crucial role for bone metabolism. Activation of vitamin D depends on the endocrine function of both, liver and kidney. Our study assessed key markers of bone metabolism at time of transplantation and 6 months after transplantation among 70 kidney and 70 liver recipients. In 70 kidney recipients 25-OH vitamin D levels did not differ significantly between peri-transplant (median 32.5nmol/l) and 6 months post-transplant (median 41.9nmol/l; P = 0.272). Six months post-transplant median 1, 25-(OH)2 vitamin D levels increased by >300% (from 9.1 to 36.5ng/l; P<0.001) and median intact parathyroid hormone levels decreased by 68.4% (from 208.7 to 66.0 ng/l; P<0.001). Median ß-Crosslaps (CTx) and total procollagen type 1 amino-terminal propeptide (P1NP) decreased by 65.1% (from 1.32 to 0.46ng/ml; P<0.001) and 60.6% (from 158.2 to 62.3ng/ml; P<0.001), respectively. Kidney recipients with incident fractures had significantly lower levels of 1, 25-(OH)2 vitamin D at time of transplantation and of intact parathyroid hormone 6 months post-transplant. Among 70 liver recipients, 25-OH vitamin D, 1, 25-(OH)2 vitamin D and intact parathyroid hormone levels were not significantly altered between peri-transplant and 6 months post-transplant. Contrary to kidney recipients, median CTx increased by 60.0% (from 0.45 to 0.72 ng/ml; P = 0.002) and P1NP by 49.3% (from 84.0 to 125.4ng/ml; P = 0.001) in the longitudinal course. Assessed biomarkers didn't differ between liver recipients with and without fractures. To conclude, the assessed panel of biomarkers proved highly dynamic after liver as well as kidney transplantation in the early post-transplant period. After kidney transplantation a significant gain in 1, 25-(OH)2 vitamin D combined with a decline in iPTH, CTx and P1NP, whereas after liver transplantation an increase in CTx and P1NP were characteristic.

Evolution of lung and kidney allograft function in patients receiving kidney after lung transplantation.

Calcineurin inhibitor (CNI) toxicity leads to end-stage renal disease in almost half of long-term survivors after lung transplantation, some of them receiving kidney transplants. Little is known about the outcomes of kidney and lung allograft function following kidney after lung transplantation (KALTPL) in the modern era. We retrospectively analyzed a group of 13 consecutive patients who received a KALTPL with respect to their renal and pulmonary function and immunological evolution over 2 years. We documented a stable evolution of forced expiratory volume in 1 second (FEV1) after KALTPL in most patients as well as an excellent kidney graft during the 2-year follow-up period. In our small cohort, living donations showed a significantly higher estimated glomerular filtration rate compared to deceased donation (75.7 compared to 41.6 mL/min). Patients who received a preemptive KALTPL were more likely to improve their lung function after KALTPL. Four patients developed de novo donor-specific antibodies (DSA) against the kidney graft. There were no DSA against shared antigens from the lung allograft. De novo DSA did not lead to graft loss in any patient. All 13 patients survived the first 24 months after KALTPL.

Long-term follow-up of pulmonary function in Fabry disease: A bi-center observational study.

INTRODUCTION: Fabry disease (FD) is a lysosomal storage disorder leading to decreased α-galactosidase A enzyme activity and subsequent abnormal accumulation of glycosphingolipids in various organs. Although histological evidence of lung involvement has been demonstrated, the functional impact of these changes is less clear. MATERIALS AND METHODS: Adult patients with FD who had yearly pulmonary function tests (PFT) at two centers from 1999 thru 2015 were eligible for this observational study. Primary outcome measures were the change in forced expiratory volume in the first second (FEV1) and FEV1/FVC over time. As secondary outcome we investigated sex, smoking, enzyme replacement therapy (ERT), residual enzyme activity, and Mainz Severity Score Index as possible predictors. RESULTS: 95 patients (41% male, 38.2 ± 14.5 years) were included. The overall prevalence of bronchial obstruction (BO, (FEV1/FVC < 70%)) was 46%, with male sex, age and smoking as significant predictors. FEV1 decreased 29 ml per year (95% CI -36, -22 ml, p<0.0001). FEV1 decline was significantly higher in males (p = 0.009) and in patients on ERT (p = 0.004). Conclusion: Pulmonary involvement seems to be a relevant manifestation of Fabry disease, and routine PFTs should therefore be included in the multidisciplinary follow-up of these patients.

Infections in De Novo Kidney Transplant Recipients Treated With the RANKL Inhibitor Denosumab.

BACKGROUND: Infections are a major cause of morbidity and mortality in kidney allograft recipients. In this post hoc analysis of a randomized clinical trial which tested the effect of denosumab on bone mineral density, we assessed the impact of this drug on the incidence and severity of infections in the first year after kidney transplantation. METHODS: In this clinical trial, we randomized 90 de novo kidney transplant recipients shortly after transplantation to either denosumab on top of standard treatment (calcium and vitamin D) (n = 46), or to standard treatment alone (n = 44). Among all adverse events, we analyzed all infections that occurred within the first year after transplantation, and compared their incidence and severity in both groups. RESULTS: Overall, we identified more infections (n = 146) in the denosumab group than in the control group (n = 99). The most common infections were urinary tract infection (cystitis) (34.9% vs 25.2%), cytomegalovirus viremia (17.8% vs 24.2%), flu-like syndrome (11.6% vs 14.1%), polyoma (BK) viremia (8.2% vs 11.1%), and herpes simplex infections (5.5% vs 4.0%). Episodes of urinary tract infection (cystitis) occurred more often in the denosumab than in the control group (51 vs 25 episodes in 24 vs 11 patients, P = 0.008), whereas episodes of transplant pyelonephritis or urosepsis were not more frequent (3 vs 5 episodes). CONCLUSIONS: This post hoc analysis reveals that treatment with denosumab to prevent bone loss in first-year kidney transplant recipients was associated with more frequent episodes of urinary tract infections, whereas other infections occurred with similar frequency in both treatment groups.

Visualization of Parathyroid Hyperplasia Using 18F-Fluorocholine PET/MR in a Patient With Secondary Hyperparathyroidism.

Several imaging modalities exist for the detection of parathyroid adenomas in patients with primary hyperparathyroidism. Unlike solitary parathyroid adenoma, parathyroid hyperplasia in patients with secondary hyperparathyroidism hitherto is difficult to assess with any imaging modality. Our case of a young patient with chronic kidney failure illustrates that F-fluorocholine PET/MR might be an imaging tool suitable for the diagnosis and presurgical assessment of parathyroid hyperplasia.

Insufficient medication documentation at hospital admission of cardiac patients: a challenge for medication reconciliation.

BACKGROUND: Medication errors may occur when hospital doctors are not adequately informed about a patient's prescribed drugs. METHODS: The drug lists of 103 patients who were electively admitted for coronary angiography were assessed. Discrepancies between lists noted in admission letters, patient's personal medication lists, and medication histories were analyzed. RESULTS: Patients took a mean of 5 +/- 3 drugs. Nine percent of all drugs taken were only mentioned when a systematic medication history was obtained but were not stated in admission letters or on medication lists. Only 88% of admission letters reported the patient's medication. Twenty-one percent of generics were incorrectly documented as originals in the admission letter. Less than 50% of patients taking >or= 4 drugs had a written instruction on how to take their medication. A total of 86 drugs actually taken by the patients were not identical to those listed in the referral letter or the medication list, leaving uncertainties as to how outpatient medication should be continued. Medication was modified in 25% of all patients at hospital discharge. CONCLUSIONS: Instructions for patients taking multiple drugs and information in admission letters need to be improved. These results underline the importance of medication reconciliation at hospital admission.

Systematic quantitative overviews of the literature to determine the value of diagnostic tests for predicting acute appendicitis: study protocol.

BACKGROUND: Suspected acute appendicitis is the most frequent cause for emergency operations in visceral surgery worldwide. In approximately twenty percent of all cases however, the diagnosis is incorrect and patients undergo surgery without having acute appendicitis. Operations of bland appendices put patients at risk and entail a serious waste of resources. Several highly accurate tests have been introduced to diagnose acute appendicitis. The false positive rate however, has not changed over the last twenty years. Given the variation that exists in both practice and research, the uncertainty regarding the quality of the underlying evidence, there is a clear need for comprehensive, systematic and quantitative overviews of the diagnostic value of the various tests purported to be predictive of acute appendicitis. METHODS: Literature will be identified searching general bibliographic databases (MEDLINE and EMBASE), specialist computer databases (DARE, Cochrane Database of Systematic Reviews, conference proceedings, MEDION, SCISEARCH, BIOSIS) without language restrictions. We will contact experts and the manufacturers of tests. Hand-searching will complete our searches. Identified articles will be selected according to populations, tests, outcomes and study design. Papers meeting the selection criteria will be appraised to rate their methodological quality. Analysis will include exploration of heterogeneity in results. We will conduct meta-analyses to generate summary estimates of test accuracy measures and summary ROC curves where appropriate. If meta-analysis is considered to be inappropriate, we will describe the identified evidence in the context of appraised quality. DISCUSSION: These reviews should lead to formulation of recommendations for current practice and future research.