Outcomes of upper arm axillary artery and brachial artery arteriovenous grafts.

BACKGROUND: We compared the outcomes of upper arm arteriovenous grafts (AVGs) in a large, prospectively collected data set to determine if there are clinically significant differences in axillary artery-based and brachial artery-based AVGs. METHODS: Patients who received upper arm AVGs within the Society of Vascular Surgery Vascular Quality Initiative (VQI) dataset were identified. The primary outcome measures were primary and secondary patency loss at 12-month follow-up. Other outcomes included were wound infection, steal syndrome, and arm swelling at 6-month follow-up. The log-rank test was used to evaluate patency loss using Kaplan-Meier analysis, and Cox proportional hazards models were used to examine adjusted association between inflow artery (brachial artery vs axillary artery) and outcomes, adjusting for configuration (straight vs looped). RESULTS: Among 3637 upper extremity AVGs in the VQI (2010-2017), there were 510 upper arm brachial artery AVGs and 394 upper arm axillary artery AVGs. Patients with axillary artery AVGs were more likely to be female (72% vs 56%, p < 0.001) and underwent general anesthesia (61% vs 57%, p < 0.05). In univariable analysis, the 12-month primary patency (54% vs 63%, p = 0.03) and secondary patency (81% vs 89%, p = 0.007) were lower for axillary artery AVGs than upper arm brachial artery AVGs. In multivariable analysis, although wound infection and arm swelling were similar at 6-month follow up, axillary artery AVGs were more likely to have steal syndrome (adjusted Hazard Ratio (aHR) = 2.6, 95% Confidence Interval (CI) 1.2,5.6, p = 0.017). In addition, axillary artery AVGs were associated with higher rates of 12-month primary patency loss (aHR = 1.6, 95% CI 1.2-2.2, p = 0.002) and 12-month secondary patency loss (aHR = 2.0, 95% CI 1.3-3.3, p = 0.005). CONCLUSIONS: From this observational study analyzing the outcomes of upper extremity hemodialysis access, axillary artery AVGs were associated with significantly lower patency rates and higher risk of steal syndrome than brachial artery AVGs.

Comparing Outcomes of Upper Extremity Brachiobasilic Arteriovenous Fistulas and Arteriovenous Grafts: A Systematic Review and Meta-Analysis.

OBJECTIVE: It is unclear what the optimal upper extremity hemodialysis access is for patients without a suitable cephalic vein for arteriovenous fistulas (AVFs). The objective of this systematic review and meta-analysis was to compare the outcomes for upper extremity transposed brachiobasilic AVFs (BBAVFs) and prosthetic arteriovenous grafts (AVGs). METHODS: A systematic review was performed to identify all English publications and abstracts comparing the patency outcomes of upper extremity BBAVFs and AVGs (January 1st, 1994 to April 1st, 2020). The outcomes assessed were 1-year and 2-year primary and secondary patency rates. Pooled odds ratios (OR) were calculated using the random-effects model, and I2 statistic was used to assess between-study variability. RESULTS: Twenty-three studies examining 2799 patients were identified and included in the study. The 1-year primary patency rates (OR = 1.68, 95% CI 1.24-2.28, p = 0.001, I2 = 69.40%) and 2-year primary patency rates (OR = 2.33, 95% CI 1.59-3.43, p < 0.001, I2 = 68.26%) were significantly better for BBAVFs than AVGs. Compared to AVGs, the 1-year secondary patency rates (OR = 1.45, 95% CI 1.05-1.98, p = 0.022, I2 = 56.64%) and 2-year secondary patency rates (OR = 1.93, 95% CI 1.39-2.68, p < 0.001, I2 = 57.61%) were also significantly higher for BBAVFs. CONCLUSION: The outcomes for upper extremity BBAVFs appear to be consistently superior to prosthetic hemodialysis access. This analysis supports the preferential placement of BBAVFs over AVGs in patients with a suitable upper extremity basilic vein.

The role of novel COQ8B mutations in glomerulopathy and related kidney defects.

BACKGROUND AND OBJECTIVES: Glomerulopathies affect kidney glomeruli and can lead to end-stage renal disease if untreated. Clinical and experimental evidence have identified numerous (>20) genetic mutations in the mitochondrial coenzyme Q8B protein (COQ8B) primarily associated with nephrotic syndrome. Yet, little else is understood about COQ8B activity in renal pathogenesis and its role in mitochondrial dysfunction. We identified additional novel COQ8B mutations in a glomerulopathy patient and aimed to define the potential structural and functional defects of COQ8B mutations. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: Whole exome sequencing was performed on a Hispanic female presenting with proteinuria. Novel mutations in the COQ8B gene were identified. The effects of mutation on protein function, mitochondrial morphology, and disease progression were investigated by histopathology, transmission electron microscopy, homology modeling, and in silico structural analysis. RESULTS: We have characterized the pathophysiology of novel COQ8B mutations, compound heterozygous for two alterations c.1037T>G (p.I346S), and c.1560G>A (p.W520X), in the progression of proteinuria in a Hispanic female. Histopathology revealed defects in podocyte structure and mitochondrial morphology. In silico and computation analyses highlight possible structural origins of COQ8B dysfunction in the presence of mutations. CONCLUSIONS: Novel mutations in COQ8B present promising biomarkers for the early detection and therapeutic targeting of mitochondrial glomerulopathy. Insights from structural modeling suggest roles of mutation-dependent alterations in COQ8B allosteric regulation, protein folding, or stability in renal pathogenesis.

Multicenter Clinicopathologic Correlation of Kidney Biopsies Performed in COVID-19 Patients Presenting With Acute Kidney Injury or Proteinuria.

RATIONALE & OBJECTIVE: Kidney biopsy data inform us about pathologic processes associated with infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We conducted a multicenter evaluation of kidney biopsy findings in living patients to identify various kidney disease pathology findings in patients with coronavirus disease 2019 (COVID-19) and their association with SARS-CoV-2 infection. STUDY DESIGN: Case series. SETTING & PARTICIPANTS: We identified 14 native and 3 transplant kidney biopsies performed for cause in patients with documented recent or concurrent SARS-CoV-2 infection treated at 7 large hospital systems in the United States. OBSERVATIONS: Men and women were equally represented in this case series, with a higher proportion of Black (n=8) and Hispanic (n=5) patients. All 17 patients had SARS-CoV-2 infection confirmed by reverse transcriptase-polymerase chain reaction, but only 3 presented with severe COVID-19 symptoms. Acute kidney injury (n=15) and proteinuria (n=11) were the most common indications for biopsy and these symptoms developed concurrently or within 1 week of COVID-19 symptoms in all patients. Acute tubular injury (n=14), collapsing glomerulopathy (n=7), and endothelial injury/thrombotic microangiopathy (n=6) were the most common histologic findings. 2 of the 3 transplant recipients developed active antibody-mediated rejection weeks after COVID-19. 8 patients required dialysis, but others improved with conservative management. LIMITATIONS: Small study size and short clinical follow-up. CONCLUSIONS: Cases of even symptomatically mild COVID-19 were accompanied by acute kidney injury and/or heavy proteinuria that prompted a diagnostic kidney biopsy. Although acute tubular injury was seen among most of them, uncommon pathology such as collapsing glomerulopathy and acute endothelial injury were detected, and most of these patients progressed to irreversible kidney injury and dialysis.

Upper Arm Arteriovenous Grafts are Superior over Forearm Arteriovenous Grafts in Upper Extremity Dialysis Access.

BACKGROUND: In this study, we compared the outcomes of forearm arteriovenous grafts (AVGs) and upper arm AVGs in a large, prospectively collected data set, which represents real-world experience with upper extremity prosthetic dialysis access, to determine if there are clinically significant differences in the upper arm and forearm positions. METHODS: We identified 2,063 patients who received upper extremity AVGs within the Vascular Quality Initiative data set (2010-2018). Axillary to axillary upper arm AVGs were excluded (n = 394) from the analysis. The main outcome measures were primary and secondary patency rates at 12 months. Other outcomes were 6-month wound infection, steal syndrome, and arm swelling. The log-rank test was used to evaluate patency loss using a Kaplan-Meier analysis. Cox proportional hazards models were used to examine adjusted association between locations (forearm and upper arm) and outcomes. RESULTS: There were 1,160 forearm AVGs and 509 upper arm brachial artery AVGs in the study cohort. Patients with forearm AVGs were more likely to have a body mass index > 30 (45% vs. 38%, P = 0.013), no history of previous access (73% vs. 63%, P < 0.001), and underwent local-regional anesthesia (56% vs. 43%, P < 0.001). The 12-month primary patency (51.5% vs. 62.9%, P < 0.001) and secondary patency (76.4% vs. 89.1%, P < 0.001) were significantly lower for forearm AVGs. Wound infection, steal syndrome, and arm swelling were similar between forearm AVGs and upper arm AVGs at the 6-month follow-up. In multivariable analysis, the primary patency loss (adjusted hazard ratio (aHR) 1.66, 95% confidence interval (CI) 1.33-2.01, P < 0.001) and 12-month secondary patency loss (aHR 2.71, 95% CI 1.84-3.98, P < 0.001) were significantly higher for forearm AVGs at 12 months. CONCLUSIONS: From this observational study of the Vascular Quality Initiative data set, the primary and secondary patency rates were superior for upper arm brachial artery AVGs compared with forearm AVGs.

Laparoscopic peritoneal dialysis catheter placement is associated with decreased deep organ infection and reoperation.

INTRODUCTION: The optimal method for placement of peritoneal dialysis catheters (PDC) is unclear. The objective of this study was to compare the outcomes of laparoscopic and open surgical placement of PDC. MATERIALS AND METHODS: Patients who underwent laparoscopic (LPD) and open (OPD) surgical placement of PDC between 2007 and 2011 were identified from the American College of Surgeons National Surgical Quality Initiative Project (NSQIP) dataset using current procedural terminology (CPT) and international classification of diseases 9th revision (ICD-9) codes. Perioperative outcomes were compared using Fisher's exact test for categorical variables, Student's t-test and Gamma regression were used for continuous variables. Catheter function was not reported in the dataset. RESULTS: There were 1,560 PDC procedures in our study and most were performed laparoscopically (89%). 83% of these procedures were performed by general surgeons, mostly, with the patients under general anesthesia (95%). OPD was associated with a higher rate of perioperative deep organ infection (3.5% vs. 1.1%, p = 0.02) and need for reoperation (10.4% vs. 5.0%, p = 0.007). Operative time was, however, significantly longer with LPD (53.3 vs. 45.5 minutes, p < 0.001). In multivariate analysis, OPD was independently associated with increased risk of perioperative deep organ infection (odds ratio (OR) 3.7,95%, Confidence Interval (CI) 1.3 - 10.2, p = 0.01) and reoperation (OR 2.3, 95% CI 1.3 - 4.1, p = 0.005). CONCLUSIONS: Laparoscopic PDC placement is more commonly performed and is associated with a lower risk of perioperative deep organ infection and reoperation than the open surgical approach. When possible, laparoscopic PDC placement might be preferable over open surgical placement.