Ji Yoon Choi

Comparison of surgical and endovascular salvage procedures for juxta-anastomotic stenosis in autogenous wrist radiocephalic arteriovenous fistula.

BACKGROUND Although dysfunctional radiocephalic arteriovenous fistulas (RCAVFs) are typically treated surgically, the endovascular approach is also considered suitable. The aim of this retrospective study was to compare the cumulative patency rates following surgical and endovascular salvaging of dysfunctional RCAVFs, and to evaluate whether the maturity of vascular access sites at the time of treatment influenced the outcomes. METHODS A total of 60 patients underwent surgical or endovascular salvage treatment for juxta-anastomotic stenosis of autogenous wrist RCAVFs: 35 patients underwent proximal neo-anastomosis and 25 underwent percutaneous transluminal angioplasty (PTA). RESULTS Clinical and anatomical success rates were, respectively, 100% and 97.1% in the surgery group, and 100% and 96.0% in the angioplasty group (P = 0.81). The post-treatment restenosis rate was higher in the angioplasty group (n = 11, 46.0%) than in the surgery group (n = 8, 22.8%), without reaching statistical significance (P = 0.15). In a Kaplan-Meier analysis, the primary and assisted primary patency rates were significantly higher in the surgery group (P = 0.036 and P = 0.026, respectively), but there was no significant difference in secondary patency rates between the groups (P = 0.52). When stratified by RCAVF maturity at the time of treatment, no significant difference was noted in primary patency rates between the treatment groups. After adjusting for other variables, the relative risk of restenosis was significantly higher in the angioplasty group (hazard ratio 2.56; 95% confidence interval 1.02-6.46; P = 0.046). CONCLUSIONS Post-treatment primary and assisted primary patency rates after proximal neo-anastomosis were significantly higher than after PTA, and RCAVF maturity did not influence the outcomes.

Pancreas Transplantation From Living Donors: A Single Center Experience of 20 Cases.

Living donor pancreas transplantation (LDPT) has several advantages over deceased donor pancreas transplantation (DDPT), including better HLA matching, shorter ischemic time, and shorter waiting time. It remains an attractive option for diabetes mellitus (DM) patients with end stage renal disease. We reviewed 20 cases of LDPT performed in Asan Medical Center between October 1992 and March 2015. Six cases (30%) were pancreas transplantation alone (PTA), and the rest (70%) were simultaneous pancreas and kidney transplantation (SPK). Relations of donor and recipient were parents in 7 (35%), siblings in 6 (30%), spouse in 6 (30%), and cousin in 1 (5%). Graft survival in SPK at 1, 3, 5, and 10 years was 91.7%, 83.3%, 83.3%, and 83.3%, respectively, and that in PTA recipients was 50%, 33.3%, 16.7%, and 16.7%, respectively (p = 0.005). Causes of graft failure in SPK were thrombosis (one case), and rejection (one case), whereas those in PTA were noncompliance (two cases), thrombosis (one case), reflux pancreatitis (one case), and chronic rejection (one case). In terms of pancreas exocrine drainage, two grafts (25%) maintained their function in bladder drainage, while all grafts maintained in enteric drainage p < 0.05). Seven (35%) donors experienced minor pancreatic juice leakage and one underwent reoperation due to postoperative hematoma. Most donors maintained normoglycemia and normal renal function. However, two donors developed DM (at 1 and 90 months postdonation), and were treated with oral hypoglycemic agents. Graft survival in PTA recipients was poorer than in SPK due to poor compliance and bladder drainage–related problems. The surgical and metabolic complication rates of donors can be minimized by applying strict donor criteria. Therefore, LDPT with enteric drainage is an acceptable treatment for SPK.

Analysis of 4000 kidney transplantations in a single center: Across immunological barriers.

AbstractKidney transplant (KT) is the optimal renal replacement therapy for patients with end-stage renal disease (ESRD). The demand for kidneys, however, continues to exceed the supply. To overcome this problem, efforts to extend the donor pool by including human leukocyte antigen (HLA)- and ABO-incompatible (ABOi) KTs are increasing. The aim of this article was to retrospectively review data on recipients, donor profiles, and clinical outcomes in 4000 cases of KT. In addition, we analyzed clinical outcomes in ABOi and flow-cytometric crossmatch (FCXM) positive KT in a subgroup analysis.This was a retrospective, observational study using data extracted from medical records. A total of 4000 consecutive patients who underwent KT at our institution from January 1990 to February 2015 were included in this study. KTs across immunological barriers such as ABO incompatible (276 cases, 6.9%), FCXM positive (97 cases, 2.4%), and positive complement-dependent cytotoxicity (CDC) XM KT (16 cases, 0.4%) were included.From a Kaplan–Meier analysis, overall patient survival (PS) rates after KT at 1, 5, 10, and 20 years were 96.9%, 95.1%, 92.0%, and 88.9%, respectively. The overall graft survival (GS) rates after KT at 1, 5, 10, and 20 years were 96.3%, 88.9%, 81.2%, and 67.4%, respectively. Our subgroup analysis suggested that overall PS, GS, death-censored GS, and rejection-free GS in ABOi KT showed no significant differences in comparison with ABO-compatible KT if adequate immunosuppressive treatment was performed. The overall PS rate in patients who underwent FCXM positive KT did not differ significantly from that of the control group during the 3-year follow-up (P = 0.34). The overall GS, death-censored GS, and rejection-free GS also did not differ significantly between the FCXM KT and control groups (P = 0.99, 0.42, and 88).The outcomes of KTs continually improved during the study period, while the annual number of KTs increased. ABO or FCXM positive KTs can be performed safely with successful graft outcomes.

Renal autotransplantation in open surgical repair of suprarenal abdominal aortic aneurysm

Although the standard treatment of abdominal aortic aneurysm has shifted from open surgery to endovascular repair, open surgery has remained the standard of care for complex aneurysms involving the visceral arteries and in patients unsuitable for endovascular aneurysm repair. Postoperative renal insufficiency may occur after open surgical repair of suprarenal abdominal aortic aneurysm. Methods of minimizing renal ischemic injury include aortic cross-clamping and renal reconstruction techniques. This report describes the use of renal autotransplantation for renal reconstruction during open surgical repair of a suprarenal abdominal aortic aneurysm. This technique was successful, suggesting its feasibility for open suprarenal abdominal aortic aneurysm repair, minimizing renal ischemic injury and optimizing postoperative renal function.

Surgical Treatment of Central Venous Catheter Related Septic Deep Venous Thrombosis

OBJECTIVE/BACKGROUND The aim of this study was to evaluate the clinical features and outcomes of catheter related central venous thrombosis and whether a surgical approach can be an effective treatment modality in selected cases that are refractory to conservative management. METHODS This was a retrospective review of the 46 consecutive patients who were suspected of having central venous catheter related infected deep venous thrombosis and who met the eligibility criteria. RESULTS Conservative management achieved clinical improvement in 26 (56.5%) patients and failed in 20 (43.5%), of whom surgical thrombectomy was performed in 13. The remaining seven patients died before surgery could be performed or their clinical condition was too poor. Apart from one case of wound hematoma (7.7%), post-operative complications that related to the surgical procedure were not observed. Patency of the involved vein was re-established in 12 of the 13 (92.3%) surgically treated patients, and clinical improvement was achieved in 11 (84.6%). In particular, the five patients whose blood cultures revealed Candida species exhibited prompt defervescence after surgical thrombectomy. CONCLUSION Although conservative management is the first therapy of choice in patients with central venous catheter related infected thrombosis, surgical treatment that removes the septic material can be regarded as a last resort in critically ill patients with septic thrombophlebitis that is refractory to conservative management.

Incidence and differential characteristics of culture‐negative fever following pancreas transplantation with anti‐thymocyte globulin induction

Limited data are available on the incidence and characteristics of culture‐negative fever following pancreas transplantation (PTx) with anti‐thymocyte globulin (ATG) induction. Our study aims to better define the features of culture‐negative fever, so it can be delineated from infectious fever, hopefully helping clinicians to guide antibiotic therapy in this high‐risk patient population.

Impact of a preoperative evaluation on the outcomes of an arteriovenous fistula

Purpose The aim of this study was to determine the possible predictors of primary arteriovenous fistula (AVF) failure and examine the impact of a preoperative evaluation on AVF outcomes. Methods A total of 539 patients who underwent assessment for a suitable site for AVF creation by physical examination alone or additional duplex ultrasound were included in this study. Demographics, patient characteristics, and AVF outcomes were analyzed retrospectively. Results AVF creation was proposed in 469 patients (87.0%) according to physical examination alone (351 patients) or additional duplex ultrasound (118 patients); a prosthetic arteriovenous graft was initially placed in the remaining 70 patients (13.0%). Although the primary failure rate was significantly higher in patients assessed by duplex ultrasound (P = 0.001), ultrasound information changed the clinical plan, increasing AVF use for dialysis, in 92 of the 188 patients (48.9%) with an insufficient physical examination. Female sex and diabetes mellitus were risk factors significantly associated with primary AVF failure. Because of different inclusion criteria and a lack of adjustment for baseline differences, Kaplan-Meier survival analysis showed better AVF outcomes in patients assessed by physical examination alone; an insufficient physical examination was the only risk factor significantly associated with AVF outcomes. Conclusion Routine use of duplex ultrasound is not necessary in chronic kidney disease patients with a satisfactory physical examination. Given that female gender and diabetes mellitus are significantly associated with primary AVF failure, duplex ultrasound could be of particular benefit in these subtypes of patients without a sufficient physical examination.

Interpreting CD56+ and CD163+ Infiltrates in Early versus Late Renal Transplant Biopsies

Background: CD56+ and CD163+ cell infiltration in human kidney transplant biopsies have not been fully evaluated. Methods: We investigated the association of CD56+ and CD163+ cell infiltration with human kidney transplant biopsies with antibody- or T-cell-mediated rejection (TCMR) and other histologic lesions. One hundred and seventy four clinically indicated transplant biopsies were included in this analysis. Immunohistochemical staining for C4d, CD56 and CD163 was performed. Results: One hundred and seventy four indication biopsies were divided into early (≤1 year posttransplant; n = 49) and late (>1 year posttransplant; n = 125) biopsies. High numbers of CD56+ cells were uncommon in early biopsies except for those with antibody-mediated rejection (AMR) only. On the other hand, high numbers of CD56+ cells were observed in late biopsies diagnosed as TCMR only, AMR only, and TCMR combined with AMR. In early biopsies, both CD56+ and CD163+ infiltrates correlated strongly with interstitial inflammation, tubulitis, and peritubular capillaritis (ptc) scores. The ci and ct scores, however, were correlated only with the number of CD56+ cells. In late biopsies, on the other hand, the number of CD56+ infiltrates was correlated only with ptc, while the number of CD163+ infiltrates was weakly correlated with any histologic lesion. Multivariable analyses showed that chronic active AMR and the number of CD56+ cells/10 HPF were independently associated with death-censored graft failure post-biopsy. The number of CD163+ cells was not correlated with any pathologic lesion and post-biopsy graft failure. CD56+ infiltrates were also associated with interstitial fibrosis and tubular atrophy. Conclusions: Intragraft CD56+ cell infiltrates were significantly associated with AMR and subsequent poor clinical outcomes.

Long-term Metabolic Outcomes of Functioning Pancreas Transplants in Type 2 Diabetic Recipients.

Background Limited data are available regarding the long-term metabolic outcomes of functioning pancreas transplants in patients with type 2 diabetes mellitus (T2DM). Methods To compare the long-term effects of pancreas transplantation in terms of insulin resistance and &bgr; cell function, comparison of metabolic variables was performed between type 1 diabetes mellitus (T1DM) and T2DM patients from 1-month posttransplant to 5 years using generalized, linear-mixed models for repeated measures. Results Among 217 consecutive patients who underwent pancreas transplantation at our center between August 2004 and January 2015, 193 patients (151 T1DM and 42 T2DM) were included in this study. Throughout the follow-up period, postoperative hemoglobin A1c did not differ significantly between T1DM and T2DM patients, and the levels were constantly below 6% (42 mmol/mol) until 5 years posttransplant, whereas C-peptide was significantly higher in T2DM (P = 0.014). There was no difference in fasting insulin, homeostasis model assessment (HOMA) of insulin resistance, HOMA &bgr; cell, or the insulinogenic index between the groups. Furthermore, fasting insulin and HOMA-insulin resistance steadily decreased in both groups during the follow-up period. Conclusions There was no significant difference in the insulin resistance or &bgr;-cell function after pancreas transplantation between T1DM and T2DM patients. We demonstrated that pancreas transplantation is capable of sustaining favorable endocrine functions for more than 5 years in T2DM recipients.

Analysis of 400 ABO Incompatible Kidney Transplantations : a Single Center Experience

Objectives This study describes the single center experience and long-term results of ABO incompatible kidney transplantation (ABO i KT). Methods 400 patients who received an ABO i KT in the period from February 2009 to December 2016 in Asan Medical Center were retrospectively reviewed. After we experienced lethal infectious complications in the first 89 patients (Era1), a pre-transplantation protocol was modified using lower dose of rituximab, selective use of calcineurin inhibitors and anti-metabolite reduction, and prophylactic strategy(Era2). Results The overall patient survival rates after ABO i KT at 1, 3,and 5 years were 97.9%, 97.4%, and 95.9%.The death censored graft survival rates at 1, 3,and 5 years were 98.9%, 98.1%, and 97.7%. The rejection free graft survival rates at 1, 3,and 5 years were 91.4%, 85.0%, and 82.6%. The overall patient survival rates stratified by era showed a significant difference between era1 and era2 during 5-year follow-up(88.7% vs. 96.7%, P = 0.014) due to infectious complications. Neither was there a significant difference in the 5-year death censored graft survival rates (era1 vs. era2; 98.9% vs. 97.8%, P = 0.85) and the 5-year rejection free graft survival (era1 vs. era2; 85.6% vs. 82.2%, P = 0.34). Infectious complications decreased significantly in era2, including cytomegaloviremia (64.1% vs 30.1%, P < 0.001) and BK viremia ≥ 4logs (15.6% vs 11.3%, P=0.08). Conclusion ABO-incompatible kidney transplantation can be performed safely with a successful graft outcome. Modification of immunosuppression according to host conditions is recommended for the prevention of infectious complications. Figure. No caption available. Figure. No caption available. Figure. No caption available.