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Featured researches published by C.H.D. Kwon.


Transplantation Proceedings | 2008

Clinical Significance of Posttransplantation Vesicoureteral Reflux During Short-Term Period After Kidney Transplantation

G.O. Jung; Jae Min Chun; J.B. Park; G.S. Choi; C.H.D. Kwon; Jae-Won Joh; S.-K. Lee; S.J. Kim

BACKGROUND Urinary tract infection (UTI) may occur in the form of asymptomatic bacteruria but severe cases may cause life-threatening pyelonephritis or sepsis in immunosuppressed kidney transplant recipients. Vesicoureteral reflux (VUR) is one risk factor in the transplanted kidney. But controversy exists regarding the effect of VUR in terms of graft outcomes. The objective of this study was to analyze the clinical outcomes among patients with posttransplantation VUR. PATIENTS AND METHODS Between April 2005 and June 2006, we examined 75 patients with functioning grafts for more than 1 year by voiding cystourethrography at 1 year for the grade of posttransplantation VUR: group A, absent (n = 28) including grade I (n = 6) and II (n = 22); group B, including grade III (n = 17) and IV (n = 2). Patient characteristics included etiology of end-stage renal disease, duration of dialysis before transplantation, serum creatinine, creatinine clearance at 1 and 12 months after transplantation, and postoperative complications. The presence/absence of UTI, acute rejection, and graft loss were compared for significance. RESULT Posttransplantation VUR present in 47/75 patients (61.3%) was over grade III in 19 patients. There was no difference in significant risk factors between the groups as well as between the reflux subgroups. VUR did not influence graft function with the only significant factor being acute cellular rejection. CONCLUSION We failed to confirm a risk of developing posttransplantation VUR. Posttransplantation VUR did not negatively affect graft function; acute cellular rejection was the only factor that influenced it. Longer follow-up needs to be performed to clarify the long-term effects of posttransplantation VUR on graft function.


Transplantation Proceedings | 2012

Primary Versus Salvage Living Donor Liver Transplantation for Patients With Hepatocellular Carcinoma: Impact of Microvascular Invasion on Survival

J.I. Moon; C.H.D. Kwon; Jae-Won Joh; G.S. Choi; G.O. Jung; J.M. Kim; M. Shin; Suk-Joo Choi; S.J. Kim; S.-K. Lee

OBJECTIVE Salvage liver transplantation (LT) has been proposed for patients with a small hepatocellular carcinoma (HCC) and preserved liver function. Few reports have been issued on salvage LT in a living-donor (LD) LT setting. Therefore, we performed this study to evaluate differences in tumor invasiveness and other risk factors on survival after salvage versus primary LDLT. METHODS Between September 1996 and December 2008, 324 patients with HCC underwent LT. We excluded 138 patient from the analysis, leaving 186 HCC patients for analysis, including 17 (9.1%) who had undergone earlier resection, the salvage LDLT cohort. The other 169 patients underwent primary LDLT. RESULTS Intrahepatic metastasis, Edmonson-Steiner histologic grade, microscopic vascular invasion, and preoperative serum alpha-fetoprotein levels significantly influenced tumor recurrence. Microscopic vascular invasion, intrahepatic metastasis, Edmonson-Steiner histologic grade, and treatment by salvage LDLT were significantly associated with poor patient survival univariate analysis. However, only microscopic vascular invasion was significant on multivariate analysis. The treatment modality (primary or salvage LDLT) was not observed to affect overall or disease-free survival significantly on multivariate analysis. Disease-free survival was significantly better in the primary than in the salvage LDLT group. Furthermore, patients in the primary LDLT group tended to show better survival. However, when stratified by the presence or absence of microscopic vascular invasion, no significant group difference was found for overall or disease-free survival among those without versus with microscopic vascular invasion. CONCLUSIONS Five-year overall survival after primary versus salvage LDLT were similar when differences in tumor pathologic features, such as microscopic vascular invasion, were taken into account. Multivariate analysis showed that the treatment itself was not a significant prognostic factor for survival.


Transplantation Proceedings | 2008

Renal Transplantation in Patients With a Small Bladder

Jae Min Chun; G.O. Jung; J.B. Park; G.S. Choi; C.H.D. Kwon; Jae-Won Joh; S.-K. Lee; S.J. Kim

BACKGROUND In patients undergoing kidney transplantation with a small bladder, many surgeons are faced with technical difficulties about the implantation as well as about satisfactory bladder rehabilitation. The objective of this study was to clarify the clinical outcomes of patients with end-stage renal disease who had a bladder capacity of less than 100 mL on preoperative voiding cystourethrogram after renal transplantation using extravesical ureteroneocystostomy. PATIENTS AND METHODS We retrospectively studied 345 patients with end-stage renal disease who underwent renal transplantation between April 2002 and June 2006. These patients were classified into two groups according to their preoperatively estimated bladder capacity using a voiding cystourethrogram. Group A had a bladder capacity of less than 100 mL (n = 23; 6.7%) and group B had a capacity of 100 mL or more (n = 322; 93.3%). For each group, the clinical outcome, including serum creatinine level at 1 month and 1 year after transplantation, bladder capacity, surgical complications, and prevalence of urinary tract infection (UTI) requiring hospital admission were recorded and the graft survival rate calculated. RESULTS Compared with group B, group A had undergone a longer duration of dialysis and required cadaveric kidney transplantation more frequently (P < .05). Postoperative surgical complications occurred in nine cases. There was no difference in the frequency of surgical complications and UTI requiring hospital admission between group A and group B. At 1 year posttransplant, bladder capacity was 342.0 +/- 43.8 mL (range, 300-400 mL) and 429.1 +/- 75.9 mL (range, 200-500 mL), respectively (P = .015). There was no statistical difference between the groups in the serum creatinine level and the graft survival rate at 5 years after transplantation (100% vs 92.4%). CONCLUSIONS Similar to patients with a normal bladder size, renal transplantation can be successfully achieved in patients with a small bladder. Attempts to increase the bladder capacity by programmed training of the bladder and bladder expansion by surgical intervention seem unnecessary.


Transplantation Proceedings | 2010

Living Donor Liver Transplantation in Budd-Chiari Syndrome: A Single-Center Experience

G.S. Choi; J.B. Park; G.O. Jung; Jae Min Chun; J.M. Kim; J.I. Moon; C.H.D. Kwon; S.J. Kim; Jae-Won Joh; S.-K. Lee

Budd-Chiari syndrome (BCS), which is characterized by hepatic venous outflow obstruction due to occlusion of the major hepatic vein and/or the inferior vena cava (IVC), is rare. Traditionally, a caval resection is advocated for these patients; however, such a maneuver renders living donor liver transplantation (LDLT) impossible. We encountered BCS in 4/377 LDLT patients during a 5-year period (January 2003 to December 2007). This report examine the various surgical modifications in these 4 patients, who underwent to LDLT for BCS. Resection of right hepatic vein (RHV) with an adjacent fibrotic part of the IVC with direct anastomosis of the graft RHV to the IVC was performed in 2 patients. One patient underwent retrohepatic IVC excision and reconstruction with a cryopreserved autologous IVC graft. The fourth patient, with a preexisting mesoatrial shunt for BCS, underwent conversion of this to a RHV atrial shunt. Graft and patient survivals were 100%. There were few complications in either donors or recipients. LDLT for BCS can be performed safely with adequate venous drainage techniques and with anticoagulant therapy and good follow-up for early diagnosis and treatment of recurrence leading to excellent long-term results.


Transplantation Proceedings | 2010

The Risk Factors of Delayed Graft Function and Comparison of Clinical Outcomes After Deceased Donor Kidney Transplantation: Single-Center Study

G.O. Jung; M.R. Yoon; S.J. Kim; M.J. Sin; Eun-Sang Kim; J.I. Moon; J.M. Kim; G.S. Choi; C.H.D. Kwon; Jin Whan Cho; S.-K. Lee

INTRODUCTION The aim of this study was to analyze risk factors for delayed graft function (DGF) after deceased donor kidney transplantation and to compare the clinical outcomes of non-DGF versus DGF recipients. PATIENTS AND METHODS From January 2004 to June 2008, 75/154 kidneys were transplanted into 74 recipients. We classified the recipients into two groups: group 1 (n=61) without DGF and group 2 (n=13) with DGF. RESULTS On univariate analysis, recipient age (P=.048) cause of brain death (traumatic brain injury vs disease, P=.016), blood urea nitrogen (P=.002), serum creatinine (P=.001), arterial pH (P=.019), and serum sodium level (P=.012) just before organ procurement showed significant differences. On multivariate analysis, the cause of brain death (P=.015, hazard ratio [HR]: 7.086), the terminal serum creatinine>or=1.5 mg/dL before organ procurement (P=.007, HR: 10.132), and recipient age over >or=50 years (P=.021, HR: 7.767) were independent risk factors for the development of DGF. Graft failures occurred among 5/74 recipients with 5-year graft survivals between group 1 and group 2 of 91.7% and 84.6%, respectively. Patient death occurred in five cases, most by due to infection. The 5-year patient survival between groups 1 and 2 were 93.9% and 84.6%, respectively (P = .106). CONCLUSION The independent risk factors for DGF were the cause of brain death, the terminal creatinine level, and the recipient age. In deceased donor kidney transplantation, DGF may have less effect on long-term patient and graft survivals.


Transplantation Proceedings | 2010

Can Preemptive Kidney Transplantation Guarantee Longer Graft Survival in Living-Donor Kidney Transplantation? Single-Center Study

G.O. Jung; J.I. Moon; J.M. Kim; G.S. Choi; C.H.D. Kwon; Jin Whan Cho; S.J. Kim

INTRODUCTION The benefit of preemptive kidney transplantation (KTx) for graft survival compared with nonpreemptive KTx is controversial. OBJECTIVE To analyze the influence of preemptive KTx on graft survival. PATIENTS AND METHODS The study included 476 of 531 patients who had undergone living-donor KTx between January 2000 and June 2007. Pediatric patients and those who had previously undergone KTx were excluded. Recipients were divided into 2 groups; group 1 included 413 patients (86.8%) who received grafts after institution of maintenance dialysis, and group 2 included 63 patients (13.2%) who underwent preemptive KTx. RESULTS Donor type and HLA mismatch demonstrated significant differences between the 2 groups. Group 1 had more living donors and fewer HLA mismatches. Warm ischemia time in group 2 was significantly shorter than in group 1. The serum creatinine concentration in group 1 on postoperative day 7 was significantly higher than in group 2. Five- and 10-year graft survival in groups 1 and 2, respectively, were 95.3% and 81.3% vs 92.9% and 92.9%. Graft survival was not significant insofar as duration and method of dialysis. At our institution, independent risk factors for graft survival in living-donor KTx are primary end-stage renal disease, acute cellular rejection episodes, and recipient age. CONCLUSION We observed no benefit on graft survival in recipients of living-donor KTx insofar as whether they had undergone previous dialysis.


Transplantation Proceedings | 2010

Risk factors for posttransplant lymphoproliferative disorder in pediatric liver transplant recipients with cytomegalovirus antigenemia.

J.M. Kim; S.-K. Lee; S.J. Kim; Jae-Won Joh; C.H.D. Kwon; Yon-Ho Choe; Milljae Shin; Eun-Sang Kim; J.I. Moon; G.O. Jung; G.S. Choi

Epstein-Barr virus (EBV) infections, associated with posttransplant lymphoproliferative disorder (PTLD) are known to develop in cytomegalovirus (CMV)-infected transplant recipients due to the indirect effects of CMV. This study evaluated risk factors for PTLD among pediatric liver transplant recipients with CMV infections. We reviewed the medical records of 119 patients<or=18 years old who underwent liver transplantation between September 1996 and April 2009. Sixty-six subjects (55.5%) displayed CMV antigenemia during the study period; 15 (12.6%) developed PTLD. Of these, 10 developed PTLD after CMV antigenemia. The other patients (n=5) were excluded due to negative CMV antigenemia. The incidence of PTLD influenced by CMV infection was not significantly different from the incidence of PTLD without underlying CMV (P=.258). There were no differences in age, gender, antiviral prophylaxis, type of liver transplantation, or acute rejection episodes in the incidence of between patients with versus without PTLD. EBV but not CMV high-risk groups were a predictor for the development of PTLD (P=.035). CMV syndrome, tissue-invasive CMV disease, and CMV peak titer were not associated with an increased risk of PTLD. The primary risk factor for PTLD was EBV high-risk patients (donor positive/recipient negative). CMV disease was not associated with PTLD in pediatric liver transplant recipients with CMV infections.


11th Congress of the Asian Society of Transplantation, Habtoor Grand Hotel, Beirut, Lebanon. | 2010

Comparison of Outcomes of Living and Deceased Donor Kidney Grafts Surviving Longer Than 5 Years in Korea

S. Lee; Jung-Han Kim; M. Shin; Eun-Sang Kim; J.I. Moon; G.O. Jung; G.S. Choi; C.H.D. Kwon; Jae-Won Joh; S.J. Kim

BACKGROUND It is generally recognized that living donor kidney transplantation (LDKT) grafts are superior to deceased donor kidney transplantation (DDKT) grafts. We compared survival and functional outcomes of LDKT and DDKT grafts. METHODS Among 1000 kidneys transplanted from 1995 to 2008, we selected grafts surviving >5 years, excluding pediatric, multi-organ transplantation, and retransplantations (n=454). RESULTS There were 179 kidneys from deceased donors and 275 from living donors. Recipients showed no difference in age, gender, or cause of renal failure. Donors were younger in the DDKT group (30.6 vs 38.5 years; P<.05). There were more male donors in the DDKT group (73.2% vs 54.5%; P<.05). Deceased donors showed a greater mean number of HLA mismatches (4.2 vs 2.7; P<.05). Death-censored graft survival at 10 years showed no difference (DDKT 88.9% vs LDKT 88.9%; P=.99). Mean serum creatinine at 5 years was 1.41 mg/dL for DDKT and 1.44 mg/dL for LDKT (P=.75). Mean estimated glomerular filtration rate at 5 years was 67.8 mL/min/1.73 m2 for DDKT and 62.1 mL/min/1.73 m2 for LDKT (P=.23). Twenty-three DDKT grafts (12.8%) and 47 LDKT grafts (17.1%) experienced acute rejection episodes (P=.22). DDKT recipients showed more cases of viral and bacterial infections compared with LDKT recipients (viral, 11.7% vs 2.2% [P<.05]; bacterial, 21.8% vs 7.3% [P<.05]). CONCLUSION Among kidney grafts surviving >5 years, there was no difference in survival or serum creatinine levels at 5 and 10 years between DDKT and LDKT grafts.


Transplantation Proceedings | 2012

Effectiveness of Locoregional Therapy Before Living Donor Liver Transplantation in Patients With Hepatocellular Carcinoma Who Meet the Milan Criteria

J.M. Kim; C.H.D. Kwon; Jae-Won Joh; Min-Gew Choi; Lee Jh; Koh Kc; S.W. Paik; Gyuri Kim; S.J. Kim; S.-K. Lee; Byung-Su Yoo

BACKGROUND Many patients are diagnosed with hepatocellular carcinoma (HCC) within the Milan criteria. In Korea, these patients are preferentially treated with locoregional therapy (LRT) instead of living donor liver transplantation. We investigated the effectiveness of LRT in liver transplant recipients who met the Milan criteria at the time of HCC diagnosis and investigated risk factors for HCC recurrence. METHODS We retrospectively reviewed the medical records of patients diagnosed with HCC who met the Milan criteria between 2002 and 2008. RESULTS We performed 101 liver transplants for HCC during the study period. Seventy-one patients (70%) underwent pretransplant LRT. The disease-free survival rates at 1, 3, and 5 years in patients who received LRT were 96.6%, 93.1%, and 93.1%, and in those who did not receive LRT, 94.2%, 83.4%, and 83.4%, respectively. There were no differences between the 2 groups. Multivariate analysis showed that a low Model for End-Stage Liver Disease (MELD) score and microvascular invasion were independent predictors of HCC recurrence after transplantation. The MELD scores and rate of microvascular invasion were not statistically different in patients with or without previous LRT. CONCLUSION Pretransplant LRT for patients with HCC who met the Milan criteria at the time of diagnosis did not provide a clear benefit with respect to HCC recurrence after transplantation. If patients have suitable living donors, those who meet the Milan criteria should undergo a liver transplantation as soon as possible.


Transplantation proceedings | 2012

Effectiveness of Intraportal Prostaglandin E1 Administration after Liver Transplantation

M. Shin; Sanghyun Song; J.M. Kim; S.J. Kim; Jae-Won Joh; S.-K. Lee; C.H.D. Kwon

PURPOSE Prostaglandin E1 (PGE1) has been used to improve hepatic blood flow and to reduce ischemia reperfusion injuries of allografts in liver transplantation. However, PGE1 undergoes extensive metabolic clearance in the pulmonary and splanchnic circulation during intravenous administration. We analyzed the effect of intraportally administered PGE1. METHODS Sixty living-donor liver transplant recipients received continuous infusions of PGE1 for 10 days immediately after the reperfusion of the allografts. Of them, 40 recipients received PGE1 intravenously (IV group) via the internal jugular vein, and 20 recipients received PGE1 intraportally (IP group) through a catheter in the inferior mesenteric vein. Data were collected for 3 weeks postoperatively. RESULTS The IP group exhibited lower initial aspartate aminotransferase and alanine aminotransferase levels compared with the IV group. However, no apparent differences were recognized in the serum albumin, total bilirubin, alkaline phosphatase, r-glutamyl transpeptidase, or prothrombin time levels between the 2 groups. Chylorous ascites were observed more frequently in the IP group. There was no difference in portal venous flow measured by Doppler sonogram between the 2 groups during the first postoperative week. CONCLUSION This study demonstrated that intraportal administration of PGE1 had a better cytoprotective effect against hepatocellular damage than intravenous administration, although it did not have additional benefits for perihepatic hemodynamics.

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S.J. Kim

Samsung Medical Center

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S.-K. Lee

Samsung Medical Center

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J.M. Kim

Samsung Medical Center

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Jae-Won Joh

Samsung Medical Center

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G.S. Choi

Samsung Medical Center

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M. Shin

Samsung Medical Center

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J.B. Park

Samsung Medical Center

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J.-W. Joh

Samsung Medical Center

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G.O. Jung

Samsung Medical Center

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J.I. Moon

Samsung Medical Center

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