S R Choi

Catholic University of Korea, Sŏul, Seoul, South Korea

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Publications (5)4.76 Total impact

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    ABSTRACT: Graft nephrectomy is the last-resort option for renal transplant recipients. The aim of this study was to compare the clinical characteristics of patients who underwent graft nephrectomy according to the time after renal transplantation. From 2005 to 2012, 42 patients underwent graft nephrectomy after transplant failure. We divided these patients into early (n = 17) and late graft nephrectomy (n = 25) groups based on graft survival to 6 months, comparing their causes for nephrectomy and clinical characteristics. The patients included 29 men and 13 women, with an overall mean age of 45 years (range, 10-71 years). The main causes for early and late graft nephrectomy were irreversible acute rejection (71%) and graft intolerance syndrome (95%), respectively. The clinical characteristics did not significantly differ between the early and late graft nephrectomy groups except for operative-related complications. Bleeding was more common among patients who underwent early (n = 10) versus late (n = 3) graft nephrectomy (59% vs 12%; P = .01). Of the 10 patients with perioperative bleeding, 8 had a bleeding tendency, such as low platelet count or prolonged prothrombin time at the time of the operation. These complications occurred after antirejection therapy involving plasma exchange or antithymocyte globulin treatment. Allograft nephrectomy was associated with a mortality rate of 2.38%. The cause for graft nephrectomy and type of perioperative complication differed according to timing of graft nephrectomy. Antirejection therapy appeared to contribute to postoperative complications such as bleeding.
    Transplantation Proceedings 10/2013; 45(8):2953-6. · 0.95 Impact Factor
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    ABSTRACT: The aim of this study was to evaluate whether 3-dimensional computerized tomographic angiography (3D-CTA) is useful to detect transplant renal artery stenosis (TRAS). Fourteen patients with clinically suspected TRAS underwent color Doppler ultrasonography (CDU) and 3D-CTA before renal angiography. We compared 3D-CTA and CDU for accuracy based on the results of renal angiography. The safety of 3D-CTA was investigated by measuring the estimated glomerular filtration rate (eGFR) before and after the 3D-CTA examination. The 10 men and 4 women who participated in this study showed a mean eGFR of 75 mL/min/1.73 m(2) (range 60-94). Of these, 9 patients were diagnosed with TRAS. 3D-CTA detected stenoses in all 9 patients, but CDU failed to detect it in 3, including, 2 with end-to-side arterial anastomoses, which may be more challenging to detect compared with end-to-end anastomoses. The stenotic area in 3D-CTA was similar to that detected by renal angiography (70 ± 12 vs 68 ± 11). The eGFR did not differ significantly before versus after the 3D-CTA examination; 72 ± 13 vs 69 ± 14 mL/min/1.73 m(2). 3D-CTA was an effective safe method to detect renal artery stenosis among transplant recipients with an eGFR >60 mL/min/1.73 m(2).
    Transplantation Proceedings 04/2012; 44(3):691-3. · 0.95 Impact Factor
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    ABSTRACT: There are no definite guidelines about donation among prospective donors with asymptomatic urinary abnormalities. We evaluated the pathology of prospective kidney donors with asymptomatic urinary abnormalities and assessed the clinical outcomes of their organs. We reviewed the medical records of 15 prospective kidney donors who underwent kidney biopsy. We evaluated the role of kidney biopsy in terms of graft function, protocol biopsy, and follow-up biopsy. We further assessed the clinical outcomes of donors and recipients. Thin basement membrane nephropathy (TBMN) is the most common cause of the persistent microscopic hematuria (n = 7; 50%), followed by nonspecific findings (n = 4; 29%), IgA nephropathy (n = 2; 14%), and focal segmental glomerulosclerosis (n = 1; 7%). Of the 14 candidate donors with persistent microscopic hematuria, 9 were accepted as kidney donors: 5 with TBMN, 3 with mild mesangiopathy, and 1 with nonspecific interstitial changes. The function of the 9 grafts was relatively stable (mean serum creatinine level 2.38 mg/dL) over a mean follow-up of 57 months. Graft failure that developed in 2 grafts was not associated with biopsy findings: acute rejection and patient death with a functioning graft. Interestingly, basement membrane thickness in 2 allografts from donors with TBMN appeared normal by electron microscopy follow-up biopsy; the allografts did not show hematuria. Moreover, the clinical outcomes of donors were favorable (mean serum creatinine 0.94 ± 0.32 mg/dL) during the mean follow-up period of 34.7 ± 42.5 months. We did not observe new-onset hypertension or proteinuria in donors. Kidney biopsy in prospective kidney donors with urinary abnormalities is a safe and effective diagnostic procedure to stratify candidates. Therefore, kidney biopsy should be actively performed to improve the prognosis of both donors and recipients.
    Transplantation Proceedings 01/2012; 44(1):11-3. · 0.95 Impact Factor
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    ABSTRACT: Delayed graft function (DGF), a dialysis requirement within a week after transplantation, can occur in deceased-donor renal transplantation. DGF is rare, in living-donor renal transplantation (LDRT) and its incidence and risk factors have not been established. We investigated the incidence and clinical characteristics of DGF in LDRT over 10 years. We compared HLA mismatches, panel reactive antibody status, frequency of nonrelated donors, donor age, sex match, recipient-donor body weight ratio, total ischemia time, and transplanted kidney weight between DGF and non-DGF patients. The incidence of DGF in LDRT was 1.6%, which differed from earlier reports. HLA mismatch, female recipient frequency, and nonrelated donors were higher among the DGF group, but no risk factor for DGF was significant after multivariate logistic regression analysis. Biopsy findings showed 2 cases to be associated with rejection, 1 with acute pyelonephritis and 1 with acute tubular necrosis. The cases with rejection resulted in graft failure within 3 years after transplantation, but the other cases were followed with favorable graft function. The incidence of DGF among LDRT was lower than that reported earlier studies, and the factors previously reported to cause DGF were not associated with DGF herein. Because DGF with rejection responses has a poor prognosis, strenuous strategies, including biopsy, should be performed in cases of DGF after LDRT.
    Transplantation Proceedings 01/2012; 44(1):43-6. · 0.95 Impact Factor
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    ABSTRACT: Chronic active antibody-mediated rejection (CAMR) is an important cause of chronic kidney allograft dysfunction, but there has been no effective treatment protocol established for it. Six renal transplant recipients who showed progressive deterioration in graft function and CAMR as diagnosed by biopsy were enrolled. We administered a single dose of rituximab (375 mg/m(2)), followed by intravenous immunoglobulin (IVIg, 0.4 g/kg) for 4 days. The efficacy of this protocol was assessed on the basis of the improvement in allograft function, the amount of proteinuria, and the change in donor-specific antibodies (DSAs). We categorized the patients into 2 groups, responders and nonresponders, according to their response to the treatment. All of the patients showed progressive deterioration of graft function before the diagnosis of CAMR. Luminex solid-phase assays showed that 3 patients had DSAs. After the treatment, allograft function improved or stabilized in 3 patients in the responder group, but still showed a deteriorating pattern in the nonresponder group. In the responder group, the amount of proteinuria also decreased after the treatment, but it increased in the nonresponder group. On diagnosis of CAMR, the nonresponders showed a longer posttransplantation period, a higher degree of transplant glomerulopathy, more severely deteriorated allograft function, and higher proteinuria compared with the responders. The combination of rituximab and IVIg was effective in early-stage CAMR, but the effect was limited in the advanced stage.
    Transplantation Proceedings 01/2012; 44(1):182-4. · 0.95 Impact Factor