Search PubMed⌕ Search

Biomedical subjects

Henkie P Tan

Publications and source records attributed to Henkie P Tan.

17 recordsLinked to original sources
PubMed2006

Alemtuzumab induction and tacrolimus monotherapy in pancreas transplantation: One- and two-year outcomes.

BACKGROUND: Alemtuzumab (Campath-1H) induction with tacrolimus monotherapy has been shown to provide effective immunosuppression for kidney, liver, lung, and small bowel transplantation. This drug combination was evaluated in pancreas transplant recipients. METHODS: Sixty consecutive pancreas transplants (30 simultaneous pancreas-kidney, 20 pancreas after kidney, and 10 pancreas alone) were carried out under this protocol between July 2003 to January 2005. The mean follow-up was 22 months (range 17-33). RESULTS: One-year patient, pancreas, and kidney allograft survival were 95%, 93%, and 90%, respectively. With 22 months follow-up, patient, pancreas, and kidney survival were 94%, 89%, and 87%, respectively. The rejection rate was 30% (18/60), with four patients (7%) experiencing steroid-resistant rejection. Major infection occurred in three (5%) patients resulting in two (3.3%) deaths from disseminated histoplasmosis and a herpes virus infection. One patient with cryptococcal meningitis was successfully treated. Seven (11.7%) patients experienced cytomegalovirus infection, all of whom responded to treatment with ganciclovir. One (1.7%) case of polymorphic posttransplant lymphoproliferative disease was seen, which regressed with a temporary discontinuation of tacrolimus and high-dose ganciclovir. The mean serum creatinine of the 30 simultaneous pancreas-kidney transplants at one year posttransplant was 1.37+/-0.33 mg/ml. The preexisting creatinine in pancreas after kidney transplants was not adversely affected by this immunosuppressive protocol. CONCLUSION: A single dose of perioperative alemtuzumab followed by daily tacrolimus monotherapy provides effective immunosuppression for pancreas transplantation, but the optimal use of this drug combination is not yet clear.

Alemtuzumab↗
PubMed2006

Antilymphoid antibody preconditioning and tacrolimus monotherapy for pediatric kidney transplantation.

OBJECTIVE: Heavy post-transplant immunosuppression may contribute to long-term immunosuppression dependence by subverting tolerogenic mechanisms; thus, we sought to determine if this undesirable consequence could be mitigated by pretransplant lymphoid depletion and minimalistic post-transplant monotherapy. STUDY DESIGN: Lymphoid depletion in 17 unselected pediatric recipients of live (n = 14) or deceased donor kidneys (n = 3) was accomplished with antithymocyte globulin (ATG) (n = 8) or alemtuzumab (n = 9). Tacrolimus was begun post-transplantation with subsequent lengthening of intervals between doses (spaced weaning). Maintenance immunosuppression, morbidity, graft function, and patient/graft survival were collated. RESULTS: Steroids were added temporarily to treat rejection in two patients (both ATG subgroup) or to treat hemolytic anemia in two others. After 16 to 31 months (mean 22), patient and graft survival was 100% and 94%, respectively. The only graft loss was in a nonweaned noncompliant recipient. In the other 16, serum creatinine was 0.85 +/- 0.35 mg/dL and creatinine clearance was 90.8 +/- 22.1 mL/1.73 m2. All 16 patients are on monotherapy (15 tacrolimus, one sirolimus), and 14 receive every other day or 3 times per week doses. There were no wound or other infections. Two patients developed insulin-dependent diabetes. CONCLUSION: The strategy of lymphoid depletion and minimum post-transplant immunosuppression appears safe and effective for pediatric kidney recipients.

Adolescent↗
PubMed2006

Immunosuppressive preconditioning or induction regimens : evidence to date.

The success of solid organ transplantation has been directly related to the development of immunosuppressive drug therapies. Preconditioning or induction therapy was developed to reduce early immunological and nonimmunological renal injury, with the goal of increasing long-term graft survival. However, the routine induction of immunological tolerance to solid organ allograft is currently not achievable because of the morbidity and mortality related to the immunosuppressive regimens themselves. The different therapeutic preconditioning or induction agents and their associated effects on cellular rejection, graft survival outcomes and the need for multiagent post-transplant maintenance therapy are reviewed.

Antilymphocyte Serum↗
PubMed2004

Living-related donor renal transplantation in HIV+ recipients using alemtuzumab preconditioning and steroid-free tacrolimus monotherapy: a single center preliminary experience.

BACKGROUND: End-stage renal disease (ESRD) is an increasing problem in patients infected with the human immunodeficiency virus (HIV). The use of highly active antiretroviral therapy (HAART) has decreased the morbidity associated with HIV and has prompted renewed interest in renal transplantation. METHODS: We performed four cases of deceased donor renal transplantation in HIV+ recipients and three cases where laparoscopic live donor nephrectomy (LLDN) was utilized to obtain the kidney for transplantation into living-related HIV+ recipients. In the four deceased donor cases, conventional tacrolimus-based immunosuppression, without antibody induction was used. In the three living-related cases, the immunosuppressive regimen was based on two principles: recipient pretreatment and minimal posttransplant immunosuppression. Alemtuzumab 30 mg (Campath 1-H) was used for preconditioning followed by low-dose tacrolimus monotherapy. RESULTS: Of the four deceased donor cases, one patient continues to have good graft function, and another is not yet on dialysis but has significant graft dysfunction. Rejection was observed in three patients (75%). Infectious complications occurred in one patient (25%), all non-acquired immunodeficiency syndrome (AIDs) defining. In the three living-related cases, all had good graft function, and none have experienced acute rejection. HIV viral loads remain undetectable. CD4 counts are slowly recovering. No infectious or surgical complications occurred. There were no deaths in either group. CONCLUSIONS: These data suggest that living-related donor renal transplantation with steroid-free tacrolimus monotherapy in a "tolerogenic" regimen can be efficacious. However, long-term follow-up is needed to confirm this observation.

Adult↗
PubMed2004

Pancreatic transplantation at the University of Pittsburgh.

Campath-1H preconditioning with tacrolimus monotherapy is an effective immunosuppressive regimen for pancreas transplantation, with acceptable patient and graft survival rates early after transplantation. Rejection rates are low under this protocol if the tacrolimus level is kept consistently >10 ng/ml. This immunosuppressive protocol, combined with recent technical refinements, has resulted in lower rates of thrombosis and overall complications. Pancreatic transplantation en-bloc with visceral grafts has the following unique features: Diabetes is a rare indication, and HLA matching is not required. The gland is immunologically protected by the simultaneously transplanted visceral organs. Disease gravity, surgical complexity and gut alloimmunity influence the overall pancreatic allograft survival. The current UNOS listing criteria and data registry should be modified for obvious logistic and scientific reasons.

Adolescent↗
PubMed2003

Hypophosphatemia after 95 right-lobe living-donor hepatectomies for liver transplantation is not a significant source of morbidity.

BACKGROUND: Hypophosphatemia appears to be a universal event after right hepatic lobectomy for live-donor adult liver transplantation according to one report. Because hypophosphatemia appears to contribute to increased postoperative complications, routine hyperalimentation with supratherapeutic levels of phosphorus was advocated. METHODS: From July 2000 to May 2002, we performed 95 right-lobe living-donor hepatectomies for 95 adult liver-transplant recipients, the largest single institutional experience. We reviewed our data that were collected prospectively. RESULTS: We did not find profound hypophosphatemia (<1.0 mg/dL) to be prevalent in our donors. At least six (6.3%) donors did not have postoperative hypophosphatemia. In addition, there appears to be no increased morbidity related to hypophosphatemia when aggressively corrected with intravenous or oral phosphates in our group of donors that underwent right-lobe hepatectomies. CONCLUSIONS: We, therefore, cannot endorse the routine administration of hyperalimentation with supratherapeutic phosphorus because of its potential morbidity.

Adult↗
PubMed2003

Hepatic arterial reconstruction in 95 adult right lobe living donor liver transplants: evolution of anastomotic technique.

The success of adult right-lobe living donor liver transplants (RLDLT) would not have been possible without the experience of the early pioneers of pediatric living donor liver transplants (LDLT). Our experience with 95 RLDLTs from July, 2000 to May, 2002 at a single institution is reported with specific emphasis on arterial reconstruction. The evolution of technique using the autogenous Y extension graft and the reverse extension bifurcated graft for arterial revascularization, which we believe has reduced the incidence of hepatic artery thrombosis, is described. Outcome and the incidence of hepatic artery thrombosis are reported.

Adult↗
PubMed2003

Kidney transplantation under a tolerogenic regimen of recipient pretreatment and low-dose postoperative immunosuppression with subsequent weaning.

OBJECTIVE: The purpose of this work was to perform kidney transplantation under a regimen of immunosuppression that facilitates rather than interferes with the recently defined mechanisms of alloengraftment and acquired tolerance. SUMMARY BACKGROUND DATA: In almost all centers, multiple immunosuppressive agents are given in large doses after kidney transplantation in an attempt to reduce the incidence of acute rejection to near zero. With the elucidation of the mechanisms of alloengraftment and acquired tolerance, it was realized that such heavy prophylactic immunosuppression could systematically subvert the clonal exhaustion-deletion that is the seminal mechanism of tolerance. In addition, it has been established that the rejection response can be made more readily treatable by pretransplant immunosuppression. Consequently, we conducted kidney transplantation in compliance with 2 therapeutic principles: recipient pretreatment and the least possible use of posttransplant immunosuppression. METHODS: One-hundred fifty unselected renal transplant recipients with a mean age of 51 +/- 15 years and multiple risk factors had pretreatment with approximately 5 mg/kg of rabbit antithymocyte globulin (Thymoglobulin) in the hours before transplantation, under covering bolus doses of prednisone to prevent cytokine reactions. Minimal posttransplant immunosuppression was with tacrolimus monotherapy to which steroids or other agents were added only for the treatment of rejection. At or after 4 months after transplant, spaced-dose weaning from tacrolimus monotherapy was begun in patients who had exhibited a satisfactory course. RESULTS: One-year actuarial patient and graft survival was 97% and 92%, respectively. Although the incidence of early acute rejection was 37%, only 7% required prolonged treatment with any agent other than tacrolimus. After a follow-up of 6 to 21 months, the mean serum creatinine in patients with functioning grafts is 1.8 +/- 1.0 mg/dL. Seventy-three percent of the patients met the criteria for spaced weaning. Although rejection episodes occasionally required restoration of daily treatment, 94 (63%) of the 150 patients currently receive tacrolimus in spaced doses ranging from every other day to once a week. CONCLUSIONS: With this approach to immunosuppression, it has been possible to avoid early posttransplant overimmunosuppression and thereby to promote the evolution of a degree of partial tolerance sufficient to undertake substantial dose reduction. The strategy, which is applicable for all organ grafts, constitutes a paradigm shift in transplant management at our center.

Adult↗
PubMed2002

Outcome of orthotopic liver transplantation in patients with hepatitis C.

Recurrence of chronic hepatitis C (HCV) after orthotopic liver transplantation (OLT) is universal. The published studies suggest that the short-term outcome is good in these patients, but the long-term prognosis remains unclear. The purpose of this study was to evaluate the outcome of patients with HCV undergoing OLT in a single center and to analyze the risk factors associated with poor outcome. In this retrospective study, we evaluated the outcome of 58 OLT patients with proven HCV who underwent OLT between February 1990 and April 1997 at our institution. The median follow-up time was 36.9 months. Recurrent posttransplant HCV hepatitis was confirmed by liver biochemistry, histology, and persistent HCV RNA in the serum. The patient and graft survival of patients with HCV was compared to that of 42 primary biliary cirrhosis (PBC) and 41 primary sclerosing cholangitis (PSC) patients transplanted during the same period. Following OLT, biochemical evidence of recurrent HCV hepatitis was absent in 46%. Forty percent of patients had recurrent HCV hepatitis and 14% had clinical evidence of recurrent HCV. Thirty-one patients were on cyclosporine, 22 patients on tacrolimus, and 5 patients had cyclosporine switched to tacrolimus or vice versa. The recurrence rate of HCV chronic hepatitis was similar in patients who had cyclosporine (35.5%) or tacrolimus (45.5%) based immunosuppression. Eleven patients (19%) died and five patients (8.6%) were retransplanted for chronic rejection (two), mismatch (one), or primary graft nonfunction (two). The cumulative patient survival rates of one, three, and five years were 94.8%, 84.1%, and 62.2%, respectively. The severity of liver disease progressed with time; 8% of patients developed cirrhosis within two years. The survival rate did not show any relation between HCV recurrence and the type of immunosuppression. In conclusion, although the survival of patients with HCV was not statistically significant compared to those with PBC or PSC, there was a trend towards a lower five-year survival in HCV.

Cholangitis, Sclerosing↗
PubMed2002

Cardiac tamponade in an orthotopic liver recipient with pulmonary hypertension.

OBJECTIVE: To describe the clinical, hemodynamic, and echocardiographic findings of cardiac tamponade in a patient with portopulmonary hypertension shortly after orthotropic liver transplantation. DESIGN: Case report. SETTING: Surgical intensive care unit of a university teaching hospital. PATIENT: One patient with portopulmonary hypertension deteriorated progressively after orthotropic liver transplantation and developed cardiogenic shock. INTERVENTION: Serial transthoracic echocardiography showed increased right ventricular pressures and pericardial effusion without evidence of cardiac tamponade. Since right ventricular diastolic collapse may not be present in the setting of pulmonary hypertension and her clinical scenario was consistent with tamponade, pericardiocentesis was performed. MEASUREMENTS AND MAIN RESULTS: There was dramatic improvement of the clinical, hemodynamic, and echocardiographic variables after pericardiocentesis CONCLUSION: Pulmonary hypertension may decrease the predictive accuracy of echocardiographic clues for cardiac tamponade. Pericardiocentesis should be considered with clinical suspicion of cardiac tamponade without classic echocardiographic evidence in portopulmonary hypertension.

Adult↗