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D W Hanto

Publications and source records attributed to D W Hanto.

At least 19 recordsLinked to original sources
PubMed2006

Retransplantation after post-transplant lymphoproliferative disorders: an OPTN/UNOS database analysis.

Post-transplant lymphoproliferative disorders (PTLD) are a life-threatening complication of immunosuppressive therapy. Retransplantation of survivors remains controversial. The Organ Procurement and Transplant Network/United Network for Organ Sharing database was reviewed for individuals who developed PTLD and underwent retransplant from 1987 through 2004. Sixty-nine retransplants have been performed: 27 kidney, 22 liver, 9 lung, 6 heart, 4 intestine and 1 pancreas. At first transplant, most subjects (63.8%) were <17 years of age and was similar at retransplant with 50.7% less than 17 years. Time from transplant to PTLD was <1 year in 33.3%, 1-3 years in 21.7%, 3-5 years in 21.7%, 5-10 years in 21.7% and >10 years in 1.4%. Time from PTLD to retransplant was <1 year in 24.6%, 1-3 years in 37.7%, 3-5 years in 17.4% and 5-10 years in 20.3%. Induction agents were used in 21.7% of first and 47.8% of retransplants. Immunosuppression for first transplant was cyclosporine (CSA) in 55.1%, tacrolimus (TAC) in 27.5% versus CSA in 26.1%, TAC in 66.7% of retransplants. At last follow-up, patient and graft survival are 85.5% and 73.9%, respectively. Most subjects retransplanted after PTLD are <17 years on TAC-based immunosuppression. Patient/graft survival is excellent and retransplantation in PTLD subjects should be considered acceptable.

Databases, Factual↗
PubMed2005

Severe hypoglycaemia post-gastric bypass requiring partial pancreatectomy: evidence for inappropriate insulin secretion and pancreatic islet hyperplasia.

AIMS/HYPOTHESIS: Postprandial hypoglycaemia following gastric bypass for obesity is considered a late manifestation of the dumping syndrome and can usually be managed with dietary modification. We investigated three patients with severe postprandial hypoglycaemia and hyperinsulinaemia unresponsive to diet, octreotide and diazoxide with the aim of elucidating the pathological mechanisms involved. METHODS: Glucose, insulin, and C-peptide were measured in the fasting and postprandial state, and insulin secretion was assessed following selective intra-arterial calcium injection. Pancreas histopathology was assessed in all three patients. RESULTS: All three patients had evidence of severe postprandial hyperinsulinaemia and hypoglycaemia. In one patient, reversal of gastric bypass was ineffective in reversing hypoglycaemia. All three patients ultimately required partial pancreatectomy for control of neuroglycopenia; pancreas pathology of all patients revealed diffuse islet hyperplasia and expansion of beta cell mass. CONCLUSIONS/INTERPRETATION: These findings suggest that gastric bypass-induced weight loss may unmask an underlying beta cell defect or contribute to pathological islet hyperplasia, perhaps via glucagon-like peptide 1-mediated pathways.

Adult↗
PubMed2005

The significance and clinical factors associated with a subcentimeter resection of colorectal liver metastases.

BACKGROUND: Prognosis after resection of colorectal liver metastases is influenced by various factors. A positive margin of resection (MOR) has been shown to adversely influence prognosis. Although a 1-cm MOR has been accepted as adequate, the data to support this guideline are sparse. METHODS: Our hepatobiliary database was queried for patients who underwent liver resection for colorectal metastases between January 1992 and July 2003. All patients were divided into three groups: MOR <.5 cm (group A), .5 to 1 cm (group B), and >1 cm (group C). Operative reports from each hepatic resection were analyzed to determine local factors that may have contributed to a subcentimeter MOR. RESULTS: A total of 112 patients (67 men and 45 women) underwent liver resection for colorectal metastases with negative margins. Fifty-three patients were in group A, 26 patients were in group B, and 33 patients were in group C. Group C demonstrated decreased local recurrence (LR; P = .003), distant recurrence (DR; P = .008), and disease-free recurrence (P = .002). A significant difference in the overall time to LR (P = .003), time to DR (P = .003), and disease-free survival (P = .002) was also demonstrated. Factors associated with a subcentimeter MOR included nonanatomical resection (P = .043), proximity to a major vessel (P = .003), and central location (P = .002). CONCLUSIONS: A <1-cm resection for colorectal liver metastases is associated with increased LR and DR, as well as decreased disease-free survival. When a nonanatomical resection is performed, a MOR >1 cm should be attempted, because an adequate margin is often underestimated. Considerations should be made for extended resections when tumors are centrally located or near major vessels.

Aged↗
PubMed2001

A single center experience with extrahepatic cholangiocarcinomas.

BACKGROUND: Few large Western series on cholangiocarcinoma have been reported in the literature. We reviewed 40 consecutive cases of extrahepatic cholangiocarcinomas referred to a single center. METHODS: From 1992 until 2000, 40 patients with extrahepatic cholangiocarcinomas were evaluated. The charts of all patients were reviewed to evaluate predictors of survival. Survival was calculated with the Kaplan-Meier method. RESULTS: Forty patients were referred for management of extrahepatic cholangiocarcinomas. Tumors were located in the distal common duct in 3 (7.5%), mid duct in 5 (12.5%), and at the bifurcation in 32 (80%). Surgical resection was attempted in 32 (80%) patients and was curative in 9 (22.5%), palliative in 11 (27.5%), and diagnostic in 12 (30%). Mean survival for all patients was 21.1 +/- 5.1 months and on the basis of tumor stage was 71.4 +/- 15.4, 39.7 +/- 10.6, 19.2 +/- 2.9, 3.9 +/- 1.8, and 6.9 +/- 1.3 months for stages I, II, III, IVA, and IVB, respectively. Mean survival was 51.1 +/- 13.5 months versus 10 +/- 1.8 months in those with curative and noncurative resections, respectively. The presence of a portal mass was associated with a reduction in mean survival from 28.4 +/- 7.2 months to 6.0 +/- 1.9 months. CONCLUSIONS: Extrahepatic cholangiocarcinoma remains a dismal disease with only a 22.5% chance of a curative surgical resection, achieving a 5-year survival rate of 44.4%. Only the absence of a portal mass was predictive of a possible curative resection and long-term survival.

Bile Duct Neoplasms↗
PubMed2000

Long-term results of surgical repair of bile duct injuries following laparoscopic cholecystectomy.

BACKGROUND: Laparoscopic cholecystectomy (LC) is associated with an increased incidence of bile duct injuries when compared with the open surgical technique. Long-term results of repaired injuries and hepatic damage associated with chronic biliary obstruction are lacking. METHODS: From Aug 1, 1991 until Dec 1, 1999, there were 27 patients referred for management of complex biliary injuries that occurred during LC. Patients underwent percutaneous transhepatic cholangiography and placement of transhepatic catheters with computed tomography-guided biloma drainage when indicated. On the basis of the cholangiography findings, patients underwent Roux-en-Y hepaticojejunostomy (HJ) and liver biopsy or were treated with nonsurgical interventions. RESULTS: Twenty-one of 27 patients (77. 8%) underwent HJ, and 16 of these 21 patients (76.2%) also underwent hepatic biopsy. In 1 patient, a recurrent stricture developed at 20 months after the initial repair; and, in a second patient, an episode of cholangitis developed in the postoperative period with the transhepatic catheters in place. Five of 16 patients (31.2%) demonstrated marked hepatic fibrosis with 4 (25%) of these patients showing evidence of evolving cirrhosis at the time of HJ. CONCLUSIONS: In this series with 55 months of follow-up, HJ repair of LC injuries was associated with an initial 95.2% success rate and an ultimate success rate of 100%. Despite this, delayed referral, averaging 12 months, was associated with significant hepatic injury in 5 of 16 (31.3%) patients who underwent biopsy.

Adolescent↗
PubMed1999

Microsatellite instability is absent in liver and biliary mucosa of patients with primary sclerosing cholangitis.

Microsatellite instability occurs in the colonic mucosa of patients with inflammatory bowel disease and may predispose the mucosa to neoplastic transformation. It is unknown whether microsatellite instability also plays a role in the neoplastic risk associated with primary sclerosing cholangitis. We examined 134 tissue samples from 21 patients with sclerosing cholangitis for microsatellite instability at eight loci. All tissues were also stained immunohistochemically using an antibody to the proliferation marker Ki-67. Microsatellite instability did not occur in any samples from the intrahepatic or extrahepatic biliary system, although one patient demonstrated instability in the colon. Ki-67 indices ranged from 0 to 2.5 in nondysplastic biliary epithelium and from 1.5 to 29.4 in areas of dysplasia. The absence of microsatellite instability in sclerosing cholangitis suggests that the genetic basis of neoplastic progression in chronic inflammatory disease of the bile ducts differs from that of intestinal cancers arising in the setting of chronic inflammatory bowel disease and may relate to differences in the microenvironment in these two sites.

Adult↗
PubMed1999

Addisonian crisis in a liver transplant patient due to fluconazole withdrawal.

Fluconazole is an antifungal agent commonly used in liver transplant patients. In addition to its antifungal activity, it is a potent inhibitor of the liver cytochrome P450 enzymes. These enzymes degrade a wide range of metabolically active compounds including glucocorticoids. In this report, we identify an episode of Addisonian crisis that occurred in a liver transplant patient receiving prednisone immunosuppression after fluconazole was discontinued. We postulate the mechanism for the crisis was a reversal of the fluconazole-induced suppression of the P450 enzymes. The resulting increased activity altered the patient's glucocorticoid metabolism leading to an Addisonian crisis.

Addison Disease↗
PubMed1998

Use of low-dose OKT3 as induction therapy in liver transplantation.

BACKGROUND: A pilot study was performed to prospectively evaluate the safety and efficacy of "low-dose" OKT3 induction after liver transplantation. METHODS: Sixteen patients received a 5- to 10-day course of OKT3 (2.5 mg i.v. daily) along with azathioprine, prednisone, and the delayed introduction of cyclosporine (Neoral). RESULTS: Patient and graft survival rates at 1 year were 88% and 82%. Five patients (31%) had biopsy-proven rejection; all five were treated successfully with steroids. There were 15 infections in 12 patients, including 5 cytomegalovirus infections. Adverse events attributed to OKT3 consisted of low-grade fever (five patients), transient hypoxemia (three patients), and transient hypotension (two patients). Pharmacy acquisition costs for OKT3 averaged $2,139 less as compared to a group of historical controls receiving full-dose therapy. CONCLUSIONS: Low-dose OKT3 induction appears to be a safe and useful method of postoperative immunosuppression after liver transplantation. Its ultimate clinical, immunologic, and economic efficacy awaits determination by randomized trial.

Adult↗
PubMed1998

Transplantation.

Explore the source record for details and available documents.

Graft Rejection↗
PubMed1998

Peritoneal metastasis of intracranial glioblastoma via a ventriculoperitoneal shunt preventing organ retrieval: case report and review of the literature.

The case of patient with glioblastoma metastatic to the peritoneal cavity 9 months after ventriculoperitoneal shunt surgery precluding cadaver organ procurement is presented. Even though central nervous tumors rarely metastasize spontaneously, the literature indicates that systemic metastases are related to previous surgical procedures and especially shunt surgery. Central nervous tumors have been known to metastasize to lungs, liver, and kidneys and could be transmitted through transplanted organs as shown in the Cincinnati tumor registry. The transplant surgeon should be alerted to this possibility and thorough search for metastases should be undertaken before considering primary brain tumor patients as donors.

Adolescent↗
PubMed1997

Cost analysis of intraoperative blood salvage during orthotopic liver transplantation.

Approximately 6,000 to 7,000 orthotopic liver transplantation (OLT) procedures are performed annually, which require the administration of large volumes of blood products. Thus liver transplantation can significantly strain local and regional blood resources at a time when transfusion practices are changing dramatically, in large part because of anxiety caused by the human immunodeficiency virus. Intraoperative autologous transfusion has been proposed as a means of both reducing transfusion demands and lessening the hazards of allogeneic transfusion. However, the cost effectiveness of intraoperative blood salvage has not been unequivocally determined. We retrospectively examined the cost of intraoperative autologous transfusion during OLT for a 2-year period at the University of Cincinnati Hospital. A direct comparison was made between the charge for autologous transfusion and the calculated cost of allogeneic transfusion. Seventy OLT procedures were performed during the years 1993-1994. The average charge for autologous transfusion was $1,048.73 per case. Cell-salvage volumes for all cases were added, and the calculated conservation of allogeneic packed red blood cells totaled 359.6 units, worth $30,026.60 or $428.95 per case. The break-even point is approximately 12.6 units, and most patient do not receive this volume of salvaged blood. In fact, cell salvage reached cost equivalence in only three cases (4.8%). Moreover, the cost deficit of autologous transfusion during this 2-year period averaged $586.56 per case.

Blood Transfusion, Autologous↗
PubMed1997

Infectious complications after OKT3 induction in liver transplantation.

The present study examines the incidence, risk factors, bacteriology, and mortality of infectious episodes and the role of antimicrobial prophylactic regimens after OKT3 induction in liver transplantation. Infections occurring in the first 6 months were evaluated according to the Centers for Disease Control criteria in 102 transplant recipients. Patients were administered OKT3 for 5 to 10 days, beginning intraoperatively, azathioprine, low-dose prednisone, and delayed introduction of cyclosporine. There were 140 major and 30 minor infections for an incidence of 1.7 infections per patient. Twenty-seven patients (26%) had no infectious episodes during the 6 months of follow-up. Bacterial and fungal infections peaked during the first month posttransplantation, whereas viral infections peaked during the second month. Infection-related mortality was 10%. One-year survival rate of patients who suffered a major infection was less than those who were infection free, but the difference was not statistically significant (79% vs. 89%; P = .61). There was a significantly higher incidence of enterococcal infections under cefotetan prophylaxis than under ampicillin-sulbactam (.375 vs. 11 infections per patient; P = .0017). There were 14 episodes of cytomegalovirus disease (14%) but no cytomegalovirus-related mortality or graft loss, and all cases responded to ganciclovir treatment. Bivariate and multivariate analyses identified only retransplantation as a risk factor for infection. In conclusion, OKT3 induction after liver transplantation is associated with a manageable incidence of bacterial, viral, or fungal infections. This is caused by, at least in part, improved anti-infective prophylaxis.

Adult↗
PubMed1997

Liver transplantation in Ohio.

BACKGROUND: Since its inception in 1984, the Ohio Solid Organ Transplantation Consortium has tracked liver transplantation outcomes for its five member institutions. Presented herein is a 12-year summary of this data analyzed to determine whether, with increasing experience, outcomes have improved in a cost-effective manner. METHODS: Between July 1984 and June 1996, 1,063 liver transplants were performed in Ohio in 943 patients (772 adults and 171 children), of which 943 were primary and 120 were retransplants (13%). Outcome comparisons were made for three eras: 1984-1988, 1988-1992, and 1992-1996. RESULTS: The percentage of urgent (United Network for Organ Sharing status 1 and 2) transplants has decreased (62% to 41%), whereas that of homebound patients has increased (38% to 59%). Average time on the waiting list has increased from 39 to 165 days, and the average length of stay has decreased from 44 to 27 days. Patient survival at 1-year increased in each era (64%, 80%, and 82%, respectively). Although actual hospital charges have remained relatively constant, they have decreased substantially when compared in 1985 dollars as corrected for inflation. CONCLUSIONS: Patients undergoing liver transplantation in Ohio are now listed earlier in the course of their disease and wait longer for their transplant, but enjoy a better chance of survival, have a shorter hospital stay, and a relatively less expensive operation. These data indicate that with increased experience, the Ohio Solid Organ Transplantation Consortium liver transplantation teams perform liver transplantation in a more cost-effective manner.

Adolescent↗
PubMed1996

Late hepatic artery thrombosis in liver allograft recipients is associated with intrahepatic biliary necrosis.

Hepatic artery thrombosis (HAT) after liver transplantation is a potentially life-threatening complication that occurs in 2-25% of patients, depending on several risk factors and the patient population studied. Arterial thrombosis occurring early after liver transplantation is associated with acute fulminant hepatic failure, biliary tract necrosis and leaks, or relapsing bacteremia and is associated with a high rate of graft loss and patient mortality. The onset of late posttransplant HAT (after 6 months) has been thought to have a more benign and often asymptomatic course. The reasons for the differences between the manifestations of early and late HAT are not well understood. We reviewed the adult liver transplant experience at the University of Cincinnati and found four patients with late HAT, three of whom developed severe intrahepatic biliary necrosis. Two patients were successfully retransplanted and 1 patient who refused retransplantation died. One patient had mild, transient graft damage due to gradual arterial stenosis and the development of arterial collaterals prior to thrombosis. Late HAT has a significant potential for irreversible graft damage requiring retransplantation. Screening for the development of hepatic artery stenosis prior to late thrombosis may be worthwhile.

Adult↗
PubMed1996

Increased expression of proliferating cell nuclear antigen in liver allograft rejection.

Detection of proliferating cell nuclear antigen is useful for the study of proliferative activity of neoplastic and non-neoplastic lymphoid, parenchymal, and mesenchymal cells. Allograft rejection is associated with the recruitment of circulating cells and their proliferation in the graft. The intrahepatic expression of proliferating cell nuclear antigen on paraffin-embedded liver biopsy specimens (n = 110 from 32 patients) was examined by an avidin-biotin peroxidase method using a monoclonal antibody to proliferating cell nuclear antigen. The percentage of positive nuclei was determined in hepatocytes, biliary epithelium, and lymphocytes. There were four histologic groups: 1, moderate-to-severe rejection (n = 19); 2, mild rejection (n = 28); 3, nonspecific inflammation (n = 45); and 4, donor livers (n = 18). The percentage of positive nuclei was higher in group 1 compared to group 2 (hepatocytes p = 0.01; biliary epithelium p = 0.0007; lymphocytes p = 0.0001), to group 3 (hepatocytes p = 0.0002; biliary epithelium p = 0.0001; lymphocytes p = 0.0001), and to group 4 (for all three locations p < 0.0001). When group 2 was compared to group 3 the results were significant for biliary epithelium (p = 0.0001) and lymphocytes (p = 0.0001), but not for hepatocytes (p = 0.07). We conclude that proliferating cell nuclear antigen expression, especially in lymphocytes, correlates with the severity of histologic rejection. Proliferating cell nuclear antigen expression may be useful in predicting the progression and response to different antirejection therapies.

Analysis of Variance↗
PubMed1996

A percutaneous technique for venovenous bypass in orthotopic cadaver liver transplantation and comparison with the open technique.

Venovenous bypass minimizes the hemodynamic alterations during the anhepatic phase of liver transplantation. A new technique for the percutaneous placement of the bypass cannulae is described and compared to the cut-down ("open") technique. The records of 81 patients who underwent 94 liver transplants between August 1991 and April 1994 were reviewed for indications for transplant, United Network for Organ Sharing status, mean age, body surface area, bypass technique and time, flow rates, cardiac output, mean arterial pressure and central venous pressure during bypass, the development of deep venous thrombophlebitis, and lymphoceles. Femoral flow rates were higher in the open group (2054 +/- 74 mL/min), compared with the percutaneous group (1726 +/- 74 mL/min) (p = 0.003). Total flow rates in the open (2238 +/- 58 mL/min) and percutaneous (2197 +/- 67 mL/min) groups were not different. Maximum cardiac outputs (L/ min) were higher in the open (10.1 +/- 0.6) versus percutaneous group (7.0 +/- 0.5) (p < 0.0002). Similarly, minimum cardiac outputs (L/min) were higher in the open (8.9 +/- 0.7) versus percutaneous group (5.8 +/- 0.5) (p = 0.003). Other hemodynamic parameters (mean arterial pressure, central venous pressure) were not different between groups. Venous thrombosis occurred in 1/50 (2.0%) and 4/34 (11.8%) patients in the open and percutaneous groups, respectively (p = 0.153). Nineteen lymphoceles occurred in 102 (18.6%) at-risk sites in the open group, whereas no lymphoceles occurred in 66 at-risk sites in the percutaneous group (p < 0.001). Groin lymphoceles occurred in 7/50 (14%) and 0/34 at-risk sites in the open and percutaneous groups, respectively (p = 0.039). Axillary lymphoceles occurred in 12/52 (23.1%) and 0/32 at-risk sites in the open and percutaneous groups, respectively (p = 0.0031). Operative repair of a lymphocele was required in 11/16 (69%) patients. The percutaneous placement of catheters for venovenous bypass has the advantage of comparable flow rates with satisfactory hemodynamics without the lymphatic complications of the cut-down technique.

Adolescent↗