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A C Farney

Publications and source records attributed to A C Farney.

At least 19 recordsLinked to original sources
PubMed2001

Superiority of portal venous drainage over systemic venous drainage in pancreas transplantation: a retrospective study.

OBJECTIVE: To compare portal and systemic venous drainage of pancreas transplants and demonstrate an immunologic and survival superiority of portal venous drainage. SUMMARY BACKGROUND DATA: Traditionally, solitary pancreas transplants have been performed using systemic venous and bladder drainage, but more recently, the advantages of enteric drainage have been well documented. Although physiologic benefits for portal venous drainage have been described, the impact of portal venous drainage, especially with solitary pancreas transplants, has yet to be determined. METHODS: Since August 1995, 280 pancreas transplants with enteric duct drainage were analyzed. One hundred and seventeen were simultaneous pancreas and kidney (SPK), 63 with systemic venous drainage (SV) and 54 with portal venous drainage (PV). The remainder were solitary transplants; 97 pancreas after kidney (PAK; 42 SV and 55 PV) and 66 transplants alone (PTA; 26 SV and 40 PV). Immunosuppressive therapy was equivalent for both groups. RESULTS: The groups were similar with respect to recipient characteristics and HLA matching. Thirty-six month graft survival for all transplants was 79% for PV and 65% for SV (P =.008). By category, SPK graft survival was 74% for PV and 76% for SV, PAK graft survival was 70% for PV and 56% for SV, and PTA graft survival was 84% for PV and 50% for SV. The rate of at least one rejection episode was also significantly higher in the SV group. At 36 months, for all pancreas transplants, the rejection rate was 21% for PV and 52% for SV (P <.0001). For SPK, rejection rates were 9% for PV and 45% for SV. For PAK, rejection rates were 16% for PV and 65% for SV, and for PTA 36% for PV and 51% for SV. The rejection rates for kidneys following SPK were also lower in the PV group (26% versus 43% for SV). Furthermore, the grades of rejection were milder in PV for all transplants (P =.017). By multivariate analysis, portal venous drainage was the only parameter that significantly affected rejection. CONCLUSION: Graft survival and rejection is superior for PV. These clinical findings are consistent with published reports of experimentally induced portal tolerance and strongly argue that PV drainage should be the procedure of choice for pancreas transplantation.

Adult↗
PubMed2001

Recurrent autoimmunity accelerates destruction of minor and major histoincompatible islet grafts in nonobese diabetic (NOD) mice.

Recurrent autoimmunity destroys nonobese diabetic (NOD) islet isografts, but whether recurrent autoimmunity contributes to islet graft destruction in immunocompetent allogeneic recipients is unknown. In the NOD, a single dose of streptozocin prevents or delays primary autoimmunity, allowing the detection of alloimmunity alone in chemically diabetic hosts (streptozocin-NOD) to be compared to the combined effects of autoimmunity and alloimmunity in spontaneously diabetic NODs (autoimmune-NOD). Islets were isolated from prediabetic NOD (H-2KdDb), nonobese resistant (NOR) (H-2KdDb), Balb/cByJ (H-2d) and B10.BR (H-2k) donors and transplanted to either the renal subcapsule or the intraportal site in autoimmune-NODs or streptozocin-NODs. MHC-matched NOR islets had in definite graft survival in streptozocin-NODs. However, NOR islets showed graft loss at 12.6 +/- 3.2 days in renal subcapsule and at 6.8 +/- 0.1 days in intraportal site of autoimmune-NODs. Partially MHC-matched Balb/cByJ islet grafts failed significantly sooner in autoimmune-NODs than in streptozocin-NODs (p < 0.005). Fully MHC-mismatched B10.BR islet grafts also failed sooner in autoimmune-NODs, but the difference did not reach significance (p < 0.06). Although the streptozocin-NOD was functionally tolerant of MHC-matched NOR islets, NOR islets transplanted into autoimmune-NODs failed sooner than NOD islets in both renal subcapsule (12.6 +/- 3.2 days vs. 26.4 +/- 10.5 days, p = 0.009) and intraportal sites (6.8 +/- 0.1 days vs. 11.5 +/- 1.7 days, p = 0.014). In the autoimmune-NODs, the intraportal site consistently showed shorter graft survival than the renal subcapsule site (NOD: p = 0.009, NOR: p = 0.014, Balb/cByJ: p = 0.008, B10.BR: p = 0.032). In conclusion, autoimmune processes facilitate the alloimmune response to minor and major histocompatibility antigens and accelerate graft destruction. The same autoimmune processes are more pronounced in the intraportal site.

Animals↗
PubMed2000

Simultaneous cadaver pancreas living-donor kidney transplantation: a new approach for the type 1 diabetic uremic patient.

OBJECTIVE: To review the authors' experience with a new approach for type I diabetic uremic patients: simultaneous cadaver-donor pancreas and living-donor kidney transplant (SPLK). SUMMARY BACKGROUND DATA: Simultaneous cadaver kidney and pancreas transplantation (SPK) and living-donor kidney transplantation alone followed by a solitary cadaver-donor pancreas transplant (PAK) have been the transplant options for type I diabetic uremic patients. SPK pancreas graft survival has historically exceeded that of solitary pancreas transplantation. Recent improvement in solitary pancreas transplant survival rates has narrowed the advantage seen with SPK. PAK, however, requires sequential transplant operations. In contrast to PAK and SPK, SPLK is a single operation that offers the potential benefits of living kidney donation: shorter waiting time, expansion of the organ donor pool, and improved short-term and long-term renal graft function. METHODS: Between May 1998 and September 1999, the authors performed 30 SPLK procedures, coordinating the cadaver pancreas transplant with simultaneous transplantation of a laparoscopically removed living-donor kidney. Of the 30 SPLKs, 28 (93%) were portally and enterically drained. During the same period, the authors also performed 19 primary SPK and 17 primary PAK transplants. RESULTS: One-year pancreas, kidney, and patient survival rates were 88%, 95%, and 95% for SPLK recipients. One-year pancreas graft survival rates in SPK and PAK recipients were 84% and 71%. Of 30 SPLK transplants, 29 (97%) had immediate renal graft function, whereas 79% of SPK kidneys had immediate function. Reoperative rates, early readmission to the hospital, and initial length of stay were similar between SPLK and SPK recipients. SPLK recipients had a shorter wait time for transplantation. CONCLUSIONS: Early pancreas, kidney, and patient survival rates after SPLK are similar to those for SPK. Waiting time was significantly shortened. SPLK recipients had lower rates of delayed renal graft function than SPK recipients. Combining cadaver pancreas transplantation with living-donor kidney transplantation does not harm renal graft outcome. Given the advantages of living-donor kidney transplant, SPLK should be considered for all uremic type I diabetic patients with living donors.

Adult↗
PubMed2000

Simultaneous pancreas-kidney (SPK) and pancreas living-donor kidney (SPLK) transplantation at the University of Maryland.

The evolution of enteric and portal venous drainage, better immunosuppression, and better patient care has elevated pancreas transplantation with dramatically improved results. At our center, long-term graft survival and rejection has significantly improved with portal venous drainage, which has become our gold standard. This improvement is exemplified by the excellent one-year patient and graft survival rates for SPLK transplants. SPLK has proven to be an ideal approach in uremic Type 1 diabetic patients with living donors and should become the procedure of choice for that population. Moreover, the improved monitoring of rejection has allowed a similar success of pancreas transplantation alone in non-uremic patients with brittle diabetes. The treatment of diabetes mellitus has room for great improvement, however, and there is no question that islet transplantation, xenotransplantation, and the pursuit of immunologic tolerance will play an extremely important role in that endeavor.

Academic Medical Centers↗
PubMed1999

Laparoscopic versus open donor nephrectomy: comparing ureteral complications in the recipients and improving the laparoscopic technique.

BACKGROUND: Laparoscopic live donor nephrectomy (LDN) is a recently developed procedure, the performance of which needs to be studied. Given the reported advantages in the donors, this study looks at graft outcome and ureteral complications in recipients of kidneys procured by open donor nephrectomy (ODN) versus LDN. METHODS: The LDN recipients consisted of 193 patients since 3/27/96. A total of 168 ODN recipients from 1991 to 1998 served as controls. Immunosuppression protocols were similar for both groups. RESULTS: Two-year graft survival for LDN and ODN was 98% and 96%, respectively. Two-year patient survival for LDN and ODN was 98% and 97%, respectively. The incidence of delayed graft function and mean serum creatinine at 3 and 12 months was similar in both groups. However, the number of ureteral complications that required operative repair was significantly higher for LDN recipients compared to ODN recipients, 7.7% (n=15) vs. 0.6% (n=1) respectively (P=0.03). Ureteral stenting was required in an additional 3.1% (n=6) of LDN and 2.4% (n=4) of ODN (P=NS). There was, however, a learning curve with time. For the first 130 LDN patients, a total of 20 ureteral complications were recorded, whereas only one occurred in the more recent 63 patients (P=0.03). CONCLUSIONS: The higher ureteral complication rate in LDN recipients has improved over time as technical causes have been identified. We have noted significant improvement in ureteral viability by using the endogastrointestinal anastomosis instrument on the ureter and peri-ureteral tissue. LDN is therefore an excellent alternative to ODN. Identification of hazards unique to this technique is critical before its broader application.

Adult↗
PubMed1998

The shrinking renal replacement therapy "break-even" point.

BACKGROUND: This study examines the current cost of live donor (LD) transplantation at our institution, and compares it with that of dialysis. METHODS: The study population consisted of 184 consecutive adult recipients of laparoscopically procured LD kidney transplants. Cost-containment measures instituted during this series included elimination of routine postoperative antilymphocyte induction and an accelerated discharge clinical pathway with planned discharge of the recipient on postoperative day (POD) 2. Costs of the transplants to Medicare were estimated from hospital charges, readmission rates, and immunosuppressant usage. These were compared with published costs of dialysis to Medicare in terms of a fiscal transplant-dialysis break-even point. RESULTS: Kaplan-Meier patient and graft survival rates at 1 year were 97 and 93%, respectively. Among patients followed for at least 90 days and treated with no induction and either cyclosporine-mycophenolate mofetil or tacrolimus-mycophenolate mofetil, acute rejection rates were low (27.6 and 13.9%, respectively). In the last 124 patients, 32.3% were discharged by POD 3 and 71.8% by POD 6, with corresponding mean transplant hospital charges (excluding organ acquisition) of $11,873 and $17,350, respectively. The 30-day readmission rate for patients discharged on the accelerated pathway by POD 3 was only 16%. The least expensive subgroup in the present study (30% of patients) was that of patients discharged by POD 6 and not readmitted during the first year; the break-even point with dialysis costs was calculated as 1.7 years after the transplant. CONCLUSIONS: The cost of LD transplants can be safely reduced by elimination of routine postoperative anti-lymphocyte immune induction and by an early discharge clinical pathway. Uncomplicated LD kidney transplants, meaning those with a short length of stay in the hospital after transplantation and no need for readmission within the first year, accrue savings over dialysis within 2 years.

Adolescent↗
PubMed1998

Donor iliac vein interposition during liver transplantation in a patient with a migrated transjugular intrahepatic portosystemic shunt.

BACKGROUND: Transjugular intrahepatic portosystemic shunts (TIPS) are sometimes used to reduce the risk of variceal bleeding or treat intractable ascites before orthotopic liver transplantation (OLT). TIPS usually do not make OLT more difficult, but rarely, malposition of TIPS can significantly complicate OLT. METHOD AND RESULTS: The following report describes a patient in whom an initially well-placed Wallstent migrated to the confluence of the splenic and superior mesenteric veins. During liver transplantation, the portal vein containing the Wallstent was completely resected, and the portal vein was reconstructed with donor iliac vein. After sewing the iliac vein onto the portal remnant, the liver transplant was completed under portosystemic bypass. The patient had an uneventful recovery. CONCLUSIONS: Wallstents can migrate within the portal vein. An interposition graft of donor vein allows full resection of the portal vein containing a migrated stent and facilitates portosystemic bypass and portal anastomosis.

Foreign-Body Migration↗
PubMed1998

Mycophenolate mofetil reduces the risk of acute rejection less in African-American than in Caucasian kidney recipients.

BACKGROUND: Multicenter clinical trials have shown that mycophenolate mofetil (MMF) reduces the risk of acute rejection, but it is unknown whether African-Americans constitute a subgroup of recipients less likely to benefit from MMF. METHODS: This study compared the acute rejection rates within 6 months of kidney transplantation in MMF-treated transplant patients with those on azathioprine (AZA) at a single center. The study population consisted of 353 consecutive recipients of cadaver or living donor kidney transplants. African-Americans constituted 43% of the patients on AZA and 49% of the patients on MMF. Variables used in a Cox regression analysis included MMF immunosuppression, recipient race, type of transplant, delayed graft function, postoperative immune induction, average cyclosporine trough level, and HLA mismatch. RESULTS: Significantly fewer patients on MMF experienced a biopsy-proven rejection episode than those treated with AZA (24% vs. 42%, respectively; relative risk [RR]=0.57, P=0.001). This decrease in risk was greater in Caucasian transplant recipients (MMF vs. AZA: 16% vs. 46%, RR=0.35, P < 0.001) than in African-American patients (32% vs. 36%, RR=0.88, P=0.6). Within each race stratum, the mean cyclosporine trough levels averaged over 2-week intervals were nearly identical for AZA- compared with MMF-treated patients. In the regression model, the effect of MMF on the incidence of rejection was again less in African-American than in Caucasian patients. CONCLUSIONS: Kidney recipients treated with MMF have a significantly lower risk of acute rejection within 6 months of transplantation than those given AZA. This reduction in risk is significantly less in African-American recipients than Caucasians.

Adult↗
PubMed1998

Kidney transplantation at the University of Maryland.

1. The number of kidney transplants performed at the University of Maryland increased yearly from 51 in 1991 to 285 in 1998. Over the past 3 years, the increase in the number of kidney transplants can be ascribed almost exclusively to a marked increase in living donor transplants, from 49 cases in 1995 to 130 cases in 1998; a 160% increase. The increase in our frequency of living-donor kidney transplantation can be attributed to a formal family education program and the availability of the laparoscopic technique for kidney removal. 2. In addition to the availability of the laparoscopic technique, a number of special programs has allowed an increased number of living donor kidney transplants. This includes a special protocol for transplantation of Epstein-Barr virus negative recipients, a protocol for transplantation of patients who have a positive crossmatch with a living donor, as well as, the simultaneous living donor kidney/cadaver pancreas "SPK(LRD/PTA)" program. 3. The one-year graft and patient survival for the entire program was 87.0% and 94.5%, respectively. However, the more recent graft survival rates have markedly increased; Since August 1995, the one-year graft and patient survival was 89.8% and 95.8%, respectively. 4. Improvement in immunosuppression has lead to dramatic improvement in the success rates in living-donor kidney transplants. Despite the omission of antibody-based induction therapy, the one-year graft survival rate using a mycophenolate mofetil/tacrolimus-based immunosuppression protocol was 96.4%. The one-year rejection rate was 8% in Caucasian patients and 14% in African-American patients in this subgroup of living-donor kidney transplant recipients. 5. The data demonstrate that the use of the living-donor transplant option is grossly underutilized. Estimates are presented that more than 11,000 living-donor kidney transplants should be possible in the US yearly.

Black People↗
PubMed1996

Islet Autotransplantation after total pancreatectomy in a child.

Islet autotransplantation can prevent surgically induced diabetes after total pancreatectomy in adults; however, the efficacy of this procedure has not been established in children. The authors report the case of a 12-year-old boy who underwent total pancreatectomy and islet autotransplantation for intractable pain caused by idiopathic chronic pancreatitis. Islets were prepared from the excised pancreas by collagenase digestion and mechanical dispersion. The resultant preparation, containing 109,500 islets, was injected into the recipient's liver via the portal vein. No complication from the pancreatectomy or transplant occurred. Postoperatively, the patient had complete relief of abdominal pain. He remained insulin-independent, with normal fasting blood glucose and hemoglobin A1c levels, for 21/2 years. Preoperatively, the acute insulin response and the rate of glucose disappearance (Kg) were 213 microU/mL and 2.14% (respectively) after intravenous administration of 20 g of glucose. Although lower than pretransplantation values, both insulin response and Kg remained normal at 4 months (88 microU/mL; Kg, 1.01%); however, these decreased further, to below normal, by 2 years posttransplantation (10 microU/mL; Kg, 0.67%). Two-and-a-half years after transplantation, fasting hyperglycemia (> 200 mg/dL) was evident, and the patient was begun on exogenous insulin. Five years posttransplantation he remains insulin-dependent with a fasting serum C-peptide level of 0.20 ng/mL, which increased to 0.35 ng/mL in response to intravenous arginine, indicating sustained islet function. During the documented decreases in insulin secretion and Kg posttransplantation, the patient's body weight increased by 65% (from 34 to 56 kg) as a result of normal growth; the number of transplanted islets relative to body mass decreased accordingly, from 3,200 to 1,950 islets per kilogram of body weight. In this case, the number of islets transplanted likely could not meet the increased insulin demands of the larger body mass. Thus, exogenous insulin supplementation was needed to prevent hyperglycemia. In conclusion, insulin independence was initially established in a child by islet autotransplantation after total pancreatectomy. The failure of the islets to maintain normoglycemia long-term suggests that a sufficient number must be transplanted (to meet the demands of normal growth and development) for sustained insulin independence.

Blood Glucose↗
PubMed1996

Does re-exposure to mismatched HLA antigens decrease renal re-transplant allograft survival?

UNLABELLED: We analyzed 420 kidney retransplants at the University of Minnesota, 87 of which did and 333 which did not share HLA mismatches with the previous transplant. There was no difference in outcome. We conclude that exceptions to routine HLA matching policies do not have to be made for kidney retransplants. OBJECTIVE: To determine if the kidney graft functional survival rate for retransplants is influenced by presence of HLA mismatches in common with the previous (failed) transplant. SUMMARY BACKGROUND DATA: Kidney retransplants have a lower function rate than primary grafts. An anamnestic response to HLA antigens shared with the previous donor could be one factor responsible, but reports in the literature are conflicting. METHODS: Of 420 kidney retransplants with HLA information done at the University of Minnesota, 87 shared > or = 1 HLA antigens specifically mismatched with the previous donor (63 cadaver and 24 living donor retransplants), while 333 did not (247 cadaver, 86 living donor). Patient and graft survival rates were calculated by life-table analysis for recipients with vs. without repeat mismatches, with the significance of differences determined by the Lee-Desu statistic. RESULTS: Patient and kidney graft retransplant survival rate curves were not significantly different (p > or = 0.41) for those exposed or not exposed to the same HLA mismatches as before. At 2 years, 70% vs. 61%, respectively, of cadaver grafts and 71% vs. 78%, respectively, of living donor grafts were functioning. CONCLUSIONS: The probability of a successful outcome with a kidney retransplant is no different for patients who do than for those who do not receive an organ sharing HLA mismatches with the previous donor. Exceptions to routine HLA matching policies do not need to be made for kidney retransplants.

Cadaver↗
PubMed1995

Autologous islet transplantation to prevent diabetes after pancreatic resection.

BACKGROUND: Extensive pancreatic resection for small-duct chronic pancreatitis is often required for pain relief, but the risk of diabetes is a major deterrent. OBJECTIVE: Incidence of pain relief, prevention of diabetes, and identification of factors predictive of success were the goals in this series of 48 patients who underwent pancreatectomy and islet autotransplantation for chronic pancreatitis. PATIENTS AND METHODS: Of the 48 patients, 43 underwent total or near-total (> 95%) pancreatectomy and 5 underwent partial pancreatectomy. The resected pancreas was dispersed by either old (n = 26) or new (n = 22) methods of collagenase digestion. Islets were injected into the portal vein of 46 of the 48 patients and under the kidney capsule in the remaining 2. Postoperative morbidity, mortality, pain relief, and need for exogenous insulin were determined, and actuarial probability of postoperative insulin independence was calculated based on several variables. RESULTS: One perioperative death occurred. Surgical complications occurred in 12 of the 48 patients (25%): of these, 3 had a total (n = 27); 8, a near-total (n = 16); and 1, a partial pancreatectomy (p = 0.02). Most of the 48 patients had a transient increase in portal venous pressure after islet infusion, but no serious sequelae developed. More than 80% of patients experienced significant pain relief after pancreatectomy. Of the 39 patients who underwent total or near-total pancreatectomy, 20 (51%) were initially insulin independent. Between 2 and 10 years after transplantation, 34% were insulin independent, with no grafts failing after 2 years. The main predictor of insulin independence was the number of islets transplanted (of 14 patients who received > 300,000 islets, 74% were insulin independent at > 2 years after transplantation). In turn, the number of islets recovered correlated with the degree of fibrosis (r = -0.52, p = 0.006) and the dispersion method (p = 0.005). CONCLUSION: Pancreatectomy can relieve intractable pain caused by chronic pancreatitis. Islet autotransplantation is safe and can prevent long-term diabetes in more than 33% of patients and should be an adjunct to any pancreatic resection. A given patient's probability of success can be predicted by the morphologic features of the pancreas.

Adolescent↗
PubMed1994

Effect of 15-deoxyspergualin on immediate function and long-term survival of transplanted islets in murine recipients of a marginal islet mass.

15-Deoxyspergualin (DSG), a macrophage immunomodulatory agent, was used as a probe in a murine model of islet transplantation to examine 1) the significance of the nonspecific, macrophage-mediated effector arm of beta-cell injury in recipients of a marginal mass of isologous islets by analyzing the duration of temporary posttransplant hyperglycemia, a parameter of immediate beta-cell function; and 2) whether long-term (> 100 days) functional survival could be achieved in recipients of a marginal mass of allogeneic islets. A dose-response study of the number of islets required to ameliorate diabetes showed that 150 isologous islets per recipient resulted in a 75% incidence of cure at a mean of 39.2 +/- 5.8 days posttransplant. DSG-treated (0.625 mg.kg-1.day-1 intraperitoneally) recipients of isologous islets demonstrated a significant (P < 0.01) reduction in the duration of temporary posttransplant hyperglycemia (16.8 +/- 3.2 vs. 39.2 +/- 5.8 days), and DSG-treated recipients of allogeneic islets demonstrated a significant (P < 0.03) improvement in the rate of achieving long-term functional survival (75 vs. 22% in untreated control animals). Finally, identical rates of islet engraftment were found among control animals and DSG-treated animals by measurement of tissue insulin content in transplanted specimens. The results are consistent with the hypothesis that DSG alters the duration of temporary posttransplant hyperglycemia and extends long-term functional survival in murine recipients of a marginal mass of islets, not by affecting the efficiency of islet engraftment, but by suppression of the inhibitory effects on beta-cell function by nonspecific, macrophage mediators.

Animals↗