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M D Stegall

Publications and source records attributed to M D Stegall.

At least 37 records · Page 2Linked to original sources
PubMed1996

Evidence of recurrent autoimmunity in human allogeneic islet transplantation.

We transplanted 10,000 isolated, handpicked human pancreatic islets into the subfascial compartment of the forearm muscle of a type I diabetic recipient who had received a successful renal transplant one year prior. The recipient was maintained on his usual immunosuppressive therapy of cyclosporine, azathioprine, and prednisone. A biopsy performed 7 days after transplantation showed normal islets with both insulin- and glucagon-staining cells present and no lymphocytic infiltration. A second biopsy performed 14 days after transplantation showed a dense mononuclear cell infiltrate with a preferential loss of insulin-staining cells relative to glucagon-staining cells in the islets. These data are consistent with recurrent autoimmune diabetes in an isolated islet allograft in an immunosuppressed type I diabetic recipient. In addition, this forearm subfascial site may be a useful means to monitor islet rejection and autoimmune recurrence in therapeutic intraportal islet allografts.

Adult↗
PubMed1996

Autoimmune destruction of islet grafts in the NOD mouse is resistant to 15-deoxyspergualin but sensitive to anti-CD4 antibody.

Islet allografts transplanted into Type I diabetic recipients may be destroyed by allorejection or recurrent autoimmune diabetes. We studied islet transplantation in three murine models in order to determine the relative sensitivity of autoimmunity and alloimmunity to two immunosuppressive agents that may be useful in clinical islet transplantation: 15-deoxyspergualin (DSG) and anti-CD4 antibody (GK 1.5). In the model in which only allorejection occurs (BALB/c islets transplanted into streptozotocin-induced diabetic CBA or streptozotocin-induced diabetic NOD recipients), both DSG and anti-CD4 antibody treatment led to indefinite survival of allogeneic islets (>100 days in both treatments). In the second model in which only recurrent autoimmunity can destroy islet grafts (islets from NOD donors transplanted into spontaneously diabetic NOD recipients), only anti-CD4 treatment caused prolonged graft survival [MST 36.7 +/- 6.8 days vs 9.8 +/- 1.8 days (controls), P < 0.0002]. Treatment with DSG did not cause any increase in graft survival (MST 12.6 +/- 5.4 days, NS). Finally, using a model in which both autoimmunity and allorejection may occur (BALB/c to spontaneously diabetic NOD mice), treatment with anti-CD4 caused marked graft prolongation [42.0 +/- 14.5 days vs 7.2 +/- 0.8 days (control), P < 0.002] while DSG again did not prolong graft survival with respect to untreated recipients (9.8 +/- 3.0, NS). We conclude that recurrent autoimmunity in the NOD mouse involves a CD4+ T cell that is not sensitive to DSG. Anti-CD4 antibody may be useful in human clinical islet transplantation trials because it seems to prevent both allorejection and recurrent autoimmunity.

Animals↗
PubMed1995

Metabolic complications after liver transplantation. Diabetes, hypercholesterolemia, hypertension, and obesity.

We retrospectively studied the incidence of diabetes, hypercholesterolemia, hypertension, and obesity in 123 consecutive adult liver transplant recipients (61 men and 62 women) who were alive at least 1 year after transplantation. We also studied the change in these metabolic complications in 61 patients who subsequently were able to be tapered to 5 mg prednisone per day. One year after transplantation--a point at which almost all patients were on maintenance immunosuppression and had stable graft function--the incidence of diabetes was 13% and hypertension was 69.1%. The overall incidence of hypercholesterolemia (serum cholesterol > 240 ng/ml) was 31% and was more frequent in women than in men (38.7% vs. 23.0%, P < 0.06). The incidence of obesity at 1 year was 41.9% in women and 39.3% in men. With tapering of prednisone from 10 mg to 5 mg per day in 61 patients, the mean serum cholesterol decreased from 224.6 +/- 65.2 mg/dl to 203.3 +/- 65.5 mg/dl, P < 0.005. With steroid tapering, 8 patients were able to discontinue antihypertensive medications and 4 were able to discontinue insulin treatment for diabetes. Five patients became obese during the steroid-tapering period. No patient developed irreversible rejection with steroid tapering and no immunologic graft losses occurred more than a year after transplantation. Nine patients who lived a year subsequently died. Of these, 7 patients were diabetic and 2 died of cardiac disease. We conclude that metabolic complications such as diabetes, hypertension, and hypercholesterolemia are common later after liver transplantation and that these may contribute to patient morbidity and mortality. In addition, we conclude steroid tapering to 5 mg/day does not lead to graft loss and may decrease the incidence and severity of late metabolic complications.

Adult↗
PubMed1995

Prolongation of islet allograft survival with an antibody to vascular cell adhesion molecule 1.

BACKGROUND: The purpose of this study was to determine whether an antibody to vascular cell adhesion molecule 1 (VCAM1) prolongs the survival of neovascularized pancreatic islet allografts. METHODS: We treated CBA (H-2k) recipients of BALB/c (H-2d) islet allografts with anti-VCAM1 antibody (400 micrograms/day for 20 days). Sensitized recipients of islet grafts also were treated with anti-VCAM1. To study mechanism we performed mixed lymphocyte reactions (MLRs) with anti-VCAM1 and studied the graft infiltrate in treated recipients. RESULTS: Anti-VCAM1-treated CBA recipients showed prolonged graft survival with indefinite survival in five of nine cases. Anti-VCAM1 prevented proliferation in an MLR but not when added 36 hours after the beginning of the MLR. Anti-VCAM1 did not prolong allograft survival in sensitized recipients and did not prevent lymphocytic infiltration of the graft at 7 days. CONCLUSIONS: Anti-VCAM1 prolongs allograft survival in neovascularized islets in which the donor vascular endothelium plays little or no role in immunogenicity. VCAM1 appears to be important in the afferent phase (lymphocyte activation) of the allograft response. Once activated, either late in an MLR or in sensitized recipients, lymphocytes are not dependent on VCAM1 for function. Finally, anti-VCAM1 does not appear to affect the homing of lymphocytes to the allograft.

Animals↗
PubMed1994

Clinical experience with human anodal trypsinogen (HAT) for detection of pancreatic allograft rejection.

To date one of the major dilemmas in clinical pancreas transplantation is the lack of a reliable indicator for pancreas rejection. In a consecutive series of 52 patients undergoing simultaneous pancreas and kidney (SPK) transplantation with bladder drainage technique between October 1991 and December 1992 a new test using serial levels of serum human anodal trypsinogen (HAT) was evaluated for its efficacy to detect pancreas rejection. Postoperative baseline levels of HAT were compared to peak HAT values at time of rejection. HAT profiles at time of rejection were calculated and compared to profiles of urinary amylase, serum amylase, fasting blood sugar and serum creatinine. In this series one year patient survival was 97%, graft survival of the pancreas 86% and of the kidney 90%. In 71% of the patients at least one rejection episode occurred. At time of kidney-biopsy proven rejection with a concurrent serum creatinine rise a significant HAT level rise to more than 1000 ng/ml was observed from baseline levels of 200 ng/ml (P < 0.001) indicating kidney and pancreas rejection (73%). Urinary amylase levels decreased in the majority of rejection episodes at the same time from baseline levels to less than 20,000 U/l. In 25% of the rejection episodes a significant serum creatinine rise was observed without a HAT rise or urinary amylase decrease indicating kidney-only rejection, while in 2% a urinary amylase decrease and simultaneous HAT also was observed with a negative kidney biopsy indicating pancreas-only rejection. We feel that increase in HAT levels significantly correlates with pancreas rejection. After SPK, determination of HAT is an additional helpful non-invasive test. In pancreas transplantation alone HAT can be a useful indicator to detect rejection and facilitate timing of a pancreas biopsy and initiation of antirejection treatment.

Adult↗
PubMed1994

Urological complications and enteric conversion after pancreas transplantation with bladder drainage.

In summary, we feel that excellent 5-year patient and graft survival results can be obtained using SPK transplantation with bladder drainage technique. Despite the good results, a significant morbidity with prolonged hospitalization is seen after pancreas transplantation. This increased morbidity is due to infectious complications, rejection and urological complications. As a result of the popularity of bladder drainage, the complications after pancreas transplantation have shifted from intraabdominal to urological. Enteric conversion after SPK transplantation is the treatment of choice for chronic hematuria and a duodenal segment leak. In our hands this method appeared to be a safe and reliable procedure with a low complication rate. Enteric conversion should be considered in early leaks after failure of one attempt to suture repair the anastomotic site. In larger leaks or late leaks, it is advisable to perform an immediate enteric conversion. With the considerations above one might ask why enteric conversion is not our current primary choice for the initial transplant procedure. We have, however, noted a higher incidence of postoperative intraabdominal septic complications as well as mycotic aneurysms at the arterial suture line in a small series of 16 primarily enterically drained pancreas transplants. We also fear that the leakage rate after primary duodenoenteric drainage could be higher because of significant edema after transplantation in the preserved duodenal segment. We doubt, therefore, that the primary anastomosis with the bowel is as safe as one performed during enteric conversion when preservation injury has been resolved. At that point the patient is in stable condition and on significantly lower doses of immunosuppression than at the time of transplantation. This study demonstrates that urological complications constitute a major part of the morbidity after SPK transplantation. Despite this fact, appropriate treatment including enteric conversion can resolve most of the complications and prevent long-term morbidity or even graft loss.

Drainage↗
PubMed1993

Risk factors for primary dysfunction after liver transplantation--a multivariate analysis.

In a retrospective analysis on 323 orthotopic liver transplant procedures performed between July 1984 and October 1991 the incidence of two forms of primary dysfunction (PDF) of the liver: primary nonfunction (PNF), and initial poor function (IPF) were studied. The incidence of PDF was 22% (73/323) with 6% PNF (20/323) and 16% IPF (53/323), while 78% (250/323) had immediate function (IF). Occurrence of both IPF and PNF resulted in a higher graft failure rate (P < 0.001), retransplantation rate (P < 0.001), and patient mortality (P < 0.003) within the first three months after OLTx. Univariate analyses of donor and recipient factors and their influence on PDF demonstrated that longer donor hospitalization (> 3 days), older donor age (> 49 years), extended preservation times (> 18 hr), and fatty changes in the donor liver biopsy, as well as reduced-size livers, younger recipient age, and renal insufficiency prior to OLTx, significantly affected the incidence of IPF and PNF. Multivariate analysis of potential risk factors showed that reduced-size liver (P = 0.0001), fatty changes on donor liver biopsy (P = 0.001), older donor age (P = 0.009), retransplantation (P = 0.01), renal insufficiency (P = 0.02), and prolonged cold ischemia times (P = 0.02) were independently associated with a higher incidence of IPF and PNF. No statistical correlation was found between PDF and etiology of ESLD, nutritional status of the recipient, UNOS status, and Child-Pugh classification in this study. We conclude that PNF and IPF are both separate clinical entities that have a significant effect on outcome after OLTx. Routine donor liver biopsies are recommended to decrease the rate of IPF and PNF. The combination of risk factors shown to be significant for PDF should be avoided--and, if that is not possible, the only variable that can be controlled, the preservation time, should be kept as short as possible.

Adolescent↗
PubMed1993

Retransplantation of the liver--a seven-year experience.

Three hundred and four patients underwent 362 liver transplants between July 1984 and April 1992. Fifty-eight retransplants were performed in 44 patients (14.5%). Thirty-four patients underwent two (77.3%), seven patients three (15.9%), two patients four (4.5%), and one patient five (2.3%) transplants. Poor function accounted for 23 retransplants (6.4%), technical problems for 19 retransplants (5.2%), and rejection for 15 retransplants (4.1%). One-month patient survivals after retransplantation for poor function, technical problems, or rejection were similar (79.0%, 73.4%, and 80.0%, respectively). No difference in retransplantation rates were seen between adults and children receiving whole liver transplants (WLT) (11.6% versus 19.1%). However, retransplantation for poor function was more common in pediatric recipients receiving reduced-size liver transplants (RLT) (20.0% versus 0.0%, P < 0.01), while retransplantation for hepatic artery thrombosis (HAT) was more common in pediatric recipients receiving WLT (16.7% versus 2.8%, P < 0.05). The presence of multiorgan system failure of greater than four was associated with a high mortality (90%), whereas patients undergoing emergent retransplantation who had less than four systems fail had a survival of 73.9% and patients who underwent elective retransplantation had a survival rate of 81.8%. Length of stay and cost of liver transplantation was higher in patients undergoing retransplantation when compared with primary transplants (29.7 +/- 14.9 days versus 58.4 +/- 38.9 days and $122,358 +/- 59,782 versus $289,302 +/- 126,907, P < 0.01). The overall actuarial one-year patient survival in primary transplants was 86.6% and in retransplants 74.8%, and at five years these were 71.4% versus 62.5%, respectively (P < 0.05). Our results support continued retransplantation of the liver unless the patient's medical condition dictates otherwise.

Adolescent↗
PubMed1993

Two hundred consecutive simultaneous pancreas-kidney transplants with bladder drainage.

BACKGROUND: Since 1982, 288 pancreas transplantations have been performed at the University of Wisconsin. This report reviews our experience with 200 consecutive simultaneous pancreas-kidney (SPK) transplantations during a 7-year period. METHODS: Two hundred consecutive SPK transplantations were performed between December 1985 to October 1992. Immediate posttransplant function and surgical and infectious complications were evaluated. Frequency of rejection episodes were analyzed, as was 5-year patient and graft survival. RESULTS: All but four pancreas transplants functioned immediately after transplantation. Three pancreas transplants failed because of thrombosis and one from primary nonfunction. Five-year patient survival was 90.2%, kidney survival 80.3%, and pancreas survival 78.6%. There were 54 surgical complications. Fifteen patients have died since 1985. The most frequent cause of death was infection (three patients). A total of 678 infectious episodes were recorded. Urinary tract infection (n = 344) was the most frequent type of infection. Enteric conversion was necessary in 35 patients, with the most frequent indication being a leak of the duodenal segment. CONCLUSIONS: We concluded from this series that SPK transplantation is associated with higher cost and morbidity as compared with kidney transplantation alone. However, excellent long-term survival in combination with the clearly demonstrated benefits for secondary diabetic complications indicate that SPK transplantation is the procedure of choice for carefully selected patients with diabetes.

Adolescent↗