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S J Knechtle

Publications and source records attributed to S J Knechtle.

At least 145 records · Page 8Linked to original sources
PubMed1991

The predictive value of donor liver biopsies for the development of primary nonfunction after orthotopic liver transplantation.

Methods of accurately assessing the suitability of donor livers prior to transplantation are required if the incidence of primary nonfunction (PNF) is to be reduced. This study evaluated the ability of donor liver biopsies to predict the development of primary nonfunction after transplantation. From June 1987 until May 1990, 170 liver transplants were performed in 147 patients. A total of 124 donor liver biopsies were obtained and divided into three groups. Group 1 biopsies (n = 77) were obtained after revascularization of the liver, group 2 biopsies (n = 19) were obtained prior to donor hepatectomy but examined only after implantation, and group 3 biopsies (n = 28) were obtained as in group 2, but were examined prior to implantation. Three of 89 (3.4%) livers interpreted as having normal histology developed primary nonfunction, while one of 26 (3.8%) biopsies interpreted as having a minimal or moderate amount of fatty infiltration developed primary nonfunction. PNF occurred in 7 of 8 livers with severe fatty infiltration (3), hydropic degeneration (3), and centrilobular necrosis (1). A fourth liver with hydropic degeneration and poor function ultimately failed requiring retransplantation 8 weeks later. Analysis of liver function revealed progressive elevation in aspartate-aminotransferase, alanine-aminotransferase, lactate dehydrogenase, and serum ammonia (NH3) with increasing degrees of fatty infiltration. Donor age and weight was also found to be significantly higher in livers with fatty infiltration. This study suggests that donor liver biopsies demonstrating normal histology or minimal-to-moderate fatty infiltration function adequately, but that donor livers with severe fatty infiltration or hydropic degeneration function poorly and should not be transplanted.

Biopsy↗
PubMed1991

Multivariate analysis of donor-specific versus random transfusion protocols in haploidentical living-related transplants.

A total of 127 haploidentical living-related transplants have been performed at our institution since March 1986. A donor-specific transfusion plus azathioprine protocol was used until July 1988 (n = 74) and a random transfusion (RT) protocol without AZA used thereafter (n = 53) in an effort to decrease risk of recipient sensitization and reduce the burden on the prospective donor. All patients were given cyclosporine 8 mg/kg/day orally beginning 1 week prior to transplantation. Immunosuppression was similar in both groups and consisted of triple induction therapy with prednisone, CsA, and AZA. A positive T cell crossmatch eliminated the potential donor. Seven individuals (9.6%) were sensitized in the DST group and 1 (1.9%) in the RT group, leaving 67 and 52 patients in the two groups of the study, respectively. Groups were similar with respect to age, sex, history of pregnancy in female patients, peak and baseline panel-reactive antibody (PRA), DR match, and prior transplants. The groups differed slightly with respect to AB antigens shared, with an advantage in the RT group. Actuarial graft survival was not statistically significantly different between the two groups, with 2-year graft survival of 95% in the DST and 91% in the RT group (log rank, P = 0.16). Patients in the RT group had significantly more rejection episodes and had them sooner than their counterparts in the DST group. At the end of 1 year, 50% of patients in the DST group had at least 1 rejection episode, compared with 75% of patients in the RT group (P = 0.0008). Multivariate (Poisson) analysis of 10 variables was performed, with an overall model P-value of 0.0001. Only DST (P = 0.0001) and pregnancy (P = 0.015) were significant predictors of rejection episodes, both protective. The difference in rejection episodes and the timing with which they occur has not yet translated into a significant difference in graft survival between DST and RT groups.

Adult↗
PubMed1991

Orthotopic liver transplantation in patients 60 years of age and older.

Cyclosporine appears to have abrogated age as a contraindication to kidney transplantation in the elderly, although it is unclear whether this is true for other types of solid organ transplantation. We performed a retrospective analysis of liver transplant recipients who were 60 years of age and older (n = 23) versus recipients of primary transplants who were 18 to 59 years of age (n = 84). Indications in recipients over 60 included alcoholism (6), postnecrotic cirrhosis (6), cancer (4), primary biliary cirrhosis (3), sclerosing cholangitis (2), and one patient with polycystic liver disease. There were no important differences in the initial transplant hospitalization or the incidence of infection and rejection between the two groups. No patient in the over-60 population required retransplantation. Actuarial patient survival is 83% at 2 years for recipients 60 years of age and above compared to 76% patient survival in adult recipients who are under the age of 60. Liver transplant recipients over the age of 60 years have excellent patient and graft survival and the same postoperative morbidity as recipients who are under 60 years of age. Therefore, advanced age does not appear to be a contraindication to orthotopic liver transplantation.

Aged↗
PubMed1990

Anomalous biliary ducts associated with duodenal atresia.

Duodenal atresia is rarely associated with anomalous biliary ducts that permit communication between the proximal and distal duodenal segments. Two such cases are presented herein and the literature is reviewed. Although the typical radiographic pattern of duodenal atresia is the "double bubble" sign with absence of distal bowel gas, air may be present in the distal bowel when anomalous bile ducts provide a conduit around the atretic segment. Contrast studies are generally not performed in the typical clinical and radiographic evaluation of duodenal atresia; however, an upper gastrointestinal series may be useful in defining the more complex anomaly. Clinical presentation may occur relatively late if the biliary communication is large enough to permit passage of some milk or formula. Care should be taken at surgery to avoid obstruction or injury to the anomalous bile ducts, and operative cholangiography may be useful to document continued bile duct patency following repair of the atresia. Theories of the etiology of this anomaly relate to interference with recanalization of the duodenum by the process of hepaticopancreatic duct formation and persistence of the primitive "dual duct" stage.

Bile Ducts↗
PubMed1990

Irradiation for xenogeneic transplantation.

Xenogeneic transplantation (XT) is the transplantation of organs or tissues from a member of one species to a member of another. Mammalian species frequently have circulating antibody which is directed against the foreign organ irrespective of known prior antigen exposure. This antibody may lead to hyperacute rejection. There is no reliable means to avert hyperacute rejection once it ensues so efforts must be directed towards eliminating the pre-existing antibody. In those species in which hyperacute rejection of xenografts does not occur, cell-mediated rejection, similar to allograft rejection, may occur. It is in the prevention of this latter form of rejection that radiation is most likely to be beneficial in XT. Both total lymphoid irradiation (TLI) and selective lymphoid irradiation (SLI) have been investigated for use in conjunction with XT. TLI has contributed to the prolongation of pancreatic islet-cell xenografts from hamsters to rats. TLI has also markedly prolonged the survival of cardiac transplants from hamsters to rats. A more modest prolongation of graft survival has been seen with the use of TLI in rabbit-to-rat exchanges. Therapy with TLI, cyclosporine, and splenectomy has markedly prolonged the survival of liver transplants from hamsters to rats, and preliminary data suggest that TLI may contribute to the prolongation of graft survival in the transplantation of hearts from monkeys to baboons. SLI appears to have prolonged graft survival, when used in conjunction with anti-lymphocyte globulin, in hamster-to-rat cardiac graft exchanges. The current state of knowledge of the use of irradiation in experimental XT is reviewed.

Animals↗
PubMed1990

Pneumatosis intestinalis. Surgical management and clinical outcome.

Pneumatosis intestinalis (PI) occurs in a wide variety of patients, some of whom require urgent surgery, while others can be observed with resolution of symptoms and radiographic findings. During 1 year, 27 patients with PI were prospectively evaluated for clinical, laboratory, and radiographic features that would be useful in predicting the need for surgery, the pathologic findings, and patient outcome. Sixteen of the twenty-seven patients underwent laparotomy, with only one negative exploration. Of the 11 patients not explored, there were two deaths in moribund patients. Seven of nine patients with jejunostomy tubes, recent gastrointestinal anastomoses, inflammatory bowel disease, lactulose therapy, or chemotherapy who did not have clinical evidence of an acute surgical abdomen or metabolic acidosis survived without surgery (two deaths unrelated to the gastrointestinal tract). Patients presenting with bowel obstruction and PI required surgery in seven of nine cases, did not have necrotic bowel, and had 11% mortality. Eight patients with ischemic bowel had a 75% mortality rate, despite surgery. Patients with PI and clinical evidence of bowel obstruction or ischemia usually require urgent surgery, while asymptomatic patients without metabolic acidosis can be safely observed.

Female↗