Thomas R. Weber

Transplantation of infected kidneys: clinical and experimental results.

SUMMARY Clinical experience with transplantation of kidneys infected prior to implantation led to a dog experiment designed to delineate the best mode of therapy. Five groups of dogs were homotransplanted and immunosuppressed. The donor kidneys were perfused for 4 hr. Dogs in group 1 were controls, received no gentamicin, and the perfusate for their transplant was sterile. The animals in group 2 received kidneys perfused with gentamicin-sensitive Escherichia coli-contaminated perfusate and were not protected with gentamicin. Average death in this group was within 4 days, secondary to anastomotic rupture or generalized sepsis. The dogs in group 3 were treated preoperatively and thereafter with gentamicin and received a perfusatecontaminated kidney. They did as well as the controls, with no evidence of sepsis at autopsy 10 days post-transplantation. The animals in group 4 received a perfusate-contaminated kidney but were protected with gentamicin beginning 1 day post-transplantation. Average death was at 6 days; most showed evidence of E. coli sepsis at autopsy. The dogs in group 5 received a kidney, the perfusate of which contained E. coli plus gentamicin. They did as well as the controls. To evaluate the effect of gentamicin in the perfusate, two subgroups of five dogs each were autotransplanted after 4 hr of perfusion with and without gentamicin. Comparison showed no detectable differences in serial serum creatinine levels and in microscopic changes of the transplanted kidneys after 10 days.

Viable vein graft preservation

Homologous vein grafts are becoming increasingly useful in patients without suitable autologous saphenous veins for peripheral arterial bypass procedures [4, 81. However, fresh veins are the only tissue that has been used successfully in homograft vascular reconstruction in terms of long-term patency [4]. The advantages of a reliable method of long-term storage of viable vein segments and the ultimate creation of a vein “bank” are therefore apparent. Dimethylsulfoxide (DMSO) is a low molecular weight compound that diffuses readily across cell membranes [2] and has been shown to be an effective cryoprotectant avoiding cellular dehydration, a major cause of cell death during freezing [2]. The DMSO has been used for successful cryopreservation of other tissues [3, 61, but has not been utilized for vein graft preservation. This study assesses a method for the longterm preservation of viable vein segments by freezing in liquid nitrogen with DMSO cryopreservation.

Intraoperative blood transfusions in highly alloimmunized patients undergoing orthotopic liver transplantation.

Intraoperative blood requirements were analyzed in patients undergoing primary orthotopic liver transplantation and divided into two groups on the basis of panel reactive antibody of pretransplant serum measured by lymphocytotoxicity testing. One group of highly sensitized patients (n = 25) had PRA values of over 70% and the second group of patients (n = 26) had 0% PRA values and were considered nonsensitized. During the transplant procedure, the 70% PRA group received considerably greater quantities of blood products than the 0% PRA group--namely, red blood cells: 21.1 +/- 3.7 vs. 9.8 +/- 0.8 units (P = 0.002), and platelets: 17.7 +/- 3.2 vs. 7.5 +/- 1.5 units (P = 0.003). Similar differences were observed for fresh frozen plasma and cryoprecipitate. Despite the larger infusion of platelets, the blood platelet counts in the 70% PRA group were lower postoperatively than preoperatively. Twenty patients in the 70% PRA group received platelet transfusions, and their mean platelet count dropped from 95,050 +/- 11,537 preoperatively to 67,750 +/- 8,228 postoperatively (P = 0.028). In contrast, nearly identical preoperative (84,058 +/- 17,297) and postoperative (85,647 +/- 12,445) platelet counts were observed in the 17 0% PRA patients who were transfused intraoperatively with platelets. Prothrombin time, activated partial thromboplastin time, and fibrinogen levels showed no significant differences between both groups. These data demonstrate that lymphocytotoxic antibody screening of liver transplant candidates is useful in identifying patients with increased risk of bleeding problems and who will require large quantities of blood during the transplant operation.

Propagation of alloreactive lymphocytes from histologically negative endomyocardial biopsies from heart transplant patients: association with subsequent histological evidence of allograft rejection

Endomyocardial biopsies from heart transplant patients were cultured in vitro in the presence of Interleukin-2 and irradiated feeder cells to propagate graft-infiltrating lymphocytes. A correlation was seen between the frequency of lymphocyte growth and the degree of cellular infiltration of the biopsies. In this study, 43 of 113 (38%) histologically negative biopsies obtained from 55 patients during the first month post-transplant yielded lymphocyte cultures. The cumulative incidence of subsequent histological rejection was considerably higher in patients with such grower biopsies than in patients with nongrower biopsies. In the grower group, we were able to obtain data on alloreactivity of 32 lymphocyte cultures assayed by primed lymphocyte testing (PLT). The presence of donor-specific PLT reactivity in the cultured lymphocytes was associated with an additional risk for subsequent histological rejection. These findings suggest that the in vitro culturing of histologically negative endomyocardial biopsies will identify patients at increased risk for developing heart transplant rejection.

Local Immunosuppression With Budesonide After Liver Transplantation In The Rat: A Preliminary Histomorphological Analysis

BACKGROUNDnIn this study we have analyzed the local immunosuppression with budesonide, a topically selective glucocorticosteroid, in rats after orthotopic liver transplantation. Because of its high first-pass hepatic clearance budesonide can be given orally, achieving high intrahepatic and low systemic concentrations.nnnMETHODSnUsing an acute rejection model from Dark Agouti (DA) to Lewis rats, the histomorphological degree of rejection was assessed on histological sections at the ninth postoperative day.nnnRESULTSnLivers of the DA to Lewis study group without immunosuppression revealed severe allograft rejection with vast cellular infiltrates, massive endothelialitis, and hepatocyte necrosis. In the three budesonide study groups (250 microg, 500 microg, and 1 mg/kg/day) a moderate to mild liver allograft rejection was seen. Rejection was most prominent in the 250 microg group, whereas the 1 g group showed almost no signs of rejection, similar to the Lewis to Lewis control group. Aspartate and alanine transaminase (sGOT, sGPT) as well as alkaline phosphatase serum levels correlated with the degree of rejection, achieving highest levels in the DA to Lewis group without immunosuppression. Animals treated with 1 g of budesonide had serum levels similar to Lewis to Lewis control animals.nnnCONCLUSIONSnThese results implicate a beneficial effect of local immunosuppression with budesonide in rats based on the histomorphological degree of liver allograft rejection.

Renal effects of acute infrarenal aortocaval fistula.

Aortocaval fistula is an uncommon complication of abdominal aortic aneurysm rupture or penetrating abdominal trauma. Hemodynamic consequences of these large arteriovenous fistulas include increases in cardiac output and heart rate, with decreases in peripheral resistance and mean systemic arterial pressure. Physiologic sequelae of aortocaval fistulas have been investigated in experimental [9, 12, 21, 22, 24] as well as clinical [17, 20] settings. Altered renal function is a poorly understood but common consequence of aortocaval fistula [16, 18, 25, 27]. Acute changes in renal function are transient, resolving promptly with fistula closure [16, 24]. Although alluded to in previous works [15, 21], this phenomenon has not been subjected to extensive experimental study. The present investigation was designed to document carefully hemodynamic and renal effects of aortocaval fistulas in a canine model.

Effect of phentolamine on perfusate flow characteristics during renal preservation

Abstract Studies of the intrarenal distribution of perfusate during pulsatile hypothermic renal preservation have shown that donor agonal anoxia produces decreased perfusion flow to the cortex and an increase in medullary flow which is reversed by intraarterial infusion of phentolamine. Kidneys subjected to donor anoxia plus 40–50 min of warm ischemia also show similar cortical-medullary perfusion changes which are refractory to intraarterial phentolamine. The potential clinical consequences of changes in intrarenal perfusion and its treatment are discussed.

Circulation studies in experimental phlegmasia cerulea dolens.

Abstract A model of phlegmasia cerulea dolens in the canine hind limb was used to study the effects of heparin, sympathectomy, and venous thrombectomy plus heparin on limb hemodynamics. Only thrombectomy plus heparin restored nutrient blood flow and was associated with clinical recovery of the limb. This experimental model of phlegmasia appears to be an excellent tool for testing additional modalities of therapy for this serious disease.

The 2DG-neutral red test for completeness of vagotomy

Ever since vagotomy became an important part of modern peptic ulcer surgery, investigators have searched for a test that would reliably indicate the completeness of vagus nerve section. The insulin hypoglycemia test, originally advocated by Hollander [8], has remained the most widely utilized test for the completeness of vagotomy, but despite several modifications it’s reliability has been questioned in a number of reports [6, 13, 141. In addition, the Hollander test has only postoperative application and cannot be used intraoperatively . Two-deoxy-D-glucose (2DG) is a potent vagal stimulant, causing an increase in gastric acid secretion greater than that produced by insulin-induced hypoglycemia [4]. The remarkable safety and low incidence of side effects associated with 2DG have been fully investigated in other studies involving humans [4,9, 121. Neutral red is an azine dye that is secreted by the gastric parietal cells into the stomach lumen [l], but only in the presence of intact vagal innervation to the stomach [lo]. Neutral red has likewise been shown to be safe for human use [7]. The present study is an attempt to use 2DG and neutral red in combination as a test for completeness of vagotomy both intraoperatively and postoperatively.