David Anaise

An Approach To Organ Salvage From Non-heartbeating Cadaver Donors Under Existing Legal And Ethical Requirements For Transplantation

Effective utilization of nonheartbeating cadaver donor organs is limited by the time required to obtain the necessary family consent prior to organ retrieval (a delay of at least 4-6 hr); this exceeds by far the maximum tolerance of kidneys to warm ischemia. Measures that could theoretically permit use of such organs include: (1) rapid in situ flush cooling; (2) continued in situ kidney cooling until permission for donation is secured; and (3) cell-membrane stabilization of vital organs, with only minimal invasion of the donor body. These measures were tested experimentally in dogs. Hemorrhagic shock was produced in mongrel dogs. One hour after cessation of heartbeat, a rapid perfusion tube was placed into the femoral artery; it was advanced, and its balloon was inflated in the aorta above the renal vessels. The kidneys were then flushed in situ with 1000 cc of cold preservation solution containing a calmodulin inhibitor, trifluoperazine. Two other catheters were inserted percutaneously into the peritoneal cavity for continuous intraperitoneal cold perfusion. Core temperatures of 4 degrees C were maintained in situ in the kidneys for 5 hr. Six hours after cardiac arrest, the kidneys were removed and preserved ex vivo at 4 degrees C for 24 hr, and were then transplanted into their respective hosts (n = 11), where they sustained life uneventfully. This method requires a 2-inch incision in the groin of the prospective donor, and two small stab wounds of the abdomen; i.e., semi-invasive procedures which are commonly performed in emergency rooms. The perfused body could then be released to the family if donation is denied. The recently documented increased willingness of the public to donate organs when the termination of life support is not an issue, and court decisions that have authorized the performance of nondeforming diagnostic procedures in cadavers without consent, suggest that the salvage of transplantable semi-invasive procedures described in this study may be useful in helping to alleviate the current shortage of transplantable organs. This technique can provide the time needed for families to consider the option of organ donation from nonheartbeating cadaver donors in an unhurried and unpressured manner, while preserving the viability of vital organs during the decision-making process.

Immunohistologic analysis of human renal allograft dysfunction.

The value of percutaneous core needle biopsy in the immunohistological evaluation of renal allograft dysfunction was studied in 72 consecutive biopsies performed in 42 patients. The phenotypes of infiltrating cells mediating graft destruction were identified with monoclonal antibodies and immunoperoxidase staining techniques. Light microscopy, electron microscopy, and immunofluorescence staining were performed in all biopsies. Biopsies were divided into groups depending on their classification on the basis of standard histologic criteria, i.e., acute tubular necrosis (ATN), acute interstitial rejection, acute vascular rejection, chronic rejection and renal disease in native kidneys (RDNK) of nontransplant patients. Immunohistologic analysis of graft biopsies showed a significant increase in Leu 1 (pan-T cells), (P<0.001), Leu 2 (cytotoxic/suppressor cells) (P<0.001), and Leu 3 cells (P<.05) in acute interstitial rejection. The expression of BR antigen was significantly increased in both acute (P<.0.25) and chronic (P<.05) rejection, when compared with the findings in ATN biopsies. Leu M1 (monocytes/activated T cells) and Leu 10 (B cells/macrophages) were significantly increased (P<0.05 and P<.005, respectively) in acute interstitial rejection only. The helper/suppressor ratio of infiltrating cells showed no significant change in any clinopathologic category. There was no correlation between the cell populations infiltrating the graft and those monitored in the peripheral blood. Allograft mononuclear ceil infiltrates in cyclosporine (CsA) vs. azathioprine-treated patients revealed significantly fewer Leu 2 (P<.05) and Leu M1 (P<.05) cell populations in CsA patients during acute rejection. In 32 of these 72 biopsies (44.4%), the biopsy results provided a direct contraindication to the use of steroids, by allowing differentiation between allograft rejection and other causes of graft dysfunction. A total of 38% of the biopsies yielded a histological diagnosis that contradicted the clinical pre-biopsy diagnosis. All allografts showing evidence of severe small vessel disease and/or antibody-mediated rejection eventually were lost. These data highlight the usefulness of needle biopsy material as a guide to the study of intragraft immune events and to clinical management of recipients.

Value of percutaneous core needle biopsy in the differential diagnosis of renal transplant dysfunction.

The value of percutaneous core needle biopsy in the differentiation of rejection from other causes of renal allograft dysfunction, and its subsequent effect on patient management were assessed in 64 consecutive biopsies performed on 34 patients in whom the clinical diagnosis was was uncertain. A complete clinical, biochemical and radiographic assessment was made in each patient before biopsy. Only 1 biopsy (1.6 per cent) yielded tissue inadequate for evaluation, while another biopsy caused a renal artery pseudoaneurysm that ruptured and resulted in graft loss. In 27 of these 64 biopsies (42 per cent) the results differed from the pre-biopsy diagnosis and directly affected patient management, particularly the use of steroids. The remaining biopsy specimens were helpful to confirm uncertain clinical impressions, and allowed accurate counseling for patients and family. Biopsies were of special usefulness in separating acute rejection from complications, such as acute tubular necrosis, cytomegalovirus infections, recurrence of original disease, cyclosporin toxicity and acute superimposed-upon chronic rejection. Of 64 biopsies 22 (34.3 per cent) demonstrated the absence of rejection and 8 demonstrated chronic rejection (12.5 per cent), thereby averting the use of steroids in 46.8 per cent of the patients. All patients with evidence of severe small vessel disease and/or antibody-mediated rejection eventually lost the grafts, including 2 with cytomegalovirus glomerulopathy who also suffered such vascular changes. These data highlight the extreme usefulness of needle biopsy in the evaluation and management of renal allograft dysfunction.

Quantitative evaluation of renal excretion on the dynamic DTPA renal scan.

In order to evaluate the renal excretion quantitatively, the authors analyzed the Tc-99m DTPA renogram using mean transit time (MTT) with deconvolution analysis and compared it to the perfusion index. One hundred thirteen studies consisting of 25 normal, 11 obstruction, 35 transplant-norm, 12 transplant-obstruction, and 30 transplant-rejection were evaluated. In the non-transplant obstruction, MTT is significantly long (3.40 ± 0.85 minutes vs 2.02 ± 0.42 minutes) and has high sensitivity (100%) and specificity (93% 23/25) for the diagnosis of obstruction. In the transplant-obstruction, if the field of view includes both transplant and liver or spleen as a blood pool image, MTT has high sensitivity for the diagnosis (10/11) and for the follow up of obstruction (12/12), with the same specificity, but low sensitivity for rejection (25%). Perfusion index is of value in the diagnosis of rejection (73% specificity, 77% sensitivity) but is useless for the detection of obstruction (25%; specificity, 75%; sensitivity). The authors conclude that MTT is a useful marker for diagnosis and serial quantitative evaluation of renal obstruction. Also, they suggest the use of multiple techniques based on different principles for the complete evaluation of the renal scan.

PROTECTIVE EFFECTS OF TRIFLUOPERAZINE ON THE MICROCIRCULATION OF COLD-STORED LIVERS

Previous studies have shown a protective effect of trifluoperazine (TFP), a calmodulin inhibitor, upon the microcirculation of cold-stored kidneys. The present study points to similar beneficial effects of TFP on the microcirculation of cold-stored livers; 25 canine livers were preserved for 24 hr with Euro-Collins solution (EC) (n = 8), University of Wisconsin solution (UW) (n = 7), or UW + TFP (n = 10). The stored livers underwent heterotopic transplantation (HLTX); hepatic-artery and portal-vein pressure and flow were monitored; oxygen consumption and extraction were measured before HLTX and at 15-min intervals after reperfusion, for 1 hr. Mean hepatic-artery and portal-vein flow (HAF & PVF) prior to donor hepatectomy were 172 and 530 cc/min, respectively. Poor HAF and PVF occurred in EC-HLTX (mean 35, 175 cc/min, respectively). The damaged EC-flushed livers could not compensate to the decreased hepatic blood flow by increased oxygen extraction (oxygen consumption and extraction, 8.7 vol.% and 48%, respectively). Light and electron microscopy showed severe liver necrosis and periportal hemorrhages. Improved hepatic-artery and portal-vein flows were seen in UW HLTX (105 and 254 cc/min), and oxygen consumption and extraction were 16.4 vol.% and 66%, respectively. Liver biopsy taken just before reperfusion revealed well-preserved liver architecture. Liver biopsy obtained 1 hr after reperfusion revealed marked edema of the portal triad, sinusoid congestion, and hemorrhage. Electron-microscopy biopsies obtained during reperfusion at 15-min intervals revealed severe vasospasm of the terminal hepatic arterioles and progressive damage to the liver microcirculation. The addition of TFP to the UW-flush solution resulted in excellent protection of the liver microcirculation. Marked increase in hepatic-artery and portal-vein blood flow was noted after reperfusion (mean 167 and 421 cc/min, respectively (P 0.02 vs. UW: P 0.001 vs. EC). The recovery of metabolic activity was evident by the high oxygen consumption and extraction (25.8 vol.% and 80%, respectively). And serial liver biopsies obtained after reperfusion have shown excellent protection of liver architecture and the absence of hepatic arteriolar vasospasm. Taken together, these data suggest that the addition of TFP to the UW solution protects the liver microcirculation by rendering the hepatic microcirculation insensitive to vasospastic stimuli during reperfusion, thus permitting better metabolic recovery after transplantation.

Enhanced resistance to the effects of hypothermic ischemia in the preserved canine kidney.

Addition of trifluoperazine (TFP), a powerful calmodulin inhibitor to Collins flush solution has exerted a significant protective effect on the cold-preserved kidney, with successful autotransplantation of 80% of preserved kidneys (4 of 5) after 72 hr of storage. In contrast, use of Collins solution alone resulted in successful autotransplantation of only 33% (2 of 6) of kidneys after a similar period of preservation. In an attempt to analyze the significance of this result, the microcirculation of preserved kidneys was studied with injections of technetium-labeled micro spheres into the kidneys, followed by study with a noninvasive radionuclide scintiphotography (RNS) technique that does not interfere with subsequent transplantation of the kidney. Such studies demonstrate that prolonged cold preservation after flushcooling with Collins solution is associated with a progressive deterioration of the integrity of the microcirculation, resulting in poor flow to the renal cortex. In contrast, when TFP is added to the Collins solution, there are uniform increases in renal cortical flow in kidneys stored for 48 and 72 hr, with preservation of the integrity of the renal microcirculation. Biological testing shows a clear-cut correlation between these observations and the capacity of the tested kidneys to sustain life after re-transplantation. Further experiments suggest that the decreases observed in cortical flow in kidneys preserved in the cold for 72 hr are a consequence of cellular swelling, and not of a vasospastic response. The data support the conclusion that TFP exerts its protective effect on the basis of its membrane stabilizing capacity as a calmodulin inhibitor, and not through direct vasodilatation.

PRESERVATION TECHNIQUES FOR ORGAN TRANSPLANTATION: I. PROTECTIVE EFFECTS OF CALMODULIN INHIBITORS IN COLD-PRESERVED KIDNEYS

Interet de la trifluoperazine, inhibiteur de la calmoduline, dans les solutions de perfusion de reins a conserver. Les mecanismes daction de la calmoduline dans le metabolisme cellulaire devraient etre etudies de facon plus approfondie

Immunological consequence of renal transplantation and immunosuppression. I. Alterations in human natural killer-cell activity

The role and activity of natural killer (NK) cells following renal transplantation remain unknown. To monitor NK activity, a51Cr release of K-562 targets in prednisone-and azathioprine-treated patients receiving renal allografts was utilized. In 18 patients in whom NK activity was measured prior to and after transplantation, a significant diminution in NK activity within 3 weeks following transplantation was demonstrated compared to pretransplant values (34.71 vs 12.20%, respectively;P<0.001). In 11 subjects who had NK activity assayed at various intervals after transplantation but not prior to allografting, mean NK values were markedly lower (mean, 14.2%) than those of normal volunteers or patients maintained on hemodialysis (P<0.001). The latter two control groups demonstrated no difference (P = NS) in mean NK activity (39.46 vs 35.82%, respectively). In 5 of the 29 patients evaluated with good long-term graft function (mean, 2.7 years), restitution of normal NK activity was demonstrated. In two patients with bacterial infections, NK activity increased from 39.29 to 51.7% and from 13.54 to 20.00%. After infection, these values were 35.3% in the former and 3.39% in the latter. Viral infection did not appear to affect NK activity significantly. NK activity was increased in only one of seven patients with documented rejection episodes. In three of such patients, NK activity declined significantly following pulse methylprednisolone therapy. These results indicate that (1) NK-cell activity significantly decreases immediately after transplantation, probably as a result of immunosuppressive therapy; (2) NK activity does not appear to be stimulated by the alloreactive rejection process; (3) NK activity may be augmented in the course of bacterial but not viral infections; and (4) long-term allograft survival may be associated with a restoration of NK-cell levels in certain recipients.

Rectus Muscle Flap for Repair of Refractory Bladder Fistula Following Renal Transplantation: A Case Report

We report a case of refractory bladder fistula in a diabetic renal allograft recipient that recurred shortly after conventional operative repair without any detectable external cause. After reoperation and use of a vascularized rectus muscle flap the fistula closed and the patient has retained excellent graft function. It is suggested that this technique should be considered as the primary repair modality for bladder fistulas in diabetic recipients, when wound healing is impaired seriously as a consequence of the combined effects of diabetic microangiopathy and steroid therapy.

Multivariate and Boolean Factor Analysis of Immune Complex/Complement Deposits and their Effects on Renal Blood Flow During Allograft Rejection

The role of humoral immune factors in graft destruction is not fully understood. With immunofluorescence techniques the possibility of a specific pattern and/or clustering of immune complex or complement deposits was analyzed in 140 percutaneous kidney needle biopsies performed in 73 patients with renal allograft dysfunction. The results were correlated with concomitant alterations in renal blood flow as measured by cortical and global perfusion indexes and graft survival. The deposition of IgG, IgM, C3 and C4 correlated significantly with acute rejection confirmed by biopsy (p less than 0.05, less than 0.001, less than 0.02 and less than 0.001, respectively). Subsequent graft survival was compromised when IgA, IgG, IgM, C3, C4 and properdin were present together in biopsy specimens (p less than 0.05). There was a significant clustering of IgA with C3, of IgG with C3 and C4, and of IgM with C1, C3 and C4 (p less than 0.001). There also was a significant association among alterations in renal blood flow, deposition of IgA (p less than 0.05) and C4 (p less than 0.02), and graft outcome. Higher perfusion indexes, indicative of decreased blood flow, showed significant associations (p less than 0.007 and less than 0.04 for the cortical and global perfusion indexes, respectively) with a greater risk of graft loss. Although it primarily is a cellular event, the data suggest that acute rejection is associated with a deposition of various humoral factors that may mediate alterations in renal blood flow. The latter may affect graft function and structural integrity, and, thus, may show a direct correlation with the outcome of a graft.