Role of endovascular intervention in patients with diabetic foot ulcer and concomitant peripheral arterial disease

AIM

The aim of this study was to evaluate wound healing, major amputation and mortality in patients with diabetic foot ulcer and peripheral arterial disease (PAD), and to compare the group decided to have an endovascular intervention with groups referred to conservative treatment or to those judged as unreconstructable.

METHODS

A retrospective two-year review of all patients with diabetic foot ulcers and PAD presented at an interdisciplinary diabetic foot round 2006-2007 at Malmö University Hospital, Sweden, was performed. Independent predictive factors of insufficient ulcer healing, amputation and mortality during follow-up were analysed according to treatment decisions at the diabetic foot round.

RESULTS

A total of 135 limbs in 115 consecutive diabetic patients with foot ulcers were included. Median age was 73 years and 41% were women. During a median follow-up time of 17 months, 44% of the ulcers did not heal, 15% of the limbs underwent major amputation and 42% died. Ulcer depth with a Wagner grade ≥3 (hazard ratio [HR] 5.8; 95% confidence interval [CI] 2.6-12.9), CRP (HR 1.007; 95% CI 1.002-1.012, and impaired run-off (HR 3.0; 95% CI 1.03-8.9) were independent risk factors for incomplete wound healing. The three treatment decision groups: attempt for endovascular leg revascularization (N.=75), conservative (N.=42) and unreconstructable (N.=18) showed no significant difference in terms of wound healing, major amputation or death.

CONCLUSION

Patients with diabetic foot ulcers and concomitant PAD are at high risk for limb loss and premature death. Ulcer depth, CRP and impaired run-off are independent risk factors for incomplete wound healing. There is an apparent need for prospective controlled studies to better define the role of endovascular therapy in this subset of diabetic foot ulcer patients.

Plasma concentrations of mycophenolic acid acyl glucuronide are not associated with diarrhea in renal transplant recipients

The aim of this study was to determine whether plasma concentrations of the acyl (AcMPAG) and phenolic (MPAG) glucuronide metabolites of mycophenolic acid (MPA) were related to diarrhoea in renal transplant patients on mycophenolate mofetil (MMF) with cyclosporine (CsA) or tacrolimus (TCL). Blood samples (0, 30, 120 min) were taken at days 3, 10, week 4, months 3, 6 and 12 for determination of MPA, MPAG and AcMPAG. MPA-AUC was estimated using validated algorithms. Two hour AUCs were calculated for MPAG and AcMPAG. Immunosuppressive therapy consisted of CsA/MMF (n= 110) and of TCL/MMF (n= 180). In 70/290 (24%) patients 86 episodes of diarrhoea were recorded during 12 months. Significantly more patients on TCL (31.1%) suffered from diarrhea compared to CsA (12.7%). MMF dose, MPA-AUC and the 2 h AUCs of MPAG and AcMPAG did not differ between patients with and without diarrhoea. Plasma AcMPAG and MPAG concentrations were substantially higher in patients on CsA compared with TCL, while MPA-AUC was lower in the former group. These data support the concept that CsA inhibits the biliary excretion of MPAG and AcMPAG, thereby potentially reducing the risk of intestinal injury through enterohepatic recycling of MPA and its metabolites.

Bicêtre hospital experience with sirolimus-based therapy in human renal transplantation: the Sirolimus European Renal Transplant Study

In 11 European centers, first cadaveric renal allograft recipients were randomized to CsA (n = 42) or sirolimus (n = 41). Dosing of these agents was concentration-controlled and open-labeled. All patients received corticosteroids and azathioprine. At 12 months, graft survival (98% sirolimus vs 93% CsA), patient survival (100% vs 98%), and incidence of biopsy-confirmed acute rejection (41% vs 38%) were similar. Serum creatinine was lower with sirolimus, significantly (P </=.05) so at 3 and 4 months, and serum uric acid and magnesium were normal. Laboratory abnormalities were reported significantly more often with sirolimus, which included hypertriglyceridemia (51% vs 12%), hypercholesterolemia (44% vs 14%), thrombocytopenia (37% vs 0%), leukopenia (39% vs 14%), and, of lesser importance, increased liver enzymes and hypokalemia. These abnormalities improved 2 months after transplantation when the sirolimus target trough level was lowered from 30 to 15 ng/mL. Occurrence of cytomegalovirus was comparable (14% vs 12%), but incidence of herpes simplex (24% vs 10%, P =.08) and pneumonia (17% vs 2%, P =.03) were higher with sirolimus. No gingival hyperplasia was seen with sirolimus, tremor was rare, and hypertension was less frequent (17% vs 33%). Two malignancies were observed with CsA, none with sirolimus. Results at 12 months suggest that sirolimus can be used as base therapy in the prophylaxis of acute renal transplant rejection, and has a safety profile that differs from that of CsA.

Circulating soluble vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 in immunocompetent and renal transplant patients: correlation with cytomegalovirus disease and renal function

The plasma levels of the soluble adhesion molecules, soluble vascular cell adhesion molecule-1 (sVCAM-1) and intercellular adhesion molecule-1 (sICAM-1), were measured before and after transplantation in 26 renal transplant recipients, and in 173 longitudinally collected samples in 17 of the patients. The patients were carefully monitored for the presence of cytomegalovirus (CMV) infection and rejection. Forty healthy blood donors and 12 otherwise healthy subjects with symptomatic primary CMV infections served as controls. During CMV disease, plasma levels of sVCAM-1 and sICAM-1 were elevated in both renal transplant patients and otherwise healthy subjects with CMV disease. The sVCAM-1 levels were strongly elevated before transplantation in renal transplant recipients and correlated with creatinine levels. Increased sVCAM-1 levels were also registered during rejection episodes. CMV disease, per se, is associated with markedly increased levels of sVCAM-1 and sICAM-1. There is also a correlation of sVCAM-1 levels with serum creatinine levels. Thus, the presence of CMV infection and renal function are factors that must be considered in further studies of soluble adhesion molecules.

Sirolimus allows early cyclosporine withdrawal in renal transplantation resulting in improved renal function and lower blood pressure

INTRODUCTION

This study evaluated whether cyclosporine (CsA) could be eliminated from a sirolimus (Rapamune, rapamycin, SRL)-CsA-steroid (ST) regimen at 3 months.

METHODS

This was an open-label study conducted in Europe, Australia, and Canada. Upon enrollment, 525 primary (90%) or secondary (10%) renal allograft recipients with cadaveric (89%) or living (11%) donors received 2 mg of sirolimus (troughs>5 ng/ml), CsA, and steroids. At 3 months+/-2 weeks, eligible patients were randomized (1:1) to remain on SRL-CsA-ST or to have CsA withdrawn and therapy continued with SRL (troughs 20-30 ng/ml)-ST.

RESULTS

At 12 months, overall graft and patient survival were 89.1% and 94.9%, respectively. In the 430 (82%) randomized patients, there was no difference in graft survival (95.8% vs. 97.2%, SRL-CsA-ST vs. SRL-ST) or patient survival (97.2% vs. 98.1%, respectively). The incidence of biopsy-confirmed primary acute rejection was 13.1% during the prerandomization period. After randomization, the acute rejection rates were 4.2% and 9.8% for SRL-CsA-ST and SRL-ST, respectively (P=0.035). Renal function (calculated glomerular filtration rate, 57 vs. 63 ml/min, P<0.001) and blood pressure significantly improved when CsA was withdrawn. Hypertension, CsA nephrotoxicity, hyperuricemia, and Herpes zoster occurred statistically more frequently in patients remaining on CsA, whereas thrombocytopenia, abnormal liver function tests, and hypokalemia were reported more often for SRL-ST therapy.

CONCLUSION

Sirolimus, CsA, and steroids for 3 months posttransplant, followed by elimination of CsA, is a safe and effective alternative to continuous therapy with sirolimus, CsA, and steroids that can result in better renal function and lower blood pressure.

Dose optimization of mycophenolate mofetil when administered with a low dose of tacrolimus in cadaveric renal transplant recipients

BACKGROUND

Supplementation of immunosuppressive therapy with mycophenolate mofetil (MMF) has been found to reduce the rate of acute rejection in renal transplantation. We report a dose-finding study for MMF when administered in combination with low-dose tacrolimus and corticosteroid prophylaxis in cadaveric renal transplant recipients.

METHODS

Two hundred thirty-two patients at 16 centers were enrolled in this randomized, parallel-group study. The three treatment groups were tacrolimus and corticosteroids (MMF-0 group, n=82); tacrolimus, corticosteroids, and 1 g of MMF daily (MMF-1 g group, n=79); and tacrolimus, corticosteroids, and 2 g of MMF daily (MMF-2 g group, n=71). Study duration was 6 months, and patients were followed up for patient and graft survival for 12 months.

RESULTS

At 6 months posttransplantation, daily doses of 1 g and 2 g of MMF were associated with significantly lower rates of acute rejection compared with tacrolimus alone. The Kaplan-Meier rates were 48.5%, 24.9%, and 22.9%, respectively, for the three treatment groups when acute rejection was determined by clinical criteria (P=0.007). At month 12, patient survival rates were 100%, 97.5%, and 97.2% and graft survival rates were 90.2%, 92.4%, and 93.0% for the MMF-0 group, MMF-1 g group, and the MMF-2 g group, respectively. Gastrointestinal adverse events and leukopenia were higher in the MMF groups, especially in the MMF-2 g group (P<0.05).

CONCLUSIONS

Low-dose tacrolimus combined with a MMF dose of 1 g daily and corticosteroids provided an optimized efficacy and safety profile. A higher dose of MMF (2 g) was associated with greater toxicity without a significant improvement in efficacy.

Sirolimus (rapamycin)-based therapy in human renal transplantation: similar efficacy and different toxicity compared with cyclosporine. Sirolimus European Renal Transplant Study Group

BACKGROUND

Sirolimus (rapamycin) is a potent immunosuppressant with a mechanism of action different from cyclosporine (CsA) or tacrolimus.

METHODS

In 11 European centers, first cadaveric renal allograft recipients were randomized to CsA (n=42) or sirolimus (n=41). Dosing of these agents was concentration-controlled and open-labeled. All patients received corticosteroids and azathioprine.

RESULTS

At 12 months, graft survival (98% sirolimus vs. 90% CsA), patient survival (100% vs. 98%), and incidence of biopsy-confirmed acute rejection (41% vs. 38%) were similar. Serum creatinine was lower with sirolimus, significantly (P< or =0.05) so at 3 and 4 months, and serum uric acid and magnesium were normal. Laboratory abnormalities reported significantly more often with sirolimus included hypertriglyceridemia (51% vs. 12%), hypercholesterolemia (44% vs. 14%), thrombocytopenia (37% vs. 0%), leukopenia (39% vs. 14%), and, of lesser importance, increased liver enzymes and hypokalemia. These abnormalities improved 2 months after transplantation when the sirolimus target trough level was lowered from 30 to 15 ng/ml. Occurrence of cytomegalovirus was comparable (14% vs. 12%); incidences of herpes simplex (24% vs. 10%, P=0.08) and pneumonia (17% vs. 2%, P=0.03) were higher with sirolimus. No gingival hyperplasia was seen with sirolimus, tremor was rare, and hypertension was less frequent (17% vs. 33%). Two malignancies were observed with CsA and none with sirolimus.

CONCLUSIONS

Results at 12 months suggest that sirolimus can be used as base therapy in the prophylaxis of acute renal transplant rejection, and has a safety profile that differs from CsA.

Prospective study of calcium homeostasis after renal transplantation

Nineteen consecutive patients receiving renal transplants underwent prospective evaluation of their calcium homeostasis for 1 year after transplantation to characterize indices of hyperparathyroidism (HPT) amelioration. All but one underwent dialysis, and six had vitamin D supplementation before grafting. The rapid falls in serum creatinine concentrations and increased creatinine clearances the first weeks after grafting were accompanied by rapidly reversed hypercalcemia and hypermagnesemia, induced hypophosphatemia, maintained parathyroid hormone (PTH) excess and calcitriol deficiency, and decreased alkaline phosphatases. At 3 months when the serum calcitriol had started to rise, serum PTH levels were the lowest and parathyroid responses to induced hypocalcemia the least abnormal. This was coupled to peaks in serum calcium, 24-hour urine calcium excretions, and serum alkaline phosphatase levels. All patients had subnormal creatinine clearances at the study end, and normal serum PTH occurred in only seven of them. Arbitrary subgrouping of the material was performed according to posttransplant creatinine clearance and serum PTH levels. More satisfactory graft function related to lower serum PTH values and less abnormal parathyroid responses to induced hypocalcemia, earlier and higher rises in serum calcitriol, and higher urine calcium excretion. Patients with mild HPT at the study end generally had higher creatinine clearance, lower serum PTH, calcium, and alkaline phosphatase values, and lower urine calcium excretion. Moreover, they had fewer prevalent signs of radiologic bone involvement before grafting. These temporal diversities in conjunction with the variable graft function and intensity of immunosuppression provide a complex interaction in renal transplant recipients, which should be considered in the light of improved function of the PTH/PTHrP receptor in bone and kidney and cation receptors in the parathyroid and kidney.

Kinetics and dynamics of single oral doses of sirolimus in sixteen renal transplant recipients

Sirolimus is a new immunosuppressive drug that has been evaluated in animal experiments. The current study was conducted on humans with reformulated sirolimus in doses from 3 mg/m2 to 15 mg/m2. Sixteen renal transplant recipients were included in this phase I study to determine the safety, tolerance, and preliminary pharmacokinetics of increasing single doses of orally administered sirolimus. All 16 patients had stable renal graft function after a renal transplant at least 6 months before the study. Basal immunosuppression consisted of cyclosporine and prednisolone (n = 10) or cyclosporine, azathioprine, and prednisolone (n = 6). Four groups (I, 3 mg/m2; II, 5 mg/m2; III, 10 mg/m2; IV, 15 mg/m2) of four patients were assigned randomly to receive sirolimus (n = 3) or placebo (n = 1). Among the 12 patients who received sirolimus, five had mild transient study events such as headache, nausea, mild dizziness, hypoglycemia, epistaxis, and decrease in platelets. No serious adverse events occurred and no nephrotoxic effects could be related to the single dose administration of sirolimus. The only study event that was judged as probably related to sirolimus was the single case of thrombocytopenia. The other events were evaluated as possibly related. Thrombocytopenia occurred at the highest dose level (15 mg/m2 sirolimus). In two of the patients in the placebo group, slight elevations of liver enzymes and serum amylase were seen. Blood and plasma sirolimus concentrations were analyzed by an electrospray-high performance liquid/mass spectrophotometric (ESP-HPLC/MS) method Sirolimus showed an extensive red blood cell distribution with a mean blood/ plasma ratio of 49.1. The elimination half-life ranged from 43.8 to 86.5 hours (mean 56.9 hours). The Cmax and the area under the concentration versus time curves (AUC) correlated reasonably with doses from 3 to 15 mg/m2. The oral dose clearance ranged from 42 to 339 ml/h.kg. No clinically significant differences were seen in the trough concentrations of cyclosporine or the AUCs before and after the administration of sirolimus. Administration of single oral doses of sirolimus from 3 to 15 mg/m2 was safe and well tolerated in stable renal transplant recipients. Thrombocytopenia may be the dose-limiting toxicity. Additional phase II and phase III clinical trials will define the immunosuppressive efficacy of sirolimus.

A prospective study of rapid methods of detecting cytomegalovirus in the blood of renal transplant recipients in relation to patient and graft survival

Eighty-five renal transplant recipients were prospectively monitored for CMV infection up to 4 months post-transplantation by virus isolation from leukocytes, CMV antigen detection (pp65) in peripheral blood leukocytes (PBL), polymerase chain reaction (PCR) of alkaline treated plasma (P-PCR), PCR of extracted DNA from PBL (L-PCR) and serology. Additionally univariate and multivariate analyses of risk factors for patient and graft survival up to 4 yr post-transplantation were performed. The incidence of CMV infection was 78% and of CMV disease 33%. Antigen detection in PBL was positive before or at onset of symptoms in 23/24 (96%) evaluable patients with CMV disease. The corresponding figures for virus isolation were 22/24 (92%), P-PCR 21/24 (88%) and for L-PCR 18/24 (75%). The percentage of negative samples in patients without CMV disease was 89% for the antigen test, 92% for L-PCR and 83% for virus isolation and P-PCR. One rapid test (antigen test, P-PCR or L-PCR) was positive at a median of 16 d before the onset of symptoms. The antigen test was generally the first rapid test to become positive. CMV disease did not affect graft survival in the multivariate analysis but was associated with decreased patient survival.

Cytomegalovirus (CMV) DNA amplification from plasma compared with CMV pp65 antigen (ppUL83) detection in leukocytes for early diagnosis of symptomatic CMV infection in kidney transplant patients

BACKGROUND

Rapid laboratory methods for the early detection of cytomegalovirus (CMV) are needed for the prevention of CMV disease in transplant recipients. These methods should not only be able to detect the virus but also be highly predictive for CMV disease.

OBJECTIVE

The clinical value of a simple and rapid nested plasma polymerase chain reaction (PCR) was evaluated by comparing the results with CMV pp65 antigen detection in leukocytes (CMV antigenemia assay), virus isolation from leukocytes, CMV IgG and IgM antibody response and clinical data.

STUDY DESIGN

A total of 471 EDTA blood samples were collected from 85 kidney transplant patients during a 3-4 month period after transplantation. CMV DNA was amplified directly from 10 microliters of plasma while 150000 separated leukocytes were stained for CMV pp65 antigen by each of two monoclonal antibodies. A total of one million leukocytes were used for virus isolation. The PCR protocol used in the present study involves a simple alkaline lysis technique for isolating DNA directly from plasma which is easy and rapid to perform.

RESULTS

Twenty-eight patients developed symptomatic CMV infection while asymptomatic infection occurred in 29 patients. CMV pp65 antigen detection had a 75% sensitivity and a 57% positive predictive value for CMV disease development, compared with 64% and 79% sensitivity and 49% and 46% positive predictive value for CMV DNA and viremia, respectively. The median time until detection of CMV in patients with symptomatic CMV infection was 26 days after transplantation, compared with 49 days in asymptomatic patients by any of the methods used. Early appearance (within 8 weeks) of CMV pp65 antigen and CMV DNA had high predictive values for symptomatic infection; repeated detection of pp65 antigen and CMV DNA were more common in symptomatic patients.

CONCLUSIONS

CMV antigenemia assay and plasma PCR can be used for pre-symptomatic diagnosis of CMV infection. Virus isolation and CMV serology in most cases provide a post-symptomatic diagnosis. The best marker for monitoring kidney transplant patients might be the quantitative CMV antigenemia assay.

Rescue therapy with tacrolimus (FK 506) in renal transplant recipients--a Scandinavian multicenter analysis

All renal allograft recipients (n = 32) in Sweden and Norway who were converted from cyclosporin (CyA)-based immunosuppression to FK 506 (tacrolimus) between October 1992 and June 1995 were analyzed retrospectively. The reasons for conversion were acute refractory rejection (n = 21), chronic rejection (n = 4), and suspected CyA toxicity (n = 6); one patient was converted for psychological reasons. The mean time from transplantation to conversion was 29 (range 1-243) weeks and there was a mean follow-up of 46 (2-143) weeks. Overall graft survival was 59%, with graft survival 52% in patients converted because of acute rejection, 50% in patients converted because of chronic rejection, and 83% in patients converted because of CyA toxicity. There was no significant correlation between preconversion serum creatinine and outcome. Seventy-two percent of the patients had significant side effects during FK 506 treatment, the most frequent ones being neurological and gastrointestinal symptoms. These improved after dose reduction. Two patients became overimmunosuppressed and developed lymphoma. One patient died of the primary kidney disease, hemolytic uraemic syndrome. We conclude that FK 506 therapy is able to salvage kidneys with acute refractory rejection and that it is an alternative in patients with CyA toxicity. However, the risk of overimmunosuppression must be considered.

Is kidney transplantation in sensitized recipients justified?

The objective of the study was to determine if it is justified to use the scarce resources of cadaveric kidneys on HLA-sensitized patients, by reviewing the initial and long-term outcome of cadaveric renal transplantation at Uppsala University Hospital, Sweden. Between January 1988 and December 1994, 402 renal transplantations were performed. The patients were divided into one group of sensitized recipients (peak panel antibody reactivity > or = 25%; n = 84) and a second of non-sensitized recipients (panel reactive antibodies < 25%; n = 318). The groups were comparable in terms of recipient and donor age, gender, HLA-A, -B and -DR mismatches and numbers of diabetics. None of the sensitized patients received a six-antigen-matched kidney. For the non-sensitized group, life table analysis showed a 1-year actuarial graft survival (GS) of 91.8% and a 4-year GS of 84.4%. The corresponding GSs for the sensitized group were 79.9% and 68.7%, respectively (P < 0.01). The statistical significance vanished if patients with primary non-function were excluded. When excluding donors above 55 years of age, kidneys with cold ischemia time above 20 h, and two-antigen (HLA-DR) mismatches, there was no detectable difference between the non-sensitized and sensitized groups at 1-year or 4-year GS. Although there is a statistical significance in GS between non-sensitized and sensitized recipients of a kidney transplant, this does not differ from other risk groups such as diabetics, rheumatoid disease sufferers or elderly recipients. We therefore conclude that the sensitized patient should be accepted on the waiting list for a kidney transplant and that it is worthwhile to do the utmost to transplant this category of patients. Our data indicate that kidney GS in sensitized recipients is more affected by negative risk factors such as older donors, long cold ischemia time and two-antigen HLA-DR mismatch, than the non-sensitized recipient. To improve the outcome, those negative factors should be avoided or reduced.

Chlorpromazine, quinacrine, and verapamil as donor pretreatment in liver preservation, tested in the isolated perfused rat liver

Rats were pretreated with a single iv dose of chlorpromazine (CPZ) 3 mg/kg, verapamil 1 mg/kg, or quinacrine 2 mg/kg. Livers were taken out and perfused with University of Wisconsin (UW) preservation solution and stored on ice for 48 h in the UW solution before reperfusion with erythrocyte-free and colloid-free Krebs-Hanseleit buffer at 38 degrees C in a nonrecirculating perfusion system for 2 h. CPZ- and quinacrine-pretreated livers produced significantly more bile than control livers and also released significantly less alanine aminotransferase into the perfusate at 30, 60, and 120 min of reperfusion. Aspartate aminotransferase levels were lower at 30 and 60 min of reperfusion for CPZ-pretreated livers but not at 120 min. The only difference between groups concerning lactate dehydrogenase (LDH) release into the perfusate was that CPZ decreased the amount of LDH released at 60 min. Total tissue water or tissue electrolyte content of the liver tissue at the end of the reperfusion did not differ between groups. In conclusion, verapamil was ineffective when given as single dose iv pretreatment to the liver donor but pretreatment with CPZ or quinacrine appeared to improve the function of the preserved liver.

Experience with vascular access for acute renal failure: using Buselmeier shunt and femoral vessel catheter

Three types of vascular access were evaluated over a period of 2 years, January 1987-December 1989, in 76 critically ill acute renal failure (ARF) patients. The Buselmeier shunt comprised 75% of the acute vascular access which were utilized, the cannulation of the femoral vessel 23% and the Scribner shunt 2%. The Buselmeier shunt was successfully used alone (mainly in the forearm) in 58 patients for continuous arteriovenous hemofiltration, continuous arteriovenous hemodialysis and intermittent hemofiltration. Thrombosis was noted in 7% of the shunts, where the majority needed a new shunt either on the same or the contralateral arm. Blood leakage was noted in 2%, hematoma in 1%, and accidental bleeding in 1% of the shunts. This study showed that the Buselmeier shunt is more used in our center, most likely because it is easy to bypass the hemodialysis filter by the staff nurse in case of clotting. No major complications were noted even if kept in place for a longer period of time. It offers adequate blood flow for continuous renal replacement therapy and intermittent hemofiltration in ARF.

Rapidly proliferative arteriopathy in cyclosporin-induced permanently surviving rat cardiac allografts simulating chronic vascular rejection

In an attempt to create a model of chronic rejection in rat, cardiac allograft transplantation was performed of hearts from PVG rats to DA rats treated with cyclosporin, 20 mg/kg body weight per day for 14 days and thereafter no immunosuppressive therapy. Experiments were made in 83 rats fed on a normal diet and in 24 rats fed on a diet containing an additional 0.5% cholesterol. Rats on the normal diet showed moderate signs of acute rejection during the first 20-40 days and grafts were lost in acute rejection during this period of time. However, after 2-3 months no signs of acute rejection were present. On the contrary, excessive proliferative changes of the vascular intima and endocardium along with fibrosis and fibrin deposition appeared and was progressive until 6 months post-transplantation. These morphological changes are similar to those found in chronically rejected organs like heart and kidney. In rats fed on a cholesterol diet after cessation of cyclosporin, development of the vascular and endocardial proliferative changes appeared three to four times as fast and were on average fully developed within 4-6 weeks post cessation of cyclosporin treatment. The recipients' own hearts showed no signs of vascular or endocardial damage. It is thus concluded that two models of vascular and endocardial proliferative changes in cardiac allografts have been developed showing distinct similarities to chronic vascular rejections seen in the clinical transplantation and with apparent similarities to severe arteriosclerosis. The models could be useful in the investigation of pathogenesis and therapeutical means for preventing chronic vascular damage in transplanted organs and arteriosclerosis.

Preservation of dog liver, kidney, and pancreas using the Belzer-UW solution with a high-sodium and low-potassium content

The UW solution developed for cold storage of the liver, pancreas, and kidney was used in a modified form in this study and tested in the orthotopic transplantation of dog livers, kidneys, and pancreases preserved for 48 hr. The modification was the alteration of the concentrations of potassium and sodium. The original UW solution contained 120 mM K+ and 30 mM Na+. In this study the Na+ was 140 mM and the K+ only 9 mM, all other agents were identical to the original UW solution. Six of 11 dogs survived with livers preserved for 48 hr. The five deaths were due to technical complications and unrelated to preservation failure. Postoperative AST and partial thromboplastin time (PTT) values were lower (statistically significant on days 1, 3, and 4) in livers preserved in the high Na+ UW solution than as previously shown in the high-k+ UW solution. Other measures of liver function (bilirubin and fibrinogen) were similar between the high-Na+ and high-K+ groups. Six dogs survived with kidneys preserved for 48 hr in the high-Na+ UW solution. The results were comparable to those obtained with the high K+ solution. Four of six dogs survived for up to 28 days with pancreases preserved for 48 hr. The two deaths were due to technical complications unrelated to preservation failure. Three of the four dogs had normal blood glucose values for one month, and intravenous glucose tolerances test on day 7 and 28 were identical to those obtained in pancreases preserved with the high-K+ UW solution. The high-Na+ version of the UW solution appears equally or slightly more effective for 48-hr organ preservation than the original high-K+ UW solution. The use of a high-Na+ UW solution reduces the problems of hyperkalemic cardiac arrest in in situ flushing of the donor for multiple organ harvesting and in transplantation of the liver. Thus, with this solution livers do not need to be flushed with a low K+-containing solution prior to transplantation.

Preservation of the canine liver for 24-48 hours using simple cold storage with UW solution

The results of a series of 29 orthotopic liver transplants in the dog are described. The livers were preserved in a new cold storage fluid, UW solution, and were successfully transplanted after periods of storage of 24, 30, 36, and 48 hr. All six animals transplanted after 24 hr survived beyond 5 days after transplantation and had excellent graft function. Four of six survived for at least 5 days after 30 hr of cold storage, and five of five after 36 hr. Five of six consecutive dogs that received transplants that had been cold-stored for 48 hr survived for 5 or more days. This solution represents a substantial advance over all existing cold storage solutions for liver preservation.

Morphology of rat cardiac allografts with permanent survival induced by antithymocyte globulin

In a rat heart transplantation model, permanent graft survival was achieved by anti-thymocyte globulin (ATG) treatment of Wistar Kyoto (WKy) recipients before grafting with PVG/c hearts. Nine hearts with palpable and electrocardiographic (ECG) function 8-20 months after transplantation were studied with histological and immunohistochemical methods. The dominating findings were fibrosis, intimal thickening, thrombosis of vessels, cellular infiltrates, and a high number of cells expressing class II antigens. These findings suggest that reactions compatible with a chronic rejection can be found in long-term surviving rat heart allografts. This rat model may thus be used in further studies of a chronic rejection process.

Effects of monoclonal anti-T cell antibodies on rat cardiac allografts

Monoclonal antibodies reactive with different T lymphocyte antigens were administered to rats receiving heart allografts. Ox 19 antibodies (directed to the rat Ly 1 equivalent) and Ox 8 antibodies (directed to the rat CD8 equivalent) both prolonged graft survival, whereas W3/25 (anti-CD4), Ox 6 (anti-Ia), and W3/13 (anti-pan T) antibodies did not affect graft rejection. Immunohistological studies were carried out on spleen and graft specimens in order to analyse further the mechanisms behind the prolongation of graft survival. The observed almost complete absence of Ox 8-reactive cells in the spleen after treatment with Ox 8 antibodies corroborates earlier observations that injection of moderate amounts of Ox 8 antibodies leads to complete elimination of suppressor/cytotoxic T cells from peripheral lymphoid organs and blood. The present data on graft survival therefore both support the notion that suppressor/cytotoxic T cells are involved in graft rejection, and suggest that these cells are not the only ones involved. An unexpected and as yet unexplained finding was that Ox 8-reactive molecules were found in large numbers on various inflammatory cells as well as on certain myocytes in the grafted hearts that had experienced a prolonged graft survival due to treatment with Ox 8 or Ox 19 antibodies.

Tissue distribution of T-lymphocytes and Ia-expressing cells in rat kidney grafts

In a rat kidney transplantation model, DA kidneys were transplanted into Lewis rats. Syngeneic Lewis transplantations were studied as controls. Histologic evaluation was made, and immunohistochemical staining with a single-staining peroxidase-antiperoxidase technique on frozen sections was performed after 2, 4, 6, and 8 days. Antibodies for Ia antigen (Ox 6), 'suppressor/cytotoxic' cells (Ox 8), pan-T cells (W 3/13), and 'helper/inducer' cells (W 3/25) were used. Allogeneic grafts were almost completely rejected in 8 days. Syngeneic grafts also showed lymphocyte infiltrates, somewhat later than allogeneic ones, but were not rejected. In these infiltrates W 3/25-positive cells dominated, being even more numerous than W 3/13-positive cells. Relatively fewer Ox 8-positive cells were seen in the infiltrates of syngeneic than in allogeneic transplants. Infiltrates occurred later in the renal medulla than in the cortex. Perivascular infiltrates with cells of all investigated phenotypes were seen earlier in allogeneic grafts than in syngeneic ones. All tubular cells within one renal tubule appeared either Ox 6-positive or -negative. With time, all tubules in the allogeneic transplants became Ox 6-positive. Some increase of Ox 6-positive tubules was also seen in syngeneic transplants.

Ureteral reflux and ileal conduit pressure following diversion with a reflux-preventing technique

Ileal conduit urinary diversion was performed with an antireflux technique, with nippling of the ureters into the segment, in 63 patients. The patients were then followed up for 52 +/- 25 months concerning urographic findings, infections and kidney function. Ureteroileal stenosis developed in 3 of 122 ureters and was surgically corrected. Roentgenologic examination for ureteral reflux was performed about a year postoperatively, and pressure measurements were made in the ileal segment. Reflux of contrast medium was seen in 48 ureters at pressure 51 +/- 30 mm Hg. When no reflux was seen, the maximum infusion pressure was 62 +/- 34 mm Hg. The basal pressure (preceding contrast infusion) was 24 +/- 29 mm Hg. Regular contraction waves with pressure rise in the ileal segment were registered, with duration 10-30 seconds. The study showed no connection between ureteral reflux and pressure in the ileal segment. Complications associated with the antireflux operating technique were few.

Antiviral activity appearing in serum of renal transplant recipients. Its possible relation to immunological rejection

Sera collected from a majority (15/16) of recipients of renal transplants occasionally contained low, but significant, levels of antiviral activity, maximally corresponding to 25-50 units of interferon-alpha per milliliter of serum in a bioassay. The exception was the only transplanted patient with a known cytomegalovirus infection, who demonstrated persistent high levels of antiviral activity corresponding to 200-400 interferon units/ml. Only the latter antiviral activity was sufficiently high for a partial characterization. It was pH 2 labile, did not have antigenic properties of interferon-alpha or beta, and may correspond to the lymphokine interferon-gamma. In consecutive serum samples from individual patients, the peaks of the antiviral activity occurred preponderantly in connection with clinical signs and consequent treatment of graft rejections. Interferon may, therefore, be a useful marker (at the serum level) of incipient graft rejection, and of certain viral infections, at least, provided that a more rapid sensitive and precise assay of this lymphokine is developed.

T-lymphocyte subsets and HLA-DR-expressing cells in rejected human kidney grafts

This communication describes an immunohistochemical analysis of rejected human renal allografts. T-lymphocyte subsets were identified in frozen tissue sections, by Leu 1 (anti-'pan' T lymphocytes), Leu 2a (anti-'cytotoxic/suppressor' T cells), and Leu 3a (anti-'helper/inducer' T cells) monoclonal antibodies. In addition, HLA-DR-positive cells were identified by simultaneous labelling with heterologous anti-HLA-DR antibodies. T cells dominated the cellular infiltrates in acute cellular rejection. Leu-3a-positive cells were more numerous than Leu-2a-positive cells. The Leu-3a-positive cells usually appeared in clusters, whereas the Leu-2a-positive cells appeared scattered in the tissue. HLA-DR-positive non-T cells were found within clusters of T 'helper/inducer' cells. The cell pattern shares many features with the findings in delayed-type hypersensitivity reactions.