Effect of delayed graft function and ALG on the circaseptan (about 7-day) rhythm of human renal allograft rejection.

Postimplantation records of 157 kidney transplant recipients with first rejection episodes within 50 days of surgery were studied. Of these 36 had living-related and 121 cadaver donors. Recipients of cadaver donor kidneys were divided into four subgroups: with and without postoperative acute renal failure (ARF), and with and without approximately two weeks of immunosuppression by antilymphoblast globulin (ALG) added to conventional therapy. All recipients with immediate function without ALG showed evidence of periodicity in probability of occurrence of rejection that was highly significant for a 7-day period beginning at the time of surgery. The remaining groups showed less significant periodicity or no significant periodicity beginning at the time of surgery, but they did show a highly significant circaseptan rhythm of rejection episodes beginning with cessation of ALG treatment or with onset of diuresis following ARF in the absence of ALG. It is suggested that clinical manifestation of the immunologic attack of recipient upon graft has an intrinsic development period of about 7 days beginning with implantation. However, initiation of the first period may be blocked by ALG or by low renal blood flow during ARF.

Effect of plasma proteins and buffer in flushing solutions on rat kidney preservation by cold storage.

The isolated rat kidney perfused at 37 C was used to evaluate the effect of adding plasma proteins to, and varying osmolality of, cold-storage flushing solutions with or without buffering. Addition of albumin improved immediate poststorage kidney function (glomerular filtration rate [GFR], fractional sodium reabsorption, and fractional protein clearance) of all flushing solutions tested after 6 hr and 24 hr of storage. At 6 hr, these improvements also correlated with less weight gain. Flushing solutions containing citrate and sulfate produced significantly better return of function after 24 hr of cold storage than Krebs' or Collins'-derived solutions. Osmolality was unimportant with solutions containing citrate. Collins' solution with reduced MgSO4 yielded better poststorage function than conventional solution. An all-citrate isotonic solution buffered with 15 mmol THAM preserved poststorage function at 48 hr better than a similarly buffered solution containing both citrate and sulfate. Loss of dry weight during storage and subsequent perfusion appeared to correlate, in these experiments, with loss of poststorage function. The isolated rat kidney provides discrimination among various flushing solutions. The technique might be useful in the assay of additional variables that might affect the quality of kidney preservation.

Use of the isolated perfused kidney model to assess the acute pharmacologic effects of cyclosporine and its vehicle, cremophor EL.

"Nephrotoxicity" secondary to cyclosporine and its clinically used vehicle, Cremophor EL, was examined in the isolated perfused rat kidney model. This model allows the serial determination of renal hemodynamic and tubular functional studies over a 3-hr duration using a normothermic, low hematocrit (13-15%) perfusion system. Initial studies indicated that the addition of small quantities of Cremophor EL resulted in marked renal vasoconstriction with decreased renal blood flow and deterioration in renal tubular function. These effects were highly significant and were of the same magnitude whether or not cyclosporine was present in the system. Cyclosporine was therefore examined after being dissolved in another vehicle, methanol. A 10% (v/v) amount of plasma was necessary in the perfusate to prevent significant adsorption of cyclosporine to the perfusion apparatus. Cyclosporine at concentrations below 100 ng/ml resulted in minor changes in renal hemodynamics. Beginning at 100 ng/ml glomerular filtration rate dropped significantly and renal vascular resistance increased three-fold. Fractional excretion of sodium significantly increased and the urine:plasma inulin ratio significantly decreased. We conclude that the clinically used drug vehicle, Cremophor EL, has significantly adverse effects on renal hemodynamics and tubular function. In addition, CsA causes similar renal toxicity in a dose-dependent fashion. Simultaneous administration of these two nephrotoxic agents could contribute to the high incidence of acute renal failure seen after transplantation. These observations suggest that an alternate vehicle with less renal toxicity might significantly decrease the incidence of this clinical problem.

Effect of cyclosporine and delayed graft function on posttransplantation erythropoiesis.

The effect of delayed graft function and immunosuppressive drugs on posttransplant erythropoiesis was studied prospectively in 18 living-related (LR) and 84 cadaver-donor (CD) recipients. Eight of 18 LR and 20 of 84 CD recipients received antilymphoblast globulin (ALG) in addition to azathioprine and prednisone. Sixty-four CD recipients received cyclosporine (CsA) with prednisone. In the absence of rejection reticulocytosis began 6.7 +/- 0.2 days following graft implantation in azathioprine-only-treated LR recipients. This was lengthened by ALG to 9.4 +/- 0.3 and 9.9 +/- 0.7 days in LR and CD recipients, respectively, whose grafts functioned immediately. Delayed graft function prolonged onset of reticulocytosis to 15.9 +/- 0.9 days in ALG-treated but not in CsA-treated recipients (5.8 +/- 0.4 days). The shortest latency was noted in CsA-treated recipients (4.9 +/- 0.5 days) with immediately functioning grafts. The earlier onset of reticulocytosis of CsA-treated recipients was followed by statistically significant blunting of peak reticulocytosis, which correlated with a slower rate of correction of anemia (delta Hct = 0.19/day) compared with non-CsA-treated recipients (delta Hct = 0.34/day). Early rejection was associated with abrogation of reticulocytosis and correction of anemia without regard to immunosuppressive regimen) until rejection was reversed. Erythropoietin (EPO) was measured sequentially in 5 patients with immediate function. In 4 of 5 cases changes in EPO preceded those in reticulocytosis. EPO rose from a mean of 13 mU/ml pretransplant to a peak of 50 within 3 weeks and decreased to 18 mU/ml within 6 weeks of graft implantation. At six months posttransplant, normalized reticulocyte counts were only 55% higher (1.75 vs. 1.13%) but hematocrit had increased from 26 +/- 1% to 42 +/- 1%. Hematocrit varied inversely with serum creatinine, which was highest in CsA-treated patients with initial delayed graft function. We conclude that correction of anemia posttransplantation is driven by EPO but other factors may also be important, that neither ATN nor ALG-therapy have clinically important effects on erythropoiesis, and that CsA reduced "effective" erythropoiesis and influences correction of anemia--particularly if delayed graft function complicates the initial course posttransplantation.

Diagnostic and prognostic significance of an increase in fractional protein clearance ratio before and during rejection of renal transplant.

We measured prospectively changes in fractional protein clearance ratio (CPr/CCr) in 21 live-related (LR) and 41 cadaver donor (CD) renal transplants before and during onset of first rejections. Fifty-three recipients manifested a rejection within the first post-transplant month. Fractional protein clearance increased in all patients during rejection. An increase in CPr/CCr prior to other evidence of impending rejection, and therefore clinically useful, required at least a 10-day rejection-free interval dated from onset of diuresis (whether diuresis was immediate or delayed by acute tubular necrosis (ATN)). Twenty-three of 25 nonantilymphocyte globulin (ALG)-treated CD transplants manifested clinical and laboratory signs of the first rejection episode prior to the 10th day of diuresis compared with 5 of 21 LR and none of 16 ALG-treated CD transplants. Persistence of elevated CPr/CCr despite treatment forecast graft loss (11 of 13), whereas a decrease in this ratio was associated with ultimate reversal of the rejection process.

Variables affecting birthweight and graft survival in 197 pregnancies in cyclosporine-treated female kidney transplant recipients.

Outcomes from 197 pregnancies in 141 female kidney transplant recipients were analyzed from data collected via questionnaires, hospital records, and phone interviews. All recipients were maintained on cyclosporine (CsA) before and during pregnancy. Of the livebirths, 54% were premature (< 37 wk) and 50% were low-birthweight (LBW) (< 2500 g). The incidence of recipient drug-treated hypertension (HTN) was 56%; preeclampsia, 29%; infections and complications 22%; and rejection during pregnancy and up to 3 mo. post delivery (rej.), 11%. Graft loss within 2 years of delivery occurred in 9% of recipients (GrL < 2). No recipients reported a pregnancy after a postpregnancy graft loss. Mean serum creatinine was reported before, during, and after pregnancy. Mean cyclosporine doses were similar in recipients during and after pregnancy. Data were analyzed by logistic regression using SAS. Outcomes included prematurity, LBW, rej., and GrL < 2. In a case-controlled study comparing a recipient group with graft dysfunction during pregnancy vs. a group with good graft function, there was a trend toward lower mean prepregnancy CsA doses (in mg/kg) in the graft dysfunction group. A decline in recipient graft function during pregnancy is associated with lower newborn birthweights and lower maternal graft survival in cyclosporine treated female kidney recipients. Pregnancy-related infections and complications are associated with rejection and graft loss in this population. Close monitoring of CsA dosing and serum creatinine levels during pregnancy and immediately postpartum is recommended as CsA dosage adjustment may be required.

National transplantation Pregnancy Registry--outcomes of 154 pregnancies in cyclosporine-treated female kidney transplant recipients.

Outcomes of pregnancies from 115 female kidney transplant recipients maintained on cyclosporine before and during pregnancy were obtained from questionnaires, hospital records, and telephone interviews. The mean age of conception was 29 years with a mean transplant interval of 2.2 years. There were 156 outcomes (2 sets of twins): ectopic 1%, therapeutic abortion 12%, miscarriage 16%, stillborn 2.6%, live birth 68.6%. The incidence of prematurity (< 37 weeks) was 56%, and that of low birthweight (< 2500 g) 49.5%. Complications occurred in 21.7% of newborns, but with only 1 neonatal death. Liveborn infants had a mean gestational age of 35.6 weeks (term 37-42 weeks) and a mean birthweight of 2407 g. The incidence of drug-treated hypertension prior to pregnancy was 51.7%; of diabetes prior to pregnancy, 11.7%; of preeclampsia, 24.8%; and of rejection during pregnancy or within 3 months postdelivery 14.5%. When infants born to women with or without a given risk factor were compared, mothers with pregnancy drug-treated hypertension had significantly lower-birth-weight infants (2250 vs. 2603 g, P = 0.028 by Wilcoxon). Similarly, mothers with prepregnancy creatinine > or = 1.5 mg/dl had smaller infants (2090 vs. 2505 g, P = 0.031 by Wilcoxon). There was a trend toward lower birth-weight in infants of diabetic recipients. Of 107 recipients interviewed, 12(11%) experienced graft loss, 8 associated with graft dysfunction or rejection during pregnancy. There was 1 graft loss during pregnancy due to rejection and 8 grafts were lost within 2 years of the pregnancy. There was one maternal death 4.3 years postpregnancy. For the 8 recipients who lost their graft within 2 years of pregnancy, outcomes included 1 miscarriage and 7 live births. The 7 live births had a mean gestational age of 35.7 weeks and a mean birth-weight of 2194 g. Five of 8 recipients who had graft loss within 2 years of pregnancy were in the drug-treated hypertensive group. Prepregnancy factors that appear to increase the risk to the newborn of a female kidney transplant recipient include maternal drug-treated hypertension, diabetes, and serum creatinine > or = 1.5 mg/dl. More data are needed before specific prepregnancy predictors for maternal graft loss can be determined in this population.

Estimation and characterization of the potential renal organ donor pool in Pennsylvania. Report of the Pennsylvania Statewide Donor Study.

The Pennsylvania Statewide Donor Study evaluated deaths under the age of 66 occurring in 149 participating hospitals in 1987. After elimination of 6146 patients from 11,983 based upon ICD-9 code criteria, an on-site medical record review was performed on 5603 patients. Each patient was assessed for organ donor suitability based upon brain death and medical suitability criteria--and, after a series of eliminations, 453 patients were found to have a moderate or higher potential as acceptable organ donors. An estimation of the organ donor rate was placed between 38.3 and 55.2 donors per million population per year, depending upon the stringency of organ donor criteria. Educational efforts targeted at physicians, patient's families and transplant surgeons will be necessary, however, to attain this maximal rate.

Adverse effect of splenectomy on the survival of patients with more than one kidney transplant.

Risk factors associated with death were identified in a cohort of patients who received 2 or more kidney transplants. Data on 19 variables were collected by chart review on 774 patients who received allografts between 1973 and 1980 at any one of 3 hospitals in Philadelphia. 124 of the patients received two or more transplants and were followed for a minimum of 1.5 years. Modified life table analyses of single variables indicated that 7 factors--splenectomy, donor source, age, transplant hospital, number of HLA mismatches, donor sex, and survival time of the prior graft--were significantly related to patient survival. Using all 19 variables, the proportional hazards model was fit to the data. The characteristics most related to survival were splenectomy (P less than .001), donor source (P = .0022), and age (P = .0015). The other 4 factors that were significant on univariate analysis were not significant in this multivariate analysis. The relative risk of death was 5.5 for patients who had had a splenectomy compared with those who had not had a splenectomy. Patients who had received more than one transplant were compared with patients who had received only one transplant, and a subset of recipients of primary transplants who returned to dialysis after primary graft failure. Survival of patients who had received one transplant was approximately the same as that of the retransplanted population. When the proportional hazards model was fit to the populations that received one transplant and compared with the model for the retransplanted group, only age and donor source were common to all three models. The effect of splenectomy on survival was significant for the total population of primary transplant recipients but had no effect on the survival of the subset of recipients whose kidney grafts had failed and were returned to hemodialysis. Infection accounted for 45% of the deaths among splenectomized, retransplanted patients. A higher percentage of septic deaths occurred in patients whose grafts were functioning at the time of death when compared with patients who had returned to dialysis after secondary graft failure. Although retransplantation alone is not associated with an increased mortality, retransplantation in splenectomized patients carries a high risk of death.

A comparison of the effects of cyclosporine versus antilymphocyte globulin on delayed graft function in cadaver renal transplant recipients.

There has been concern that cyclosporine's nephrotoxicity increases the incidence of delayed graft function (DGF), prolongs periods of oliguria, and reduces graft survival. In order to further study whether CsA should be used in DGF, we conducted a randomized prospective trial of the effect of CsA versus antilymphocyte globulin on the effects of DGF. Between 12/22/85 and 3/11/88, all patients with DGF after an initial 12-24 hr of CsA were randomized to either daily Minnesota ALG and prednisone or lower-dose CsA (10 mg/kg/day) and prednisone. Resolution of DGF was defined as a lack of dialysis dependency and a 25% fall in the serum creatinine (CR). If DGF was not resolved by 2 weeks, transplant renal biopsies were performed to assess the presence of occult rejection. CsA (10 mg/kg/day) was initiated in the ALG group only after resolution of the DGF. Of the 45 patients who recovered graft function, 19 received ALG and 26 received CsA. CsA significantly prolonged the duration of DGF (ALG 9.74 days, CsA 13.69 days, P = 0.035) but did not result in a prolongation of hospitalization. No difference in CR was found between the two groups at 1 month, 3 months, 6 months, or 12 months. Mean CR at 12 months was 1.98 mg/dl for ALG versus 1.96 mg/dl for CsA. Overall graft survival did not differ in the CsA and ALG groups (P = 0.33). CsA does slightly increase the duration of DGF as compared with ALG but has no effect on one-year serum CR or one-year graft survival. Since there appeared to be no harmful long-term effects of the slight lengthening of DGF, a lower-dose of CsA protocol with biopsy surveillance for occult rejection can be used in patients with DGF.

A high panel-reactive antibody rescue protocol for cross-match-positive live donor kidney transplants.

BACKGROUND: Alloimmunization can present a virtually insurmountable barrier to kidney transplantation. Past protocols to desensitize patients using plasmapheresis and cyclophosphamide have not been broadly applied because of the fear of complications, including high rates of immunologic failure. METHODS: Fifteen patients with a positive donor-recipient cross-match were desensitized with plasmapheresis to permit live donor (LD) transplantation under newer maintenance immunosuppressants. Pretransplant the patients received plasmapheresis three times weekly for a planned maximum of six treatments, plus intravenous hyperimmune globulin, tacrolimus, mycophenolate mofetil, and prednisone. Patients who were successfully desensitized and received transplants were given 10 days of OKT3 postoperatively. RESULTS: Eleven of the 15 patients became anti-human globulin cross-match-negative after one to five plasmapheresis treatments and underwent LD transplantation. Relatively low initial titers of donor-specific antibody were predictive of successful attainment of a negative cross-match. Few side effects and rejection episodes were observed. All transplant patients remain dialysis-free after 3-26 months of follow-up. CONCLUSION: A positive cross-match is not necessarily a contraindication to LD transplantation, especially for patients with low donor-specific alloantibody titers.

The shrinking renal replacement therapy "break-even" point.

BACKGROUND: This study examines the current cost of live donor (LD) transplantation at our institution, and compares it with that of dialysis. METHODS: The study population consisted of 184 consecutive adult recipients of laparoscopically procured LD kidney transplants. Cost-containment measures instituted during this series included elimination of routine postoperative antilymphocyte induction and an accelerated discharge clinical pathway with planned discharge of the recipient on postoperative day (POD) 2. Costs of the transplants to Medicare were estimated from hospital charges, readmission rates, and immunosuppressant usage. These were compared with published costs of dialysis to Medicare in terms of a fiscal transplant-dialysis break-even point. RESULTS: Kaplan-Meier patient and graft survival rates at 1 year were 97 and 93%, respectively. Among patients followed for at least 90 days and treated with no induction and either cyclosporine-mycophenolate mofetil or tacrolimus-mycophenolate mofetil, acute rejection rates were low (27.6 and 13.9%, respectively). In the last 124 patients, 32.3% were discharged by POD 3 and 71.8% by POD 6, with corresponding mean transplant hospital charges (excluding organ acquisition) of $11,873 and $17,350, respectively. The 30-day readmission rate for patients discharged on the accelerated pathway by POD 3 was only 16%. The least expensive subgroup in the present study (30% of patients) was that of patients discharged by POD 6 and not readmitted during the first year; the break-even point with dialysis costs was calculated as 1.7 years after the transplant. CONCLUSIONS: The cost of LD transplants can be safely reduced by elimination of routine postoperative anti-lymphocyte immune induction and by an early discharge clinical pathway. Uncomplicated LD kidney transplants, meaning those with a short length of stay in the hospital after transplantation and no need for readmission within the first year, accrue savings over dialysis within 2 years.

Insertion and recovery of a new retrievable vena caval filter. Work in progress.

A new retrievable inferior vena cava (IVC) filter was tested in nine pigs. Insertion was through a 14 French sheath using both the femoral and jugular approaches. All insertions were successful, and there was a 100% postinsertion IVC patency rate (8/8 pigs at one week and 1/1 pig at one month). Addition of an apical hook to the filter design allowed transjugular retrieval of two filters at one week postinsertion. Three of nine filters migrated to the upper IVC. The filter's design allows paraxial blood flow despite trapped thrombus and inhibits filter tilting. In vitro, the filter captured 95% to 100% of 5 X 5 mm clots. If problems with migration can be solved, the new filter may provide effective short- and long-term prophylaxis against pulmonary embolism.

Use of freshly isolated capillary endothelial cells for the immediate establishment of a monolayer on a vascular graft at surgery.

Endothelial seeding of vascular graft surfaces may lead to a less thrombogenic surface. We examined the feasibility of using microvessel endothelial cells derived from human fat for seeding purposes. Human fat was treated with collagenase for 24 minutes, washed, and purified in a Percoll gradient separation. This yielded 1.25 +/- 0.45 X 10(6) cells/gm of fat. After a 1-hour incubation on plasma-coated Dacron, 2.8 +/- 1.5 X 10(4) cells remained firmly adherent to the surface. When exposed to flow for 2 hours at a shear stress of 0 to 80 dyne/cm2, between 50% and 100% of the initially adherent cells remained adherent. Statistical analysis of this data failed to demonstrate a strong relationship between the number of adherent cells and the shear rate. Scanning electron microscopy demonstrated endothelial cells in various stages of attachment to the plasma-coated Dacron. Although most cells were still round and only focally attached to the surface, some cells were maximally flattened, forming cell-to-cell contact. Because of the high cell yield and the firm adherence characteristics, we conclude that microvessel endothelial cells may offer the possibility for confluent endothelial cell seeding of a graft at the time of surgical implantation without the need for cell culture.

Collagenase lot selection and purification for adipose tissue digestion.

Crude Clostridial collagenase (CCC) remains the most widely used enzyme for the digestion of tissues prior to cell isolation and culture. CCC contains numerous components in addition to specific collagenases and proteases. A chronic problem associated with CCC is significant lot variability which occurs with respect to the ability of different lots of CCC to digest tissue. We have evaluated numerous commercially available samples of CCC for their ability to digest human liposuction-derived SC fat. Digestion capacity was evaluated as the ability to release endothelial cells from fat as well as the ability of isolated cells to adhere to tissue culture plastic. A significant variation in digestion efficacy between lots of collagenase was observed. We subsequently purified CCC using a partial purification method with dialysis and centrifugation as well as a complete purification, using liquid chromatography, to remove all nonspecific proteases. While partially purified collagenase retained digestion capacity, pure collagenase exhibited reduced digestion capacity. Maximum digestion was achieved with pure collagenase when trypsin was added. The use of completely purified collagenase with trypsin is advantageous where all components in the enzyme digestion mixture must be known.

A porcine model for adipose tissue-derived endothelial cell transplantation.

The transplantation of endothelial cells represents a technology which has been suggested for applications ranging from improvement in function of implanted vascular devices to genetic therapy. The use of microvascular endothelial cell transplantation has seen increased use both in animal studies as well as clinical use. This report describes our techniques for the isolation and establishment of initial cultures of microvascular endothelial cells derived from porcine fat. A variety of anatomic sites within the pig were evaluated to determine the appropriateness of different sources of fat for endothelial cell isolation. The properitoneal fat was determined to be optimal due to the predominance of endothelium in this tissue and the ease of isolation of microvascular endothelium following collagenase digestion. The study of endothelial cell transplantation in the porcine model is now possible using the methods described for adipose tissue-derived microvessel endothelial cell isolation.

Greenfield filter in renal transplant patients.

Renal transplant patients in whom deep vein thrombosis and pulmonary embolism (PE) develop usually respond to heparin sodium treatment. A small percentage of transplant patients will require vena caval filter placement to prevent recurrent PE, and this report details our experience with two patients. In one patient there was contraindication to heparin, and in the other, a massive recurrent PE. Greenfield filters were inserted transvenously in these patients and found to be well tolerated. There was no evidence of renal compromise, recurrent PE, or other complications. Follow-up venograms confirmed the presence of patent vena cavas with properly positioned filtered. Autopsy studies subsequently performed confirmed the clinical assessment of each patient's course, and neither patient died of recurrent embolism.

Transvenous catheter pulmonary embolectomy.

Acute cardiovascular collapse in the hospitalized patient is associated with a high mortality rate and remains a therapeutic dilemma. Survival could be improved in the subgroup of patients with massive pulmonary thromboembolism if prompt surgical intervention is undertaken. This report presents the cases of two patients with cardiovascular collapse who survived transvenous catheter pulmonary embolectomy (herein described in detail). This procedure can be performed in any hospital with angiographic facilities and personnel trained in the technique. In our opinion it is the procedure of choice in patients with refractory cardiovascular collapse from massive pulmonary thromboembolism.

Complications encountered with the use of the Greenfield filter.

The Greenfield filter can be used with a low complication rate provided one adheres to certain principles. First, preoperative venography to define the inferior vena caval anatomy will help avoid difficulties associated with anatomic variations. At the time the study is carried out, it would be extremely useful if the radiologist places a radiopaque marker at the level of the renal veins. This will ensure that filters will be placed in the infrarenal position when appropriate, thus preventing occasional inadvertent discharge, particularly into the right renal vein. Second, use of a guide wire greatly facilitates passage of the introducer and accurate intracaval positioning. Third, intraoperative technical errors must be recognized and promptly corrected. Finally, meticulous postoperative follow-up is essential, and recurrent embolism or any change in filter position requires repeat roentgenography of the vena cava to guide appropriate corrective treatment.