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C Troppmann

Publications and source records attributed to C Troppmann.

At least 37 records · Page 2Linked to original sources
PubMed1996

Long-term peritoneal dialysis before transplantation and intra-abdominal infection after simultaneous pancreas-kidney transplantations.

OBJECTIVE: To investigate whether long-term peritoneal dialysis before transplantation entails a higher risk than hemodialysis for intra-abdominal infection after bladder-drained simultaneous pancreas-kidney transplantations. DESIGN: Large single-center case-control study. SETTING: A large university hospital (referral center). PATIENTS: In all, 189 bladder-drained simultaneous pancreas-kidney transplantations were done from January 1, 1986, to December 31, 1994: before transplantations were performed, 32 recipients (17%) were undergoing peritoneal dialysis, 71 recipients (38%) were undergoing hemodialysis, and 86 recipients (46) were not undergoing dialysis. MAIN OUTCOME MEASURES: The intra-abdominal infection rate after transplantation and the rate of graft loss due to infection. RESULTS: Intra-abdominal infections developed in 33 recipients (18%) after transplantation. Graft and patient survival rates were significantly lower for recipients with vs without an infection (P < .001 for both). Both the dialysis mode and dialysis dependence did not affect the infection rate: of the 33 recipients with an infection, 7 (21%) were undergoing peritoneal dialysis, 15 (46%) were undergoing hemodialysis, and 11 (33%) were not undergoing dialysis before transplantation (P = .3). The rate of graft loss due to infection was not significantly different for recipients who were undergoing peritoneal dialysis vs hemodialysis (P = .1). However, it was higher for recipients who were undergoing dialysis (peritoneal dialysis and hemodialysis) vs those patients who were not undergoing dialysis (P = .04). CONCLUSIONS: Candidates for simultaneous pancreas-kidney transplantation should undergo the transplantation preemptively (ie, before they become dependent on dialysis) because the rate of graft loss due to infection was higher for recipients who were undergoing dialysis (irrespective of the dialysis mode). If dialysis cannot be avoided, the choice of peritoneal dialysis vs hemodialysis can be individualized, since these dialysis modes do not have significantly different rates of infection or of graft loss due to infection.

Adult↗
PubMed1996

Pancreas graft loss caused by intra-abdominal infection. A risk factor for a subsequent pancreas retransplantation.

OBJECTIVE: To investigate whether previous pancreas graft loss caused by intra-abdominal infection is a risk factor for a subsequent pancreas retransplantation. DESIGN: Retrospective case-series analysis. SETTING: Large university hospital. PATIENTS: Of 97 pancreatic retransplantations (July 1, 1985 to June 30, 1994), 13 (13%) were performed after previous pancreas grafts had been lost because of intra-abdominal infection. MAIN OUTCOME MEASURES: Cause of retransplant graft loss; patient survival. RESULTS: Of 13 cases of pancreatic retransplantations performed after previous grafts had been lost because of intra-abdominal infection, 12 (92%) were again complicated by intra-abdominal infection. Of these 12 retransplantation infections, 10 were caused by the same microbial species that had caused failure of the previous graft 1 to 5 years earlier (8 required graft pancreatectomy [mortality rate, 25%], and 2 were successfully treated) and 2 were caused by different microbial species (both required graft pancreatectomy [mortality rate, 0%]). In 1 of the 13 retransplantations, prophylactic antimicrobial treatment was directed at the microbial species that had caused failure of the previous graft; no recurrent intra-abdominal infection developed. CONCLUSIONS: Intra-abdominal infection after a previous pancreas transplantation is a risk factor for recurrence of infection by the same microbial species after a subsequent retransplantation. For the selected patients who are considered for retransplantation in spite of their previous graft loss caused by intra-abdominal infection, periretransplantation antimicrobial prophylaxis should include a prolonged course of an agent directed against the previously identified microbial species.

Abdomen↗
PubMed1996

Use of FK 506 in pancreas transplantation.

Until recently, FK 506 was used only for rescue therapy after pancreas transplantation. We report our initial experience with FK 506 for 67 pancreas recipients (treated between 1 May 1993 and 30 April 1995). Of these recipients, 49 (73%) received FK 506 for induction and maintenance therapy, 12 (18%) for rescue or antirejection therapy, and 6 (9%) for reasons other than rescue or antirejection therapy. In our induction and maintenance therapy group, 32 recipients (65%) underwent a simultaneous pancreas-kidney transplant (SPK), 8 (16%) a pancreas transplant alone (PTA), and 9 (19%) a pancreas after previous kidney transplant (PAK). Quadruple immunosuppression was used for induction; the median FK 506 starting dose was 4 mg/day p.o. and target levels were 10-20 ng/ml. The most common side effects were nephrotoxicity (16%) and neurotoxicity (14%); transient episodes of hyperglycemia were also noted (12%), in particular in the presence of concurrent rejection and infection episodes. A matched-pair analysis was done to compare graft outcome with FK 506 versus cyclosporin A (CsA). For SPK recipients, pancreas graft survival at 6 months was 79% with FK 506 versus 65% with CsA (P = 0.04), for PTA, 100% versus 63% (P > 0.35), and for PAK, 88% versus 33% (P > 0.01). Pancreas graft loss due to rejection at 6 months posttransplant was lower with FK 506 versus CsA. Two FK 506 recipients died from B-cell lymphomas (Epstein-Barr virus positive) at 6 and 7 months posttransplant. In our rescue or anti-rejection group, 5 recipients underwent SPK, 3 PTA, and 4 PAK. The mean average FK 506 dose was 10 mg/day p.o. and the mean average FK 506 blood level was 11 ng/ml. The most common side effects were nephrotoxicity (33%) and neurotoxicity (16%). Two recipients developed hyperglycemic episodes, of whom 1 has remained on insulin with good exocrine pancreas graft function. Graft survival at 6 months after conversion was 75% for SPK, 67% for PTA, and 50% for PAK. Only one graft was lost due to chronic rejection. Our single-center experience shows that FK 506 after pancreas transplantation is associated with: (1) a low rate of graft loss due to rejection when used for induction, in particular for solitary pancreas transplants, (2) a high rate of graft salvage when used for rescue, (3) a 1% rate of new-onset insulin-dependent diabetes mellitus, and (4) a 3% rate of posttransplant lymphoma. Further studies are necessary to analyze the long-term impact of FK 506 on pancreas transplant outcome.

Adult↗
PubMed1996

Colon vs small bowel rejection after total bowel transplantation in a pig model.

With the advent of FK 506, small bowel transplantation has become clinically feasible. Both clinically and experimentally, jejunal and ileal biopsies are used for early diagnosis of rejection. More recently, the colon, in addition to the small bowel, has been transplanted to decrease the high incidence of diarrhea after small bowel transplantation. A Bishop-Koop ileostomy allows biopsies on a regular basis, but the diagnosis of rejection remains a problem after takedown of the ileostomy. Rejection of the ileum is more frequent and more severe than rejection of the jejunum or the colon. Colon biopsy after ileostomy takedown would not rule out rejection of the ileum.

Animals↗
PubMed1996

Combined liver and kidney transplantation.

Patients with end-stage renal and hepatic failure may be treated with combined liver and kidney transplantation (CLKTx). We reviewed the indications and outcomes of 16 CLKTx performed at the University of Minnesota between 1980 and 1994. The majority of the recipients (87.5%) were young patients affected by congenital hepatic anomalies and concomitant end-stage renal failure. Fourteen were treated with cyclosporin-based immunosuppression and had an excellent outcome: with an average of 6 years of follow-up, patient survival was 85.7%, liver graft survival 85.7%, and kidney graft survival 72%. The incidence of rejection episodes was similar to the rate of rejection in our solitary kidney and liver transplants. In conclusion, our experience supports the value of CLKTx in treating patients with simultaneous failure of both organs or with congenital enzymatic hepatic deficits leading to renal failure.

Adolescent↗
PubMed1996

Vascular graft thrombosis after pancreatic transplantation: univariate and multivariate operative and nonoperative risk factor analysis.

BACKGROUND: Vascular thrombosis is still the leading cause of nonimmunologic, technical pancreatic transplant graft failures. The paucity of published data--coupled with our large institutional experience with pancreatic transplantation in all recipient and transplant categories, using a wide spectrum of surgical techniques--provided the impetus for a retrospective study of graft thrombosis risk factors. STUDY DESIGN: Four hundred thirty-eight patients with pancreatic transplants (45 percent simultaneous pancreas-kidney [SPK], 23 percent pancreas-after-kidney [PAK], and 32 percent pancreatic transplants alone [PTA] and with Type I insulin-dependent diabetes mellitus were studied retrospectively. Of 438 pancreatic transplants, 90 percent were bladder-drained and 10 percent were enteric-drained. Ninety-three percent were from cadaver donors, 90 percent were whole-organ grafts, and 20 percent were retransplantations. Quadruple immunosuppression was given. For bladder-drained, whole-organ transplantations (n=378), we performed Cox regression analyses to study the impact on pancreatic graft thrombosis of donor, recipient, mode of preservation, and surgical variables. RESULTS: The overall thrombosis rate was 12 percent (5 percent arterial, 7 percent venous). For cadaver, bladder-drained, whole-organ pancreatic transplants, the thrombosis incidence was highest in PAK recipients (20 percent). The PAK category was also found to be an independent risk factor for thrombosis by stepwise Cox regression analysis. In separate stepwise Cox regression analyses for each category, other identified risk factors for thrombosis included the following: donor age (PAK, PTA); cardiocerebrovascular cause of donor death (SPK, PAK); the use of an aortic Carrel patch (SPK); arterial pancreatic graft reconstruction using a splenic artery to superior mesenteric artery anastomosis (SPK, PTA) or an interposition graft between the splenic artery and the superior mesenteric artery (PTA); portal vein extension graft (PAK); left-sided implantation into the recipient (PAK); and graft pancreatitis (defined as hyperamylasemia exceeding five days post-transplant [PAK, PTA]). CONCLUSIONS: Older donors or those who died of cardiocerebrovascular disease should not be considered for any recipient category. Preservation time needs to be minimized and strategies need to be developed to decrease graft pancreatitis. Surgically, left-sided implantation and arterial reconstructions other than the Y-graft also increase risk, as do portal vein extensions. Renal transplants alone in prospective PAK recipients with Type I diabetes mellitus should, therefore, always be implanted left-sided to allow for right-sided pancreatic graft placement.

Adult↗
PubMed1996

Intra-abdominal fungal infections after pancreatic transplantation: incidence, treatment, and outcome.

BACKGROUND: Intra-abdominal infections account for 15 percent of technical failures after pancreatic transplantation. Although some data are available about intra-abdominal bacterial infections, no study has analyzed the incidence, treatment, and outcome of intra-abdominal fungal infections. STUDY DESIGN: We retrospectively studied 445 consecutive pancreatic transplantations--45 percent were simultaneous pancreatic and renal, 24 percent pancreatic after renal, and 31 percent pancreatic transplantations alone--in patients with Type I diabetes mellitus. Donors were cadavers in 92 percent and living relatives in 8 percent. Primary transplantations were done in 80 percent and retransplantation in 20 percent. Of these 445 pancreatic transplantations, 90 percent were bladder-drained, 9 percent enteric-drained, and 1 percent duct-injected. Only symptomatic patients with documented culture-positive intra-abdominal fungal infections were included. RESULTS: Intra-abdominal fungal infections occurred after pancreatic transplantation in 41 (9.2 percent) of 445 patients. Donor age, but not recipient age, was a significant risk factor. The rate of infections was higher for enteric-drained (21 percent) than for bladder-drained (10 percent) transplantations; for organs donated by living relatives (16 percent) than for those from cadavers (9 percent); and for pancreatic after renal (12 percent) and simultaneous pancreatic-renal (11 percent) than for pancreatic-only (5 percent) recipients. The rate of intra-abdominal fungal infections was 6 percent for recipients who were given antifungal prophylaxis (fluconazole, 400 mg/day for seven days after transplantation) compared with 10 percent for those without prophylaxis. The one-year graft survival rate for recipients with infection was 17 percent compared with 65 percent for those without (p = 0.0001); the survival rate was 70 percent compared with 92 percent for patients with and without infection, respectively (p = 0.0007). In 22 percent of recipients, the infection resolved and graft function persisted; in 58 percent, the infection resolved after transplant pancreatectomy; and in 20 percent, death occurred despite transplant pancreatectomy. Recipients with sole fungal or fungal and bacterial infection (n = 41) were 50 percent less likely to recover with a functioning graft and had a risk of death that was three times higher (p < or = 0.05) than those with sole bacterial infection (n = 48). CONCLUSIONS: Intra-abdominal fungal infections after pancreatic transplants are associated with high morbidity and mortality rates, significantly higher than for sole bacterial infections. In addition to aggressive treatment, including transplant pancreatectomy and reduction of immunosuppression, efforts must be made toward better prevention of intra-abdominal fungal infections.

Adult↗
PubMed1995

Cystoscopic biopsies in pancreaticoduodenal transplantation. Are duodenal biopsies indicative of pancreas dysfunction?

Tissue diagnosis of pancreas graft dysfunction is desirable. Bladder-drained pancreaticoduodenal transplants allow tissue diagnosis by cytoscopic biopsy procedures of the pancreas and duodenum. To assess the diagnostic utility of duodenal biopsies, we reviewed all cystoscopically obtained pancreas and duodenal biopsy tissues at our institution (July 1, 1989 through September 30, 1993). Adequate tissue for histologic examination was obtained from 75 biopsies in 58 recipients. Indications for cytoscopic biopsies were relative hypoamylasuria in 85%, hematuria in 6%, hyperamylasemia in 3%, and other causes in 6%. Duodenal specimens were available from 52 biopsies (25 with, and 27 without, concurrent pancreas biopsies). Of the 27 duodenal biopsies alone, 3 were diagnostic of rejection, 15 had features consistent with rejection, 6 were normal, 1 showed fibrosis, 1 showed necrosis, and 1 was ulcerated. Thus, two-thirds of the duodenal biopsies alone yielded clinically relevant information resulting in antirejection treatment. In 25 of the duodenal biopsies, pancreas tissue was also available (11 simultaneous pancreas-kidney, 9 pancreas transplant alone, and 5 pancreas after kidney recipients). Findings in both organs completely agreed in 9 (36%) of the biopsies. In 7 (28%), rejection was suggested or diagnosed in both organs, although the organs were discrepant with regard to the presence of vascular rejection (6 pancreas, 1 duodenum). In 2 (11%), minor nonrejection discrepant findings were present. Therefore, in 18 of 25 (72%) pancreas-duodenal biopsies, treatment would not have been different if only one graft had been biopsied. But in the other 7 (28%), treatment would have been different if only the organ with negative findings had been biopsied. In 6 cases (4 duodenal, 2 pancreas), rejection was seen in one organ but not the other. In 1 case, cytomegalovirus (CMV) inclusions were present in the duodenum, but the pancreas was normal. We conclude that (1) the duodenum and pancreas can reject independently of each other, and a negative biopsy does not preclude rejection of the other organ; (2) duodenal biopsies determined therapeutic decisions one-fifth of the time when both tissues were available for examination, and two-thirds of the time when only duodenal tissue was available; and (3) since cystoscopy allows easy access to the duodenum, both the pancreas and duodenum should be biopsied whenever possible; tissue samples of one organ alone are sufficient only with positive findings.

Adult↗
PubMed1995

Delayed graft function, acute rejection, and outcome after cadaver renal transplantation. The multivariate analysis.

The impact of delayed graft function on outcome after cadaver renal transplantation has been controversial, but most authors fail to control their analyses for the presence or absence of rejection. We studied 457 adult recipients of primary cadaver allografts at a single institution during the cyclosporine era. All patients received sequential immunosuppression. The incidence of delayed graft function (defined as dialysis being required during the first week after transplant) was 23%. There was a significant association between delayed graft function and cold ischemia time > 24 hr (P = 0.0001) and between delayed graft function and the occurrence of at least one biopsy-proven rejection episode (P = 0.004). Actuarial graft survival was not significantly different when comparing delayed graft function versus no delayed graft function for patients without rejection (P = 0.02). However, it was significantly worse for patients with both delayed graft function and rejection versus those with delayed graft function but no rejection (P = 0.005), as well as for grafts preserved > 24 hr versus < or = 24 hr (P = 0.007). By multivariate analysis, delayed graft function per se was not a significant risk factor for decreased graft survival for patients without rejection (P = 0.42). In contrast, rejection significantly decreased graft survival for grafts with immediate function (relative risk = 2.3, P = 0.0002), particularly in combination with delayed graft function (relative risk = 4.2, P < 0.0001). While cold ischemia time > 24 hr was also a significant risk factor (relative risk = 1.9, P = 0.02), other variables (preservation mode, 0 HLA Ag mismatch, age at transplantation, gender, diabetic status, and panel-reactive antibody at transplantation) had no impact on graft survival. Patient survival was significantly affected by the combination of delayed graft function and rejection (relative risk = 3.1, P < 0.0001), age at transplantation > 50 years (relative risk = 2.6, P < 0.0001), and diabetes (relative risk = 1.8, P = 0.006). Further studies are necessary to elucidate the mechanisms linking delayed graft function and rejection, which, in combination, lead to poor allograft outcome.

Adult↗
PubMed1995

Retransplantation after renal allograft loss due to noncompliance. Indications, outcome, and ethical concerns.

Noncompliance is increasingly recognized as a major cause of renal allograft loss, but the results of retransplantation of such patients have never been described. At our center, 52 of 3525 kidney recipients between June 1, 1963 and December 31, 1993 lost their graft due to overt noncompliance. Of these, 14 (27%) underwent retransplantation after thorough interdisciplinary evaluation. All but 1 patient had returned to dialysis before retransplantation. Of the retransplanted grafts, 2 were lost (1 technical failure, 1 chronic rejection in a compliant patient); both recipients were retransplanted once again. Currently, all retransplanted patients are alive and have a functioning graft. We conclude that for selected patients with graft loss due to noncompliance excellent results can be achieved with retransplantation. However, the issue of retransplanting previously noncompliant patients in the face of a significant donor organ shortage requires public debate.

Adolescent↗
PubMed1995

Correlation between cystoscopic biopsy results and hypoamylasuria in bladder-drained pancreas transplants.

BACKGROUND: Urinary amylase (UA) remains the most common biochemical parameter to detect rejection in bladder-drained pancreas allografts. With the development of the cystoscopic transduodenal pancreas transplant biopsy technique, tissue samples of the pancreas graft are now frequently obtained. A definitive correlative analysis between UA activity and biopsy results has not been done in the three different pancreas transplant categories (simultaneous pancreas-kidney, pancreas transplant alone, and pancreas after kidney). METHODS: We studied 66 pancreaticoduodenal biopsy specimens obtained for hypoamylasuria. Rejection was defined as a greater than 25% decrease from stable posttransplantation baseline on two consecutive measurements at least 12 hours apart. To perform biopsies we used our newly developed 14- and 16-gauge core-cut needles (50 cm long). Biopsy specimens were considered positive if either pancreatic or duodenal rejection was found. To assess the quality of UA activity we studied 13 biopsy specimens from patients with stable UA levels; these 13 specimens were negative for rejection. RESULTS: Acute rejection was diagnosed in 36 biopsy specimens (55%). The mean decrease in UA levels was 67% +/- 8% (range, 28% to 99%) for the positive biopsy results, and 57% +/- 16% (range, 22% to 92%) for the negative biopsy results (p = 0.147). Within 1 month, UA levels returned to baseline in 19% of our patients with positive biopsy results versus 97% with negative results; postbiopsy 1-year graft survival was 64% versus 97% (p < or = 0.05). In assessing the test quality of our biopsy specimens (including 13 obtained for reasons other than hypoamylasuria), we found a sensitivity of 100% (stable UA levels mean no rejection) and a specificity of 30%. The predictive value of a positive test was 53%; of a negative test it was 100%. By performing biopsies we avoided antirejection treatment in 47% of the patients studied. We found no biopsy-related complications. CONCLUSIONS: Stable UA levels reliably rule out rejection; a decrease is a marker for acute rejection but is unspecific. Performing biopsy is currently the only way to reliably diagnose rejection in solitary pancreas recipients (pancreas transplant alone and pancreas after kidney) and in simultaneous pancreas-kidney recipients with isolated hypoamylasuria. The procedure is safe and should always be attempted to avoid unnecessary rejection treatment.

Adult↗
PubMed1995

Short- and long-term outcomes of kidney transplants with multiple renal arteries.

OBJECTIVE: The authors determined whether the use of kidney allografts with multiple renal arteries adversely effects post-transplant graft and patient outcome or increases the incidence of vascular and urologic complications. BACKGROUND: Kidney grafts with multiple renal arteries have been associated with an increased incidence of early vascular and urologic complications. Kidney transplants with single versus multiple renal arteries have not been compared in regard to long-term graft and patient outcome or post-transplant incidence of hypertension, acute tubular necrosis, rejection, and late vascular and urologic complications. METHODS: We analyzed 998 adult kidney transplants done from December 1, 1985 through June 30, 1993, in which only the recipient's external or internal iliac artery was used for anastomosis. We divided the study population into 3 groups: Group A-1 renal artery, 1 arterial anastomosis (n = 835), Group B-->1 renal artery, 1 arterial anastomosis (n = 112), Group C-->1 renal artery, > 1 arterial anastomosis (n = 51). We compared the incidence of post-transplant hypertension, acute tubular necrosis, acute rejection, and vascular and urologic complications; mean creatinine levels at 1, 3, and 5 years post-transplant; and patient and graft survival. Univariate and multivariate analyses were done to identify risk factors for vascular complications. RESULTS: We found no significant differences among the three groups for the following variables: post-transplant hypertension, acute tubular necrosis, acute rejection, creatinine levels, early vascular and urologic complications, and graft and patient survival. In kidneys with single arteries, the presence (vs. absence) of an aortic patch and the type of the arterial anastomosis (end-to-end to the hypogastric vs. end-to-side to the external iliac artery) did not have an impact on the incidence of early or late vascular complications. In kidneys with multiple arteries, only the rate of late renal artery stenosis was higher, the rate of early vascular and urologic complications was not different. Our multivariate analysis identified acute tubular necrosis as a risk factor for renal artery and vein thrombosis; graft placement on the left side for arterial thrombosis; and preservation time > or = 24 hours and multiple renal arteries for renal artery stenosis. CONCLUSIONS: Results of kidney transplants using allografts with multiple versus single arteries are similar.

Adolescent↗