Biomedical subjects
Publications and source records attributed to J Pirenne.
Congenital absence of useful ilio-caval venous segment is a very infrequent congenital anomaly and makes unfit grafting of a kidney transplant in iliac fossa. We report the case of a 18 years old male affected by this abnormality who was transplanted in intraabdominal situation. We review technical alternatives offered by the literature.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Rejection remains a major barrier to successful bowel transplantation, and immunosuppressive protocols are far from standardized. In 88 nonrelated outbred pigs, we compared the effects of two immunosuppressive regimens--one with FK506, the other with cyclosporine (CsA) and pig antithymocyte globulin (ATG)--on incidence and severity of rejection in the early, critical posttransplant period. Group A (n = 14) was nonimmunosuppressed (controls). Group B (n = 17) received pig ATG (10 mg/kg/day x 10 days), CsA (3 mg/kg/day), prednisolone (2 mg/kg/day), and azathioprine (2.5 mg/kg/day); prednisolone and azathioprine were each reduced by 50% at 8 and 15 days posttransplant. Trough CsA whole-blood concentrations were > or = 400 ng/ml for the first 7 days, > or = 200 ng/ml thereafter. Group C (n = 13) received FK506 (0.2 mg/kg/day) and prednisolone (2 mg/kg/day); prednisolone was reduced by 50% at 8 and 15 days. FK506 whole-blood concentrations were > or = 20 ng/ml. All immunosuppression in groups B and C was given intravenously. We performed orthotopic small bowel transplants with systemic venous drainage. Recipient bowel was resected distal to the second portion of the duodenum and proximal to the rectum at transplant; bowel continuity was restored by duodenojejunostomy; ileostomy was created distally to allow access for daily biopsies. We graded interstitial and vascular rejection separately, according to a scoring system (no, mild, moderate, and severe rejection). Rejection-free graft survivals at 7, 14, and 21 days posttransplant were 38%, 19%, and 0% in group A; 93%, 93%, and 62% in group B; and 100%, 91%, and 82% in group C (P < 0.001). Comparing rejection in the immunosuppressed groups, group C (FK506) had a stronger tendency toward rejection than group B (CsA-ATG); significant differences between groups B and C were, however, noted only on individual days posttransplant, not over time. The death rate due to irreversible rejection was not significantly different in groups B and C (P = 0.8), but was significantly better in both of these immunosuppressed groups than in group A (P < 0.001). Pig survival was significantly longer in group C than in B (P = 0.001) due to a lower infection rate in group C. Posttransplant serum interleukin 2 and 7 levels did not correlate with rejection grades. Graft-versus-host reaction was noted only in the skin in 29% of group A, 73% of group B, and 77% of group C pigs; liver and native bowel were not involved.(ABSTRACT TRUNCATED AT 400 WORDS)
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.
OBJECTIVE: To assess the effects of abdominal operations on the production of cytokines as one of the mechanisms of postoperative immunosuppression. DESIGN: Prospective study. SETTING: University hospital, Belgium. SUBJECTS: 19 Selected patients who underwent operations for benign (n = 10) or malignant (n = 9) diseases. INTERVENTIONS: Whole blood was collected in heparinised tubes before operation and on postoperative days 1, 2, 3, 5, 7, and 9. After 1/10 dilution in culture medium the whole blood cells were stimulated with 5 micrograms/ml phytohaemagglutinin and 25 micrograms/ml lipopolysaccharide, and incubated at 37 degrees C in 5% carbon dioxide. Concentrations of interleukin 1 (IL-1), tumour necrosis factor alpha (TNF alpha), and interleukin 6 (IL-6) were measured at 24 hours, and interferon-gamma and interleukin 2 (IL-2) were measured at 72 hours, with commercially available assays. OUTCOME MEASURES: Production of the monokines IL-1, TNF alpha, and IL-6, and of the lymphokines IL-2 and interferon-gamma, postoperatively. The monokines were expressed as a percentage of the preoperative values/monocyte, and the lymphokines as a percentage of preoperative values/lymphocyte. RESULTS: Production of IL-1 and TNF alpha, but not IL-6, decreased immediately after operation then returned to preoperative values. Production of IL-2 and interferon-gamma were significantly reduced immediately after operation, and that of interferon-gamma was still depressed on the ninth postoperative day. CONCLUSION: Cytokine production is altered after abdominal operations. The production of interferon-gamma may be a more sensitive indicator of altered immune response and vulnerability to infections and tumour growth than concentrations of other cytokines.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Cytokines regulate both aspecific inflammatory responses and specific immune responses. Inflammatory changes occur in the organ transplant as a result of tissue trauma and ischemia/reperfusion in the organ donor and at the time of transplant operation. There is a possibility that cytokines play a role in mediating theses changes. These aspecific inflammatory changes may not only affect graft function but also influence graft immunogenicity (enhanced MHC and adhesion molecule expression) and thus, vulnerability to rejection. Cytokines orchestrate the specific immune response elicited by organ transplantation. Relevance of cytokines to the rejection reaction is multifactorial in nature: 1) promotion of the proliferation an differentiation of specific alloreactive T and B cells clones and differentiation and activation of CTL and NK cells, 2) chemotactic effect and induction of the expression of adhesion molecules, 3) enhancement of MHC class I and II expression, and 4) direct cytotoxic effect on the target grafted cells. Therefore, modulation of cytokine activity either specifically (monoclonal antibody, soluble receptor, etc.) or aspecifically (cyclosporin, FK 506, Rapamycin, steroids, etc.) is essential in controlling graft rejection. Determination of circulating cytokines and cytokines measurement within the biological fluids produced by an organ transplant may help in the diagnosis of rejection episodes and other complications following organ transplantation.
We reviewed urologic complications of 1183 consecutive primary or secondary renal transplants performed with bladder anastomoses at the University of Minnesota Hospital between 1985 and 1993. The Politano-Leadbetter (PL) technique of ureteroneocystostomy was used in 410 patients; the multistich (MS) extravesical technique modified from the methods of Witzel, Sampson, and Lich in 295; and the extravesical single-stitch (SS) technique in 478. Urologic complications occurred in 81 patients (6.8%). Of these complications, 68 (5.7%) were early (< 4 months) and 13 (1.1%) late; 32 (7.8%) were after PL, 17 (5.8%) after MS, and 32 (6.7%) after SS. A total of 13 patients had an anastomotic leak, 7 (1.7%) after PL, 4 (1.4%) after MS, and 2 (0.0004%) after SS; 49 patients had a ureterovesical obstruction, 16 (4.0%) after PL, 12 (4.0%) after MS, and 21 (4.2%) after SS; 5 patients had a ureteropelvic obstruction, 2 (0.5%) after PL, 2 (0.7%) after MS, and 1 (0.2%) after SS; and 14 patients had hematuria, 7 (1.7%) after PL, 1 (0.34%) after MS, and 6 (1.3%) after SS. Of the 81 patients with urologic complications, one (1%) resolved spontaneously; 30 (37%) were treated with temporary percutaneous nephrostomy, 17 (21%) with dilatation and stent; the 14 (17.3%) with hematuria were treated via cystoscopy; 19 (23%) required reoperation. Only 2 (2.5%) patients lost their graft. For both cadaver and living donor recipients, there was no difference between techniques for early and late complications of leakage, stricture, and hematuria. Each technique has certain advantages and each should be in every surgeon's repertoire.
Explore the source record for details and available documents.
Multiple organ procurement techniques are increasingly popular in many transplant centers. This paper describes a technique for multiorgan unit(s) explantation in rats. The procedure involves in situ preliminary dissection, cold perfusion of the thoracic and abdominal organ units as separate procedures, explantation, and finally the ex situ isolation of various organ units as single and/or multiple organ combination units. The procedure is feasible, allows for flexibility in the separation of combination organ units, and is reproducible. The exercise is provided as a training and research tool for clinical and research transplant surgeons. The technique is also presented as an animal model for clinical organ sharing.
The small bowel (SB), an organ replete with lymphocytes, may provoke graft-versus-host disease (GVHD) after transplantation (Tx). Since tumor necrosis factor (TNF) has been suspected of mediating the tissue lesions of GVHD, we sought to determine whether TNF could be detected in the serum of rats undergoing GVHD after SBTx or lymphocyte transfer. For this purpose, postoperative serum TNF activity was determined in Lewis x Brown Norway (LBNF1) hybrid rats suffering from GVHD after undergoing transplantation of an entire (group 1; n = 8) or a segmental (group 2; n = 4) Lew SB, or after i.p. injection with lethal doses (500 x 10(6)) of Lew lymphocytes (group 3; n = 3). Control LBNF1 received i.p. small doses (50 x 10(6)) of Lew lymphocytes (group 4; n = 4). Serum TNF activity was assessed using the WEHI bioassay. In rats with acute and lethal GVHD after entire SBTx (group 1) or injection with large doses of lymphocytes (group 3), TNF activity gradually increased and reached high levels by the time the rats were agonal. In segmental SBTx rats (group 2), GVHD was less severe than in entire SBTx rats. Similarly, the increase in TNF activity was less intense and only transient since it had returned to control levels by the time the rats had completely recovered from GVHD. In control rats primed with small doses of lymphocytes (group 4), GVHD did not occur and no increase in TNF activity was detected.(ABSTRACT TRUNCATED AT 250 WORDS)
The case reports of three patients who received cancer-bearing organs at this institution are presented. A fourth recipient, who was to be transplanted with a cancerous kidney, was spared this disastrous complication. The relevant data regarding the donors is also alluded to, with special reference to the type and site of the primary malignancy. Following these case reports, the implications of these issues, their possible prevention, and further management are discussed.