Klatskin tumors and Klatskin mimicking lesions of the biliary tree

AIM

We report on the preoperative capability of imaging modalities and clinical assessment to differentiate between Klatskin tumors and Klatskin mimicking lesions of the biliary tree. Adenocarcinomas of the hepatic ducts (Klatskin tumors) mimic benign fibrosing cholangitis. Extensive resections carry a substantial risk but offer the only chance for cure in patients with a Klatskin tumor.

METHODS

Thirty-three consecutive patients who underwent resection for suspicion of a malignant tumor of the hepatic hilum were reviewed. All patients underwent preoperative ultrasonography, computed tomography, ERCP and angiography. The patients were divided into a group of true Klatskin tumors and a group of benign Klatskin mimicking lesions.

RESULTS

Twenty-seven of the resected specimens were malignant tumors, and six lesions showed only fibrosing cholangitis. Preoperative clinical presentation and imaging modalities were very similar between Klatskin tumors and fibrosing cholangitis.

CONCLUSIONS

Management of obstruction of the liver hilum is dictated by the suspicion of malignancy. Complete removal of the tumor remains the therapeutic aim but clinical presentation and imaging modalities cannot help to differentiate between Klatskin tumors and Klatskin mimicking lesions prior to surgery.

Is there still a need for living-related liver transplantation in children?

OBJECTIVE

To assess and compare the value of split-liver transplantation (SLT) and living-related liver transplantation (LRT).

SUMMARY BACKGROUND DATA

The concept of SLT results from the development of reduced-size transplantation. A further development of SLT, the in situ split technique, is derived from LRT, which itself marks the optimized outcome in terms of postoperative graft function and survival. The combination of SLT and LRT has abolished deaths on the waiting list, thus raising the question whether living donor liver transplantation is still necessary.

METHODS

Outcomes and postoperative liver function of 43 primary LRT patients were compared with those of 49 primary SLT patients (14 ex situ, 35 in situ) with known graft weight performed between April 1996 and December 2000. Survival rates were analyzed using the Kaplan-Meier method.

RESULTS

After a median follow-up of 35 months, actual patient survival rates were 82% in the SLT group and 88% in the LRT group. Actual graft survival rates were 76% and 81%, respectively. The incidence of primary nonfunction was 12% in the SLT group and 2.3% in the LRT group. Liver function parameters (prothrombin time, factor V, bilirubin clearance) and surgical complication rates did not differ significantly. In the SLT group, mean cold ischemic time was longer than in the LRT group. Serum values of alanine aminotransferase during the first postoperative week were significantly higher in the SLT group. In the LRT group, there were more grafts with signs of fatty degeneration than in the SLT group.

CONCLUSIONS

The short- and long-term outcomes after LRT and SLT did not differ significantly. To avoid the risk for the donor in LRT, SLT represents the first-line therapy in pediatric liver transplantation in countries where cadaveric organs are available. LRT provides a solution for urgent cases in which a cadaveric graft cannot be found in time or if the choice of the optimal time point for transplantation is vital.

Expression of 17-1A antigen and complement resistance factors CD55 and CD59 on liver metastasis in colorectal cancer

Despite radical surgery, the prognosis for colorectal cancer patients with liver metastases has not changed markedly. Furthermore, no standard adjuvant therapeutic regimen has been developed. Adjuvant therapy with monoclonal antibodies (e.g., against 17-1A), which has been shown to be effective in preventing metastatic relapse in patients with Dukes' C colorectal cancer, might be a promising approach for these patients. However, the cytotoxic effects of monoclonal antibodies can be blocked by coexpression of complement resistance factors that inhibit antibody-dependent complement-mediated cytotoxicity. We therefore analyzed immunohistochemically the expression of 17-1A and the membrane-bound complement resistance factors CD55 and CD59 on metastatic tumor cells in the livers of 71 patients with colorectal carcinoma who had undergone resection of their metastases with curative intent. In 67 (94%) of 71 patients, liver metastases with homogeneous expression of 17-1A was seen. Heterogeneous expression of 17-1A was seen in four patients (6%). Heterogeneous expression of CD55 or CD59 was observed in 8 (11%) of 71 patients and 4 (6%) of 71 patients, respectively. None of the patients showed homogeneous expression of either CD55 or CD59. All patients with CD55 or CD59 expression showed homogeneous 17-1A expression, whereas none of the four patients with heterogeneous 17-1A expression was positive for CD55 or CD59. Our data indicate that 17-1A is widely expressed on liver metastases of patients with colorectal carcinoma. Therefore patients with completely resected liver metastases might be suitable candidates for adjuvant therapy with and-17-1A antibody since only a few of these lesions showed coexpression of complement resistance factors.

In vitro function of islets of Langerhans encapsulated with a membrane of porcine chondrocytes for immunoisolation

BACKGROUND/AIMS

Widespread clinical application of islet transplantation remains restricted, because of insufficient methods to prevent rejection and autoimmune destruction of islet grafts. In this study we demonstrate long-term function of islets of Langerhans within a capsule of porcine chondrocytes which may serve as an immunoisolation barrier utilizing the immunoprivileged properties of the chondrocyte matrix.

METHODS

Islets of Langerhans were isolated from Lewis rats, seeded on biodegradable polyglycolic acid polymer, and encapsulated with a monolayer of porcine chondrocytes. The encapsulated constructs and controls were kept in culture for 5 weeks. One group was exposed to a glucose challenge every 5th day. The insulin concentration of the culture medium was measured. Histological and insulin-immunohistochemical studies were performed.

RESULTS

Hematoxylin and eosin histology demonstrated viability of the islets of Langerhans. The intact morphology was demonstrated by Heidenhain staining. Toluidine blue showed viability of surrounding chondrocyte layers. Immunohistochemistry was positive for insulin within the beta cells of the islets. Both encapsulated constructs and nonencapsulated controls showed increasing insulin levels after glucose challenge.

CONCLUSIONS

We can tissue engineer a chondrocyte encapsulation membrane which permits diffusion of glucose and insulin. Islets of Langerhans survive within the chondrocyte capsule, and the glucose/insulin feedback mechanism remains intact.

Hepatic involvement in hereditary hemorrhagic telangiectasia: an unusual indication for liver transplantation

Hereditary hemorrhagic telangiectasia (HHT) is a vascular disease with multiple organ manifestations. Severe hepatic involvement is an unusal indication for liver transplantation. We report on a 39-year-old woman diagnosed with HHT and decompensation of the disease during her second pregnancy. After delivery, hemobilia occurred, followed by severe therapy-resistant cholangitis and progressive liver dysfunction. Because of progressive loss of liver function, orthotopic liver transplantation needed to be performed. The various aspects of liver involvement in Osler's disease, diagnosis, and therapy are discussed.

Split-cava technique: liver splitting for two adult recipients

Split-liver transplantation for 2 adult recipients is a challenging procedure because of the need to split through the midplane of the donor liver. In applied techniques, usually the middle hepatic vein is retained with the left split and the vena cava retained with the right split graft, particularly to avoid serious venous congestion of the right graft after reperfusion. The indispensable division of the caudate lobe veins lead to uncertain viability of liver segment I, and resection might be necessary. To provide optimal venous drainage of both hemiliver grafts, we developed the split-cava technique. This article describes our new technique of liver splitting, which has been successfully used in 2 in situ harvesting procedures.

Split liver transplantation (SLT)

OBJECTIVES

In the last three decades liver transplantation (LT) has become a standard procedure for terminal liver failure. Anyway the procedure is highly limited by the availability of donor organs. The use of segmental liver grafts from living or cadaver donors are an attractive way to increase the donor pool for LT in adults and children.

METHODS

Between 1991 and April 1999 we performed 647 liver transplantations in 416 adults and 231 children. 431 OLT, 124 SLT and 92 LRLT. Commonly used segmental liver grafts are the full right graft, the full left graft, the left lateral lobe graft and the right extended graft from living or cadaver donors respectively.

RESULTS

The 1-year survival of elective SLT in adults is 80.5% and in children 84.3% (SLT + LRLT).

CONCLUSIONS

Splitting procedures in liver transplantation are a promising completion to whole organ transplantations. The results of split liver (SLT) and living related liver transplantations (LRLT) are comparable to whole organ transplantations. These methods are able to increase the organ pool and thus decrease the pretransplant mortality both in children and adults.

Mycophenolate mofetil for prevention of liver allograft rejection: initial results of a controlled clinical trial

Mycophenolate Mofetil (M MF) is a new immunosuppressive agent with proven efficacy for the prevention of kidney allograft rejection. However, only little experience is available with the use of MMF in liver transplant recipients.

OBJECTIVES

In this prospective, controlled trial the efficacy and safety of MMF and Azathioprine (AZA) were compared in a Neoral based quadruple immunosuppressive regimen after orthotopic liver transplantation.

METHODS

Between 12/96 and 12/98 57 adult patients were enrolled in the study at the University of Hamburg. 28 patients were randomised to MMF, 29 patients to AZA in combination with equivalent doses of lymphocyte antibodies, Neoral and methylprednisolone.

RESULTS

After a median follow-up of 10+/-3.2 months patient or graft survival did not differ significantly between the MMF and AZA group. However, MMF treated patients experienced less frequently acute rejection episodes (MMF: 6/28; 21.4% versus AZA: 13/29; 44.8%) (p=0.06). Furthermore, thrombocytopenia (MMF: 6/28; 21.4% versus AZA: 14/29; 48.3%) (p<0.05) and leukopenia (MMF: 2/28; 7.1% versus AZA: 6/29; 20%) (p=0.14) were less often observed under MMF compared to AZA. The incidence of serious bacterial infections and cytomegalovirus infections was almost identical in both groups. These preliminary data suggest that after liver transplantation primary immunosuppression with MMF is advantageous over AZA with regard to safety and efficacy.

[Colorectal liver metastases: does the number of metastases determine of resection is oncologically indicated?]

Complete surgical removal of colorectal liver metastases offers the patient the only curative option as long as there is no extrahepatic spread. Apparently the number of parameters of prognostic significance is unlimited. Consequently their importance for the individual prognosis remains questionable. One of the most frequently discussed parameters is the number of lesions in the liver. The aim of this study was therefore to review the literature and to analyze our own patients with colorectal liver metastases. For 302 patients a complete follow-up was available. The patients were grouped according to the number of lesions and the status of resection (R0, R1, R2, Exploration). The groups were compared by Kaplan Meier Analyses with log rank tests. The literature was reviewed until December 1998. The number of metastases was confirmed to be of prognostic value. Three or more metastases made a resection without residual tumor more unlikely than if there were only two or less (17.8% versus 67.2%). 5-year survival after curative resection was reduced in the group with more metastases from 36% to 9% and 10-year survival was reduced from 18% to 0% without reaching statistical significance (p < 0.07). The number of liver metastases may have some prognostic impact for patients after colorectal cancer. However, even if more than four metastases were resected with clear margins some patients did survive for a long time. The most important parameter to predict an oncological benefit is resection without residual tumor. If this is technically and functionally possible the patient should not be denied surgery, his only chance for cure.

[Hepatocellular carcinoma: surgical treatment]

Worldwide the hepatocellular carcinoma (HCC) is one of the most common malignancies. There is a coincidence with liver cirrhosis or chronic hepatitis B/C in most cases. HCC can be suspected by ultrasound and by rise of the tumor marker (AFP). Further investigations, like biopsies, are not necessary if angiography or computed tomography in combination with patient history and elevated AFP levels are positive. The prognosis of untreated HCC is extremely poor. Live expectancy of symptomatic patients is only a couple of weeks. Radical tumor removal by liver resection or transplantation is the only treatment with curative intent. However these options are only suitable for patients with limited disease. Five year survival after curative liver resection depends on the tumor stage, ranging from 25% to 67%. The results after liver transplantation are similar for small cancer. Large, symptomatic tumors are in most cases only suitable for palliative treatment (chemoembolisation, ethanol injection, chemotherapy, immunotherapy). The strong dependence of prognosis on tumor extent underlines the importance of screening patients with elevated risk of developing an HCC. The early recognition of small tumors allows curative therapy with good results.

[Preoperative hemodilution with bovine hemoglobin. Acute hemodynamic effects in liver surgery patients ]

Haemoglobin solutions can be an alternative to allogeneic red-cell transfusions because they combine colloid osmotic with oxygen transport properties. Since severe toxic side effects have been overcome by ultrapurification, clinical interest has been focused on haemodynamics changes during application of haemoglobin preparations. The present clinical study examines changes of haemodynamic and oxygen transport parameters during and after haemodilution with ultrapurified polymerized bovine haemoglobin (HBOC-201) in comparison to hydroxyethyl starch (HES).

METHODS

After approval of the Ethics Committee, 12 patients (6 males and 6 females, mean age 59 +/- 10 years, ASA 1-2) undergoing elective liver resection were randomly allocated to receive either 3 ml.kg-1 6% HES 70,000/0.5 (group 1) or 0.4 g.kg-1 HBOC-201 (group 2) within 30 min following autologous blood donation of 1 l and substitution with 2 l Ringer's lactate. Measurements of blood gases, haemodynamics, and oxygen transport parameters were performed after induction of general anaesthesia, prior to and after blood donation, during and after infusion, at the beginning of surgery, and in the intensive care unit.

RESULTS

Demographic characteristics did not differ between groups. In contrast to the HES group, mean arterial pressure increased by 18% over baseline measurements in group 2. While pulmonary vascular resistance showed a trend to higher values in group 2, systemic vascular resistance increased to a maximum of 42% over baseline in group 2 and was twice as high as in the HES group. The cardiac index was lower in the HBOC-201 group than in the HES group. During and after HBOC-201 infusion, mixed-venous oxygen saturation and content and calculated oxygen delivery were lower in group 2 in comparison to group 1, while the oxygen extraction ratio was higher in group 2. Free haemoglobin reached a maximal concentration of 1.0 +/- 0.2 g.dl-1 30 min after the HBOC-201 infusion was started, but was not detectable in urine over time. The mean intravascular half-life of HBOC-201 was 8.5 h.

CONCLUSIONS

Patients did not show any severe complications during and after infusion of HBOC-201. However, vasoconstrictive side effects resulted in increased systemic but not pulmonary resistance. Ongoing studies with higher doses of HBOC-201 applied in a larger number of patients will probably reveal potential clinical consequences of the demonstrated haemodynamic changes.

[Surgical therapy of primary and secondary liver tumors]

Advances in operative, diagnostic and post-operative care technique have rendered liver resections safe. Consecutively, indications for operative interventions in primary and secondary liver tumors have changed. A current state of the art is presented. Focal nodular hyperplasia, if found incidentally during laparotomy, should be removed en-passant. Large or central lesions should be biopsied and can be observed if they remain asymptomatic and stable in size. Symptomatic or growing FNH should be removed. If the diagnosis is evasive resection should be favored. Most patients with hepatocellular adenoma are symptomatic and the lesion should therefore be removed. Hemangiomas are rarely causing symptoms. In case they truly are, or if they cause complications they should be excised. Anatomical resections for hepatocellular carcinoma are only feasible in non-cirrhotic livers or in patients with cirrhosis and compensated liver function. Other patients are candidates for liver transplantation if the cancer is stage I or II. Stage III and IVa lesions are subject of current studies. Surgical resection remains the only potentially curative treatment for intrahepatic cholangiocellular carcinoma. Because of their dismal prognosis these patients are not candidates for transplantation. Resection continues to be the most effective therapy for colorectal metastases to the liver. Patients with non-colorectal, non-neuroendocrine metastases are usually only candidates for surgical palliation. Cure can be achieved in patients with renal cell carcinoma or Wilms' tumor. Additionally, neuroendocrine metastases to the liver can be resected in curative intent if extrahepatic disease was excluded. In the few symptomatic patients in whom extrahepatic disease was excluded, symptomatic treatment has failed, and the lesions are not resectable, liver transplantation can provide a reasonable therapeutic choice.

In situ splitting of cadaveric livers. The ultimate expansion of a limited donor pool

OBJECTIVE

The authors evaluate the safety, applicability, and effectiveness of a new technique for split-liver transplantation.

SUMMARY BACKGROUND DATA

Split-liver transplantation offers an attractive way to increase the donor pool for cadaveric liver transplantation. The application of this concept has been hampered by inferior patient and graft survivals and higher complication rates. Without supportive data, the concern about increasing biliary leakage and poor initial graft function persisted. The authors focused on the causes of these complications by presenting a new technique to eliminate these problems.

METHODS

Liver splitting was performed in the heart-beating cadaveric organ donor, using the technique described for procurement of the left lateral lobe of a live donor. A detailed description of the technique is presented. A retrospective review of the first 14 transplantations resulting from 7 in situ splitting procedures was collected. The results were compared with 19 conventional split-liver transplants performed during the same period.

RESULTS

Six-month patient and graft survivals after in situ split-liver transplantation were 92.8% and 85.7%, respectively. Biliary complications were absent. Postoperative courses were mostly uneventful and characterized by lower peak transaminase levels compared with standard techniques. Early graft function of extrahepatic organs procured simultaneously was excellent.

CONCLUSIONS

In situ split-liver transplantation provides superior results, related mainly to reduction of cold ischemic damage of the grafts and avoidance of biliary complications. In situ split-liver transplantation renders graft reduction alone obsolete and opens a donor pool for adults to receive right lobes safely. It allows for long-distance sharing between pediatric and adult liver transplant units because the procedure abolishes ex situ benching and prolonged ischemia time and provides two anatomically perfect grafts with hemostasis accomplished.

[Liver transplants from living donors]

In this article the authors discuss the advantages of Living Related Liver Transplantation (LRLT), criteria for the selection of donors and the standard operation technique. Among a total of 241 liver transplantation (LTx), 42 LRLT were performed at the University of Hamburg between October 1, 1991 and December 19, 1994. The body weight of recipients for LRLT ranged from 4,6 to 39 kg, with 64,2% having less than 10 kg. The volume of the donor left lateral liver lobe ranged from 100 cc to 350 cc. The average one year survival rate among electively operated patients-status 3-4 (UNOS 1995 classification) was 86.7%, two year survival rate 83.3%. The main advantages of LRLT are consired the following: 1. Absence of mortality on the waiting list, 2. Optimal timing of the transplantation (elective procedure, patient in a good condition), 3. Excellent organ (no primary non function), 4. A possible immunologic advantage, 5. Relief of the waiting list for cadaveric organs, 6. Psychological benefit for the family, 7. Cost effectiveness. Potential candidates for living donation with more than one cardiovascular risk factors were excluded. Social and psychological reasons leading to rejection of candidates were as follows: unstable family structure, expected professional or financial difficulties after living donation or withdrawal from consent. LRLT gives parents of a child with TLD a chance to avoid the risk of death on the waiting list or primary non function of the graft. LRLT has therefore established an important place in pediatric liver transplantation.

Living donor for liver transplantation

Since living related liver transplantation was first performed in 1989, more than 150 cases have been performed worldwide, mostly in the United States and Japan. This paper reports the first series of living related liver transplantation in Europe. Twenty living related liver transplantation surgeries were performed over a 13-mo period, with an overall patient survival of 85%. For patients who underwent elective transplantation (n = 13), the survival rate was 100%. Technical complications included one arterial thrombosis necessitating retransplantation and five bile leaks requiring surgical revision. The technical improvements that permit avoidance of these complications are discussed. A detailed description of the living related liver procurement is given. All procurements yielded grafts of excellent quality. No intraoperative complications occurred, and no reoperations were necessary. No heterologous blood transfusion was needed. In two patients, incisional hernias developed after wound infection. Living related liver transplantation does not absolve the transplant community of efforts to promote cadaveric organ procurement. Nevertheless, living related liver transplantation does have the advantage of a readily available graft of excellent quality, permitting transplantation with optimal timing under elective conditions. Several centers are now preparing living related segmental liver transplants, following the model of our protocol, for three reasons: (a) to obtain superior results compared with cadaveric liver transplantation; (b) to overcome cadaveric organ shortage and further reduce pretransplantation mortality and (c) to provide viable organs in countries where cadaveric organ procurement is not established. When performed by a team experienced in pediatric liver transplantation and in adult liver resection, living related liver transplantation is an excellent modality for the treatment of end-stage liver disease in children.

Living donor for liver transplantation

Since living related liver transplantation was first performed in 1989, more than 150 cases have been performed worldwide, mostly in the United States and Japan. This paper reports the first series of living related liver transplantation in Europe. Twenty living related liver transplantation surgeries were performed over a 13-mo period, with an overall patient survival of 85%. For patients who underwent elective transplantation (n = 13), the survival rate was 100%. Technical complications included one arterial thrombosis necessitating retransplantation and five bile leaks requiring surgical revision. The technical improvements that permit avoidance of these complications are discussed. A detailed description of the living related liver procurement is given. All procurements yielded grafts of excellent quality. No intraoperative complications occurred, and no reoperations were necessary. No heterologous blood transfusion was needed. In two patients, incisional hernias developed after wound infection. Living related liver transplantation does not absolve the transplant community of efforts to promote cadaveric organ procurement. Nevertheless, living related liver transplantation does have the advantage of a readily available graft of excellent quality, permitting transplantation with optimal timing under elective conditions. Several centers are now preparing living related segmental liver transplants, following the model of our protocol, for three reasons: (a) to obtain superior results compared with cadaveric liver transplantation; (b) to overcome cadaveric organ shortage and further reduce pretransplantation mortality and (c) to provide viable organs in countries where cadaveric organ procurement is not established. When performed by a team experienced in pediatric liver transplantation and in adult liver resection, living related liver transplantation is an excellent modality for the treatment of end-stage liver disease in children.

Intestinal allograft survival in the rat following pretreatment with donor-specific UV-B-irradiated leukocytes and peritransplant immunosuppression with cyclosporine

Previous studies from our laboratory showed that pretreatment with ultraviolet-B-irradiated donor leukocytes (UV-B DL) combined with brief peritransplant cyclosporine (CyA) resulted in indefinite survival of Wistar/Furth rat cardiac allografts in Lewis recipients. This study was designed to examine the effect of pretransplant UV-B DL with or without peritransplant CyA on orthotopic intestinal allografts in the same rat strain combination. The results showed that while low-dose CyA treatment alone (10 mg/kg i.m. on days 0, +1, and +2) had no effect on intestinal allograft rejection, 20 mg/kg (on days 0, +1, and +2) CyA significantly (P less than or equal to 0.001) prolonged graft survival, with 33% of the hosts surviving indefinitely. The highest dose of CyA (30 mg on days 0, +1, and +2) abrogated rejection, but most transplant recipients succumbed to infection and functional ileus due to a toxic side effect of CyA. Pretreatment with UV-B DL on days -14 and -7 alone did not prolong intestinal allograft survival. Combination of a subtherapeutic CyA dose (20 or 10 mg/kg) given on days 0, +1, and +2 with pretransplant UV-B DL on days -14 and -7 did not alter the survival of intestinal allografts compared to treatment with CyA alone. This suggests that pretreatment with UV-B DL with or without peritransplant administration of CyA has no effect on intestinal allograft survival, in contrast to the effect of such combined treatment on cardiac allograft survival, where indefinite graft survival is observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential effects of pretreatment with ultraviolet-B modified or unmodified donor-specific leukocyte transfusions on intestinal and cardiac allograft survival in the rat

This study compares the effects of pretreatment with donor-specific leukocytes (DL) or UV-B irradiated donor-specific (UV-B DL) transfusion on day -7 relative to organ transplantation, in the induction of specific immunologic unresponsiveness to intestinal and cardiac allografts in the Lewis-to-ACI rat strain combination. Recipients of orthotopic small intestinal allografts, who were pretreated with UV-B DL survived for 7.2 +/- 3.6 days compared with 7.5 +/- 0.5 days in the control group. Pretreatment with unmodified DL induced hyperacute rejection of intestinal allografts, suggesting a sensitizing effect of DL in this model. In contrast, pretreatment with DL and UV-B DL transfusions significantly prolonged cardiac allograft survival with 25% (DL) and 50% (UV-B DL) of the grafts surviving indefinitely (greater than 120 days). To define the underlying mechanisms of the differential effects of DL and UV-B DL pretreatment on intestinal and cardiac allograft survival, we evaluated the ability of DL and UV-B DL transfusions to induce alloantibodies and donor-directed cytotoxic T lymphocytes (CTL). The finding that recipients of DL developed donor-specific cytotoxic alloantibodies and CTL may partially explain the accelerated rejection of intestinal allografts in such recipients while the disparity of the findings in cardiac and intestinal transplantation may be due to a higher affinity of the induced cytotoxic alloantibodies to antigens on the intestine than on the heart. Since UV-B DL pretreatment prevents the induction of cytotoxic alloantibodies and CTL, there is a significant difference in recipients transfused with DL as compared with UV-B DL. The proliferative response to donor alloantigens (MLR) of lymphocytes obtained from DL and UV-B DL pretreated animals was down-regulated as compared with the MLR response of lymphocytes obtained from unmodified animals. Subsequent coculture experiments demonstrated the appearance of suppressor cells following pretreatment with DL and UV-B DL. While DL and UV-B DL transfusions significantly increased cardiac allograft survival, there was no prolongation of intestinal allografts in our model despite the abrogation of the sensitizing effect of DL transfusions by prior UV-B irradiation. These differential effects on graft survival emphasize the importance of specific organ immunogenicity.

[Small intestine transplantation--a causal therapy in short bowel syndrome]

The problems of surgical technique, graft physiology and immunological reactions in small-bowel transplantation have been investigated in extended animal experiments. In these experiments, the fundamentals of a successful clinical application of small-bowel transplantation could be laid. A successful human small-bowel transplantation could be carried out by the Kiel Group for the first time in 1988. A graft which had been removed from a related donor showed a complete adaptation after 22 months, so that the patient became completely independent from parenteral nutrition. After that, in several cases small-bowel and combined liver and small-bowel transplantation have been carried out. Thus, the clinical small-bowel transplantation represents the causal therapy of short-bowel syndrome and should be developed in further clinical trials.

Small bowel transplantation

Small intestinal transplantation has had several clinical attempts based on extensive experimental work during the past two decades. Several models, such as auxiliary (heterotopic) or orthotopic models, have been developed in regard to problems with graft immunology and function. The question of mesenteric-portal or mesenteric-caval graft drainage was raised, and the answer seems to be open. Concerning lipid absorption, interest was directed to the reconstitution of lymphatic vessels, because orally administered cyclosporine A is absorbed by the lipid mechanism. Carbohydrate digestion and absorption are used for determination of graft function and for monitoring graft rejection. This article summarizes these problems and deals with the surgical procedure of small bowel transplantation in the rat.

Small bowel transplantation in a child. Morphologic, immunohistochemical, and clinical results

A small bowel transplant was performed on a five-year-old boy with a short bowel syndrome. The donor was the child's mother. Despite immunosuppressive therapy, the transplant was acutely rejected and had to be explanted on the twelfth day. Morphologic and immunohistochemical investigations on subsequent biopsies taken from the small bowel transplant were carried out. Besides typical changes in epithelial cells and the presence of T-cell infiltrates and Ig-deposits in vessels, many macrophages were seen. The submucosa in particular was invaded before rejection by numerous macrophages with positive results of antimonocyte/macrophage antibodies Ki-M6 and Ki-M7. The number of the macrophage antibodies Ki-M6 and Ki-M7. The number of the monocyte/macrophage cells and the immunohistochemical characteristics of the same may be important parameters for monitoring small bowel transplantations.