Characteristics of Liver Transplantation in Argentina: A Multicenter Study

INTRODUCTION

There is a lack of information regarding outcomes after liver transplant in Latin America.

OBJECTIVES

This study sought to describe outcomes after liver transplant in adult patients from Argentina.

METHODS

We performed an ambispective cohort study of adult patients transplanted between June 2010 and October 2012 in 6 centers from Argentina. Only patients who survived after the first 48 hours postransplantation were included. Pretransplantation and posttransplantation data were collected.

RESULTS

A total of 200 patients were included in the study. Median age at time of transplant was 50 (interquartile range [IQR] 26 to 54) years. In total, 173 (86%) patients had cirrhosis, and the most frequent etiology in these patients was hepatitis C (32%). A total of 35 (17%) patients were transplanted with hepatocellular carcinoma. In patients with cirrhosis, the median Model for End-Stage Liver Disease (MELD) score at time of liver transplant was 25 (IQR 19 to 30). Median time on the waiting list for elective patients was 101 (IQR 27 to 295) days, and 3 (IQR 2 to 4) days for urgent patients. Almost 40% of the patients were readmitted during the first 6 months after liver transplant. Acute rejection occurred in 27% of the patients. Biliary and vascular complications were reported in 39 (19%) and 19 (9%) patients, respectively. Renal failure, diabetes, and dyslipidemia were present in 40 (26%), 87 (57%), and 77 (50%) at 2 years, respectively.

CONCLUSIONS

We believe the information contained in this article might be of value for reviewing current practices and developing local policies.

[Pharmacovigilance of calcineurin inhibitor in peidatric kidney and liver transplantation]

AIM

To develop a pharmacovigilance program of calcineurin inhibitors used in pediatric renal and liver transplant patients at Hospital de Pediatría JP Garrahan, Argentina.

METHODS

Adverse drug reactions (ADRs) of pediatric patients with kidney and liver transplantation treated with calcineurin inhibitors (cyclosporine and tacrolimus) were evaluated by retrospective review of medical records of patients transplanted between 2010 and 2011. In addition, we carried out active pharmacovigilance since March, 2011. ADRs were reported to the National Health Authority.

RESULTS

A total of 59 patients, 28 kidney transplant and 31 liver tarnsplant patients were analyzed. In both transplants, 60 ADRs to cyclosporine were reported including (number of cases), hypertension (19) and nephrotoxicity (6). In addition, 46 ADRs to tacrolimus were registered as hypomagnesemia (25), hypertension (7) and nephrotoxicity (5). A total of 95% and 96% of the adverse events to cyclosporine and tacrolimus, respectively, were defined as probable or definitive. Lastly, 70% and 98% of the events to cyclosporine and tacrolimus respectively, have been moderately severe or severe.

CONCLUSIONS

This is the first study in Latin America that developed an intensive qualitative and quantitative analysis of the ADRs to calcineruin inhibitors in pediatric kidney and liver transplant patients. Spontaneous reporting should be motivated as well as monitoring ADRs should continue in the medium and long term for improving patient's quality of life.

[Surgical risk scale in pediatric surgery]

INTRODUCTION

The need to measure the level of surgical risk arises from its direct relationship with the development of postoperative complications and the use of hospital resources. The construction of a surgical risk scale (ERQ) for pediatric surgery should be based on a common language, by using a small number of easy to collect and reproduce variables. The objectives of this study were to construct an ERQ for pediatric patients and to analyze the surgical performance.

MATERIALS AND METHODS

We retrospectively analyzed 105 primary surgical procedures under general anesthesia performed by liver transplantation service at Hospital Garrahan, between 29/6/08 and 25/3/10. Newborn patients were not considered. The ERQ was built by adding patient risk factors (PRL): weight (< o > 10 kg), co-morbidities (coagulopathy-obesity-diabetes) and life support; and the magnitude level of the surgical procedure (SPL): surgical time and requirement of blood transfusions. The surgical performance was considered as a relation between the level of surgical risk and the post-operative results, measured with the classification of surgical complications proposed by Clavien et al (STROC). The main end point of the study was the STROC > or = 3 (severe complications). The ERQ predictive power for serious complications was compared with the anaesthetic risk (ASA). Descriptive and analytical statistics took place. The predictive value for complications was calculated by means of a ROC curve. The estimation of the risk was calculated by relative risk.

RESULTS

The ERQ was constituted on a continuum of 6 risk levels (2 to 7). The ROC's curve predictive power to determine the development of severe post-operative complications (STROC > or = 3) was 0.87 (CI 0,80-0,94) for the ERQ and 0.81 (CI 0,73-0,89) for the ASA. Level of > or = 5 of ERQ was the cut-off point that better predicted the development of STROC > or = 3.

CONCLUSION

The ERQ is an easy tool, useful to quantify and compare surgical risks and results. It showed a high predictive power of postoperative complications.

Model for end-stage liver disease-based allocation system for liver transplantation in Argentina: does it work outside the United States?

BACKGROUND

In July 2005, Argentina was the first country after the United States to adopt the MELD system. The purpose of the present study was to analyse the impact of this new system on the adult liver waiting list (WL).

METHODS

Between 2005 and 2009, 1773 adult patients were listed for liver transplantation: 150 emergencies and 1623 electives. Elective patients were categorized using the MELD system. A prospective database was used to analyse mortality and probability to be transplanted (PTBT) on the WL.

RESULTS

The waiting time increased inversely with the MELD score and PTBT positively correlated with MELD score. With scores >/= 18 the PTBT remained over 50%. However, the largest MELD subgroup with <10 points (n = 433) had the lower PTBT (3%). In contrast, patients with T(2) hepatocellular carcinoma benefited excessively with the highest PTBT (84.2%) and the lowest mortality rate (5.4%). The WL mortality increased after MELD adoption (10% vs. 14.8% vs. P < 0.01). Patients with <10 MELD points had >fourfold probability of dying on the WL than PTBT (14.3% vs. 3%; P < 0.0001).

CONCLUSIONS

After MELD implementation, WL mortality increased and most patients who died had a low MELD score. A comprehensive revision of the MELD system must be performed to include cultural and socio-economical variables that could affect each country individually.

Combined cardiohepatic transplantation due to severe heterozygous familiar hypercholesteremia type II: first case in Argentina--a case report

Heterozygous familial hypercholesteremia type II is a recessive autonomic disease with a population incidence <or=1:500. It develops as a consequence of a mutation in the LDLR gene. Patients suffer extremely high LDL and VLDL cholesterol values, dying from coronary compromise at early ages. As cholesterol synthesis is an hepatic process, and as there is a lack of gene therapy, hepatic transplantation is the only therapeutic option in cases refractory to medical treatment. In this report, we have described the first case of combined cardiohepatic transplantation in Argentina, which was performed in a male patient with severe aortic stenosis and terminal ischemic cardiopathy secondary to severe familial hypercholesteremia type II.

Liver resection for non-colorectal, non-neuroendocrine metastases: analysis of a multicenter study from Argentina

BACKGROUND AND AIM

Resection of colorectal liver metastases has become a standard of care, although the value of this procedure in non-colorectal non-neuroendocrine (NCRNNE) metastases remains controversial and is still a matter of debate. The aim of the study was to determine the utility of liver resection in the long-term outcome of patients with NCRNNE metastases.

MATERIAL AND METHODS

The records of 106 patients who underwent liver resection for NCRNNE metastases in the period 1989 to 2006 at 5 HPB Centers in Argentina were analyzed. Patient demographics, tumor characteristics, type of resection, long-term outcome and prognostic factors were analyzed. Depending on primary tumor sites, a comparative analysis of survival was performed.

RESULTS

Mean age was 54 (17-76). Hepatic metastases were solitary in 62.3% and unilateral in 85.6%. Primary tumor sites: Urogenital (37.7%), sarcomas (21.7%), breast (17.9%), gastrointestinal (6.6%), melanoma (5.7%), and others (10.4%). Fifty-one major hepatectomies and 55 minor resections were performed. Twenty patients underwent synchronous resections. An R0 resection could be achieved in 89.6%. Perioperative mortality was 1.8%. Overall, 1-year, 3-year, and 5-year survival rates were 67%, 34%, and 19%, respectively. Survival was significantly longer for metastases of urogenital (p=0.0001) and breast (p=0.003) origin. Curative resections (p=0.04) and metachronous disease (p=0.0001) were predictors of better survival.

CONCLUSIONS

Liver resection is an effective treatment for NCRNNE liver metastases; it gives satisfactory long-term survival especially in metachronous disease, in patients with metastases from urogenital and breast tumors and when R0 procedures can be performed.

Liver transplantation in adult patients with portal vein thrombosis: risk factors, management and outcome

BACKGROUND

Portal vein thrombosis (PVT) is a well recognized complication of patients with end-stage cirrhosis and its incidence ranges from 2 to 26%. The aim of this study was to analyze the results and long-term follow-up of a consecutive series of liver transplants performed in patients with PVT and compare them with patients transplanted without PVT.

PATIENTS AND METHODS

Between July 1995 and June 2006, 26 liver transplants were performed in patients with PVT (8.7%). Risk factors and variables associated with the transplant and the post-transplant period were analyzed. A comparative analysis with 273 patients transplanted without PVT was performed.

RESULTS

The patients comprised 53.8% males, average age 40, 7 years. PVT was detected during surgery in 65%. Indications for transplantation were: post-necrotic cirrhosis 73%, cholestatic liver diseases 23%, and congenital liver fibrosis 4%. Child-Pugh C: 61.5%. Techniques were trombectomy in 21 patients with PVT grades I, II, IV, and extra-anatomical mesenteric graft in 5 with grade III. Morbidity was 57.7%, recurrence of PVT was 7.7%, and in-hospital mortality was 26.9%. Greater operative time, transfusion requirements, and re-operations were found in PVT patients. One-year survival was 59.6%: 75.2% for grade 1 and 44.8% for grades 2, 3, and 4.

DISCUSSION

The study demonstrated a PVT prevalence of 8.7%, a higher incidence of partial thrombosis (grade 1), and successful management of PVT grade 4 with thrombectomy. Liver transplant in PVT patients was associated with an increased operative time, transfusion requirements, re-interventions, and lower survival rate according to PVT extension.

Nitric oxide in liver transplantation

Liver transplantation is the only therapeutic option for patients with end-stage liver disease. Nitric oxide, a free radical produced from L-arginine, a potent vasodilator, also inhibits platelet adhesion and aggregation, reduces adhesion of leukocytes to the endothelium and suppresses proliferation of vascular smooth muscle cells. The inducible form of the nitric oxide synthase may generate large quantities of nitric oxide, and may be induced by the action of cytokines and lipopolysaccharides. Nitric oxide can be released from the hepatic vascular endothelium, platelets and Kupffer cells as a response to ischemia-reperfusion injury and circulatory shock. We analyzed the relationships between the levels of nitric oxide, hepatic enzymes and other clinical parameters (glucose, total proteins, total bilirubin, creatinine, albumin) obtained in serum samples before liver transplantation and every 48 h till day 15 in 15 patients aged 40 +/- 13 years. Aspartate aminotransferase and alanine aminotransferase levels changed from high at the beginning, to almost normal at the end of the study, cholinesterase levels remained decreased throughout the study and nitric oxide remained high, never reaching normal values.

[Autoimmune hepatitis in children. Initial presentation as fulminant hepatic failure]

There are few cases reported of autoimmune hepatitis (AIH) type 2 presenting as fulminant hepatic failure (FHF) in children. The purpose of this study was to report three girls with AIH type 2 that presented as FHF.

METHODS

Over a period of 12 years, 123 patients with AIH diagnosed based on international criteria, 9 (7%) were type 2.3 of them presented as FHF. Other etiologies (viral, metabolic and toxic) were ruled out. The treatment was started with prednisone (2 mg-kg-day) and azathioprine (2 mg-kg-day).

EVOLUTION

Patients 1 and 3 died while waiting for liver transplant (LT) at 72 and 48 hours after initiating medical treatment. Patient 2 underwent LT3 days after starting treatment, with excellent evolution at 3 years and 7 months of follow up.

CONCLUSIONS

1--AIH type 2 was very infrequent in our group. 2--33% of cases had initial presentation as FHF. 3--The course of the disease was aggressive, not responding to immunosuppressive therapy. The evolution was unfavorable in all patients. 4--LT is an alternative treatment for this severe disease.

Liver transplantation in transthyretin familial amyloid polyneuropathy: first report from Argentina

This is the first report from Argentina of liver transplantation in patients with transthyretin related familial amyloidotic polyneuropathy. The aims of the study were to analyze the clinical characteristics of this new focus and evaluate the postoperative complications and long term follow up. Five of ten patients evaluated underwent liver transplantation. During the waiting period the polyneuropathy disability score in each patient progressed one or two stages. Pretransplant modified body mass index was 723. The procedure was done with full size grafts in four cases and a split right graft in one. All patients presented postoperative complications related to disease: severe edema of the legs, recurrent choledochal lithiasis, postoperative hernia, necrotizing fasciitis and ischemic rectosigmoidal perforation. Assessment of three patients after 20 months of transplantation showed improvement in somatic and mental symptoms. No improvement was noted in cardiac denervation and gastric stasis. Liver transplantation is a rational therapeutic option for transthyretin familial amyloidotic polyneuropathy in Argentina and should be indicated in earlier stages of the symptomatic disease to reduce the postoperative morbidity and mortality. Family studies and follow up of asymptomatic carriers will define the epidemiological behavior in this country and facilitate early therapeutic intervention.

Development of a pediatric liver transplantation program in Argentina

This article describes the preliminary experimental steps and clinical implementation of a purely pediatric liver transplantation (LT) program in a large public children's hospital in Buenos Aires, Argentina, a city with well over 10 million inhabitants and a referral population of over 30 million. Between 1993 and 1997, 84 LTs were performed in 81 patients, of which one-fourth weighed below 10 kg. The main indications were biliary atresia (n = 25, 30%) and fulminant liver failure (n = 23, 27%), followed by autoimmune cirrhosis (n = 14, 16%) and other liver diseases. Shortage of organs due to local conditions led to the use of liver-reduction techniques in 48 cases (57%), split liver in 2, and living-related donor (LRD) in 2. Retransplantation was necessary in 3 instances. Seventy-eight percent of the recipients survived for more than 1 year and 71% were alive after 4 years. The authors comment on the need for adaptation to local conditioning factors when developing a pediatric LT program in any country in which demographics and economic, medical, and sociological environments have a decisive influence on organ procurement, the actual performance of the operation, and the lifelong postoperative medication. In Buenos Aires, where the hospital setting is well-developed, the indications are in part determined by the high incidence of hepatitis A. Organ shortages in our area led to liberal use of liver reduction, split-liver, and LRD techniques. The overall results of the first years of such a program were largely satisfactory.

Pediatric liver transplantation from neonatal donors

Sixteen recipients of neonatal liver grafts were compared with 114 contemporaneous pediatric recipients of grafts from older donors. Graft and patient survival were worse in the neonatal group although the differences were not statistically significant. Patients with neonatal livers who had no technical complications required a longer time postoperatively to correct jaundice and a prolonged prothrombin time. These functional differences were limited to the 1st postoperative month and the end result was the same as with liver transplantation from older donors.

The effect of bile duct ligation and bile diversion on FK506 pharmacokinetics in dogs

Mongrel or beagle dogs were submitted to bile duct ligation, or to extraenteric biliary diversion by means of choledochoureterostomy. The kinetics of intravenously administered FK506 was not changed from control status two weeks after bile duct ligation, but the bioavailability of orally administered FK506 was nearly quadrupled. Following oral administration, the absorption of FK506 was highly variable. The results indicate that in dogs FK506 is absorbed from the intestine just as efficiently in the absence of enteric bile and in presence of exogenous bile salt supplement when compared with its absorption in presence of normal bile drainage. These findings with FK506 are different from those with cyclosporine after biliary obstruction or diversion and will have important practical as well as experimental ramifications.

Effect of cold ischemia time on the early outcome of human hepatic allografts preserved with UW solution

Five hundred ninety-three cadaveric livers were used for primary liver transplantation between October 24, 1987, and May 19, 1989. The grafts were procured with a combined method, using in situ cooling with cold electrolyte solution and backtable flushing with UW solution. The mean cold-ischemia time was 12.8 (range 2.4-34.7) hr. The cases were divided into 5 groups according to the cold-ischemia time: group 1: less than 10 hr (n = 223); group 2: 10-14 hr (n = 188); group 3: 15-19 hr (n = 101); group 4: 20-24 hr (n = 52); and group 5: greater than or equal to 25 hr (n = 29). There was no difference between the 5 groups in 1-year patient survival, highest SGOT in first week after operation, and SGOT and total bilirubin during the first month after operation. However, with a logistic regression model, the retransplantation rate (P = 0.001) and primary nonfunction rate (P = 0.006) significantly rose as cold-ischemia time increased, meaning that the equivalency of patient survival was increasingly dependent on aggressive retransplantation.

Induction of graft acceptance after dog kidney or liver transplantation

We have reported that, a short delayed course of intramuscular FK 506 can induce a,donor strain-specific immunologic unresponsiveness to cardiac allograft in rats.1 Further studies have been performed to determine if this agent can induce graft acceptance after canine renal (KT) or hepatic (OLT) allotransplantation. Preliminary descriptions of these efforts have been published.2

Tube choledochoureterostomy: a simple method for bile diversion

A technique of bile diversion by tube choledochoureterostomy has been devised for the purpose of studying the role of bile in the intestinal absorption of drugs. This method was used in six dogs. No technical difficulties or major complications developed, as are inevitable with alternative methods, including external fistula.

The UW solution for canine kidney preservation. Its specific effect on renal hemodynamics and microvasculature

The preservation effects of UW solution on renal hemodynamics and microvascular systems were studied in canine kidney autografts. In 72-hr UW-preserved kidneys, the microvessels of both cortex and medulla were completely visualized with silicon rubber compound 1 hr after reperfusion. Histology also showed extremely well-preserved arterioglomerular and tubular systems. These results were correlated with good renal blood flow, prompt recovery of posttransplant graft function, and 100% two-week survival of dogs. In contrast, kidneys preserved for 72 hr with Euro-Collins solution showed necrotic and obstructive changes of the microvasculature and deterioration of renal hemodynamics. In 120-hr UW-preserved kidneys, the microcirculation of the medullary region became poor after reflow when there was fairly intact perfusion of the cortical region, indicating an ischemia-related intrarenal blood flow maldistribution. The 120-hr kidneys subsequently failed in spite of having a good blood flow and morphologically well-maintained microvasculature after reperfusion. These data demonstrated that much, but not all, of the beneficial effect of UW solution in kidney preservation might be attributed to its remarkable protection of renal microvasculature. Correction of intrarenal blood maldistribution caused by a discrepancy in tolerance to ischemia of the vascular and tubular systems might be important in successfully preserving the kidney for 120 hr.

Comparison of UW with other solutions for liver preservation in dogs

The efficacy of the University of Wisconsin (UW) solution was compared with conventional Euro-Collins solution, as well as with 3 variants of a silica gel solution developed at the University of Minnesota (UM). Protection of the liver grafts with UW was superior after 24 hour preservation, although the results were inferior to those with immediate transplantation, as judged by animal survival, liver function tests, coagulation, and histopathologic parameters. The UM-III solution allowed similar animal survival as with the UW solution. Lactobionate and raffinose that are contained in both the UW and UM-III solutions were thought to be essential constituents for long-term preservation of liver grafts. The study not only establishes, under controlled circumstances, the superiority of the UW solution, but it also provides insight about the reasons for its effectiveness as well as a caution against its over exploitation.

Renal transplantation in baboons under FK 506

FK 506 was tested in unrelated baboons submitted to renal transplantation and bilateral native nephrectomy. Untreated baboons died after 9.2 +/- 4.0 SD days. When FK 506 was given orally for 90 days, survival with the optimum dose was 74.6 +/- 28.9 days; this allowed maximum credit for each individual animal of 90 days. A 3-day course of intramuscular FK 506 started on postoperative day 4 allowed 1- to 2-month survival. Delayed rejection in these baboons as well as in those treated daily for 90 days with FK could sometimes be reversed temporarily with a second 3-day course. The doses required for a good therapeutic effect were 10 times greater in baboons than in dogs, a finding that may reflect a species difference of lymphocyte sensitivity to this drug. FK appeared to be relatively nontoxic in subhuman primates, and it remains a promising drug for clinical trial.

Immunosuppression of canine, monkey, and baboon allografts by FK 506: with special reference to synergism with other drugs and to tolerance induction

In dogs the most effective oral dose of FK 506 for prevention of renal homograft rejection was 1.5 mg/kg/day. With maximum credit allowed at 90 days, survival was increased to 61.0 +/- 33.6 (SD) days compared with 13.0 +/- 4.1 in untreated control animals. Higher doses were toxic. The smallest dose that was used (0.5 mg/kg/day) prolonged survival after renal transplantation to 33.7 +/- 23.9 (SD) days. When the small dose of FK 506 was combined with 5 mg/kg/day of cyclosporine and 5 mg of prednisone, five of six canine kidney recipients lived for 90 days. These results were degraded by omission of any of the constituent drugs or reduction by half of the triple drug doses. Thirteen of the dogs treated with various drug regimens lived for 90 days, after which time treatment was stopped; 10 of the dogs eventually rejected the grafts, but three had continued graft function for 6 months or longer and may be permanently tolerant. Moreover, in dogs when 1 mg/kg of intramuscular FK was given to 19 kidney and seven liver recipients for 3 days on postoperative days 1 to 3, 4 to 6, or 7 to 9, the animals survived subsequently for 11 to more than 160 days. All but four of the grafts were eventually rejected, but the prolonged effect of a short course of delayed therapy suggests the possibility of tolerance induction. In cynomolgus monkeys and baboons, FK as a single drug was found to be immunosuppressive after kidney transplantation. Correlation in the dogs and primates between immunosuppression, toxicity, and FK blood levels was not possible because of presently imperfect standardization of assay and monitoring techniques. FK had serious side effects in dogs, but not so obviously in monkeys and not at all in baboons.

Effect of FK506 in experimental organ transplantation

FK506 is the most potent immunosuppressive agent known. Its toxicity is substantial in dogs, minor in rats, and unknown in subhuman primates. In small doses that are nontoxic even in dogs, it can be used in synergistic combination with cyclosporine, steroids, and presumably in other drugs.

Orthotopic liver transplantation in dogs receiving FK-506

Ten dogs that survived the perioperative events of liver transplantation were treated with 1 mg/kg/d oral FK. Eight of the recipients lived for at least 1 month postoperatively, and seven are still alive with normal hepatic function after 35 to 65 days. The consistency and good quality of results with this difficult transplant preparation using FK, in spite of its rumored great toxicity in dogs, have highlighted the importance of further developing the drug.

Canine kidney transplantation with FK-506 alone or in combination with cyclosporine and steroids

The immunosuppressive agent FK permitted increased kidney transplant survival in dogs over a wide dose range, but with weight loss and manifold evidence of toxicity. The best use of FK at low doses was in combination with CyA and Pred.