Clinical symptomatic de novo systemic transthyretin amyloidosis 9 years after domino liver transplantation

Safety, Tolerability, and Outcomes of Tafamidis for the Treatment of Acquired Amyloid Neuropathy in Domino Liver Transplant Recipients

INTRODUCTION

Acquired amyloid neuropathy is an iatrogenic disease that appears years after a domino liver transplant. The objectives of our study are to analyze the efficacy and tolerability of tafamidis for the treatment of acquired amyloid neuropathy in domino liver transplant recipients. This post-authorization, prospective, longitudinal study included seven domino liver transplant recipients with acquired amyloid neuropathy who received treatment with tafamidis for 18 months.

METHODS

The primary endpoints were the response rate, defined as those patients with an increase of < 2 points on the Neurological Impairment Score (NIS) from baseline, and the change in the NIS score from baseline. Secondary endpoints included the Quantitative Sensory Test, 10-m walk test, quality of life (Norfolk), and disability (Rasch-built Overall Disability Scale). As safety parameters, the evidence of graft rejection, changes in immunosuppressive trough levels and changes in antiviral and allogeneic cellular immunity before and 12 months after tafamidis treatment were also assessed.

RESULTS

Six patients (85.7%) had responded at 18-months. Compared to baseline, we observed non-statistically significant improvement in mean NIS score at 6 months (- 2.54 points, CI - 5.92 to 0.84), 12 months (- 3.25 points; CI - 6.63 to 0.13), and 18 months (- 2.35 points; CI - 5.74 to 1.02). Changes in the Quantitative Sensory Test, 10-m walk tests and the quality of life and disability questionnaires were not statistically significant. The use of tafamidis did not induce relevant side effects or drug interactions. Also, no acute rejections events nor changes in functional adaptive immunity were observed.

CONCLUSION

Our study supports the safety and tolerability of tafamidis for the treatment of acquired amyloid neuropathy in domino liver transplant recipients. Tafamidis shows promise as a useful treatment in the clinical management of these patients. Future randomized placebo-controlled clinical trials with longer follow-up durations are needed.

[de novo hATTR amyloidosis after domino transplantation of a donor's liver: a case report for the use of Patisiran]

Hereditary transthyretin-mediated (hATTR) amyloidosis is a rare, rapidly progressing, and potentially life-threatening disease caused by one of more than 120 mutations in the transthyretin (TTR) gene. As a result of the cumulative amyloid deposits, especially in the peripheral nerves and the heart, the majority of patients develop progressive, peripheral sensorimotor polyneuropathy and biventricular cardiomyopathy over time.Since TTR - and its amyloidogenic variants too - is predominantly synthesized in the liver, early, orthotopic liver transplantation (LTx) is a treatment option that can be used to potentially stop the progression of hATTR amyloidosis.The actual case shows a patient with hepatocellular carcinoma who received the organ of a patient with hATTR as part of a domino liver transplantation. After approximately 10 years, the patient started to develop the characteristic symptoms of the metabolic disorder. Because of a further progression of the amyloidosis, therapy with the RNA interference therapeutic patisiran was initiated, which temporarily halted the progression.

Treatment With Diflunisal in Domino Liver Transplant Recipients With Acquired Amyloid Neuropathy

Objectives: To analyze the efficacy and tolerability of diflunisal for the treatment of acquired amyloid neuropathy in domino liver transplant recipients. Methods: We performed a retrospective longitudinal study of prospectively collected data for all domino liver transplant recipients with acquired amyloid neuropathy who received diflunisal at our hospital. Neurological deterioration was defined as an score increase of ≥2 points from baseline on the Neurological Impairment Scale/Neurological Impairment Scale-Lower Limbs. Results: Twelve patients who had received compassionate use treatment with diflunisal were identified, of whom seven had follow-up data for ≥12 months. Five patients (71.4%) presented with neurological deterioration on the Neurological Impairment Scale after 12 months (p = 0.0382). The main adverse effects were cardiovascular and renal, leading to diflunisal being stopped in five patients and the dose being reduced in two patients. Conclusion: Our study suggests that most domino liver transplant recipients with acquired amyloid neuropathy will develop neurological deterioration by 12 months of treatment with diflunisal. This therapy was also associated with a high incidence of adverse effects and low treatment retention. The low efficacy and low tolerability of diflunisal treatment encourage the search for new therapeutic options.

Domino transplantation for pediatric liver recipients: Obstacles, challenges, and successes

BACKGROUND

Domino liver transplantation aims to address the need to increase the liver donor supply. In a domino liver transplant, the domino recipient receives the explanted liver from the recipient of a traditional liver transplant. The domino donor typically requires liver transplant to correct a metabolic disorder; the explanted liver thus has a single gene defect but otherwise normal structure and function.

METHODS

In this review, we detail the history of domino liver transplantation, appropriate domino donor indications, the technical advances to the surgical approach, current outcomes, and future opportunities.

RESULTS

Development of de novo disease in the domino recipient has relegated adult domino liver transplant to be considered a source of marginal donor livers. However, pediatric domino liver transplant has leveraged certain metabolic disorders, especially maple syrup urine disease, in which the liver enzyme deficiency can be compensated by the systemic presence of sufficient enzyme. Advances in the surgical aspects of assuring adequate length of vasculature have improved the safety of the procedure in both domino donors and recipients.

CONCLUSIONS

Pediatric domino liver transplant utilizing domino donors with specific metabolic liver diseases should be considered a viable live donor option for children awaiting liver transplant.

Transthyretin Amyloidosis: Update on the Clinical Spectrum, Pathogenesis, and Disease-Modifying Therapies

ATTR amyloidosis is caused by systemic deposition of transthyretin (TTR) and comprises ATTRwt (wt for wild-type) amyloidosis, ATTRv (v for variant) amyloidosis, and acquired ATTR amyloidosis after domino liver transplantation. ATTRwt amyloidosis has classically been regarded as cardiomyopathy found in the elderly, whereas carpal tunnel syndrome has also become a major initial manifestation. The phenotypes of ATTRv amyloidosis are diverse and include neuropathy, cardiomyopathy, and oculoleptomeningeal involvement as the predominant features, depending on the mutation and age of onset. In addition to variant TTR, the deposition of wild-type TTR plays a significant role, even in patients with ATTRv amyloidosis. The formation of amyloid fibrils tends to occur in association with the basement membrane. The thickening or reduplication of the basement membrane surrounding endoneurial microvessels, which is similar to diabetic neuropathy, is observed in ATTRv amyloidosis, suggesting that common mechanisms, such as an accumulation of advanced glycation end products, may participate in the disease process. In addition to direct damage caused by amyloid fibrils, recent studies have suggested that the toxicity of nonfibrillar TTRs, such as TTR oligomers, participates in the process of tissue damage. Although liver transplantation has been performed for patients with ATTRv amyloidosis since 1990, late-onset patients were not eligible for this treatment. However, as the efficacy of orally administered tafamidis and diflunisal, which stabilize TTR tetramers, was suggested in the early 2010s, such late-onset patients have also become targets for disease-modifying therapies. Additionally, recent studies of small interfering RNA (patisiran) and antisense oligonucleotide (inotersen) therapies have demonstrated the efficacy of these gene-silencing agents. A strategy for monitoring patients that enables the choice of an appropriate treatment from comprehensive and long-term viewpoints should be established. As many patients with ATTR amyloidosis are aged and have heart failure, they are at increased risk of aggravation if they are infected by SARS-CoV2. The optimal interval of evaluation should also be considered, particularly in this COVID-19 era.

Characteristics of acquired transthyretin amyloidosis: A case series and review of the literature

OBJECTIVE

To elucidate the clinical characteristics of acquired ATTR amyloidosis after domino liver transplantation (DLT) with liver grafts explanted from patients with hereditary variant ATTR (ATTRv) amyloidosis.

METHODS

We evaluated the presence of amyloid deposits and clinical symptoms in 30 recipients of domino liver transplants (24 men and 6 women) who underwent DLT with liver grafts explanted from patients with ATTRv amyloidosis. We analyzed symptoms and measures of 7 cases of symptomatic acquired ATTR amyloidosis and compared those with 30 patients with ATTRv amyloidosis who were the domino liver donors. We also reviewed the literature on case studies of acquired ATTR amyloidosis.

RESULTS

We found amyloid deposition in 13 of our 30 domino liver recipients. A Kaplan-Meier analysis estimated that the median time from DLT to the first detection of amyloid was 8.5 years. In the literature review, the mean time was 7.3 years, with a wide range of 0.5-13 years. Our 7 symptomatic cases and the literature cases with acquired ATTR amyloidosis presented with clinical features that differed from patients with ATTRv amyloidosis who were the domino liver donors. Patients with acquired ATTR amyloidosis showed markedly milder autonomic disturbance, which is one of the main symptoms of ATTRv amyloidosis.

CONCLUSIONS

Careful monitoring is required for DLT recipients of ATTRv liver grafts because the time from DLT to disease onset has a wide range and the clinical picture of these DLT recipients is distinct from that of liver donors.

Outcomes of domino liver transplantation compared to deceased donor liver transplantation: a propensity-matching approach

Domino liver transplantation (DLT) utilizes the explanted liver of one liver transplant recipient as a donor graft in another patient. While there may be unique risks associated with DLT, it is unclear if DLT has less favorable long-term outcomes than deceased donor liver transplantation (DDLT). We used a propensity score matching approach to compare the outcomes of DLT recipients to DDLT recipients. The United Network for Organ Sharing (UNOS) registry was queried for patients undergoing DLT or DDLT in 2002-2016. Each DLT recipient was matched to a unique DDLT recipient to compare mortality and graft failure. There were 126 DLT and 62 835 DDLT recipients meeting inclusion criteria. After propensity score matching on recipient pre-transplant characteristics, 123 DLT cases were matched to DDLT controls from the same UNOS region. On stratified Cox proportional hazards regression, DLT incurred no increase in the hazard of mortality [hazard ratio (HR) = 1.4; 95% confidence interval (CI): 0.8, 2.7; P = 0.265] or graft failure (HR = 1.2; 95% CI: 0.7, 2.1; P = 0.556) compared to DDLT. Using a large national registry, a propensity-matched analysis found no increased risk of mortality or graft failure associated with DLT compared to DDLT.

Heart transplantation in cardiac amyloidosis

"Cardiac amyloidosis" is the term commonly used to reflect the deposition of abnormal protein amyloid in the heart. This process can result from several different forms, most commonly from light-chain (AL) amyloidosis and transthyretin (ATTR) amyloidosis, which in turn can represent wild-type (ATTRwt) or genetic form. Regardless of the origin, cardiac involvement is usually associated with poor prognosis, especially in AL amyloidosis. Although several treatment options, including chemotherapy, exist for different forms of the disease, cardiac transplantation is increasingly considered. However, high mortality on the transplantation list, typical for patients with amyloidosis, and suboptimal post-transplant outcomes are major issues. We are reviewing the literature and summarizing pros and cons of listing patients with amyloidosis for cardiac or combine organ transplant, appropriate work-up, and intermediate and long-term outcomes. Both AL and ATTR amyloidosis are included in this review.

Amyloid Polyneuropathy and Myocardial Amyloidosis 10 Years after Domino Liver Transplantation from a Patient with a Transthyretin Ser50Arg Mutation

A 54-year-old man with polycystic liver disease received a domino liver transplantation (DLT) from a patient of hereditary ATTR amyloidosis with the transthyretin Ser50Arg mutation. Ten years after transplantation, he felt a slight numbness in his toes, and cardiac amyloidosis was simultaneously suspected upon a heart function evaluation. Biopsy specimens from the myocardium revealed transthyretin amyloidosis with the Ser50Arg mutation. Oral tafamidis therapy has inhibited the progression of neurological and cardiovascular symptoms this far. We herein report this first case of amyloid polyneuropathy and myocardial amyloidosis after DLT from hereditary ATTR amyloidosis with a transthyretin Ser50Arg mutation and discuss similar cases of other mutations.

Iatrogenic amyloid polyneuropathy after domino liver transplantation

Liver transplantation has been used in treatment of transthyretin amyloidosis, and some patients undergo domino liver transplantation (DLT) with explanted liver being transplanted to another patient with liver failure as the liver is otherwise usually functionally normal. Until end of 2015, there were 1154 DLT performed worldwide. DLT for transthyretin amyloidosis is associated with the risk of developing de novo systemic amyloidosis and amyloid neuropathy, and the risk may be greater with some non-Val30Met mutations. De novo amyloid neuropathy has been described in up to 23% of transplant recipients. Neuropathy may be preceded by asymptomatic amyloid deposition in various tissues and symptoms of neuropathy started after a median of 7 years following DLT (5.7 ± 3.2 years; range 2 mo to 10 years). Typical initial symptoms include neuropathic pain and sensory loss, while dysautonomia usually starts later. Progression of neuropathy may necessitate liver re-transplantation, and subsequent improvement of neuropathy has been reported in some patients. Explant allograft recipients need close monitoring for signs of systemic amyloidosis, neuropathy and dysautonomia as progressive symptoms may require re-transplantation.

Rapidly Progressive Transthyretin-Mediated Amyloidosis in a Domino Liver Transplant Recipient of a Ser23Asn Donor

Domino liver transplantation, in which the liver of a patient with transthyretin-mediated amyloidosis is transplanted into another patient, has been an established procedure performed at several centers across the world. The risk of developing systemic amyloidosis in transthyretin-mediated amyloidosis liver transplant recipients is a topic of ongoing investigation. We report a case of rapidly progressive transthyretin amyloidosis in a patient who received a liver from a donor with a rare Ser23Asn mutation. We advise exercising caution when considering domino liver transplantation in patients with this particular mutation.

Multimodality Imaging of Cardiac Transthyretin Amyloidosis 16 Years After a Domino Liver Transplantation

We report the case of a 62-year-old man hospitalized in May 2015 for symptomatic heart failure. His medical history included two liver transplantations. The first liver transplantation was performed in 1999 for a mixed alcoholic and hepatitis C-related cirrhosis and the patient received the liver of another patient with Val30Met transthyretin amyloidosis using the domino technique. In 2008, he complained of neuropathic pains and an iatrogenic-acquired transthyretin amyloidosis was diagnosed. On cardiac evaluation, amyloidosis was suspected. In March 2010, a second liver transplantation was performed with a deceased donor without complication. In May 2015, a first episode of symptomatic heart failure occurred and cardiac amyloidosis was investigated by a multimodality evaluation. Electrocardiogram, cardiac biomarkers, echocardiography, and cardiac MRI were in favor of the diagnosis of amyloidosis, whereas ^99m Tc-dicarboxypropane diphosphonate scintigraphy was not. Endomyocardial biopsy finally confirmed the positive diagnosis of iatrogenic-acquired cardiac amyloidosis. This case is, to the best of our knowledge, the first to report biopsy-proven cardiac amyloidosis induced by domino liver transplantation and progressing heart failure in spite of retransplantation. The diagnostic modalities are discussed. This case should alert physicians to the cardiac risk in domino liver transplanted patients.

The pathological and biochemical identification of possible seed-lesions of transmitted transthyretin amyloidosis after domino liver transplantation

The most serious issue in domino liver transplantation (DLT) using liver grafts from patients with transthyretin (TTR)‐related familial amyloid polyneuropathy (FAP) is the development of iatrogenic transmitted amyloidosis (de novo amyloidosis) in DLT‐recipients. However, little is known regarding the mechanisms of the initial stage of amyloid formation in these recipients. We detected initial lesions (possible seed‐lesions) of this iatrogenic amyloidosis in two recipients following liver grafting from FAP patients. Patient 1 underwent DLT at age 65 from an FAP patient with a Val30Met TTR variant and patient 2 received DLT from an FAP patient with a Val30Leu TTR variant at age 32. Patient 2 was started on diflunisal administration from 4 years after DLT. While neither patient had symptoms of FAP, small amyloid deposits were detected on the gastroduodenal mucosae 14 months and 12 years after DLT in patient 1 and patient 2, respectively. The amyloid was analyzed using a laser microdissection system and tandem mass spectrometry. Biochemical analysis indicated that the amyloid was composed mostly of variant TTR produced from the transplanted liver in both patients. In patient 1, wild‐type TTR amyloid was detectable in the duodenal mucosa obtained 2 years after DLT. This is the first study to successfully capture the pathological and biochemical features of initial‐stage amyloid lesions in DLT recipients. The findings clearly indicate that amyloid deposition can start by deposition of variant TTR followed by deposition of wild‐type TTR, and blocking of amyloid seed formation from variant TTR may be a key to prevent or delay the development of DLT‐associated amyloidosis.

Liver retransplantation in patients with acquired familial amyloid polyneuropathy: a Portuguese center experience

In 1995 Furtado et al performed the first domino transplantation using a donor liver with familial amyloid polyneuropathy (FAP), thereby increasing the pool of donors. Our experience showed that the onset of FAP symptoms occurs earlier in some patients. Patients with FAP acquired by transplantation are candidates for liver retransplantation to minimize the progression of symptoms. Liver retransplantation is considered to be a high-risk procedure and has lower survival compared with the first transplantation. We evaluated the risk of liver retransplantation in patients with acquired FAP. We did a retrospective analysis of these patients based on the records of perioperative data. From 1995 to 2004 we carried out 81 domino transplantations, of which 10 were submitted to liver retransplantation because of acquired FAP. The better outcomes in this group lead us to think that the liver retransplantation in patients with acquired FAP is not associated with the same risks of liver retransplantation in candidates with graft failure.

Evolving landscape in the management of transthyretin amyloidosis

Transthyretin (TTR) amyloidosis (ATTR amyloidosis) is a multisystemic, multigenotypic disease resulting from deposition of insoluble ATTR amyloid fibrils in various organs and tissues. Although considered rare, the prevalence of this serious disease is likely underestimated because symptoms can be non-specific and diagnosis largely relies on amyloid detection in tissue biopsies. Treatment is guided by which tissues/organs are involved, although therapeutic options are limited for patients with late-stage disease. Indeed, enthusiasm for liver transplantation for familial ATTR amyloidosis with polyneuropathy was dampened by poor outcomes among patients with significant neurological deficits or cardiac involvement. Hence, there remains an unmet medical need for new therapies. The TTR stabilizers tafamidis and diflunisal slow disease progression in some patients with ATTR amyloidosis with polyneuropathy, and the postulated synergistic effect of doxycycline and tauroursodeoxycholic acid on dissolution of amyloid is under investigation. Another therapeutic approach is to reduce production of the amyloidogenic protein, TTR. Plasma TTR concentration can be significantly reduced with ISIS-TTR(Rx), an investigational antisense oligonucleotide-based drug, or with patisiran and revusiran, which are investigational RNA interference-based therapeutics that target the liver. The evolving treatment landscape for ATTR amyloidosis brings hope for further improvements in clinical outcomes for patients with this debilitating disease.

Evaluation of operative risk in de novo familial amyloid polyneuropathy retransplantation

Familial amyloid polyneuropathy (FAP) is the most common hereditary amyloidosis, characterized by progressive peripheral sensory and motor neuropathy. The livers of patients with FAP are used in domino liver transplantation in selected cases to increase the number of grafts available. In our department 10 patients underwent liver retransplantation (ReLTx) in the absence of liver dysfunction by de novo FAP after domino liver transplantation. Our aim was to compare the differences in the consumption of blood products and intraoperative hemodynamic support among patients with FAP undergoing liver transplantation (LTx) and patients with de novo FAP undergoing ReLTx in the same time frame. The anesthetic records of all patients who underwent LTx for FAP and ReLTx for de novo FAP were analyzed, from January 2009 to May 2014. Patients were divided into 2 groups: group 1 patients with FAP, and group 2 patients with de novo FAP. Statistical differences in the value of preoperative creatinine were found. Hemoglobin levels, preoperative international normalized ratio (INR), use of blood products, aminergic support, and surgical time showed no statistical difference. Major bleeding rates would be expected in patients undergoing ReLTx. Changes in renal function, chronic immunosuppressive therapy, and age may contribute to the increase in intraoperative complications. We did not find statistically significant differences, leading us to the conclusion that de novo FAP does not seem to be a predictor of perioperative risk.

Liver transplantation in transthyretin amyloidosis: issues and challenges

Hereditary transthyretin amyloidosis (ATTR) is a rare worldwide autosomal dominant disease caused by the systemic deposition of an amyloidogenic variant of transthyretin (TTR), which is usually derived from a single amino acid substitution in the TTR gene. More than 100 mutations have been described, with V30M being the most prevalent. Each variant has a different involvement, although peripheral neuropathy and cardiomyopathy are the most common. Orthotopic liver transplantation (OLT) was implemented as the inaugural disease-modifying therapy because the liver produces the circulating unstable TTR. In this review, we focus on the results and long-term outcomes of OLT for ATTR after more than 2063 procedures and 23 years of experience. After successful OLT, neuropathy and organ impairment are not usually reversed, and in some cases, the disease progresses. The overall 5-year survival rate is approximately 100% for V30M patients and 59% for non-ATTR V30M patients. Cardiac-related death and septicemia are the main causes of mortality. Lower survival is related to malnutrition, a longer duration of disease, cardiomyopathy, and a later onset (particularly for males). Deposits, which are composed of a mixture of truncated and full-length TTR (type A) fibrils, have been associated with posttransplant myocardial dysfunction. A higher incidence of early hepatic artery thrombosis of the graft has also been documented for these patients. Liver-kidney/heart transplantation is an alternative for patients with advanced renal disease or heart failure. The sequential procedure, in which ATTR livers are reused in patients with liver disease, reveals that neuropathy in the recipient may appear as soon as 6 years after OLT, and ATTR deposits may appear even earlier. Long-term results of trials with amyloid protein stabilizers or disrupters, silencing RNA, and antisense oligonucleotides will highlight the value and limitations of liver transplantation.

Systemic amyloidoses: what an internist should know

Systemic amyloidoses are rare, complex diseases caused by misfolding of autologous proteins. Although these diseases are fatal, effective treatments exist that can alter their natural history, provided that they are started before irreversible organ damage has occurred. The cornerstones of the management of systemic amyloidoses are early diagnosis, accurate typing, appropriate risk-adapted therapy, tight follow-up, and effective supportive treatment. Internists play a key role in suspecting the disease, thus allowing early diagnosis, starting the diagnostic workup and selecting patients that should be referred to specialized centers, judiciously titrating supportive measures, and following patients throughout the course of the disease. Here we review the pathogenesis, diagnosis and treatment of the most common forms of systemic amyloidoses.

Reversibility of acquired amyloid polyneuropathy after liver retransplantation

Domino liver transplantation (DLT) has become an accepted procedure designed to address problems with organ limited supply. However, cases of acquired amyloid neuropathy are increasingly being recognized following this procedure. Until now, only one patient had undergone liver retransplantation and follow-up findings were not reported. We describe the case of a 72-year-old patient with partial recovery from acquired amyloid neuropathy following retransplantation with a deceased donor 7 years after DLT performed for end-stage liver disease. His clinical and paraclinical improvement is described, and the impact of this case on the indication for a domino procedure and the challenges linked to retransplantation are discussed.

Amyloid fibrils containing fragmented ATTR may be the standard fibril composition in ATTR amyloidosis

Abstract The clinical phenotype of familial ATTR amyloidosis depends to some extent on the particular mutation, but differences exist also within mutations. We have previously described that two types of amyloid fibril compositions exist among Swedish ATTRV30M amyloidosis patients, one consisting of a mixture of intact and fragmented ATTR (type A) and one consisting of mainly intact ATTR (type B). The fibril types are correlated to phenotypic differences. Patients with ATTR fragments have a late onset and develop cardiomyopathy, while patients without fragments have an early onset and less myocardial involvement. The present study aimed to determine whether this correlation between fibril type and phenotype is valid for familial ATTR amyloidosis in general. Cardiac or adipose tissues from 63 patients carrying 29 different TTR non-V30M mutations as well as 13 Japanese ATTRV30M patients were examined. Fibril type was determined by western blotting and compared to the patients' age of onset and degree of cardiomyopathy. All ATTR non-V30M patients had a fibril composition with ATTR fragments, except two ATTRY114C patients. No clear conclusions could be drawn about a phenotype to fibril type correlation among ATTR non-V30M patients. In contrast, Japanese ATTRV30M patients showed a similar correlation as previously described for Swedish ATTRV30M patients. This study shows that a fibril composition with fragmented ATTR is very common in ATTR amyloidosis, and suggests that fibrils composed of only full-length ATTR is an exception found only in a subset of patients.

Familial amyloid polyneuropathy

Familial amyloid polyneuropathy (FAP; also known as familiar amyloidosis and hereditary amyloidosis) is an autosomal dominant inherited disease due to mutations of the transthyretin (TTR) gene coding for the corresponding protein, consisting of 127 amino acids. The gene is located on chromosome 18q. More than 100 different mutations are known. Other mutant precursor proteins produced in the liver, such as apolipoprotein I and II, lysozyme and fibrinogen Aα, may be of etiological importance as well. Amyloidogenic mutations of the TTR gene lead to decreased stability of the corresponding protein and subsequently to extracellular deposition of amyloid in several tissues (peripheral and autonomic nerves, walls of the gastrointestinal tract, heart, etc.). The Val30Met mutation is the most prevalent cause of FAP worldwide. There are endemic regions in Portugal, Sweden and Japan. The onset of symptoms is usually between 25 and 35 years of age, but late-onset families are also known. The most common clinical symptoms are polyneuropathy of the lower limbs, rhythmological disturbances and diarrhea/obstipation. TTR amyloid is predominantly produced in the liver; only as few as 5% are synthesized in the retina and choroid plexus. Therefore, liver transplantation has become widely accepted as the ultimate curative treatment of this disease in order to prevent the ultimately fatal outcome and ameliorate disabling symptoms. Because of shortage of donor grafts, livers of FAP patients are used for domino liver transplantation. Last year, a new therapeutic option was approved by the European Medical Authority (EMA) for therapy of early-stage FAP. The first results of a multicenter-controlled trial have been published and show a benefit in patients with an early stage of disease regarding neurological symptoms as well as modified BMI. There are several other pharmacologic approaches that have been reported in the last years which may lead to stabilization of the TTR tetramer. Therefore, this might be the beginning of new therapeutic options with pharmacological therapies in patients with FAP.

Evaluation of domino liver transplantations in Germany

A retrospective multicenter study has been conducted to evaluate domino liver transplantations (DLTs) in Germany. The study provides insight into survival and features having an impact on the assessment of neuropathy after DLT. In addition, a neurologic follow-up program with a scheme to estimate the likelihood of de novo amyloidosis is presented. A series of 61 DLTs at seven transplant centers in Germany was enrolled. The mean age of domino recipients at the time of transplantation was 58 years, 46 of them being men, and 15 being women. The median follow-up was 46 months. The overall 1-, 3-, and 5-year survival of domino recipients was 81.6%, 70.8% and 68.8%, respectively. Causes of death were primarily not related to familial amyloidosis. The main indication of DLT was hepatocellular carcinoma. Two of the reported domino recipients developed symptoms and signs of de novo amyloidosis within 10 years after transplantation. A total of 30 domino graft recipients (49.18%) presented with diabetes post transplantation. In conclusion, an advanced follow-up program is crucial to evaluate the risk of transmitting familial amyloidosis by DLT and to establish more strict selection criteria for domino recipients.

The first Caucasian patient with p.Val122Ile mutated-transthyretin cardiac amyloidosis treated with isolated heart transplantation

Effective treatments for mutated transthyretin (TTR)-related cardiac amyloidosis are limited. Heart transplantation or combined liver-heart transplantation are the most successful options, although results rely on underline mechanism and systemic nature of the disease. In this report, we present the first case of a Caucasian patient with the p.Val122Ile mutated TTR-related cardiac amyloidosis treated with heart transplantation due to this gene mutation frequent in Afro-Americans with a prevalent isolated heart involvement. The choice of isolated heart transplantation instead of combined heart and liver transplantations was based on (1) severe and progressive cardiac disease, (2) evidence of a gene mutation generally associated with isolated cardiac disease and (3) absence of relevant extra-cardiac involvement (with the possible exception of mild peripheral neuropathy). In any case, the very short post-transplant observation period of 10 months does not allow any conclusions on the long-term course of the presented strategy. Finally, it is the first European Caucasian family with the p.Val122Ile TTR mutation that has been described. Till now, very few Caucasian cases of p.Val122Ile mutated TTR-related cardiac amyloidosis have been reported. The patient and some members of his family also had mild peripheral neuropathy suggesting a regional phenotypic heterogeneity of European Caucasian TTR p.Val122Ile.

Focus on autonomic dysfunction in familial amyloidotic polyneuropathy (FAP)

It is well known that autonomic dysfunction in familial amyloidotic polyneuropathy (FAP) is the most serious problem, because it restricts the daily life of these patients. The detail mechanisms of the onset are not well understood in FAP and domino liver transplantation-induced amyloid neuropathy. As autonomic disturbances play an important role in the symptomatology of FAP, further studies of autonomic dysfunction in these patients may lead the pathogenesis of FAP. Autonomic dysfunction is often observed before sensory and motor nerve dysfunction in FAP. This can be attributed to the morphological characteristics of the nerves. Unmyelinated, small myelinated, and large myelinated fibers tend to become impaired in that order. Although the reasons of susceptibility to amyloid infiltration and injury are not known, studies of autopsied FAP patients have revealed heavy infiltration of amyloid in autonomic ganglions. Moreover, spinal ganglion and posterior loot of the spine had severe amyloid deposits than did the anterior root of the spine or the motor nerves. It is well known that autonomic dysfunction is the most serious problem, because it restricts the daily life of FAP patients. However, we have four major questions about autonomic dysfunction in clinical. In this manuscript, we discuss about the answers of these questions.

Domino liver transplantation: indications, techniques, and outcomes

The long-term shortage of livers available for transplantation has spurred the development of many strategies to bolster the donor organ supply. One particularly innovative strategy is domino liver transplantation in which a select group of liver transplant recipients can donate their explanted native livers for use as liver grafts in other patients. Several hereditary metabolic diseases (such as familial amyloid polyneuropathy, maple syrup urine disease, and familial hypercholesterolemia) are caused by aberrant or deficient protein production in the liver, and these conditions can be cured with an orthotopic liver transplant. Although their native livers eventually caused severe systemic disease in these patients, these livers are otherwise structurally and functionally normal, and they have been used successfully in domino liver transplants for the past 15 years. This article will review the indications for donating or receiving a domino liver transplant, the surgical techniques necessary to perform these transplants, as well as the recently revealed long-term outcomes and risks of domino transplantation.

Domino versus deceased donor liver transplantation: association with early graft function and perioperative bleeding

This study sought to evaluate the potential impact of domino liver transplantation (DLT) on initial graft function and early postoperative outcome in patients with cirrhosis in a Portuguese liver transplantation center. A retrospective comparative analysis was performed between 77 domino recipients (from familial amyloidotic polyneuropathy donors) and 91 deceased donor recipients, all submitted to primary elective whole liver transplantation, using the piggyback technique, in a 42-month period. Outcome parameters included graft dysfunction (defined as either primary nonfunction or initial poor function, according to the Ploeg-Maring criteria) and Clavien II-IV complications in the first postoperative week. Domino and deceased donor recipients had similar preoperative severity indices (Child-Pugh classification and Model for End-Stage Liver Disease score) and immediate postoperative severity scores (APACHE II [Acute Physiology and Chronic Health Evaluation II] and SAPS II [Simplified Acute Physiology Score II]). In DLT, donors were younger, cold ischemia time was shorter, and intraoperative transfusion requirements of packed red blood cells and fresh-frozen plasma were significantly lower. Graft dysfunction incidence was 3.4-fold lower in DLT: 5.2% (only 4 cases of initial poor function) versus 18.0% (1 primary nonfunction and 15 cases of initial poor function), P = 0.010. Postoperative bleeding was the most frequent early Clavien II-IV complication (n = 29, 17.3%), with an incidence 2.2-fold lower in domino recipients. A statistically significant difference was not found in the other analyzed Clavien II-IV complications, intensive care unit stay, mechanical ventilation time, intensive care unit mortality, and 1-year survival rate. In conclusion, in this study the younger donors and shorter ischemic time associated with DLT may provide a protective role in regards to graft dysfunction and perioperative bleeding, which are 2 important determinants of early morbidity after liver transplantation.

Risk of transmission of systemic transthyretin amyloidosis after domino liver transplantation

Recent reports of the transmission of systemic transthyretin (TTR) amyloidosis after domino liver transplantation (DLT) using grafts from patients with familial amyloid polyneuropathy (FAP) have raised concerns about the procedure. The aim of this study was to evaluate the transmission incidence of systemic TTR amyloidosis after DLT with a complete clinical, neurological, and pathological assessment. At our institution, DLT has been performed 31 times with livers from patients with FAP. Seventeen of the 19 patients still alive in 2008 agreed to enter the study. This cross-sectional study of this cohort of patients included clinical assessments, rectal biopsy, and electroneuromyography (as well as sural nerve biopsy when it was indicated). The mean follow-up at the time of the study was 62.6 ± 2.9 months. Clinically, 3 patients complained of weak dysesthesia. When a focused study was performed, 8 patients reported some kind of neurological and/or gastrointestinal disturbance. Six of the rectal biopsy samples showed amyloid deposits (TTR-positive). Electromyography (EMG) showed signs of mild sensorimotor neuropathy in 3 cases and moderate to severe sensorimotor neuropathy in 1 case. Only 2 of the 4 patients with EMG signs of polyneuropathy showed amyloid deposits in their rectal biopsy samples. Sural nerve biopsy revealed amyloid deposits (TTR-positive) in all 4 patients with EMG signs of polyneuropathy. Two patients with normal EMG findings had TTR-positive amyloid deposits in their sural nerve biopsy samples. In conclusion, de novo systemic amyloidosis after DLT may be more frequent and appear earlier than was initially thought. In our opinion, however, the graft shortage still justifies DLT in selected patients, despite the risk of de novo systemic amyloidosis. Sural nerve biopsy with EMG and clinical correlation is mandatory for confirming the disease. Indeed, other causes of neuropathy should be excluded.