Livers from patients with apolipoprotein A-I amyloidosis are not suitable as "domino" donors

"No-donor" liver transplantation

Liver transplantation is hindered by organ shortage. The potential way to relieve this issue is to expand the donor pool via extending the donor criteria and make full use of all available grafts. The concept of "no-donor" liver transplantation allows grafts to be recovered from other liver recipients. This review summarizes the current clinical practice of "no-donor" liver transplantation, focusing on the experiences of Chinese transplant teams. Domino liver transplantation was introduced by Furtado in 1995 and implemented later in 2013 in China, and novel donor indications including some essential-to-treat inherited metabolic liver-based diseases have emerged. The concept of cross-auxiliary domino liver transplantation brings a further expansion of the domino liver graft pool, and the first pair of liver transplantation performed "rigorously without donation" was accomplished in our center in 2018. Our experience with this original transplantation procedure is hereby reviewed. In order to further promote and make successful "no-donor" liver transplantation, close co-operation between researchers, surgeons, physicians, organ procurement organizations, as well as ethical committees is required.

Morphological findings in different subtypes of hepatic amyloid

The classic findings have been well described for light-chain amyloid involving the liver. In addition to light chain, however, many additional proteins are now known to be amyloidogenic and can involve the liver. A total of 58 surgical pathology specimens with amyloid deposits were analyzed for patterns of amyloid deposition, including amyloid from light chain lambda (N = 17), light chain kappa (N = 15), transthyretin (N = 15), serum amyloid A (N = 4), apolipoprotein A1 (N = 4), fibrinogen alpha (N = 2), LECT2 (N = 1). Amyloid deposits predominately targeted the liver vasculature, including the walls of the hepatic arteries, portal veins, and sinusoids. While there was overlap, light chain amyloid predominately involved the sinusoids, while transthyretin amyloid predominately targeted the hepatic arteries, especially the larger ones in the hilum and larger portal tracts. Serum amyloid A formed nodular deposits that started in the portal vasculature but then extended into the portal tract stroma, leading to large, bulbous, portal-based amyloid deposits. Apolipoprotein A amyloid also formed large portal-based nodules. Fibrinogen was mild and subtle on H&E and predominately affected portal veins. Amyloid deposits in hilar nerves were prominent with amyloid light chain, transthyretin, and apolipoprotein A1. In conclusion, the histology of hepatic amyloid is diverse and shows several distinct clusters of findings that can aide in recognition in surgical pathology specimens.

Liver transplantation using grafts with rare metabolic disorders

Metabolic diseases that involve the liver represent a heterogeneous group of disorders. Apart from the metabolic defect, the subject's liver functions may be normal. With the increasing need for organs, livers from donors with metabolic diseases other than familial amyloid polyneuropathy might be possibly used for transplantation. However, whether such livers qualify as grafts and how they might impact recipient outcome are still unanswered questions. This review of the literature summarizes current experience in the use of such grafts in the context of cadaveric, domino, and living-related liver transplantation.

Amyloid diseases of the heart: current and future therapies

Amyloid diseases in man are caused by as many as 23 different pre-cursor proteins already described. Cardiologists predominantly encounter three main types of amyloidosis that affect the heart: light chain (AL) amyloidosis, senile systemic amyloidosis (SSA) and hereditary amyloidosis, most commonly caused by a mutant form of transthyretin. In the third world, secondary amyloid (AA) is more prevalent, due to chronic infections and inadequately treated inflammatory conditions. Much less common, are the non-transthyretin variants, including mutations of fibrinogen, the apolipoproteins apoA1 and apoA2 and gelsolin. These rarer types do not usually cause significant cardiac compromise. Occurring worldwide, later in life and of less clinical significance, isolated atrial amyloid (IAA) also involves the heart. Heart involvement by amyloid often has devastating consequences. Clinical outcome depends on amyloid type, the extent of systemic involvement and the treatment options available. An exact determination of amyloid type is critical to appropriate therapy. In this review we describe the different approaches required to treat this spectrum of amyloid cardiomyopathies.

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.

Clinical aspects of systemic amyloid diseases

Amyloidosis is a protein misfolding disorder in which soluble proteins aggregate as insoluble amyloid fibrils. Protein aggregates and amyloid fibrils cause functional and structural organ damage respectively. To date, at least 24 different proteins have been recognized as causative agents of amyloid diseases, localized or systemic. The two most common forms of systemic amyloidosis are light-chain (AL) amyloidosis and reactive AA amyloidosis due to chronic inflammatory diseases. beta(2)-microglobulin amyloidosis is a common complication associated with long-term hemodialysis. Hereditary systemic amyloidoses are a group of autosomal dominant disorders caused by mutations in the genes of several plasma proteins. Heterogeneity in clinical presentation, pattern of amyloid-related organ toxicity and rate of disease progression is observed among systemic amyloidoses. In particular, beta(2)-microglobulin presents unique clinical features compared to the other systemic forms. The phenotypic features of hereditary systemic amyloidoses may instead overlap those of the two more common forms of acquired amyloidoses mentioned above and therefore a correct diagnosis can not rely only on clinical grounds. Unequivocal identification of the deposited protein is essential in order to avoid misdiagnosis and inappropriate treatment. Amyloid deposits can be reabsorbed and organ dysfunction reversed if the concentration of the amyloidogenic protein is reduced or zeroed. At present, the most effective approach to treatment of the systemic amyloidoses involves shutting down, or substantially reducing the synthesis of the amyloid precursor, or, as in the case of beta(2)-microglobulin, promoting its clearance.

Metabolic storage diseases: amyloidosis

This article provides an overview of the current concepts in pathogenesis, epidemiology, clinical significance, and treatment options for amyloidosis. Emphasis is given to hepatic amyloidosis, which ranges from a clinically insignificant histologic curiosity to a harbinger of widespread disease accompanied by a poor prognosis. Clinical characteristics and clues to the diagnosis are discussed as well as the importance of histologic confirmation and the controversy surrounding liver biopsy.

Microscopic colitis: an update

Microscopic colitis is an increasingly common cause of chronic diarrhea, and often causes abdominal pain and weight loss. The colonic mucosa appears normal or nearly normal endoscopically, and the diagnosis is made in the appropriate clinical setting when there is intraepithelial lymphocytosis and a mixed lamina propria inflammatory infiltrate. The 2 subtypes, collagenous and lymphocytic colitis, are similar clinically and histologically, and are distinguished by the presence or absence of a thickened subepithelial collagen band. Many potential pathophysiologic mechanisms have been proposed, but no convincing unifying mechanism has been identified. There are many anecdotal reports on treatment, but few controlled trials have been performed in these patients, although a systematic approach to therapy often leads to the satisfactory control of symptoms.

Apoa1 related amyloidosis: a case report and literature review

OBJECTIVES

Amyloidosis results from local or systemic extracellular deposition of insoluble protein fibrils and is associated with certain rare mutations in APOA1 encoding apolipoprotein (apo) A-I.

DESIGN AND METHODS

In a patient with renal-predominant amyloidosis with neuropathy, we found the APOA1 G26R mutation.

CONCLUSIONS

While the spectrum of APOA1 mutations provides no particular mechanistic insights, molecular diagnosis may still be important due to clinical differences between amyloidosis resulting from mutation in APOA1 vs. other genes.

Microscopic colitis: a review

Microscopic colitis is a relatively common cause of chronic watery diarrhea, often accompanied by abdominal pain and weight loss. The colonic mucosa appears normal grossly, and the diagnosis is made when there is an intraepithelial lymphocytosis and a mixed inflammatory infiltrate in the lamina propria. The two main subtypes, collagenous and lymphocytic colitis, are similar clinically and histologically, distinguished by the presence or absence of a thickened subepithelial collagen band. Many potential pathophysiological mechanisms have been described, although none have been conclusively proved. There is a paucity of randomized treatment trials in these patients, although a rational approach to therapy often leads to satisfactory control of symptoms.