Yo-ichi Takei

Progressive Wild‐Type Transthyretin Deposition after Liver Transplantation Preferentially Occurs onto Myocardium in FAP Patients

To elucidate whether progressive wild‐type transthyretin (TTR) deposition can actually occur after liver transplantation (LT), amyloid fibrils were investigated in two familial amyloid polyneuropathy patients with TTR Val30Leu variant, who died 1 year after LT. Amyloid fibrils were extracted from cardiac muscles, sciatic nerves and kidney, which were investigated by the immunoprecipitation‐mass spectrometry method and liquid chromatography‐ion trap mass spectrometry analysis. The ratio of wild‐type to variant TTR in cardiac muscle was approximately 5:5 before LT, but greatly increased to about 9:1 after transplantation. The ratios in sciatic nerves and kidney obtained at autopsy were approximately 5:5. Wild‐type TTR was undetectable in kidney amyloid obtained before LT. Our results indicate that paradoxical wild‐type TTR deposition after LT can preferentially occur in myocardium, leading to fatal cardiac dysfunction, but it is quite likely that this phenomenon can also occur in other visceral organs.

Type II (adult onset) citrullinaemia: clinical pictures and the therapeutic effect of liver transplantation

OBJECTIVE Adult onset type II citrullinemia is an inherited disorder of amino acid metabolism caused by a deficiency of liver specific argininosuccinate synthetase activity. Most of the patients with this disease were reported in Japan and therefore, this disease has not been well recognised outside this country. The detailed clinical pictures of the patients with type II citrullinaemia are reported and their outcomes after liver transplantation referred to. METHODS Ten patients with this disease were evaluated. Seven of them underwent liver transplants using a graft obtained from a healthy family member. RESULTS There were six men and four women; the age of onset of encephalopathy ranged from 17 to 51 years. The initial symptom in nine patients was sudden onset disturbance of consciousness, and one patient had long been regarded as having a chronic progressive psychotic illness. High concentrations of plasma citrulline and ammonia were commonly seen on admission. Although brain CT or MRI lacked any consistent findings, the EEG was abnormal in all patients, showing diffuse slow waves. Additionally, in five patients chronic pancreatitis preceded the onset of encephalopathy. After liver transplantation the metabolic abnormalities, including abnormal plasma concentrations of citrulline and ammonia, were immediately corrected and all neuropsychic symptoms soon disappeared, except for impaired cognitive function in one patient. Six out of these seven patients returned to their previous social lives, including work. CONCLUSIONS The clinical concept of adult onset type II citrullinaemia coincides well with the range of hepatic encephalopathy, and liver transplantation is a very promising therapeutic approach.

Citrin deficiency as a cause of chronic liver disorder mimicking non-alcoholic fatty liver disease.

BACKGROUND/AIMS Citrin deficiency caused by SLC25A13 gene mutations develops into adult-onset type II citrullinemia (CTLN2) and may be accompanied with hepatic steatosis and steatohepatitis. As its clinical features remain unclear, we aimed to explore the characteristics of fatty liver disease associated with citrin deficiency. METHODS The prevalence of hepatic steatosis in 19 CTLN2 patients was examined, and clinical features were compared with those of non-alcoholic fatty liver disease (NAFLD) patients without known SLC25A13 gene mutations. RESULTS Seventeen (89%) CTLN2 patients had steatosis, and 4 (21%) had been diagnosed as having NAFLD before appearance of neuropsychological symptoms. One patient had steatohepatitis. Citrin deficiency-associated fatty livers showed a considerably lower prevalence of accompanying obesity and metabolic syndrome, higher prevalence of history of pancreatitis, and higher serum levels of pancreatic secretory trypsin inhibitor (PSTI) than fatty livers without the mutations. Receiver operating characteristic curve analyses revealed that a body mass index < 20kg/m(2) and serum PSTI>29ng/mL were associated with citrin deficiency. CONCLUSIONS Patients presenting with non-alcoholic fatty liver unrelated to obesity and metabolic syndrome might have citrin deficiency, and serum PSTI may be a useful indicator for distinguishing this from conventional NAFLD.

Partial-Liver Transplantation To Treat Familial Amyloid Polyneuropathy: Follow-up of 11 Patients

Familial amyloid polyneuropathy (FAP) is characterized by progressive polyneuropathy and autonomic failure (1). Three large foci of patients with this disease are known to exist in Portugal, Sweden, and Japan (2). In FAP, the precursor of amyloid fibril is variant transthyretin in serum (3). Because the liver produces the greater part of the transthyretin in serum (4), it has been assumed that the replacement of a patients liver that is expressing an abnormal transthyretin gene might stop the production of the serum amyloid precursor in FAP. Since the first successful liver transplantation for a patient with FAP was performed in Sweden in 1990 (5, 6), this challenging operation has been widely accepted (7-11). In Japan, full-liver transplantation is uncommon because brain death is not recognized as a definition of death. As an alternative, we performed partial-liver transplantation for patients with FAP using grafts from living donors (12). We report on the outcomes of 11 patients with FAP who underwent this operation at our institution. Methods From November 1993 to November 1998, 11 patients with FAP who had a transthyretin gene mutation (one amino acid substitution of methionine for valine at position 30, shown by DNA testing [13]) underwent partial-liver transplantation from living donors. The patients, who were 25 to 47 years of age, had had symptoms of FAP for 6 months to 10 years. All 11 donors were shown to be free of an abnormal transthyretin gene; 4 donors were spouses, and the other 7 were brothers, sisters, or parents of the patient. The operations were performed after approval was obtained from the local ethics committee. The details of the operative technique have been reported elsewhere (14, 15). During the operation, the patients entire liver was removed. The left lobe, including the middle hepatic vein, was harvested from the living donor and was transplanted orthotopically. Either corticosteroid and tacrolimus or corticosteroid, cyclosporine, and azathioprine were used as immunosuppression agents. The postoperative follow-up for the patients ranged from 3 to 64 months. During the study period, 20 patients with FAP did not have transplantation because of advanced disease or poor clinical condition. Before surgery, all patients underwent thorough general physical and neurologic evaluations. Routine laboratory data, including blood cell counts, serum protein analyses, and liver and renal function tests, were examined. Nerve conduction studies were performed on the right ulnar and tibial nerves. Left sural nerve biopsies were performed, and myelinated fiber lesions were quantitatively examined (16). After surgery, neurologic findings were regularly examined by the same neurologist once a month. Serial measurements of nerve conduction velocities and body weight were performed every 6 months. During the final preoperative examinations, patients were clinically staged according to the criteria proposed by Coutinho and colleagues (17): group 1, patients with gastrointestinal autonomic disorders without apparent polyneuropathy (FAP stage 0); group 2, patients with polyneuropathy localized to the lower limbs (FAP stage I); group 3, patients with polyneuropathy involving both upper and lower limbs (FAP stage II). Results The results are summarized in the Table. Table. Clinical and Laboratory Data and Patient Outcomes Group 1 Severe nausea and vomiting were the initial symptoms for patients 1, 2, and 3 and resulted in rapid weight loss (patient 1, 10 kg in 9 months; patient 2, 7 kg in 6 months; patient 3, 5 kg in 3 months). These patients also had a history of chronic constipation but no other autonomic symptoms. Routine laboratory data and upper- and lower-limb nerve conduction velocities were normal. Sural nerve biopsy specimens revealed small deposits of amyloid, mainly on the epineurium, in all three patients. Patients 1 and 2 had slightly decreased density of myelinated fibers and patient 3 had moderately decreased density, showing more selective involvement of small myelinated fibers (18) (Figure, part A). All three patients had been ill less than 1 year before transplantation. After surgery, the nausea and vomiting subsided and appetite returned within 3 months for all patients in group 1. At last follow-up, they had no polyneuropathy and no deterioration of nerve conduction velocities. Figure. Myelinated fiber lesions in sural nerve biopsy specimens. A. B. C. Group 2 The four patients in group 2 (patients 4, 5, 6, and 7) had polyneuropathy, which involved only the lower limbs, and autonomic disorders, such as orthostatic hypotension, alternating constipation and diarrhea, and dysuria. However, they did not experience any serious physical disabilities. Laboratory data were normal for all patients, except for slightly decreased creatinine clearance in patients 4 and 7. All patients had normal upper-limb nerve conduction velocities, but patient 7 had below-normal velocity in the tibial nerve. Sural nerve biopsies for patient 4, whose amyloid deposition pattern resembled that of patients in group 1, showed a slight reduction in myelinated fiber density. The other three patients in group 2 showed significant amounts of amyloid deposition in the endoneurium and a greatly reduced density of myelinated fibers (Figure, part B). Patients in group 2 had been ill 1 to 4 years before transplantation. Polyneuropathy and autonomic symptoms gradually improved postoperatively in all patients; leg paresthesia and abnormal bowel function improved within 1 year. Patients 5 and 7, who had longer postoperative courses, showed improvement in leg strength. Nerve conduction velocities did not deteriorate and actually returned to normal in 3 of the 4 patients. Group 3 Patients 8, 9, 10, and 11 were disabled by sensorimotor neuropathy and also had various autonomic dysfunctions. Patient 8 could walk unaided, whereas patients 9, 10, and 11 frequently used wheelchairs. Routine laboratory data showed low serum albumin levels in patients 9, 10, and 11, and creatinine clearance was significantly decreased in all four patients. Nerve conduction velocities were abnormal in the lower limbs or the upper limbs in patients 8 and 9 and were not detectable in the lower limbs of patients 10 and 11. Heavy amyloid deposits and marked reduction of myelinated fiber density were observed in the sural nerve biopsy specimens of patients 8 and 9; myelinated fibers were almost completely lost in patients 10 and 11 (Figure, part C). Patients in group 3 had been ill 4 to 10 years before transplantation. After transplantation, patient 8 gradually improved. In patient 9, polyneuritic symptoms progressed; she is now confined to a wheelchair. The postoperative course of patient 10 was complicated by the Stokes-Adams syndrome, bacterial pneumonia, and sepsis. When she was discharged 10 months after transplantation, her neurologic state was worse than it was before surgery. She died 21 months after transplantation. Patient 11 developed rapidly progressive renal dysfunction soon after operation and died on the 84th postoperative day. Discussion By May 1999, liver transplantations had been performed on 368 patients with FAP in 16 countries (19). Several follow-up studies (7-12) have shown beneficial therapeutic effects, but 78 of the 368 patients were reported to have died after surgery, mainly secondary to infection and cardiac disorders (19). Suhr and colleagues (11) reported that a modified body mass index and duration of illness, especially gastrointestinal illness, were reliable indicators of the prognosis after liver transplantation in patients with FAP. During the past 5 years, we have performed partial-liver transplantation in 11 patients with FAP. The patients in groups 1 and 2 recovered from the operation; at transplantation, they had had FAP for 4 years or less. However, the patients in group 3, especially those who had been ill for 6 years or more, had unfavorable postoperative outcomes. These results suggest that severity of polyneuropathy and duration of illness are associated with liver transplantation outcomes for patients with FAP. Serum levels of urea nitrogen and creatinine did not correspond with the severity of FAP symptoms or the duration of illness. No significant association between a modified body mass index and outcome was observed in 9 of 11 patients (data not shown). However, all 4 patients with greatly decreased creatinine clearance had advanced stages of FAP, and 3 of these 4 had longer histories of the disease and unfavorable outcomes after transplantation. Tibial nerve conduction velocities were also significantly delayed or undetectable in these patients. In addition, the severity of sural nerve fiber loss clearly reflected the duration of illness and the patients postoperative prognosis. Patients 1 to 4, who had myelinated fiber populations greater than 2500, had shorter histories of FAP (<2 years) and had excellent clinical outcomes after liver transplantation. Patients 5 to 9, who had myelinated fiber populations of 1000 to 2500, had 4- to 6-year histories of illness, and the severity of renal impairment seemed to be a crucial factor in their postoperative prognosis. Patients 10 and 11, who had myelinated fiber populations less than 1000, had longer clinical histories (>6 years) and experienced unfavorable outcomes after transplantation. In conclusion, patients in our series who had an early stage of FAP did well after liver transplantation, whereas those at advanced stages had adverse postoperative results, presumably because of serious dysfunctions of amyloid-laden systemic organs.

Complete neurological recovery of an adult patient with type II citrullinemia after living related partial liver transplantation.

Type II citrullinemia is an adult-onset hepatocerebral disease caused by a deficiency of argininosuccinate synthetase in liver. A 25-year-old Japanese man suddenly developed encephalopathy, showing disorientation and flapping tremor. Plasma concentrations of ammonia and citrulline were extremely high, and hepatic argininosuccinate synthetase activity was deficient. The patients condition deteriorated rapidly in spite of intensive medications. Therefore, we performed a partial liver transplantation using a graft obtained from his healthy 61-year-old father. After surgery, his neurological symptoms soon disappeared and plasma levels of ammonia and citrulline were normalized within 3 months after operation. Type II citrullinemia is one fulminant form of various liver-based metabolic diseases, and immediate liver transplantation is necessary to rescue patients with this disease. As liver transplantation from cadaveric donor is still not possible in Japan, it seems justifiable to use living related partial liver transplantation for our patient.

Transthyretin-derived amyloid deposition on the gastric mucosa in domino recipients of familial amyloid polyneuropathy liver

Familial amyloid polyneuropathy (FAP) is a form of hereditary generalized amyloidosis. Liver tissue explanted from FAP patients has normal structure and function, except for the production of amyloidogenic variant transthyretin (TTR), and domino liver transplantation (DLT) using grafts from FAP patients was first performed in 1995. FAP symptoms usually develop in genetically determined individuals after the age of 20, but it is difficult to estimate when FAP symptoms will appear in domino recipients. Concerning this problem, histological findings showing amyloid deposition have recently been obtained in a few domino recipients of FAP livers. This study investigated the presence of de novo amyloid deposition in the gastroduodenal mucosa of domino recipients transplanted at our institution. Biopsy of gastroduodenal mucosa was carried out in 5 recipients of FAP livers and TTR‐derived amyloid deposits were detected in 2 patients, both of whom had undergone DLT 47 months previously. In FAP liver recipients, de novo systemic amyloid deposition may begin much sooner than previously supposed. Therefore, careful follow‐up of domino recipients of FAP livers is required. Liver Transpl, 2006.

Marked regression of abdominal fat amyloid in patients with familial amyloid polyneuropathy during long-term follow-up after liver transplantation

To elucidate whether the amount of tissue‐deposited amyloid in familial amyloid polyneuropathy (FAP) patients decreases or increases over the long‐term course after liver transplantation (LT), we examined changes in histopathological and biochemical characteristics of abdominal fat amyloid in the transplanted patients with a postoperative history of more than 10 years. Using a series of aspirated abdominal fat tissues from 6 FAP patients with transthyretin (TTR) Val30Met variant, the severity of amyloid deposits was examined and the composition ratio of wild type‐to‐variant TTR in fat amyloid was assayed by liquid chromatography‐ion trap mass spectrometry (LC‐MS/MS). Histopathological examination of abdominal fat tissues demonstrated a significant decrease or disappearance of amyloid deposits in all 6 patients. On LC‐MS/MS analysis, the contribution of wild‐type TTR to the composition ratio in amyloid fibrils was markedly increased in all patients after LT. This is the first report showing pathological evidence that deposited amyloid in FAP patients with long posttransplantation courses can gradually regress or disappear. Liver Transpl 14:563–570, 2008.

Peripheral nerves regenerated in familial amyloid polyneuropathy after Liver transplantation

Familial amyloid polyneuropathy is a form of hereditary generalized amyloidosis that is characterized by progressive polyneuropathy and failure of the autonomic nervous system [1]. In patients with this disease, amyloid fibril proteins are single amino acid-substituted variants of transthyretin [2]; the liver produces most of the amyloid fibril proteins present in serum [3]. Liver transplantation has recently been used to treat patients with familial amyloid polyneuropathy [4-7], but little objective evidence supports the use of this treatment. In this report, we show a clear histopathologic finding that peripheral nerves regenerated in a patient with familial amyloid polyneuropathy after liver transplantation. Case Report A 31-year-old woman with a 3-year history of type I familial amyloid polyneuropathy had undergone living-related partial liver transplantation, as reported elsewhere [8, 9]. Liver transplantation from a cadaveric donor is not performed in Japan because the Japanese do not believe that brain death constitutes death. The patient had a mutant transthyretin gene with a valine to methionine substitution at position 30 (30Met transthyretin). The donor was the patients healthy 33-year-old sister. After surgery, the patients autonomic neurologic dysfunction (bowel and bladder dysfunction and orthostatic hypotension) and neuropathic symptoms in the lower limbs gradually disappeared. In addition, 30Met transthyretin in serum almost disappeared [8]. One year after transplantation, the patient returned to her previous activities. Three years after transplantation, she has no residual symptoms ascribed to familial amyloid polyneuropathy. A series of motor and sensory nerve conduction studies on the right tibial nerve showed slight improvement after transplantation: Motor nerve conduction was 43.0 m/s before and 41.0 m/s 3 years after transplantation; sensory nerve conduction was 38.0 m/s before and 48.0 m/s 3 years after transplantation (normal values: motor nerve conduction, 40 m/s; sensory nerve conduction, 35 m/s). Methods Biopsy was done on the left sural nerve before liver transplantation and on the right sural nerve 3 years after transplantation. Formalin-fixed and paraffin-embedded sections were stained with alkaline Congo red, and the characteristic apple-green birefringence of amyloid was identified under a polarizing microscope. So that we could study myelinated fiber lesions, the specimens were fixed in 3% glutaraldehyde in 0.1 mole of cacodylate buffer at a pH of 7.4, postfixed in 1% osmium tetroxide in the same buffer, and embedded in epoxy resin. Transverse sections of 1-m thickness were cut, stained with 1% toluidine blue, and examined by light microscopy. The diameter of the myelinated fiber and the density of the fiber per square millimeter of the endoneurial area were estimated from photographs enlarged to a final magnification of x1000. From these results, histograms of diameter frequency were constructed. Results Before transplantation, amyloid deposits were seen in the epineurium, perineurium, and endoneurium of the left sural nerve; a nodular pattern of amyloid deposits in the endoneurium predominated. A generalized, severe reduction in the density of nerve fibers was seen in each fascicle (Figure 1, left; Figure 2). After transplantation, a similar pattern of amyloid deposits was seen in the right sural nerve but the size of these deposits seemed stable (Figure 1, middle inset). The density of myelinated fibers was much higher after transplantation than before transplantation. In particular, the number of small myelinated fibers was much higher after transplantation than before transplantation (Figure 1, middle and right; Figure 2). Figure 1. Histopathologic and morphometric findings in the biopsy specimens obtained from the sural nerves. Left. Middle. Figure 2. Diameter-frequency histogram of myelinated fibers in the sural nerves before transplantation (black bars) and after transplantation (white bars). Discussion Before 1990, no effective treatment was available for the many intolerable symptoms of familial amyloid polyneuropathy. In 1990, physicians used liver transplantation to treat patients with this disease. Since the success of this surgery was reported [4], more than 150 patients with familial amyloid polyneuropathy throughout the world have had this treatment [10]. Follow-up studies [6, 9, 11-13], conducted over a 5-year period after transplantation, have shown early disappearance of variant transthyretins from serum and no further disease progression. In some patients, neurologic symptoms have improved and autonomic neuropathy was alleviated sooner than was peripheral somatic neuropathy. Quality of life has improved in patients who successfully recovered from surgery [14]. Most postoperative deaths occurred in patients with advanced disease [7, 9, 12]. The clinical evidence has led to a consensus that liver transplantation is a promising treatment for familial amyloid polyneuropathy. The need for early transplantation in less symptomatic patients is now emphasized. However, little objective evidence has documented the regression of amyloid deposits or the recovery of peripheral nerves. Studies of scintigraphy done by using radiolabeled serum amyloid P component have shown a significant decrease in whole-body uptake of this tracer after liver transplantation; this finding indicates that amyloid-laden lesions regressed [6]. Results on autonomic function tests improved in a patient with familial amyloid polyneuropathy who survived 8 months after liver transplantation [15]. Type I familial amyloid polyneuropathy with variant 30Met transthyretin usually features distal to proximal symmetrical involvement of peripheral nerves that starts in the legs [1]. A primary neuropathic process in this disorder is axonal degeneration caused by local amyloid deposits [16]. It is well known that the pathologic feature of sural nerve biopsy specimens is selective loss of unmyelinated and small myelinated fibers in the early stage of disease [17]. In our patient, clinical improvement was accompanied by a change in the population of myelinated fibers in the left and right sural nerves. The diffuse pattern of nerve fiber loss in the biopsy specimen of the left sural nerve obtained before liver transplantation coincided with the findings of sural nerves seen in patients with advanced type I familial amyloid polyneuropathy. The biopsy specimen obtained from the right sural nerve 3 years after transplantation revealed a substantial increase in the number of myelinated fibers and many small myelinated fibers. Because patients in whom type I familial amyloid polyneuropathy has a progressively deteriorating course seldom have well-preserved small myelinated fibers in the biopsy specimens obtained from the sural nerves [16], our findings indicate that myelinated fibers regenerate in the peripheral nerves after liver transplantation. Moreover, the reduction of amyloid mass seems to occur in the proximal portions of the long extremity nerves. This report provides valuable histopathologic evidence of the usefulness of liver transplantation as therapy for familial amyloid polyneuropathy.

Clinical and pathological studies of cardiac amyloidosis in transthyretin type familial amyloid polyneuropathy

To clarify the clinicopathological features of cardiac amyloidosis in transthyretin (TTR) familial amyloid polyneuropathy (FAP), 169 patients were divided into three groups. Group I consisted of 113 patients with ATTR Val30Met who originated from an endemic focus, II consisted of 36 patients with ATTR Val30Met in nonendemic areas, and III consisted of 20 patients who had non-Val30Met ATTRs with 15 differernt gene mutations. The median age of onset in Group I was 34 years. On our initial examination, only one 65-year-old female patient was found to be suffering from congestive heart failure. During the follow-up of 65 patients, 7 developed congestive heart failure, the average duration of their illness being 8.7 years. In Group II, the median age of onset was 53 years and 6 of the 36 patients were diagnosed as having cardiac amyloidosis in the course of this disease. In 20 autopsied patients with ATTR Val30Met, congestive heart failure was clinically seen in 6 of the 20 and all 6 showed considerably increased cardiac weight (500g or more). In Group III patients with non-Val30Met ATTRs, the median age of onset was 51.5 years and 14 of the 20 patients had cardiac amyloidosis with congestive heart failure on admission or soon after a definite diagnosis. Cardiac amyloidosis occurs in the classical form of FAP with ATTR Val30Met, especially in older patients, and is also a common clinical manvestation in FAP patients with non-Va l30Met ATTRs. In the pathogenesis of cardiac amyloidosis in A TTR FAP, aging seems to play an important role.

Feasibility of auxiliary partial orthotopic liver transplantation from living donors for patients with adult-onset type II citrullinemia

More than 20 patients with adult‐onset type II citrullinemia have undergone liver transplantation, showing dramatic therapeutic effects. In Japan, living donor liver transplantation is the standard technique of liver transplantation because of the rare availability of cadaveric donors. The feasibility of auxiliary partial orthotopic liver transplantation (APOLT) for adult‐onset type II citrullinemia to overcome the problem of a small‐for‐size graft in living donor liver transplantation has not been defined. We recently performed APOLT for patients with type II citrullinemia. Here, we present 2 patients: patient 1 was a 32‐year‐old man and patient 2 was a 43‐year‐old woman. Both patients suffered from hepatic encephalopathy, and laboratory data showed highly elevated plasma levels of ammonia and citrulline. In patient 1, the liver graft was obtained from a patient with familial amyloid polyneuropathy as a domino liver transplant. In patient 2, APOLT was performed after graft donation from her husband. The postoperative clinical courses of both patients were uneventful, and the neurological symptoms were completely resolved. The plasma concentrations of ammonia and citrulline normalized rapidly in both patients. APOLT can provide an adequate hepatocyte mass to correct the underlying enzyme deficiency in adult patients with type II citrullinemia. In addition, APOLT can be carried out safely to overcome the limitation of graft volume in living donor liver transplantation. (Liver Transpl 2004;10:550–554.)