Anesthesia management protocol for liver transplantation as treatment for ornithine transcarbamylase deficiency.

BACKGROUND: Ornithine transcarbamylase deficiency is an X-linked genetic disorder that induces accumulation of ammonia in the liver and is the most common urea cycle disorder. The clinical manifestation of ornithine transcarbamylase deficiency is hyperammonemia that causes irreversible neurological damage. Liver transplantation is a curative therapy for ornithine transcarbamylase deficiency. The aim of this study is to suggest, from our previous experience, an anesthesia management protocol of liver transplantation for ornithine transcarbamylase deficiency, particularly focused on liver transplantation for cases with uncontrolled hyperammonemia. METHOD: We retrospectively reviewed our anesthesia-related experience in all cases of liver transplantation for ornithine transcarbamylase deficiency in our center. RESULTS: Twenty-nine liver transplantation cases for ornithine transcarbamylase deficiency were found between November 2005 and March 2021 in our center. Of these, 25 cases were stable through the perioperative period. However, 2 cases with carrier donor graft had hyperammonemia after liver transplantation. Another two cases had uncontrolled hyperammonemia before liver transplantation, even with continuous hemodialysis. They underwent life-saving liver transplantation. Their metabolic status stabilized after the anhepatic phase. CONCLUSION: Liver transplantation for cases with uncontrolled hyperammonemia can be performed with proper management. Second, liver transplantation with carrier donors should be avoided because of the risk of postoperative recurrence.

Successful liver transplantation in hyperornithinemia-hyperammonemia-homocitrullinuria syndrome: Case report.

BACKGROUND: HHH syndrome is a rare autosomal recessive disorder of the urea cycle, caused by a deficient mitochondrial ornithine transporter. We report the first successful liver transplantation in HHH syndrome performed in a seven-year-old boy. The patient presented at 4 weeks of age with hyperammonemic coma. The plasma amino acid profile was suggestive of HHH syndrome, and the diagnosis was confirmed when sequencing of the SLC25A15 gene identified two mutations p.R275Q and p.A76D. Although immediate intervention resulted in normalization of plasma ammonia levels within 24 hours, he developed cerebral edema, coma, convulsions, and subsequent neurological sequelae. Metabolic control was difficult requiring severe protein restriction and continued treatment with sodium benzoate and L-arginine. Despite substantial developmental delay, he was referred to our center for liver transplantation because of poor metabolic control. Following cadaveric split liver transplantation, there was complete normalization of his plasma ammonia and plasma amino acid levels under a normal protein-containing diet. This excellent metabolic control was associated with a markedly improved general condition, mood and behavior, and small developmental achievements. Twelve years after liver transplantation, the patient has a stable cognitive impairment without progression of spastic diplegia. CONCLUSION: This first case of liver transplantation in HHH syndrome demonstrates that this procedure is a therapeutic option for HHH patients with difficult metabolic control.

Non-cirrhotic Extra-Hepatic Porto-Systemic Shunt Causing Adult-Onset Encephalopathy Treated with Endovascular Closure.

INTRODUCTION: Encephalopathy secondary to hyperammonemia due to Congenital Extra-hepatic Porto-systemic shunt (CEPS) in the absence of liver cirrhosis is an exceptionally unusual condition. We describe the case of a 54-year-old woman admitted to the Emergency Department complaining of recurrent episodes of confusion and worsening cognitive impairment. At admission, the patient displayed slowing cognitive-motor skills with marked static ataxia and impaired gait. Hyperammonemia was detected in the serum. An abdominal computed tomography (CT) excluded portal hypertension and liver cirrhosis, detecting a congenital extra-hepatic porto-systemic shunt which is a highly unusual vascular malformation. The patient was treated by interventional radiologists with a successful endovascular closure. AREAS COVERED: We have performed a review of the last three decades of the literature, starting from the introduction of CT scanning in common clinical practice. Eighteen studies (case reports) described 29 patients with encephalopathy secondary to hyperammonemia due to CEPS in the absence of liver cirrhosis: They underwent treatment similar to our case report of CEPS. EXPERT COMMENTARY: Encephalopathy secondary to hyperammonemia in the absence of hepatic dysfunction is an important diagnostic dilemma to many clinicians. An interventional radiologic approach is currently preferred.

Acute hyperammonemic encephalopathy due to a portosystemic shunt in a non-cirrhotic adult patient.

OBJECTIVE: To report a successfully treated hyperammonemia due to a portosystemic shunt in adult patient. DATA SOURCE: A patient with an altered mental status due to severe elevated ammonia level because of a portosystemic shunt. CONCLUSIONS: Hyperammonemia is not always related to liver failure in critically ill patients, but should be considered in all unknown origins of an altered mental status. A portosystemic shunt can be the responsible for this phenomenon, and it has a newly treatment technique named plug-assisted retrograde transvenous obliteration (PARTO), which can be quickly performed with high technical success rate and clinical efficacy for the treatment of the splenorenal and/or gastrorenal shunt.

Reversal of secondary protein-losing enteropathy after surgical revision of a jejunal Roux-en-Y loop in a patient after liver transplantation.

Secondary protein-losing enteropathy (PLE) is a rare complication following pediatric liver transplantation (LT), mostly related to venous outflow obstruction of the liver. Here, we discuss a thus far unknown cause of secondary PLE following pediatric LT. A 7-month-old boy underwent LT with biliary anastomosis using a Roux-en-Y jejunal loop. Eleven months later he developed PLE. Routine diagnostic workup was negative. No hepatic outflow obstruction was detected during catheterization. Although the hepatic venous pressure gradient was slightly increased (10 mm Hg), there were no clinical signs of portal hypertension. Albumin scintigraphy with specific early recordings suggested focal albumin intestinal entry in the jejunal Roux-en-Y loop. Local bacterial overgrowth or local lymphangiectasia, possibly due to (venous) congestion, was considered. Treatment with metronidazole did not improve albumin loss. Next, surgical revision of the jejunal Roux-en-Y loop was performed. The explanted loop contained a small abnormal area with a thin hyperemic mucosa, near the former anastomosis. Histopathological analysis showed changes both in the blood vessels and the lymphatic vessels with focal deeper chronic active inflammation resulting in congestion of vessels, hampering lymphatic outflow leading to lymphangiectasia and patchy distortion of lymphatic vessels. Following surgical revision, secondary PLE disappeared, up to now, 1.5 year post revision.

Laparoscopic ligation of a congenital extrahepatic portosystemic shunt for children with hyperammonemia: a single-institution experience.

PURPOSE: A congenital extrahepatic portosystemic shunt (CEPS) associated with hyperammonemia requires occlusion of the shunt vessels. We evaluated the effectiveness and safety of laparoscopic ligation of a CEPS in children with hyperammonemia. METHODS: The subjects of this retrospective study were seven children with hyperammonemia who underwent laparoscopic ligation of a CEPS. Their median age was 5.2 years (range 1-16 years). Before the laparoscopic procedure, a catheter was inserted through the femoral vein and placed in the portal vein via the shunt vessel. The shunt vessel was dissected and taped laparoscopically. After measuring the portal vein pressure under temporal occlusion, the shunt vessels were ligated. RESULTS: The types of shunts according to location were patent ductus venosus (n = 2), splenorenal shunt (n = 2), gastrorenal shunt (n = 2), and superior mesenteric vein-inferior vena cava shunt (n = 1). Laparoscopic ligation of the shunt vessel was completed uneventfully in all patients. The median portal vein pressure was 19 mmHg after ligation. The median preoperative blood ammonia level was 94 µg/dL (range 71-259 µg/dL), which decreased after ligation in all patients. There was no incidence of postoperative liver failure. CONCLUSION: Laparoscopic ligation of a CEPS is safe and effective for children with hyperammonemia.

Curative Treatment of Ornithine Transcarbamylase Deficiency With a Liver Transplant: A Case Report.

One of the X chromosome-linked disorders is ornithine transcarbamylase deficiency in the urea cycle. This disorder results in increased ammonia and glutamine in the blood. Accumulation of these metabolites without treatment causes brain edema, which often progresses to coma and death. This study describes a 5-year-old girl with ornithine transcarbamylase deficiency who presented with hyperammonemic encephalopathy that was successfully treated with an orthotropic liver transplant. Recently, liver transplant has been introduced as an alternative treatment for patients with ornithine transcarbamylase deficiency.

Excessively Long Duodenum of the Pancreatic Graft Segment as a Rare Cause of Hyperammonemia After Simultaneous Pancreas-Kidney Transplant.

Simultaneous pancreas-kidney transplant is currently standard therapy to achieve long-term insulin-free euglycemia in patients with type 1 diabetes mellitus and concomitant end-stage kidney failure. A patient with symptoms of encephalopathy caused by hyperammonemia and with new-onset iron deficiency anemia was admitted to our institution 20 months after a simultaneous pancreas-kidney transplant. Detailed screening did not reveal any specific cause for the hyperammonemia, and despite standard treatment, hyperammonemia did not resolve. An abdominal computed tomographic scan was performed, which showed a distended duodenal segment of the pancreas graft. This was confirmed during exploratory laparotomy when the anastomosis between duodenum and ileum was dismantled and found not to be stenotic. The excessively long stumps of the duodenum were then dissected and shortened, and a new anastomosis between graft-duodenum and recipient-ileum was created. The operation was followed by an uncomplicated postoperative course in which the serum ammonia normalized on the first postoperative day and remained normal afterwards. An excessively long segment of the duodenum of the pancreatic graft may lead to encephalopathy with hyperammonemia after a simultaneous pancreas-kidney transplant. This emphasizes the need for meticulous preparation of the graft to avoid this complication.

Human heterologous liver cells transiently improve hyperammonemia and ureagenesis in individuals with severe urea cycle disorders.

BACKGROUND: Urea cycle disorders (UCDs) still have a poor prognosis despite several therapeutic advancements. As liver transplantation can provide a cure, liver cell therapy (LCT) might be a new therapeutic option in these patients. METHODS: Twelve patients with severe UCDs were included in this prospective clinical trial. Patients received up to six infusions of cryopreserved human heterologous liver cells via a surgically placed catheter in the portal vein. Portal vein pressure, portal vein flow, and vital signs were monitored continuously. Calcineurin inhibitors and steroids were used for immunosuppression. In four patients, ureagenesis was determined with stable isotopes. Number and severity of hyperammonemic events and side effects of immunosuppression were analyzed during an observation period of up to 2 years. RESULTS: No study-related mortality was observed. The application catheter dislocated in two children. No significant side effects of catheter application or cell infusion were noted in the other ten patients. The overall incidence of infections did not differ significantly from a historical control group, and no specific side effects of immunosuppression were found. Seven patients were treated per protocol and could be analyzed for efficacy. Severe metabolic crises could be prevented in all of these patients, moderate crises in four of seven. Ureagenesis increased after cell infusion in all patients investigated. CONCLUSIONS: We found a favorable safety profile with respect to catheter placement, intraportal liver cell infusion, and immunosuppression. More than half of the children treated per protocol experienced metabolic stabilization and could be safely bridged to liver transplantation.

Clinical course of 63 patients with neonatal onset urea cycle disorders in the years 2001-2013.

BACKGROUND: Urea cycle disorders (UCDs) are rare inherited metabolic defects of ammonia detoxification. In about half of patients presenting with a UCD, the first symptoms appear within a few days after birth. These neonatal onset patients generally have a severe defect of urea cycle function and their survival and outcome prognoses are often limited. To understand better the current situation of neonatal onset in UCDs, we have performed a multicentre, retrospective, non-interventional case series study focussing on the most severe UCDs, namely defects of carbamoyl phosphate synthetase 1 (CPS1), ornithine transcarbamylase (OTC), and argininosuccinate synthetase (ASS). METHODS AND RESULTS: Data of 63 patients were collected (27 patients with ASS deficiency, 23 patients with OTC deficiency, and 12 patients with CPS1 deficiency, one patient definite diagnosis not documented). The majority of patients (43/63, 68 %) had an initial ammonia concentration exceeding 500 µmol/L (normal < 100), of which most (26/43, 60.5 %) were also encephalopathic and were treated with hemodialysis. In patients surviving the initial crisis, recurrence of hyperammonemic events within the first 1.5 years of life occurred frequently (mean 3.6 events, range 0-20). Of all patients, 16 (25.4 %) died during or immediately after the neonatal period. CONCLUSION: We observed in this cohort of neonatal onset UCD patients a high rate of initial life-threatening hyperammonemia and a high risk of recurrence of severe hyperammonemic crises. These corresponded to a high mortality rate during the entire study period (30.2 %) despite the fact that patients were treated in leading European metabolic centers. This underlines the need to critically re-evaluate the current treatment strategies in these patients.

Surgery for gastric cancer in a patient with non-cirrhotic hyperammonemia: a case report.

We report a case of gastric cancer in a patient with non-cirrhotic hyperammonemia secondary to a spontaneous portacaval shunt. The patient, a 69-year-old male, had more than 40 years of abdominal discomfort. On gastroscopy, 2.0 × 1.5-cm irregular uplift ulcers were seen on the lesser curvature of the stomach, and tissue biopsy revealed poorly differentiated adenocarcinoma. His hyperammonemia was found on celiac angiography to be due to the formation of a spontaneous portacaval shunt. Imaging revealed no evidence of cirrhosis or portal hypertension. The patient ultimately underwent a distal gastrectomy and gastroduodenal anastomosis; the spontaneous portacaval shunt was left untreated. Postoperatively, there were no short-term complications such as anastomotic leakage, stricture, or bleeding, and the patient's blood ammonia level decreased to within the normal range. Radical gastrectomy without splenectomy or closure of the abnormal shunt was feasible for the treatment of gastric cancer in a patient with non-cirrhotic hyperammonemia.

[Liver transplantation for the treatment of hyperammonemia due to urea cycle disorder: report of four cases].

OBJECTIVE: To analyze clinical efficacy and prognosis of liver transplantation in children with hyperammonemia caused by urea cycle disorders. METHOD: A retrospective analysis was performed on the occurrence of disease, operation and the follow-up post liver transplantation in 4 patients with urea cycle disorders who underwent liver transplantation during June 2001 to May 2014. RESULT: Four girls were diagnosed with ornithine carbamoyl transferase deficiency by genetic test. They had the clinical onset at the age of 1.5 to 3.0 years. Liver transplantation had been performed at their age of 53.9 months, 40.6 months, 40.3 months and 22.8 months, respectively. The grafts of case 1 and case 2 were from left lateral lobe of liver of cadaveric donor, the graft of case 3 was from left lateral lobe of liver of a living donor, the graft of case 4 was a whole liver of a dead child. The liver function of 4 patients gradually returned to normal, blood ammonia levels were normal and restored the normal diet, 4 children were discharged on postoperative 25-30 days. Regular follow-up was done, the liver function, biochemical features and growth status have been followed up for 162.2 months, 124.2 months, 12.0 months and 4.8 months after liver transplantation, respectively. Now, all the four cases are healthy and growth is normal. CONCLUSION: Liver transplantation is an important way to the patients with severe hyperammonemia caused by urea cycle disorders. In this study, the patients with ornithine carbamoyl transferase defect got satisfactory long-term outcome after liver transplantation.

[Clinical effect of stem cell transplantation via hepatic artery in the treatment of type II hyperammonemia: a report on 6 cases].

This study aimed to investigate the clinical effect of transplantation of CD133⁺ peripheral blood stem cells or umbilical cord mesenchymal stem cells via the hepatic artery in children with type II hyperammonemia and its possible action mechanism. Umbilical cord mesenchymal stem cells were obtained by collecting cord blood (100-150 mL) from healthy fetuses and separating stem cell suspension (5 mL) from the cord blood by hydroxyethyl starch sedimentation. CD133⁺ peripheral blood stem cells were obtained by mobilizing peripheral blood from the fathers of sick children using recombinant human granulocyte colony-stimulating factor for 5 days, collecting mononuclear cells (120 mL), and separating out CD133⁺ cells by sorting. With catheterization and percutaneous puncture, the obtained stem cells were slowly injected into the liver of sick children via the hepatic artery. The changes in clinical symptoms and laboratory indices such as blood ammonia, liver function, and arginine and citrulline concentrations were observed. After stem cell transplantation via the hepatic artery, the 6 children showed significantly decreased blood ammonia levels, and their blood ammonia levels slowly increased 1 to 2 weeks later, but remained below 100 µmol/L, and changes in glutamic-pyruvic transaminase levels were similar to blood ammonia. Plasma citrulline and arginine concentrations increased significantly after transplantation and the increase in citrulline level exceeded the increase in arginine level. An 8 months follow-up visit for one typical patient showed that the weight and height increased after transplantation and sleep was improved without night crying. The child could actively gaze at interesting objects instead of responding indifferently and started to say simple words. With regard to fine motor skills, the child could pinch things with the thumb and middle finger instead of displaying a lack of hand-eye coordination and progress was also made in gross motor skills. Gesell test showed that the child made progress for an average of 3.82 months in all areas. It was concluded that after stem cell transplantation, children with type II hyperammonemia have decreased blood ammonia levels, stable and improved liver function and steadily increased plasma citrulline and arginine concentrations. They display a progressive trend in such aspects as movement, language and environmental adaptability. It is hypothesized that stem cell transplantation via the hepatic artery partially or totally activates, or provides supplementary ornithine carbamoyl transferase, so that plasma citrulline and arginine concentrations increase and urea cycle disorder can be corrected to some extent.

Management and classification of type II congenital portosystemic shunts.

BACKGROUND: Congenital portosystemic shunts (PSS) with preserved intrahepatic portal flow (type II) present with a range of clinical signs. The indications for and benefits of repair of PSS remain incompletely understood. A more comprehensive classification may also benefit comparative analyses from different institutions. METHODS: All children treated at our institution for type II congenital PSS from 1999 through 2009 were reviewed for presentation, treatment, and outcome. RESULTS: Ten children (7 boys) with type II PSS were identified at a median age of 5.5 years. Hyperammonemia with varying degrees of neurocognitive dysfunction occurred in 80%. The shunt arose from a branch of the portal vein (type IIa; n = 2), from the main portal vein (type IIb; n = 7), or from a splenic or mesenteric vein (type IIc; n = 1). Management included operative ligation (n = 6), endovascular occlusion (n = 3), or a combined approach (n = 1). Shunt occlusion was successful in all cases. Serum ammonia decreased from 130 ± 115 µmol/L preoperatively to 31 ± 15 µmol/L postoperatively (P = .03). Additional benefits included resolution of neurocognitive dysfunction (n = 3), liver nodules (n = 1), and vaginal bleeding (n = 1). CONCLUSION: Correction of type II PSS relieves a wide array of symptoms. Surgery is indicated for patients with clinically significant shunting. A refined classification system will permit future comparison of patients with similar physiology.

A new experimental model for acute hepatic failure in rats / Novo modelo experimental em ratos para insuficiência hepática aguda

PURPOSE: To develop a reliable surgical model of acute hepatic failure and hyperammonemia in rats that avoids porto-systemic shunt and bile duct ligation, applicable to hepatic encephalopathy research. METHODS: The pedicles of right lateral and caudate lobes were exposed and clamped. One hour later, the animal was reopened, clamps were released and anterior subtotal hepatectomy (resection of median and left lateral lobes) was performed, comprising 75 percent of liver removal. Four hours after hepatectomy, blood samples and liver tissues were collected from ALF and control groups. RESULTS: Differences between ALF and control groups were significant for ALT, AST, total and direct bilirubin, sodium, potassium, alkaline phosphatasis, gamma-glutamyltransferase and most important, ammonia. Histologically, significant differences were noticed between groups. CONCLUSION: The model is useful for the study of specific aspects of ALF and the development of new therapeutic approaches.

OBJETIVO: Desenvolver um modelo cirúrgico de IHA e hiperamonemia em ratos, que evita o shunt porto-sistêmico e a ligadura do ducto biliar, que seja aplicável à pesquisa de encefalopatia hepática. MÉTODOS: Após anestesia geral e laparotomia mediana, os pedículos dos lobos laterais direito e caudado foram isolados e clampeados. Após 1 hora, o animal foi reaberto, os clampes retirados e foi realizada hepatectomia anterior subtotal (ressecção dos lobos médio e lateral esquerdo), compreendendo a remoção de 75 por cento do parênquima. Quatro horas após a hepatectomia, amostras de sangue e tecido hepático foram coletadas nos grupos IHA e controle. RESULTADOS: Diferenças entre os grupos IHA e controle foram significativas para ALT, AST, bilirrubina total e direta, sódio, potássio, fosfatase alcalina, gama glutamiltransferase e principalmente amônia. Histologicamente, diferenças significativas foram observadas entre os grupos. CONCLUSÃO: O modelo é útil para o estudo de aspectos específicos da IHA e o desenvolvimento de novas abordagens terapêuticas.

A new experimental model for acute hepatic failure in rats.

PURPOSE: To develop a reliable surgical model of acute hepatic failure and hyperammonemia in rats that avoids porto-systemic shunt and bile duct ligation, applicable to hepatic encephalopathy research. METHODS: The pedicles of right lateral and caudate lobes were exposed and clamped. One hour later, the animal was reopened, clamps were released and anterior subtotal hepatectomy (resection of median and left lateral lobes) was performed, comprising 75% of liver removal. Four hours after hepatectomy, blood samples and liver tissues were collected from ALF and control groups. RESULTS: Differences between ALF and control groups were significant for ALT, AST, total and direct bilirubin, sodium, potassium, alkaline phosphatasis, gamma-glutamyltransferase and most important, ammonia. Histologically, significant differences were noticed between groups. CONCLUSION: The model is useful for the study of specific aspects of ALF and the development of new therapeutic approaches.

Endovascular diagnosis and intervention in patients with isolated hyperammonemia, with or without ascites, after liver transplantation.

Hyperammonemia with or without ascites with normal synthetic liver functions after liver transplantation might indicate the presence of anastomotic stenosis of the portal or hepatic vein or the existence of a patent portosystemic shunt. The authors describe six patients, three children after split-liver transplantation and three adults after cadaver liver transplantation, who presented with hyperammonemia. Three patients had ascites. All lesions were successfully treated percutaneously; stents were placed in patients with anastomotic stenoses and coil embolization was performed in patients with patent portosystemic shunts--with either transhepatic or transjugular approaches according to the site of the abnormality. Ammonia levels returned to normal, and ascites had regressed completely for at least 3 months.