Central nervous system complications in liver transplant recipients--incidence, timing, and long-term follow-up

Risk of Cerebral Aneurysm Rupture After Liver Transplantation: Development and Validation of a Hemorrhagic Stroke Scoring Model

BACKGROUND

Liver transplantation (LT) patients appear to be more prone to neurological events compared to individuals undergoing other types of solid-organ transplantation. The aims of the present study were to analyze the prevalence of unruptured intracranial aneurysms (UIAs) in patients undergoing liver transplantation (LT) and to examine the perioperative occurrence of subarachnoid hemorrhage (SAH). Also, it intended to systematically identify the risk factors of SAH and hemorrhagic stroke (HS) within a year after LT and to develop a scoring system which involves distinct clinical features of LT patients.

METHODS

Patients who underwent LT from January 2012 to March 2022 were analyzed. All included patients underwent neurovascular imaging within 6 months before LT. We conducted an analysis of prevalence and radiological features of UIA and SAH. The clinical factors that may have an impact on HS within one year of LT were also reviewed.

RESULTS

Total of 3,487 patients were enrolled in our study after applying inclusion and exclusion criteria. The prevalence of UIA was 5.4%. The incidence of SAH and HS within one year following LT was 0.5% and 1.6%, respectively. We developed a scoring system based on multivariable analysis to predict the HS within 1-year after LT. The variables were a poor admission mental status, the diagnosis of UIA, serum ammonia levels, and Model for End-stage Liver Disease (MELD) scores. Our model showed good discrimination among the development (C index, 0.727; 95% confidence interval [CI], 0.635-0.820) and validation (C index, 0.719; 95% CI, 0.598-0.801) cohorts.

CONCLUSION

The incidence of UIA and SAH was very low in LT patients. A poor admission mental status, diagnosis of UIA, serum ammonia levels, and MELD scores were significantly associated with the risk of HS within one year after LT. Our scoring system showed a good discrimination to predict the HS in LT patients.

Hyponatremia in the Context of Liver Disease

Hyponatremia is common in patients with liver disease and is associated with increased mortality, morbidity, and a reduced quality of life. In liver transplantation, the inclusion of hyponatremia in organ allocation scores has reduced waitlist mortality. Portal hypertension and the resulting lowering of the effective arterial blood volume are important pathogenetic factors, but in most patients with liver disease, hyponatremia is multifactorial. Treatment requires a multifaceted approach that tries to reduce electrolyte-free water intake, restore urinary dilution, and increase nonelectrolyte solute excretion. Albumin therapy for hyponatremia is a peculiarity of advanced liver disease. Its use appears to be increasing, while the vaptans are currently only given in selected cases. Osmotic demyelination is a special concern in patients with liver disease. Serial checks of serum sodium concentrations and urine volume monitoring are mandatory.

Clinical Impact and Risk Factors of Seizure After Liver Transplantation: A Nested Case-Control Study

Seizures are a frequent neurological consequence following liver transplantation (LT), however, research on their clinical impact and risk factors is lacking. Using a nested case-control design, patients diagnosed with seizures (seizure group) within 1-year post-transplantation were matched to controls who had not experienced seizures until the corresponding time points at a 1:5 ratio to perform survival and risk factor analyses. Seizures developed in 61 of 1,243 patients (4.9%) at median of 11 days after LT. Five-year graft survival was significantly lower in the seizure group than in the controls (50.6% vs. 78.2%, respectively, p < 0.001) and seizure was a significant risk factor for graft loss after adjusting for variables (HR 2.04, 95% CI 1.24-3.33). In multivariable logistic regression, body mass index <23 kg/m2, donor age ≥45 years, intraoperative continuous renal replacement therapy and delta sodium level ≥4 mmol/L emerged as independent risk factors for post-LT seizure. Delta sodium level ≥4 mmol/L was associated with seizures, regardless of the severity of preoperative hyponatremia. Identifying and controlling those risk factors are required to prevent post-LT seizures which could result in worse graft outcome.

Early neurologic complications after liver transplant are associated with reduced long-term survival and increased rates of rejection

Neurologic complications (NCs) are common following liver transplantation (LT) and have been associated with impaired short-term survival. The impact of NC on long-term survival is less defined. We aimed to characterize these outcomes and assess for risk factors for post-LT NC. We performed a single-center, retrospective review of 521 patients with LT from 2016 to 2020. Baseline clinical and laboratory factors, intraoperative events, and outcomes were compared between patients with and without NC. The 5-year overall and rejection-free survival was estimated using the Kaplan-Meier analysis. Multivariable logistic regression assessed for an independent relationship between risk factors and the development of NC. Among 521 LT recipients, 24% experienced post-LT NC. Overall and rejection-free survival at 5 years was, respectively, 69% and 75% among those with NC versus 87% and 88% among those without NC (log-rank < 0.001). Among those who survived the first 3 months after LT, overall survival but not rejection-free survival was reduced among patients with NC. Risk factors for developing NC included peri-LT serum sodium (ΔSNa) ≥ 6 (29.4% vs. 20.5%, p = 0.04), grade 3 or 4 HE pre-LT, SNa < 125 pre-LT, and more intraoperative transfusions. In a multivariable logistic regression model controlling for described variables, SNa < 125 (or 0.21, 95% CI, 0.06-0.74) at LT and pre-LT HE grade 3 or 4 (or 0.45, 95% CI, 0.26-0.76) was independently associated with NC. Long-term survival was reduced among patients who developed NC in the immediate post-transplant period, even when censoring those who died in the first 3 months. Post-LT NC was associated with perioperative ΔSNa ≥ 6. Optimization of SNa pre-LT > 125 and limiting perioperative ΔSNa <6 mEq/L might have a beneficial impact in decreasing NC post-LT, which may improve long-term post-LT survival.

Complications in Post-Liver Transplant Patients

Liver transplantation (LT) is the treatment of choice for liver failure and selected cases of malignancies. Transplantation activity has increased over the years, and indications for LT have been widened, leading to organ shortage. To face this condition, a high selection of recipients with prioritizing systems and an enlargement of the donor pool were necessary. Several authors published their case series reporting the results obtained with the use of marginal donors, which seem to have progressively improved over the years. The introduction of in situ and ex situ machine perfusion, although still strongly debated, and better knowledge and treatment of the complications may have a role in achieving better results. With longer survival rates, a significant number of patients will suffer from long-term complications. An extensive review of the literature concerning short- and long-term outcomes is reported trying to highlight the most recent findings. The heterogeneity of the behaviors within the different centers is evident, leading to a difficult comparison of the results and making explicit the need to obtain more consent from experts.

Bidirectional Communication Between the Brain and Other Organs: The Role of Extracellular Vesicles

A number of substances released by the brain under physiological and pathological conditions exert effects on other organs. In turn, substances produced primarily by organs such as bone marrow, adipose tissue, or the heart may have an impact on the metabolism and function and metabolism of the healthy and diseased brain. Despite a mounting amount of evidence supports such bidirectional communication between the brain and other organs, research on the function of molecular mediators carried by extracellular vesicles (EVs) is in the early stages. In addition to being able to target or reach practically any organ, EVs have the ability to cross the blood-brain barrier to transport a range of substances (lipids, peptides, proteins, and nucleic acids) to recipient cells, exerting biological effects. Here, we review the function of EVs in bidirectional communication between the brain and other organs. In a small number of cases, the role has been explicitly proven; yet, in most cases, it relies on indirect evidence from EVs in cell culture or animal models. There is a dearth of research currently available on the function of EVs-carrying mediators in the bidirectional communication between the brain and bone marrow, adipose tissue, liver, heart, lungs, and gut. Therefore, more studies are needed to determine how EVs facilitate communication between the brain and other organs.

Characteristics of stroke after liver and kidney transplantation

Background

The mechanism and characteristics of a post-transplantation stroke may differ between liver (LT) and kidney transplantation (KT), as the associated comorbidities and peri-surgical conditions are different. Herein, we investigated the characteristics and etiologies of stroke occurring after LT and KT.

Methods

Consecutive patients who received LT or KT between January 2005 to December 2020 who were diagnosed with ischemic or hemorrhagic stroke after transplantation were enrolled. Ischemic strokes were further classified according to the etiologies. The characteristics of stroke, including in-hospital stroke, perioperative stroke, stroke etiology, and timing of stroke, were compared between the LT and KT groups.

Results

There were 105 (1.8%) and 58 (1.3%) post-transplantation stroke patients in 5,950 LT and 4,475 KT recipients, respectively. Diabetes, hypertension, and coronary arterial disease were less frequent in the LT than the KT group. In-hospital and perioperative strokes were more common in LT than in the KT group (LT, 57.9%; KT, 39.7%; p = 0.03, and LT, 43.9%; KT, 27.6%; p = 0.04, respectively). Hemorrhagic strokes were also more common in the LT group (LT, 25.2%; KT, 8.6%; p = 0.01). Analysis of ischemic stroke etiology did not reveal significant difference between the two groups; undetermined etiology was the most common, followed by small vessel occlusion and cardioembolism. The 3-month mortality was similar between the two groups (both LT and KT, 10.3%) and was independently associated with in-hospital stroke and elevated C-reactive protein.

Conclusions

In-hospital, perioperative, and hemorrhagic strokes were more common in the LT group than in the KT group. Ischemic stroke subtypes did not differ significantly between the two groups and undetermined etiology was the most common cause of ischemic stroke in both groups. High mortality after stroke was noted in transplantation patients and was associated with in-hospital stroke.

Central Nervous System Infections in Solid Organ Transplant Recipients: Results from the Swiss Transplant Cohort Study

OBJECTIVES

To describe the epidemiology and clinical presentation of central nervous system (CNS) infections in solid organ transplant (SOT) recipients in the current era of transplantation.

METHODS

Patients from the Swiss Transplant Cohort Study (STCS) transplanted between 2008 and 2018 were included with a median follow-up of 3.8 years. Epidemiological, microbiological, and clinical data were extracted from the STCS database and patients' medical records. We calculated incidence rates and 90-day survival of transplant recipients with CNS infection.

RESULTS

Among 4762 patients, 42 episodes of CNS infection in 41 (0.8%) SOT recipients were identified, with an overall incidence rate of 2.06 per 1000 patient-years. Incidence of CNS infections was similar across all types of transplantations. Time to CNS infection onset ranged from 0.6 to 97 months after transplant. There were 22/42 (52.4%) cases of viral infections, 11/42 (26.2%) of fungal infections, 5/42 (11.9%) of bacterial infections and 4/42 (9.5%) of probable viral/bacterial etiology. Clinical presentation was meningitis/encephalitis in 25 cases (59.5%) and brain-space occupying lesions in 17 cases (40.5%). Twenty-three cases (60.5%) were considered opportunistic infections. Diagnosis were achieved mainly by brain biopsy/necropsy (15/42, 36%) or by cerebrospinal fluid analysis (20/42, 48%). Up to 40% of cases (17/42) had concurrent extra-neurological disease localizations. Overall, 90-day mortality rate was 29.0% (73.0% for fungal, 14.0% for viral and 11.0% for bacterial and probable infections, p<0.0001).

CONCLUSIONS

CNS infections were rare in the STCS, with viral meningoencephalitis being the most common disease. Fungal infections were associated with a high mortality.

The Use of Hepatitis C Virus-Positive Organs in Hepatitis C Virus-Negative Recipients

The use of hepatitis C virus (HCV) -positive organs in HCV-negative recipients with posttransplant antiviral treatment has increasingly been studied since the introduction of new direct-acting antivirals. This article reviews existing experience in liver and kidney transplant. Fifteen studies with 218 HCV D+/R- liver transplants, with 182 from viremic donors, show a sustained viral response for 12 weeks (SVR12) rate of 99.5%. Nine studies involving 204 HCV donor-positive recipient-negative kidney transplant recipients had an SVR12 rate of 99.5%. Complications are infrequent. Preemptive treatment in kidney transplant of for only 4 weeks or even 4 days showed surprising success rates.

Hyponatremia and Liver Transplantation: A Narrative Review

Hyponatremia is a common electrolyte disorder in patients with end-stage liver disease (ESLD) and is associated with increased mortality on the liver transplantation (LT) waiting list. The impact of hyponatremia on outcomes after LT is unclear. Ninety-day and one-year mortality may be increased, but the data are conflicting. Hyponatremic patients have an increased rate of complications and longer hospital stays after transplant. Although rare, osmotic demyelination syndrome (ODS) is a feared complication after LT in the hyponatremic patient. The condition may occur when the serum sodium (sNa) concentration increases excessively during or after LT. This increase in sNa concentration correlates with the degree of preoperative hyponatremia, the amount of intraoperative blood loss, and the volume of intravenous fluid administration. The risk of developing ODS after LT can be mitigated by avoiding large perioperative increases in sNa concentration . This can be achieved through measures such as carefully increasing the sNa pretransplant, and by limiting the intravenous intra- and postoperative amounts of sodium infused. SNa concentrations should be monitored regularly throughout the entire perioperative period.

Osmotic Demyelination Syndrome in Hospitalized Patients With Cirrhosis: Analysis of the National Inpatient Sample (NIS)

GOAL

Characterize prevalence of osmotic demyelination syndrome (ODS) in hospitalized patients with cirrhosis.

BACKGROUND

ODS is a serious complication of rapid serum sodium correction. Patients with cirrhosis experience labile sodium levels related to portal hypertension and diuretic use, often with rapid correction-intentional or unintentional-during hospitalizations.

STUDY

We used validated International Classification of Diseases, Ninth Revision (ICD-9) codes to identify inpatients 18 years and older with cirrhosis from the 2009-2013 National Inpatient Sample, excluding those with liver transplantation during hospitalization. The primary outcome was ODS (ICD-9 341.8). Baveno IV defined decompensated cirrhosis (stages 3 and 4); Charlson Comorbidity Index identified severe comorbid illness (score >3). Logistic regression modeled factors associated with ODS.

RESULTS

Of 547,544 adult inpatients with cirrhosis, 94 (0.02%) had ODS. Inpatients with versus without ODS were younger (54 vs. 57 y, P=0.0001), and more likely to have alcohol-related cirrhosis (58% vs. 33%, P<0.0001). ODS did not associate with decompensated cirrhosis (33% vs. 37%, P=0.43), specific complications (ascites 33% vs. 33%, P=0.97; hepatic encephalopathy 24% vs. 17%, P=0.06), or severe comorbid illness (12% vs. 16%, P=0.24). In both univariable and multivariable analysis, age [adjusted odds ratio (ORadj): 0.97, 95% confidence interval (CI): 0.95-0.99], female gender (ORadj: 1.53, 95% CI: 1.01-2.30), Hispanic race (ORadj: 0.41, 95% CI: 0.19-0.89), alcohol-related cirrhosis (ORadj: 2.65, 95% CI: 1.71-4.09), and congestive heart failure (ORadj: 0.37, 95% CI: 0.15-0.95) significantly associated with ODS.

CONCLUSION

In hospitalized patients with cirrhosis, ODS is extremely rare, and associated with alcohol-related cirrhosis, younger age, and female gender. ODS is not associated with liver disease severity, specific complications including ascites, or comorbid disease.

Cerebral Diseases in Liver Transplant Recipients: Systematic Review of Clinical Evidence

This systematic review presents clinical evidence on early and long-term cerebral diseases in liver transplant recipients. The literature search led to the retrieval of 12 relevant studies. Early postoperative cerebral complications include intracranial hemorrhage associated with a coexisting coagulopathy, perioperative hypertension, and higher MELD scores and is more frequent in critically ill recipients; central pontine and extrapontine myelinolysis are associated with notable perioperative changes in the plasma Na+ concentration and massive transfusion. Long-term follow-up cerebral complications include focal brain lesions, cerebrovascular diseases, and posterior reversible encephalopathy; there is no proven relationship between the toxicity immunosuppressive drugs and cerebral complications. This SR confirms a very low incidence of opportunistic cerebral infections.

Clinical Implications, Evaluation, and Management of Hyponatremia in Cirrhosis

Hyponatremia is the most common electrolyte abnormality in patients with decompensated cirrhosis on Liver Transplantation (LT) waiting list. Most of these patients have dilutional or hypervolemic hyponatremia secondary to splanchnic vasodilatation. Excessive secretion of the antidiuretic hormone also plays an important role. Hypervolemic hyponatremia is commonly associated with refractory ascites, spontaneous bacterial peritonitis, and hepatic encephalopathy. Although uncommon, the use of diuretics and laxatives can cause hypovolemic hyponatremia that is characterized by the striking absence of ascites or pedal edema. Clinical features are often nonspecific and depend on the acuity of onset rather than the absolute value of serum sodium. Symptoms may be subtle, including nausea, lethargy, weakness, or anorexia. However, rarely patients may present with confusion, seizures, psychosis, or coma. Treatment includes discontinuation of diuretics, beta-blockers, and albumin infusion. Hypertonic saline (3%) infusion may be used in patients with very low serum sodium (<110 mmol/L) or when patients present with seizures or coma. Short-term use of Vasopressin (V₂) receptor antagonists may also be used to normalize sodium levels prior to LT. However, all these measures may be futile, and LT remains the definite treatment in these patients to improve survival. In this review, we describe the classification, pathogenesis of hyponatremia, and its clinical implications in patients with cirrhosis. Approach to these patients along with management will also be discussed briefly.

Careful neurologic examination and treatment for intracranial hemorrhage after liver transplantation in patients with alcoholic cirrhosis: case reports

Intracranial hemorrhage (ICH) following liver transplantation is a potentially devastating complication. Although hypertension and thrombocytopenia are well-known risk factors for ICH in the general population, their roles in ICH after liver transplantation have not been well established. ICH occurred in two patients with alcoholic cirrhosis after deceased donor liver transplantation. A 38-year-old man presented with acute ICH in the right parietal lobe on day 16 after transplantation, with decreased level of consciousness and seizure. His mental status improved with immediate neurological treatment without surgery. In the second case, a 42-year-old woman had acute ICH in the left frontoparietal lobes on day 9 after transplantation, with generalized tonic-clonic seizures. Urgent cerebral decompression was performed. The patient’s neurological symptoms gradually recovered. In both cases, the blood platelet count was less than 50,000/mm³. Monitoring cerebral pressure for ICH is an invasive and challenging method, especially in patients with cirrhosis who have issues with hemostasis. Surgeons should be critically mindful of the risk of rapid neurological deterioration in patients with cirrhosis. Careful neurologic examination and immediate treatment to lower intracranial pressure for ICH after liver transplantation in patients with alcoholic cirrhosis are very important.

Hemodynamic Instability During Liver Transplantation in Patients With End-stage Liver Disease: A Consensus Document from ILTS, LICAGE, and SATA

Hemodynamic instability (HDI) during liver transplantation (LT) can be difficult to manage and increases postoperative morbidity and mortality. In addition to surgical causes of HDI, patient- and graft-related factors are also important. Nitric oxide-mediated vasodilatation is a common denominator associated with end-stage liver disease related to HDI. Despite intense investigation, optimal management strategies remain elusive. In this consensus article, experts from the International Liver Transplantation Society, the Liver Intensive Care Group of Europe, and the Society for the Advancement of Transplant Anesthesia performed a rigorous review of the most current literature regarding the epidemiology, causes, and management of HDI during LT. Special attention has been paid to unique LT-associated conditions including the causes and management of vasoplegic syndrome, cardiomyopathies, LT-related arrhythmias, right and left ventricular dysfunction, and the specifics of medical and fluid management in end-stage liver disease as well as problems specifically related to portal circulation. When possible, management recommendations are made.

The Role of Non-Immune Cell-Derived Extracellular Vesicles in Allergy

Extracellular vesicles (EVs), and especially exosomes, have been shown to mediate information exchange between distant cells; this process directly affects the biological characteristics and functionality of the recipient cell. As such, EVs significantly contribute to the shaping of immune responses in both physiology and disease states. While vesicles secreted by immune cells are often implicated in the allergic process, growing evidence indicates that EVs from non-immune cells, produced in the stroma or epithelia of the organs directly affected by inflammation may also play a significant role. In this review, we provide an overview of the mechanisms of allergy to which those EVs contribute, with a particular focus on small EVs (sEVs). Finally, we also give a clinical perspective regarding the utilization of the EV-mediated communication route for the benefit of allergic patients.

Evaluation of Clinical Neuropathy After Living Donor Liver Transplant

OBJECTIVES

Neurologic complications are more common in liver transplants than in other solid-organ transplants. One such neurologic complication, peripheral neuropathy, may cause functional limitations for recipients and have a negative effect on posttransplant quality of life. We aimed to examine the risk factors associated with the occurrence of clinical neuropathy after liver transplant and to investigate the frequency of sensory deficits.

MATERIALS AND METHODS

In this case-control study, we analyzed factors from medical records of 63 recipients who underwent living donor liver transplant during the period from January 2010 to December 2016. A neuropathy symptom score was assigned to identify the patients who had clinical neuropathy (case group) and the patients without clinical neuropathy (control group). Quantitative sensory testing was performed to measure the warm and cold detection thresholds, and the difference between the 2 groups was examined.

RESULTS

Compared with controls, patients with clinical neuropathy were older (61.0 vs 55.4 years; P = .028), had higher rates of diabetes (46.2% vs 16.0%; P = .03), and were taking antiviral agents against hepatitis B (100% vs 62%; P = .006). Patients with neuropathic symptoms had significantly increased frequencies of impairment of warm and cold detection thresholds. In addition, the greater severity of symptoms showed higher detection thresholds of warm (control, 40.7℃; mild-to-moderate, 43.8 ℃; severe, 46.0 ℃; P = .007) and cold (control, 28.8℃ ; mild-to-moderate, 27.0 ℃; severe, 21.8 ℃ ; P = .008).

CONCLUSIONS

Our findings show that older age, diabetes, and treatment with oral antiviral agents against hepatitis B virus were more likely to be associated with the occurrence of clinical neuropathy after liver transplant. Early awareness and careful monitoring are warranted.

Neurological complications after living-donor liver transplantation in children

AIM

Liver transplantation (LT) has been used as a definitive management for children with end-stage liver disease or acute liver failure. Living-donor LT (LDLT) has been a common type of LT performed in Asian countries, including Japan, where deceased donors are rarely available. However, the neurological complications (NCs) associated with LDLT remain unknown. The purpose of this study was to clarify the characteristics of NCs in children after LDLT.

METHODS

This study is a retrospective observational study carried out at a tertiary children's hospital in Japan. We studied children who had undergone LDLT between January 2001 and January 2020.

RESULTS

We examined 602 cases of LT, of which 559 were LDLT cases (92.9%). NCs after LT were present in 21 cases (3.8%). The most common neurological symptoms were seizure (n = 17), whereas disturbance of consciousness without seizure was observed in four cases. The frequency of NCs for each of the indications was 12.2% for fulminant hepatic failure, 6.5% for metabolic liver disease, and 0.7% for cholestatic liver disease.

INTERPRETATION

We report the characteristics of NCs after LDLT in children. The frequency of NCs after LT was high in cases of fulminant hepatic failure and metabolic diseases, who might have had neurological symptoms or impaired consciousness before LT.

Mechanical Circulatory Support Prior to Heart Transplantation Predicts Early Post-Operative Stroke

BACKGROUND

Mechanical circulatory support (MCS) devices are often deployed to treat patients with refractory cardiogenic shock, rapid deterioration of heart failure, and inotrope-dependent patients. Stroke is a common complication of MCS therapy. This study assesses the risk of stroke during the early post-heart transplantation (HT) period (days from successful HT to discharge or death) in patients who received MCS therapy leading to HT.

METHODS

Data were derived from the United Organ Sharing (UNOS) database. MCS modalities studied include left ventricular assist devices (LVAD), right ventricular assist devices (RVAD), biventricular ventricular assist devices (BiVAD), and extra-corporeal membrane oxygenation (ECMO). A multiple logistic regression model was used to determine the risk of stroke during the early post-HT period associated in patients treated with MCS leading to HT.

RESULTS

Between 1988 and 2014, 10,258 patients received MCS therapy leading to HT. Of these, 160 patients (1.96%) developed stroke during the early post-HT period. Multiple regression analysis showed that MCS modalities and associated odds ratios for early post-HT stroke and associated 95% confidence intervals were as follows: LVAD (1.44, 0.70-2.94), RVAD (2.89, 1.03-8.05, BiVAD (3.24, 1.15-9.10), ECMO (2.27 (1.17-4.40), and any MCS (1.60 (1.20-2.12).

CONCLUSIONS

With the exception of left ventricular assist devices, use of MCS modalities leading to HT is significantly and independently associated with stroke during the early post-HT period.

Tacrolimus-induced epilepsy with primary membranous nephropathy: A case report

RATIONALE

Tacrolimus-associated neurologic disorders can be found in some cases, mainly in organ transplantation patients. However, epilepsy induced by tacrolimus in primary membranous nephropathy (PMN) patient is scare.

PATIENT CONCERNS

A 63-year-old man experienced 1-year history of foamy urine, and edema of lower extremity.

DIAGNOSIS

The patient had proteinuria, hypoalbuminemia, which indicated nephrotic syndrome. Further, we performed renal biopsy for this patient. Combined with the renal biopsy result, the diagnosis of primary membranous nephropathy was established.

INTERVENTION

At first, irbesartan was administrated for 6 months. However, the proteinuria had no obvious improvement. Tacrolimus was administrated afterwards.

OUTCOMES

Twenty-two days after tacrolimus treatment, epilepsy occurred. Sodium valproate and carbamazepine were successively given to control epilepsy. However, the epileptic symptoms were not effectively controlled. During the treatment, the concentration of tacrolimus fluctuated greatly. At last, levetiracetam was given to maintain the curative effect. Fortunately, the patient did not suffer from epilepsy again. The concentration of temporary tacrolimus was stable, whereas proteinuria gradually decreased.

LESSONS

Tacrolimus-induced epilepsy should be considered in patients exhibiting acute neurological symptoms. Early diagnosis and effective treatment play a vital role for favorable prognosis.

Association between donor/recipient MTRR gene polymorphisms and the risk of new-onset neurological complications after liver transplantation

Neurological complications are very common after liver transplantation. This study focuses on clinical risk factors and susceptibility gene polymorphisms of neurological complications after liver transplantation. A better predictive model is obtained. This study proves that MTRR is an independent susceptibility gene for neurological complications. Compared with the independent risk factor of abdominal infection, MTRR has a more advantageous value in predicting neurological complications after liver transplantation.

Hyponatremia in Cirrhosis: An Update

Hyponatremia is frequently seen in patients with ascites secondary to advanced cirrhosis and portal hypertension. Although not apparent in the early stages of cirrhosis, the progression of cirrhosis and portal hypertension leads to splanchnic vasodilation, and this leads to the activation of compensatory mechanisms such as renin-angiotensin-aldosterone system (RAAS), sympathetic nervous system, and antidiuretic hormone (ADH) to ameliorate low circulatory volume. The net effect is the avid retention of sodium and water to compensate for the low effective circulatory volume, resulting in the development of ascites. These compensatory mechanisms lead to impairment of the kidneys to eliminate solute-free water in decompensated cirrhosis. Nonosmotic secretion of antidiuretic hormone (ADH), also known as arginine vasopressin, further worsens excess water retention and thereby hyponatremia. The management of hyponatremia in this setting is a challenge as conventional therapies for hyponatremia including fluid restriction and correction of hypokalemia are frequently inefficacious. In this review, we discuss the pathophysiology, complications, and various treatment modalities, including albumin infusion, selective vasopressin receptor antagonists, or hypertonic saline for patients with severe hyponatremia and those awaiting liver transplantation.

Prevalence of cerebrovascular diseases that can cause hemorrhagic stroke in liver transplantation recipients: a 6-year comparative study with 24,681 healthy adults

BACKGROUND AND PURPOSE

Cerebrovascular diseases are a leading cause of mortality after liver transplantation (LT). The prevalence of potentially hemorrhagic cerebrovascular diseases (HCVDs) that could cause a hemorrhagic stroke in patients with severe liver diseases has not been reported. We aimed to analyze the underlying prevalence of HCVDs that could lead to hemorrhagic strokes in LT recipients compared with that in previously healthy controls.

METHODS

A retrospective study with 1,920 consecutive LT recipients and 24,681 adults who underwent a health checkup during the same period was conducted (January 2011-December 2016). The prevalence of cerebral aneurysms (CA), cerebral arteriovenous malformation (AVM), and cavernous malformation (CM) was evaluated using brain imaging, including computed tomography angiography, magnetic resonance imaging, magnetic resonance angiography, and digital subtraction angiography.

RESULTS

The prevalence of CA and CM were 3.1% and 0.5%, respectively, in the LT group and 3.8% and 0.4%, respectively, in the control group. According to the location of the cerebral artery, paraclinoid internal carotid artery aneurysms (odds ratio [OR] 0.440; P = 0.009) had a lower prevalence in LT recipients than in healthy controls. Anterior communicating artery (OR 3.080; P = 0.002) and superior cerebellar artery (OR 8.767; P = 0.017) aneurysms had a higher prevalence in the LT group than in the control. The prevalence of AVM was significantly higher in LT recipients (0.26%) than in healthy controls (0.06%).

CONCLUSION

LT recipients showed a different distribution of CA prevalence according to the locations of the cerebral artery and had a higher overall prevalence of AVM than previously healthy controls.

Can osmotic demyelination syndrome be a complication of liver failure?

This case demonstrates that osmotic demyelination syndrome (ODS) can occur in absence of hyponatremia in patients with fulminant liver failure and markedly high bilirubin levels. Extremely high bilirubin levels, such as >900 μmol/L in the case presented here, may lead to blood brain barrier dysfunction by disrupting blood vessel endothelial cell function as well as increase the release of inflammatory cytokines. As demonstrated in the case here, even small fluctuations in electrolytes may make the brain increasingly more vulnerable to ODS. Clinicians should keep ODS high on their differential even in eunatremic patients with liver failure who have decreased levels of consciousness or coma.

Elevation of Preoperative Ammonia Level Is Not Associated With the Incidence of Postoperative Delirium in Patients with Liver Transplantation: A Propensity Score Matching Analysis

INTRODUCTION

The preoperative elevation of ammonia may be associated with postoperative neurologic complications. The aim of this study was to evaluate the effect of preoperative ammonia level on the incidence of delirium in patients after liver transplantation (LT).

MATERIALS AND METHODS

Patients (n = 260) who received LT from January 2010 to July 2017 in a single university hospital were retrospectively reviewed. The patients' demographic data, perioperative managements, and postoperative complications were assessed. Patients were divided into the following 2 groups: those who had a preoperative elevation (Group A, n = 158) and those with a normal range (Group C, n = 102). The cut-off value for a normal serum ammonia level in our hospital was defined as 32 μg/dL.

RESULTS

After propensity score matching, there was no difference in the incidence of delirium between the groups (P = .784). Delirium occurred in 8 of 68 (11.76%) patients in Group A and 7 of 68 (10.29%) patients in Group C after LT. In addition, there was no difference in the incidence of delirium between the groups, even patients were categorized based on serum ammonia levels into 3 groups as follows: < 32 μg/dL (28/158 [17.72%]), 32 to 65 μg/dL (28/158 [17.72%]), and >65 μg/dL (28/158 [17.72%]) (P = .134).

CONCLUSIONS

The preoperative serum ammonia level was not related with the incidence of postoperative delirium. The high elevation group, especially those with greater than 65 μg/dL of preoperative ammonia, was also not related with the incidence of delirium. However, our study is limited by its retrospective design, so future prospective studies are needed.

Exosomes Mediate Hippocampal and Cortical Neuronal Injury Induced by Hepatic Ischemia-Reperfusion Injury through Activating Pyroptosis in Rats

Background

The neuronal injury and cognitive dysfunction after liver transplantation have severe effects on the prognosis and life quality of patients. Accumulating evidence suggests that both exosomes and pyroptosis could participate in hepatic ischemia-reperfusion injury (HIRI) and play key roles in neuronal death. However, the link between exosomes and neuronal pyroptosis in HIRI awaits further investigation.

Methods

After establishing the HIRI rat models, we primarily studied the role of pyroptosis in hippocampal and cortical neuron injury through detecting NOD-like receptor protein 3 (NLRP3), pro-caspase-1, cleaved-caspase-1, apoptosis-associated speck-like protein containing CARD (ASC), gasdermin D (GSDMD), interleukin-1beta (IL-1β), and interleukin-18 (IL-18) expressions with western blotting, immunohistochemical staining, and enzyme-linked immunosorbent assay (ELISA). Then, we intravenously injected normal male rats with exosomes isolated from the sera of HIRI-challenged rats and pretreated rats with MCC950, a specific inhibitor of NLRP3, and carried out the same assay. We also detected the levels of reactive oxygen species (ROS), superoxide dismutase (SOD), and malondialdehyde (MDA) in the hippocampal and cortical tissues.

Results

The results indicated that NLRP3 inflammasome and caspase-1-dependent pyroptosis were activated in the hippocampus and cortex of HIRI rats. Furthermore, serum-derived exosomes from HIRI-challenged rats not only had the ability to cross the blood-brain barrier (BBB) but also had the similar effects on neuronal pyroptosis. Moreover, ROS and MDA productions were induced in the HIRI and exosome-challenged groups. In addition, to some degree, MCC950 could alleviate HIRI-mediated hippocampal and cortical neuronal pyroptosis.

Conclusion

This study experimentally demonstrated that circulating exosomes play a critical role in HIRI-mediated hippocampal and cortical injury through regulating neuronal pyroptosis.

Neurologic Complications of Transplantation

Neurologic disturbances including encephalopathy, seizures, and focal deficits complicate the course 10-30% of patients undergoing organ or stem cell transplantation. While much or this morbidity is multifactorial and often associated with extra-cerebral dysfunction (e.g., graft dysfunction, metabolic derangements), immunosuppressive drugs also contribute significantly. This can either be through direct toxicity (e.g., posterior reversible encephalopathy syndrome from calcineurin inhibitors such as tacrolimus in the acute postoperative period) or by facilitating opportunistic infections in the months after transplantation. Other neurologic syndromes such as akinetic mutism and osmotic demyelination may also occur. While much of this neurologic dysfunction may be reversible if related to metabolic factors or drug toxicity (and the etiology is recognized and reversed), cases of multifocal cerebral infarction, hemorrhage, or infection may have poor outcomes. As transplant patients survive longer, delayed infections (such as progressive multifocal leukoencephalopathy) and post-transplant malignancies are increasingly reported.

A 41-year-old female with progressive multifocal leukoencephalopathy after liver transplant

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease caused by JC virus reactivation. Its occurrence is very rare after solid organ transplantation, especially liver transplantation. We report a patient who received liver transplantation due to liver failure resulting from autoimmune hepatitis and advanced PML presenting with aphasia. A 41-year-old female with a history of liver transplantation who received a usual immunosuppression regimen was admitted with a stroke attack resulting in right hemiplegia 2 months after liver transplantation. Surprisingly, she gradually developed dysarthria and left central facial paresis. A brain MRI showed an abnormal multifocal area with a high T2/flair signal in the deep subcortical white matter of the left hemisphere as well as the splenium of the corpus callosum. PCR evaluation of CSF for JCV was positive while other PCR results were negative. A liver transplant recipient receiving immunosuppressive treatment for a long time could develop PML due to JCV reactivation. Only eight cases of JCV infection were reported after liver transplantation by the time of reporting this case. Unfortunately, there is no definite treatment for PML.

Cognitive impairment after liver transplantation: residual hepatic encephalopathy or posttransplant encephalopathy?

Liver transplantation (LT) represents the definitive treatment for end-stage liver disease. Cognitive impairment following LT is frequent, referred to as postliver transplant encephalopathy (PLTE). LT removes the underlying chronic liver disease, and until recently hepatic encephalopathy (HE) was assumed to be fully reversible after LT. However, increasing evidence indicates that some degree of cognitive impairment may be present after LT. To which extent PLTE reflects cognitive impairment caused by residual HE (RHE) or the combined effect of other factors affecting brain function before, during, and after LT is not clarified. None of the available psychometric and neurophysiological tests used for detecting HE is shown to be able to distinguish between etiologies. The available, mostly retrospective, clinical studies indicate a high prevalence of abnormal psychometric tests after LT, and not all seem to recover completely. The patients with earlier HE show the most marked improvements, suggesting that the clinical picture of the early PLTE, in fact, represents RHE. Other early post-LT etiologies for PLTE comprise cerebral ischemia, critical illness encephalopathy, and immunosuppressive therapy. Late-onset etiologies comprise diabetes and hypertension, among others. PLTE regardless of etiology is a worrying issue and needs more attention in the form of mechanistic research, development of diagnostic/discriminative tools, and standardized prospective clinical studies.

Neurological Complications Occurring After Liver Transplantation: Role of Risk Factors, Hepatic Encephalopathy, and Acute (on Chronic) Brain Injury

Orthotopic liver transplantation (LT) remains the only way to definitively cure patients with the most severe liver diseases. Because the survival rate is now fairly high, important questions about neurological sequelae or quality of life after LT have emerged. Indeed, LT represents a peculiar situation because up to 30% of patients present with neurological symptoms after LT compared with only 4% after cardiac transplant and 0.5% after renal transplant. These postoperative neurological symptoms have long been interpreted as sequelae of hepatic encephalopathy (HE). However, postoperative decompensation of an unknown cerebral condition due to the pathophysiology of cirrhosis or undiagnosed neurodegenerative disorders or aging constitute other possibilities that are underrecognized. Some patients who undergo LT for acute liver failure and patients with cirrhosis without episodes of HE and without any previous cerebral alteration also display post-LT neurological symptoms. This latter situation speaks in favor of a direct adverse effect of either general anesthesia, the surgical procedure, or factors related to the postoperative intensive care unit (ICU) environment. The role of inflammation, which has been described in the ICU setting, could also be a crucial determinant. In this review, we will discuss the neurological complications associated with LT, the neurocognitive complications after LT, and how to assess the LT-related neurological or neurocognitive complications. Furthermore, we will review the various hypotheses surrounding post-LT neurocognitive impairment and will conclude with recommendations for future directions.

Hyponatremia in Cirrhosis: Implications for Liver Transplantation

Hyponatremia in cirrhosis is defined as a serum sodium level ≤130 mEq/L and occurs in approximately 22% of patients with cirrhosis. The appearance of hyponatremia in patients with cirrhosis portends a poor prognosis before liver transplantation (LT), independent of the Model for End-Stage Liver Disease (MELD) score. With the development of the MELD-sodium score, the management of hyponatremia has become more relevant than ever before. Overcorrection of hyponatremia before LT or perioperatively can lead to the devastating neurologic condition known as osmotic demyelination syndrome, which is often irreversible and fatal. Therefore, the most important tenet of hyponatremia is to avoid correcting the serum sodium by ≥8 mEq/L in a 24-hour period. Treatment of hyponatremia is highly challenging. The vast majority of patients with cirrhosis have chronic hypervolemic hyponatremia. Fluid restriction increases serum sodium levels, but tolerance and compliance are significant barriers. Diuretic withdrawal is helpful but contributes to worsening fluid overload. There are limited data to support use of intravenous concentrated albumin solutions. The use of the arginine vasopressin antagonists ("vaptans") is contentious; however, they may have a limited role. Risk factors for intraoperative overcorrection of serum sodium include increased utilization of packed red blood cell and fresh frozen plasma transfusions, which are often unavoidable. Intraoperative management is evolving, and more data are needed in regard to the use of sodium-reduced continuous venovenous hemofiltration and the use of trishydroxymethylaminomethane (Tris) to avoid excess sodium rebound. A thorough discussion of the current treatment options before and during LT is given in this review.

Complications of Solid Organ Transplantation: Cardiovascular, Neurologic, Renal, and Gastrointestinal

Despite improvements in overall graft function and patient survival rates after solid organ transplantation, complications can lead to significant morbidity and mortality. Cardiovascular complications include heart failure, arrhythmias leading to sudden death, hypertension, left ventricular hypertrophy, and allograft vasculopathy in heart transplantation. Neurologic complications include stroke, posterior reversible encephalopathy syndrome, infections, neuromuscular disease, seizure disorders, and neoplastic disease. Acute kidney injury occurs from immunosuppression with calcineurin inhibitors or as a result of graft failure after kidney transplantation. Gastrointestinal complications include infections, malignancy, mucosal ulceration, perforation, biliary tract disease, pancreatitis, and diverticular disease. Immunosuppression can predispose to infections and malignancy.

Mycobacterium tuberculosis after solid organ transplantation: A review of more than 2000 cases

BACKGROUND

Mycobacterium tuberculosis (TB) is a common pathogen worldwide, and it may cause significant infection after solid organ transplantation (SOT). We reviewed all reported TB cases to provide an update on its epidemiology, clinical presentation, management, and outcome after SOT.

METHODS

MEDLINE, EMBASE, and OVID were reviewed from January 1, 1998, to December 31, 2016, using keywords tuberculosis and solid organ transplant or transplantation.

RESULTS

There were 187 publications reporting 2082 cases of TB among kidney (n = 1719), liver (n = 253), heart (n = 77), lung (n = 25), and kidney-pancreas (n = 8) recipients. Among cohort studies, the median incidence was 2.37% (range, 0.05%-13.27%) overall. Most TB disease was considered reactivation of latent infection, occurring beyond the first year after SOT. Early-onset cases were seen among donor-derived TB cases. Fever was the most common symptom. Radiologic findings were highly variable. Extrapulmonary and disseminated TB occurred 29.84% and 15.96%, respectively. Multidrug-resistant TB was rare. Treatment using 4 or 5 drugs was commonly associated with hepatotoxicity and graft dysfunction. All-cause mortality was 18.84%.

CONCLUSIONS

This large review highlights the complexity of TB after SOT. Reactivation TB, donor-transmitted infection, extrapulmonary involvement, and disseminated disease are common occurrences. Treatment of TB is commonly associated with hepatotoxicity and graft dysfunction.

Incidence, risk factors, and outcomes related with neurological events after liver transplantation in adult and pediatric recipients

Controversy exists whether NE after LT are more frequently observed in children or adults. We aimed to compare the incidence and outcomes for NE after LT in pediatric and adult recipients. A single-center cohort study, including all LT between 2001 and 2013, was performed. Definition of NE included impaired consciousness, delirium, seizures, focal neurologic deficit, visual impairment, or slurred speech. A cohort of 443 consecutive LT recipients was included: 307 adults and 136 children. Cumulative incidence of NE was similar between adults 15% (n = 41) and children 16% (n = 20; P = .73) with a complete neurological recovery in 62% and 95% of the patients, respectively (P < .0001). Adults with NE had significantly lower survival (70% vs 76%; P = .015) with a HR of 2.36; this was similarly observed in children (45% vs 66%; HR 2.05, CI 0.66; 6.34). Independent risk factors for NE in adults were pre-LT ascites, delta sodium, and post-LT hypomagnesemia, whereas in children pre-LT encephalopathy ≥II and serum albumin were associated with NE. Although a similar incidence of NE after LT was observed, children were more likely to achieve neurological recovery. Risk factors for the development of NE are difficult to assess in both populations.

Prevention of the Osmotic Demyelination Syndrome After Liver Transplantation: A Multidisciplinary Perspective

The osmotic demyelination syndrome (ODS) is a serious neurologic condition that occurs in the setting of rapid correction of hyponatremia. It presents with protean manifestations, from encephalopathy to the "locked-in" syndrome. ODS can complicate liver transplantation (LT), and its incidence may increase with the inclusion of serum sodium as a factor in the Mayo End-Stage Liver Disease score. A comprehensive understanding of risk factors for the development of ODS in the setting of LT, along with recommendations to mitigate the risk of ODS, are necessary. The literature to date on ODS in the setting of LT was reviewed. Major risk factors for the development of ODS include severe pretransplant hyponatremia (serum sodium [SNa] < 125 mEq/L), the magnitude of change in SNa pre- versus posttransplant, higher positive intraoperative fluid balance, and the presence of postoperative hemorrhagic complications. Strategies to reduce the risk of ODS include correcting hyponatremia pretransplant via fluid restriction and/or ensuring an appropriate rate of increase from the preoperative SNa via close attention to fluid and electrolyte management both during and after surgery. Multidisciplinary management involving transplant hepatology, nephrology, neurology, surgery, and anesthesiology/critical care is key to performing LT safely in patients with hyponatremia.

JC Virus-Related Progressive Multifocal Leukoencephalopathy After Living-Donor Liver Transplant: A Rare Case

Progressive multifocal leukoencephalopathy caused by polyoma JC virus is a rare and severe demyelinating disease of the central nervous system. It occurs in immunocompromised patients and is scarcely reported in liver transplant recipients. Brain biopsy demonstrating demyelination with presence of foamy macrophages, relative preservation of axons, astrogliosis, and typical polyomavirus inclusions in the enlarged oligodendroglial nuclei is essential for diagnosis. Here, we report a case of JC virus-associated progressive multifocal leukoencephalopathy in a living-donor liver transplant recipient who was transplanted for hepatitis C virus-related decompensated cirrhosis. Brain biopsy with immunohistochemistry confirmed the diagnosis of progressive multifocal leukoencephalopathy secondary to JC virus. JC virus related-progressive multifocal leukoencephalopathy is associated with extremely poor prognosis. Awareness and consideration of this entity in liver transplant recipients who present with sudden progressive neurologic manifestations can help in prompt diagnosis and timely treatment.

Immediate postoperative management and complications on the intensive care unit

The postoperative management of patients immediately after liver transplantation requires knowledge of this complex surgery and the physiology that accompanies liver failure. A multidisciplinary approach to the care of these patients is essential in order to reduce postoperative complications and preserve function in the transplanted organ. By their nature, patients undergoing liver transplantation have complicated medical problems before surgery which must be borne in mind when managing them after surgery. Haemorrhage, haemodynamic instability, acute renal failure, hepatic artery thrombosis and primary graft non-function are some of the complications that clinicians must be prepared for in the first days after transplantation. Pre-empting complications and acting rapidly to overt them is likely to have a considerable positive impact in these patients.

Early and late neurological complications of liver transplantation in pediatric patients

NCs occur commonly after solid organ transplantation and affect 15%-30% of liver transplant recipients. The aim of this retrospective study was to evaluate the type and incidence of neurologic events in pediatric patients following LT. Between May 2006 and June 2015, 242 patients (118 females, 124 males) requiring LT for different etiologies at the İnönü University Liver Transplantation Institute were included. The incidence, types, and risk factors of NCs that occurred following LT were evaluated retrospectively. Neurologic events occurred in 57 (23.5%) of the patients. Early NCs were encephalopathy (12.4%), seizures (11.5%), and PRES (7%). Of 57 patients, five (8.7%) experienced NCs at least 1 month after LT; these late NCs included tremor, headaches, encephalopathy, ataxia, and neuropathy. The psychiatric symptoms after LT were noted in 42 patients (17.4%). The mortality rate after LT in those with or without neurological events was not significantly different (P=.73). There was a high incidence of serious neurologic events after LT. The major neurologic manifestation in our patients was encephalopathy followed by seizures.

Neurologic complications of transplantation

Major neurologic morbidity, such as seizures and encephalopathy, complicates 20-30% of organ and stem cell transplantation procedures. The majority of these disorders occur in the early posttransplant period, but recipients remain at risk for opportunistic infections and other nervous system disorders for many years. These long-term risks may be increasing as acute survival increases, and a greater number of "sicker" patients are exposed to long-term immunosuppression. Drug neurotoxicity accounts for a significant proportion of complications, with posterior reversible leukoencephalopathy syndrome, primarily associated with calcineurin inhibitors (i.e., cyclosporine and tacrolimus), being prominent as a cause of seizures and neurologic deficits. A thorough evaluation of any patient who develops neurologic symptoms after transplantation is mandatory, since reversible and treatable conditions could be found, and important prognostic information can be obtained.

Intracranial hemorrhage induced uncontrolled seizure in a deceased donor liver transplant patient: a case report

Seizure is the second most common neurologic complication after liver transplantation and may be caused by metabolic abnormalities, electrolyte imbalance, infection, and immunosuppressant toxicity. A 61-year-old male patient underwent liver transplantation due to hepatitis B virus-related liver cirrhosis with portal systemic encephalopathy. The immediate postoperative course of the patient was uncomplicated. However, on postoperative day (POD) 6, weakness developed in both lower extremities. No abnormal findings were detected on a brain computed tomography (CT) scan on POD 8, but a generalized tonic clonic seizure developed which was difficult to control even with multiple antiepileptic drugs. A follow-up brain CT scan on POD 15 showed a 2.7 cm sized acute intracranial hemorrhage (ICH) in the left parietal lobe. The patient's mental status improved after 2 months and he was able to communicate through eye blinking or head shaking. Our case reports an acute ICH that manifested into a refractory seizure in a patient who underwent a liver transplant.