Acquired hepatocerebral degeneration: clinical characteristics and MRI findings

Trace Element Imbalances in Acquired Hepatocerebral Degeneration and Changes after Liver Transplant

Brain manganese (Mn) accumulation is a key feature in patients with acquired hepatocerebral degeneration (AHD). The role of trace elements other than Mn in AHD needs to be clarified. In this study, using inductively coupled plasma mass spectrometry, we aimed to evaluate blood levels of trace elements in patients with AHD before and after liver transplantation (LT). Trace element levels in the AHD group were also compared with those of healthy controls (blood donors, n = 51). Fifty-one AHD patients were included in the study (mean age: 59.2 ± 10.6 years; men: 72.5%). AHD patients had higher levels of Mn, Li, B, Ni, As, Sr, Mo, Cd, Sb, Tl and Pb and a higher Cu/Se ratio, and lower levels of Se and Rb. Six patients (two women; mean age 55 ± 8.7 years) underwent LT, and there was an improvement in neurological symptoms, a significant increase in the Zn, Se and Sr levels, and a decrease in the Cu/Zn and Cu/Se ratios. In summary, several trace element imbalances were identified in AHD patients. Liver transplantation resulted in the improvement of neurological manifestations and the oxidant/inflammatory status. It is possible that observed changes in trace element levels may play a role in the pathophysiology and symptomatology of AHD.

Treatable Ataxias: How to Find the Needle in the Haystack?

Treatable ataxias are a group of ataxic disorders with specific treatments. These disorders include genetic and metabolic disorders, immune-mediated ataxic disorders, and ataxic disorders associated with infectious and parainfectious etiology, vascular causes, toxins and chemicals, and endocrinopathies. This review provides a comprehensive overview of different treatable ataxias. The major metabolic and genetic treatable ataxic disorders include ataxia with vitamin E deficiency, abetalipoproteinemia, cerebrotendinous xanthomatosis, Niemann-Pick disease type C, autosomal recessive cerebellar ataxia due to coenzyme Q10 deficiency, glucose transporter type 1 deficiency, and episodic ataxia type 2. The treatment of these disorders includes the replacement of deficient cofactors and vitamins, dietary modifications, and other specific treatments. Treatable ataxias with immune-mediated etiologies include gluten ataxia, anti-glutamic acid decarboxylase antibody-associated ataxia, steroid-responsive encephalopathy associated with autoimmune thyroiditis, Miller-Fisher syndrome, multiple sclerosis, and paraneoplastic cerebellar degeneration. Although dietary modification with a gluten-free diet is adequate in gluten ataxia, other autoimmune ataxias are managed by short-course steroids, plasma exchange, or immunomodulation. For autoimmune ataxias secondary to malignancy, treatment of tumor can reduce ataxic symptoms. Chronic alcohol consumption, antiepileptics, anticancer drugs, exposure to insecticides, heavy metals, and recreational drugs are potentially avoidable and treatable causes of ataxia. Infective and parainfectious causes of cerebellar ataxias include acute cerebellitis, postinfectious ataxia, Whipple's disease, meningoencephalitis, and progressive multifocal leukoencephalopathy. These disorders are treated with steroids and antibiotics. Recognizing treatable disorders is of paramount importance when dealing with ataxias given that early treatment can prevent permanent neurological sequelae.

Acquired Hepatocerebral Degeneration After a Splenorenal Shunt in the Sub-Saharan Africa Context: A Case Report and Brief Review of Literature

Acquired hepatocerebral degeneration (AHD) is a neurologic syndrome caused by liver dysfunction and long-standing portosystemic shunting. The pathogenesis of the condition is predominantly considered to be related to the deposition of manganese in parts of the brain due to shunting. We report a case of a 25-year-old male who underwent splenectomy and splenorenal shunt for recurrent upper GI bleeding (UGIB) due to esophageal varices caused by non-cirrhotic portal hypertension (NCPH). He presented with bradykinesia, hypophonia, gait instability, and rigidity of the lower extremities 18 months after the procedure was done.

Clinical Reasoning: A Middle-aged Man With Progressive Gait Abnormalities

Progressive spastic paraplegia is the core symptom of hereditary spastic paraplegias (HSPs), a group of monogenic disorders characterized pathologically by degeneration of the corticospinal tract and dorsal column and leading to irreversible neurologic deficits. However, acquired causes, such as structural, vascular, inflammatory, infectious, metabolic, toxic, neurodegenerative, and iatrogenic causes, can also cause acquired spastic paraplegia. We describe the case of a middle-aged man presenting with progressive spastic paraplegia combined with ataxia and parkinsonism. No mutation of HSP genes was detected. After a comprehensive diagnostic workup, hyperintensities in the bilateral basal ganglia, mesencephalon, pons, and cerebellum on T1-weighted images were found, which demonstrated hypointensity on susceptibility-weighted imaging. Furthermore, an increased blood ammonia level and diffuse slow-wave activity in EEG were detected. The patient had a 7-year history of hypertension, alcoholic liver cirrhosis, and transjugular intrahepatic portosystemic shunt operation 2 years before the onset of spastic paraplegia symptoms. Current workup combined with patient history resulted in a diagnosis of acquired hepatocerebral degeneration and hepatic myelopathy.. This case provided a detailed diagnostic approach for progressive spastic paraplegias and exhaustive differential diagnoses of basal ganglia deposits. The take-home message from this case was that acquired causes, especially curable causes, should always be excluded first when dealing with patients with progressive spastic paraplegia.

Magnetism of materials: theory and practice in magnetic resonance imaging

All substances exert magnetic properties in some extent when placed in an external magnetic field. Magnetic susceptibility represents a measure of the magnitude of magnetization of a certain substance when the external magnetic field is applied. Depending on the tendency to be repelled or attracted by the magnetic field and in the latter case on the magnitude of this effect, materials can be classified as diamagnetic or paramagnetic, superparamagnetic and ferromagnetic, respectively. Knowledge of type and extent of susceptibility of common endogenous and exogenous substances and how their magnetic properties affect the conventional sequences used in magnetic resonance imaging (MRI) can help recognize them and exalt or minimize their presence in the acquired images, so as to improve diagnosis in a wide variety of benign and malignant diseases. Furthermore, in the context of diamagnetic susceptibility, chemical shift imaging enables to assess the intra-voxel ratio between water and fat content, analyzing the tissue composition of various organs and allowing a precise fat quantification. The following article reviews the fundamental physical principles of magnetic susceptibility and examines the magnetic properties of the principal endogenous and exogenous substances of interest in MRI, providing potential through representative cases for improved diagnosis in daily clinical routine.

Acquired hepatocerebral degeneration in a metastatic neuroendocrine tumor long-term survivor — an update on neuroendocrine neoplasm’s treatment: A case report

BACKGROUND

Metastatic small bowel low-grade neuroendocrine tumors (NETs) have a good prognosis. Surgery is the only curative treatment; however, this may induce advanced liver disease, particularly in long-term survivor patients. Acquired hepatocerebral degeneration or Parkinsonism in cirrhosis is characterized by rapidly progressive extrapyramidal symptoms in patients with advanced liver disease.

CASE SUMMARY

A 70-year-old man presented to the emergency department with diminished consciousness and disorientation, and was diagnosed with hepatic encephalopathy. The patient was diagnosed in 1993 with a metastatic small bowel NET, for which he twice underwent hepatic surgery, with metastatic resection in 1993 and a right hepatectomy in 2002 to remove two hepatic metastases. In 2003, the patient started first-line chemotherapy and in 2004 started the first of three consecutive biological treatments, followed by radio-molecular therapy, achieving stable disease for 14 years. Disease progression was identified and he underwent an endoscopic retrograde cholangiopancreatography. However, in 2019 advanced liver disease was identified. We diagnosed the development of acquired hepatocerebral degeneration, an unusual long-term side effect after multiple hepatic procedures.

CONCLUSION

The importance of regular and ongoing surveillance in long-term NET survivors who undergo hepatic procedures should be integrated into the therapeutic management plan, as some of these negative outcomes could be prevented.

Manganese and Movement Disorders: A Review

Scientific and technological advances achieved with industrial expansion have led to an ever-increasing demand for heavy metals. This demand has, in turn, led to increased contamination of soil, water and air with these metals. Chronic exposure to metals may be detrimental not only to occupational workers but also to the nonoccupational population exposed to these metals. Manganese (Mn), a commonly used heavy metal, is an essential cofactor for many enzymatic processes that drive biological functions. However, it is also a potential source of neurotoxicity, particularly in the field of movement disorders. The typical manifestation of Mn overexposure is parkinsonism, which may be difficult to differentiate from the more common idiopathic Parkinson’s disease. In addition to environmental exposure to Mn, other potential etiologies causing hypermanganesemia include systemic health conditions, total parenteral nutrition and genetic mutations causing Mn dyshomeostasis. In this review, we critically analyze Mn and discuss its sources of exposure, pathophysiology and clinical manifestations. We have highlighted the global public health impact of Mn and emphasize that movement disorder specialists should record a detailed social and occupational history to ensure that a toxic etiology is not misdiagnosed as a neurodegenerative disease. In the absence of a definite therapeutic option, early diagnosis and timely institution of preventive measures are the keys to managing its toxic effects.

A Prospective Study of the Prevalence of Parkinsonism in Patients With Liver Cirrhosis

Acquired hepatocerebral degeneration refers to a neurological syndrome consisting of various movement disorders and cognitive impairment in advanced liver cirrhosis or portosystemic shunt. Neurological signs and symptoms may be attributed to the accumulation of toxic substances in the brain. The most common neurological presentation of this is parkinsonism. Our prospective study aimed to investigate the prevalence of parkinsonism in patients with cirrhosis who were evaluated for liver transplant and to identify any correlation between findings on brain magnetic resonance imaging (MRI) and severity of parkinsonism. Of the 120 enrolled participants with liver cirrhosis, 62 (52%) exhibited signs of parkinsonism and all had MRI basal ganglia hyperintensity. Eighteen patients from this group were transplanted and showed statistically significant improvements in their Unified Parkinson's Disease Rating Scale (UPDRS) scores. Conclusion: The data suggest the reversibility of the neurological impairment seen in cirrhosis, and therefore the effectiveness of transplantation in improving parkinsonian symptoms. There was no correlation between severity of MRI findings and clinical motor UPDRS part III. Laboratory findings showed no correlation among the abnormal levels, MRI brain signal abnormality, or UPDRS scores.

Manganese, a Likely Cause of 'Parkinson's in Cirrhosis', a Unique Clinical Entity of Acquired Hepatocerebral Degeneration

With idiopathic Parkinson's disease being a common entity, parkinsonism in acquired hepatocerebral degeneration (AHD) in the context of Manganese (Mn) has gained importance in recent years. An insight into the pathomechanisms behind this disease has been put forth. How can Mn as a divalent metal exert its effect in leading to chronic neurodegenerative disorder? Secondary to decreased excretion in liver cirrhosis, Mn significantly alters the striatal dopaminergic system. Management of this debilitating disease also focuses on different aspects where Mn has been involved in the pathogenesis. We have put forth the details behind Mn effects in Parkinson’s, which will be a guide for better understanding and management of this disease.

A literature search was performed using PubMed as a sole database, and all the articles were peer-reviewed. The author tried to follow the PRISMA guidelines. Inclusion criteria were set for 10 years, with most studies with in the last seven years. All types of study designs were included relevant to the topic, clearly delineating the pathomechanisms of Mn in the disease and also its management. After extensive research, through the PubMed database, we found that Parkinson's disease is one of the neurological complications in advanced liver cirrhosis. Mn is an essential element behind its pathogenesis; it works at different cellular levels to promote neurotoxicity. From its influx to its effects on dopamine transporters (DAT), where it disrupts dopamine homeostasis also altering postsynaptic dopamine (D2) receptors, it disrupts mitochondria and the endoplasmic reticulum (ER) promotes oxidative stress and neuroinflammation. Misfolding of alpha-synuclein (α-Syn) is promoted on chronic exposure to Mn where α-Syn from being neuroprotective becomes neurotoxic. It also alters glutaminergic and gabaergic neurotransmission. In a nutshell, the diversity of its effect on nigrostriatal denervation is challenging. The importance of neuroimaging and various approaches to management is also discussed. AHD, an uncommon entity in advanced liver cirrhosis, needs more awareness so that it can be diagnosed earlier and better therapeutic options can be sought. Our study highlighted Mn mechanisms behind this clinical entity, putting forth grounds for a better understanding of this disease. Advanced research targeting Mn for managing this disease will be revolutionary.

Atypical neuroimaging findings in patients with acquired hepatocerebral degeneration

BACKGROUND

Acquired hepatocerebral degeneration (AHD) is now widely recognized by physicians. Although hyperintensity in the bilateral globus pallidus in T1-weighted magnetic resonance images (MRIs) are characteristic neuroimaging findings, accumulating reports indicate that atypical neuroimaging findings are not rare. This study aimed to describe the spectrum of atypical neuroimaging findings and related factors in patients with AHD.

METHODS

From February 2017 to January 2019, a retrospective study was conducted of 28 patients with AHD in the Shengjing Hospital of China Medical University. The neurological manifestations, clinical parameters, and biochemical and neuroimaging findings were analyzed.

RESULTS

Among 28 patients, 14 patients were diagnosed with viral hepatitis-caused hepatocirrhosis, which was the most common cause of AHD. Resting tremor, cognitive impairment, and parkinsonian gait were the most common neurologic symptoms. Bilateral globus pallidus T1-weighted hyperintensity was detected in 26 patients (26/28, 92.9%). Ten patients (10/28, 35.7%) were determined to have an atypical neuroimaging finding. Binary logistic regression analysis indicated that age at onset of neurologic symptoms (odds ratio = 1.29, 95% confidence interval [CI] 1.03-1.61; p = 0.030) and Child-Pugh scores (odds ratio = 2.52, 95% CI, 1.01-6.31; p = 0.048) were independently associated with atypical neuroimaging findings in AHD.

CONCLUSION

The clinical manifestations of AHD are diverse; resting tremor, cognitive impairment, and parkinsonian gait were the most common. More than one third of patients had atypical neuroimaging findings. Age at onset of neurologic symptoms and Child-Pugh scores may be important predictors of atypical neuroimaging findings in patients with AHD.

Uncommon Movement Disorders in Chronic Hepatic Disease with Response to Rifaximin

Background

Chronic hepatic disease can present with extrapyramidal symptoms. We describe two cases that presented with highly unusual movement disorders: ballism and gait freezing.

Case report

Patient 1 is a 42-year-old man with previous episodes of hepatic encephalopathy (HE) who presented with upper limb dystonia and generalized chorea that progressed to ballism. Patient 2 is a 55-year-old woman who presented with pronounced gait freezing. In both patients, features of HE and acquired hepatocerebral degeneration coexisted. They improved markedly, though transiently, with rifaximin.

Discussion

Ammonia-reducing treatments should be considered in patients presenting with movement disorders due to chronic liver disease.

A double-blind randomized controlled trial to assess efficacy of bromocriptine in cirrhotic patients with hepatic parkinsonism

BACKGROUND

Parkinsonism like features can be seen in cirrhotics, possibly related to alterations in brain dopamine metabolism, transport and receptor integrity at basal ganglia. Hepatic parkinsonism is often not suspected and only ammonia-reducing therapies are given to such patients. We investigated the efficacy and safety of bromocriptine, a dopaminergic agent, in patients with hepatic parkinsonism.

PATIENTS AND METHODS

Cirrhotics were screened for the presence of extrapyramidal symptoms and were diagnosed as hepatic parkinsonism if any two of tremor, bradykinesia and/or rigidity were present, supported by MRI brain showing T1 hyperintensities in basal ganglia and substantia nigra. Patients were randomized to receive placebo (Gr A, n = 22) or bromocriptine (Gr B, n = 24) for 12 weeks. Complete, partial and non-response were defined as 30%, 10%-30% and <10% reduction,respectively, in Unified Parkinson's Disease Rating Scale motor score.

RESULTS

Of 1016 cirrhotics, 50 (4.9%) had hepatic parkinsonism. Patients in two treatment groups were comparable for MELD score, arterial NH3 and frequency of portosystemic shunts. Bromocriptine therapy for 12 weeks resulted in improvement in rigidity, tremors, bradykinesia and gait compared to placebo with complete and partial response in seven vs none (29.1%, 0%, P < 0.01) and 12 vs one (50%, 4.5%, P < 0.01) patients. Prolonged and more severe motor symptoms were associated with non-response to bromocriptine therapy. There were no major side effects in either treatment group.

CONCLUSIONS

Hepatic parkinsonism is seen in ~5% cirrhotics. Bromocriptine is a safe and effective therapy for these patients and is more effective in mild to moderate hepatic parkinsonism.

Hepatitis B and C virus infection as a risk factor for Parkinson's disease in Israel-A nationwide cohort study

OBJECTIVE

To study the association between hepatitis C and B viruses and Parkinson's disease (PD) in Israel.

METHODS

A retrospective cohort study was performed by analyzing the computerized database of Clalit Healthcare Service in Israel. Cohorts of people with hepatitis C virus (HCV) infection, hepatitis B virus (HBV) infection and nonalcoholic steatohepatitis (NASH) were constructed and compared to a reference cohort for prevalence of PD.

RESULTS

The prevalence of PD in Israel was found to be 0.5% in the general population. The M-H (Mantel-Haenszel) odds ratio (OR) of PD for HBV-positive patients was 1.08 (95% CI: 1.00-1.16). The M-H OR of PD for HCV-positive patients was 1.18 (95% CI: 1.04-1.35). The M-H OR of PD for patients infected with both hepatitis C and B was 1.13 (95% CI: 0.87-1.47). The M-H OR of PD for patients diagnosed with nonalcoholic steatohepatitis (NASH) was 1.13 (95% CI: 1.08-1.19).

CONCLUSIONS

We report evidence supporting a minor increased risk for PD in patients with HCV. Co infection of HCV and HBV was not associated with an increased risk for PD. The increased risk for PD in the group of patients with NASH, raises the possibility that liver disease per se is a risk factor for PD rather than viral infection. In addition, it cannot be ruled out that the association is, at least in part, the result of the occurrence of cirrhosis induced parkinsonism that was misclassified as PD.

Implications of Manganese in Chronic Acquired Hepatocerebral Degeneration

Neurological symptoms can be one of the over-riding symptoms in patients with liver cirrhosis. Patients can present with subtle changes in mood or neurological function due to hepatic encephalopathy (HE), to more severe presentations including stupor and coma. While HE, in its severe form, can be clinically easy to diagnose, more subtle forms may be more difficult to recognize. Other neurological diseases may indeed be overlooked in the context of cirrhosis or confuse the physician regarding the diagnosis. Chronic acquired hepatocerebral degeneration (CAHD) is an uncommon problem occurring in patients with cirrhosis characterised by a Parkinsonian-like neurological presentation with damage to the brain secondary to manganese (Mn) deposition. Here we describe a case of a patient with a neurological presentation of liver disease with a review of the current CAHD literature. In conclusion, CAHD is a rare condition occurring in liver cirrhosis that should always be considered in patients with neurological manifestations of chronic liver disease.

Acquired hepatocerebral degeneration (AHD): a peculiar neurological impairment in advanced chronic liver disease

We discuss the case of a rare and often unrecognized neurologic syndrome, called Acquired Hepatocerebral Degeneration (AHD), observed in patients with advanced liver disease and portosystemic shunts. The clinical manifestations can be very heterogeneous and in our case included a combination of cerebellar and extrapyramidal signs, arisen in a period of few days. Brain Magnetic Resonance Imaging (MRI) showed, in T1-weighted images, diffuse bilateral hyper intensities in basal ganglia and biemispheric brain and cerebellar cortices, resembling paramagnetic deposits. No other neurological impairments, like stroke, infection or neoplasia, were found. It was excluded an episode of acute hepatic encephalopathy. We also ruled out Wilsonian degeneration, iron overload and autoimmune encephalitis and we lastly found high manganese levels as the possible cause of the brain paramagnetic deposits. Even though either serum Mn determination or its accumulation in the brain are not specific for AHD, however the chronic and progressively worsening of the neurological manifestations advocated a degenerative condition, possibly AHD. We finally opted for the early restoration of liver function by OLT, and we observed complete clinical symptoms' resolution and partial MRI reversal after a follow up of 6 months.

Cerebellar ataxia and neuropathy as presenting features of hepatitis-B related cirrhosis and portal hypertension

Adult onset cerebellar dysfunction with neuropathy is a commonly encountered condition and is usually due to genetic causes such as spinocerebellar ataxia, gluten ataxia, alcohol related, toxic, degenerative, immune mediated, paraneoplastic causes and so on. Ataxia and neuropathy as presenting features of hepatitis-B related liver disease are very rare and have not been reported so far.

Recent Updates on Acquired Hepatocerebral Degeneration

BACKGROUND

Acquired hepatocerebral degeneration (AHD) refers to a chronic neurological syndrome in patients with advanced hepatobiliary diseases. This comprehensive review focuses on the pathomechanism and neuroimaging findings in AHD.

METHODS

A PubMed search was performed using the terms "acquired hepatocerebral degeneration," "chronic hepatocerebral degeneration," "Non-Wilsonian hepatocerebral degeneration," "cirrhosis-related parkinsonism," and "manganese and liver disease."

RESULTS

Multiple mechanisms involving the accumulation of toxic substances such as ammonia or manganese and neuroinflammation may lead to widespread neurodegeneration in AHD. Clinical characteristics include movement disorders, mainly parkinsonism and ataxia-plus syndrome, as well as cognitive impairment with psychiatric features. Neuroimaging studies of AHD with parkinsonism show hyperintensity in the bilateral globus pallidus on T1-weighted magnetic resonance images, whereas molecular imaging of the presynaptic dopaminergic system shows variable findings. Ataxia-plus syndrome in AHD may demonstrate high-signal lesions in the middle cerebellar peduncles on T2-weighted images.

DISCUSSION

Future studies are needed to elucidate the exact pathomechanism and neuroimaging findings of this heterogeneous syndrome.

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.

Hepatic encephalopathy coexists with acquired chronic hepatocerebral degeneration

Hyperkinetic extrapyramidal syndrome is the typical clinical characteristic of acquired hepatocerebral degeneration (AHD), but is usually not observed with hepatic encephalopathy (HE). We present a case of AHD coexisting with HE. Both conditions were secondary to liver cirrhosis and hepatitis C virus infection. The brain MRI showed bilateral and symmetric high T1 signal-intensity in the globus pallidus, and diffuse high signal-intensity of the hemispheric white matter on T2-FLAIR images. As we usually neglect the existence of AHD, the diagnosis is often ignored, especially when it coexists with HE. This case highlights the need to distinguish irreversible AHD from HE.

A lady with NASH and choreoathetosis

We describe a case of acquired hepatocerebral degeneration (AHD) presenting with confusion and worsening memory problems since her discharge from the gastroenterology units. Cases of AHD are rare and are frequently confused with hepatic encephalopathy and Wilson's disease. There are no proven pharmacological therapies for AHD. Information regarding the effect of orthotopic liver transplant on AHD is limited and conflicting. Most patients eventually die from the systemic complications of cirrhotic liver failure including infection, hepatic coma and hepatocellular carcinoma.

Neurologic manifestations of gastrointestinal and liver diseases

Hepatic and gastrointestinal disorders can produce a wide spectrum of neurologic complications both affecting the central nervous system (CNS) and the peripheral nervous system. These manifestations range in severity from coma in acute liver failure and acute pancreatitis, to minor cognitive changes in chronic portosystemic encephalopathy and hepatitis C. Cerebrovascular diseases can complicate hepatitis C infection and inflammatory bowel disease. Demyelinating disorders may co-exist with inflammatory bowel disease. Anti-tumor necrosis factor alpha drugs may induce demyelination. Ataxia may occur in malabsorption syndromes and in gluten related disorders. Characteristic movement disorders are key features of acquired hepatocerebral degeneration and of Whipple disease. Multiple types of neuropathy can be found in association with hepatitis, inflammatory bowel disease and gluten related disorders.

Neurologic Manifestations of Chronic Liver Disease and Liver Cirrhosis

The normal functioning of brain is intimately as well as intricately interrelated with normal functioning of the liver. Liver plays a critical role of not only providing vital nutrients to the brain but also of detoxifying the splanchnic blood. Compromised liver function leads to insufficient detoxification thus allowing neurotoxins (such as ammonia, manganese, and other chemicals) to enter the cerebral circulation. In addition, portosystemic shunts, which are common accompaniments of advanced liver disease, facilitate free passage of neurotoxins into the cerebral circulation. The problem is compounded further by additional variables such as gastrointestinal tract bleeding, malnutrition, and concurrent renal failure, which are often associated with liver cirrhosis. Neurologic damage in chronic liver disease and liver cirrhosis seems to be multifactorial primarily attributable to the following: brain accumulation of ammonia, manganese, and lactate; altered permeability of the blood-brain barrier; recruitment of monocytes after microglial activation; and neuroinflammation, that is, direct effects of circulating systemic proinflammatory cytokines such as tumor necrosis factor, IL-1β, and IL-6. Radiologist should be aware of the conundrum of neurologic complications that can be encountered in liver disease, which include hepatic encephalopathy, hepatocerebral degeneration, hepatic myelopathy, cirrhosis-related parkinsonism, cerebral infections, hemorrhage, and osmotic demyelination. In addition, neurologic complications can be exclusive to certain disorders, for example, Wilson disease, alcoholism (Wernicke encephalopathy, alcoholic cerebellar degeneration, Marchiafava-Bignami disease, etc). Radiologist should be aware of their varied clinical presentation and radiological appearances as the diagnosis is not always straightforward.

Challenges in diagnosing hepatic encephalopathy

The term "hepatic encephalopathy" (HE) covers the neuropsychiatric syndrome associated with acute, chronic and acute-on-chronic liver disease (CLD). This paper deals with clinical features and diagnosis of HE in patients with liver cirrhosis and portal hypertension or porto-systemic shunts. The possible impact of concomitant disorders and the cirrhosis underlying liver disease upon brain function is described emphasizing the need of a detailed diagnostic work up of every individual case before diagnosing HE. Currently used methods for diagnosing minimal or covert hepatic encephalopathy are compared with regard to their sensitivity and specificity for diagnosing HE against the background of a multitude of concomitant disorders and diseases that could contribute to brain dysfunction.

Acute stroke-like presentation of acquired hepatocerebral degeneration

Neurological manifestations in liver diseases have been well-described. Parkinsonism developing in cirrhotic patients is a unique clinical, neuroradiological, and biological entity. The symptoms are often insidious in onset and occur after liver disease has made its presentation. Acute dysarthria as the presenting manifestation of cirrhosis is rare. Here we report three cases where liver disease made an unusual presentation as acute dysarthria. In all cases the abruptness of the onset prompted the treating physicians to make a diagnosis of stroke. The computed tomography (CT) scans of all these patients did not show any evidence of stroke. This was followed by magnetic resonance imaging (MRI) which showed the characteristic symmetric high-signal intensities in globus pallidus and substantia nigra in T1-weighted images, a reflection of increased tissue concentrations of manganese that helped in making a retrospective diagnosis of liver disease, confirmed later by altered serum albumin to globulin ratios and altered liver echo texture in ultra sonogram.

Pallidal index as biomarker of manganese brain accumulation and associated with manganese levels in blood: a meta-analysis

OBJECTIVE

The current study was designed to evaluate the sensitivity, feasibility, and effectiveness of the pallidal index (PI) serving as a biomarker of brain manganese (Mn) accumulation, which would be used as an early diagnosis criteria for Mn neurotoxicity.

METHODS

The weighted mean difference (WMD) of the PI between control and Mn-exposed groups was estimated by using a random-effects or fixed-effects meta-analysis with 95% confidence interval (CI) performed by STATA software version 12.1. Moreover, the R package "metacor" was used to estimate correlation coefficients between PI and blood Mn (MnB).

RESULTS

A total of eight studies with 281 occupationally Mn-exposed workers met the inclusion criteria. Results were pooled and performed with the Meta-analysis. Our data indicated that the PI of the exposed group was significantly higher than that of the control (WMD: 7.76; 95% CI: 4.86, 10.65; I2 = 85.7%, p<0.0001). A random effects model was used to perform meta-analysis. These findings were remarkably robust in the sensitivity analysis, and publication bias was shown in the included studies. Seven out of the eight studies reported the Pearson correlation (r) values. Significantly positive correlation between PI and MnB was observed (r = 0.42; 95% CI, 0.31, 0.52).

CONCLUSIONS

PI can be considered as a sensitive, feasible, effective and semi-quantitative index in evaluating brain Mn accumulation. MnB can also augment the evaluation of brain Mn accumulation levels in the near future. However, the results should be interpreted with caution.

Parkinsonian syndrome and ataxia as a presenting finding of acquired hepatocerebral degeneration

The term "acquired hepatocerebral degeneration" (AHD) was coined to describe clinical entity distinct from genetically defined Wilson's disease. AHD is chronic neurological disorder, characterized by extrapyramidal and neuropsychiatric symptoms accompanied with advanced liver disease with portosystemic shunts. In majority of AHD cases, extrapyramidal symptoms appear in the presence of known liver disease. Here we present a patient with subacute onset of bilateral, asymmetric, hypokinetic-rigid syndrome and ataxia as initial presentation of liver cirrhosis. Manganese toxicity have major role in AHD pathogenesis. Failure of liver detoxification and presence of portosystemic shunting enables neurotoxic substance of manganese to avoid hepatic metabolism and to enter and accumulate in central nervous system. Predilection brain regions for manganese deposits are globus pallidum (GP) and substantia nigra (SN). Characteristic MRI findings of bilateral, symmetrical hyperintensities of GP and SN on T1-weighted sequences supported the diagnosis of AHD in our patient. In addition, increased T2 signal in dendate nuclei seen in our patient is rare radiological finding. So far, no consensus guidelines regarding medical treatment of AHD exist. We initiated low-dose levodopa treatment, but failed to provide beneficial effect. In conclusion, AHD is distinct clinical entity that should be included in differential diagnosis of both typical and atypical parkinsonian syndromes. Furthermore, our case highlights the importance of performing MRI in patients with atypical parkinsonism.

Parkinsonism in cirrhosis: pathogenesis and current therapeutic options

Acquired hepatolenticular degeneration, also known as "Parkinsonism in cirrhosis" is characterized by extrapyramidal symptoms including hypokinesia, dystonia and rigidity that are rapidly progressive and may be independent of the severity of cognitive dysfunction. Magnetic resonance imaging reveals T1-weighted hyperintense signals in both globus pallidus and substantia nigra. Estimates of the prevalence of Parkinsonism in cirrhosis have been reported as high as 21 %. The cause of Parkinsonism in cirrhosis has been attributed to manganese deposition in basal ganglia structures, leading to the dysfunction of the dopaminergic neurotransmitter system. In particular, there is evidence from both spectroscopic and biochemical investigations for damage to (or dysfunction of) presynaptic dopamine transporters together with a loss of post-synaptic dopamine receptors in basal ganglia of affected patients. Therapeutic options are limited; ammonia-lowering strategies are without substantial benefit, and an effective manganese chelator is not available. In many patients, L-Dopa replacement therapy and the dopamine receptor agonist bromocriptine are beneficial, and liver transplantation is generally effective. However, reports of post-transplant residual extrapyramidal symptoms suggest an element of irreversibility in some cases.

Cirrhosis-related Parkinsonism: prevalence, mechanisms and response to treatments

BACKGROUND & AIMS

Extrapyramidal and cerebellar symptoms belong to the most prominent features of episodic hepatic encephalopathy, and usually decrease upon ammonia-lowering therapy. Rapidly progressing parkinsonian symptoms, which are unresponsive to treatment of hepatic encephalopathy, indicate cirrhosis-related Parkinsonism. This study aims at analyzing the prevalence of cirrhosis-related Parkinsonism in patients with liver cirrhosis, and to study the functional status of the striatal dopaminergic system in these patients.

METHODS

214 patients with liver cirrhosis who were consecutively seen at the out-patient clinic for liver transplant candidates and/or at the transplantation wards at Hannover Medical School, between August 1, 2008 and March 31, 2011, underwent a standardized neurological examination while on the waiting list or immediately after liver transplantation. Single photon emission computer tomography (SPECT) using (123)I-beta-CIT, for the evaluation of the striatal dopamine transporter function, and (123)I-IBZM for the evaluation of the striatal dopamine D2 receptor availability, was performed in 6 patients with cirrhosis-related Parkinsonism.

RESULTS

Cirrhosis-related Parkinsonism was diagnosed in 9 of 214 patients (4.2%). SPECT revealed significantly decreased dopamine receptor availability in 5 of 6 patients studied, and significantly decreased dopamine transporter availability in 3. Levodopa improved motor dysfunction in two of four patients treated, although only temporarily. Incomplete recovery was observed in two patients after liver transplantation.

CONCLUSIONS

Cirrhosis-related Parkinsonism is more frequent than presumed. The presented data suggest pre- and postsynaptic alteration of striatal dopaminergic neurotransmission as a possible cause of cirrhosis-related Parkinsonism and reveal the limited effects of dopaminergic therapy.

Manganese and the brain

Manganese (Mn) is an essential trace metal that is pivotal for normal cell function and metabolism. Its homeostasis is tightly regulated; however, the mechanisms of Mn homeostasis are poorly characterized. While a number of proteins such as the divalent metal transporter 1, the transferrin/transferrin receptor complex, the ZIP family metal transporters ZIP-8 and ZIP-14, the secretory pathway calcium ATPases SPCA1 and SPCA2, ATP13A2, and ferroportin have been suggested to play a role in Mn transport, the degree that each of them contributes to Mn homeostasis has still to be determined. The recent discovery of SLC30A10 as a crucial Mn transporter in humans has shed further light on our understanding of Mn transport across the cell. Although essential, Mn is toxic at high concentrations. Mn neurotoxicity has been attributed to impaired dopaminergic (DAergic), glutamatergic and GABAergic transmission, mitochondrial dysfunction, oxidative stress, and neuroinflammation. As a result of preferential accumulation of Mn in the DAergic cells of the basal ganglia, particularly the globus pallidus, Mn toxicity causes extrapyramidal motor dysfunction. Firstly described as "manganism" in miners during the nineteenth century, this movement disorder resembles Parkinson's disease characterized by hypokinesia and postural instability. To date, a variety of acquired causes of brain Mn accumulation can be distinguished from an autosomal recessively inherited disorder of Mn metabolism caused by mutations in the SLC30A10 gene. Both, acquired and inherited hypermanganesemia, lead to Mn deposition in the basal ganglia associated with pathognomonic magnetic resonance imaging appearances of hyperintense basal ganglia on T1-weighted images. Current treatment strategies for Mn toxicity combine chelation therapy to reduce the body Mn load and iron (Fe) supplementation to reduce Mn binding to proteins that interact with both Mn and Fe. This chapter summarizes our current understanding of Mn homeostasis and the mechanisms of Mn toxicity and highlights the clinical disorders associated with Mn neurotoxicity.

Dystonia with brain manganese accumulation resulting from SLC30A10 mutations: a new treatable disorder

Background

The first gene causing early-onset generalized dystonia with brain manganese accumulation has recently been identified. Mutations in the SLC30A10 gene, encoding a manganese transporter, cause a syndrome of hepatic cirrhosis, dystonia, polycythemia, and hypermanganesemia.

Methods

We present 10-year longitudinal clinical features, MRI data, and treatment response to chelation therapy of the originally described patient with a proven homozygous mutation in SLC30A10.

Results

The patient presented with early-onset generalized dystonia and mild hyperbilirubinemia accompanied by elevated whole-blood manganese levels. T1-sequences in MRI showed hyperintensities in the basal ganglia and cerebellum, characteristic of manganese deposition. Treatment with intravenous disodium calcium edetate led to clinical improvement and reduction of hyperintensities in brain imaging.

Conclusions

We wish to highlight this rare disorder, which, together with Wilson's disease, is the only potentially treatable inherited metal storage disorder to date, that otherwise can be fatal as a result of complications of cirrhosis. © 2012 Movement Disorder Society

Basal ganglia intensity indices and diffusion weighted imaging in manganese-exposed welders

OBJECTIVES

Manganese exposure leads to diffuse cerebral metal deposition with the highest concentration in the globus pallidus associated with increased T1-weighted MRI signal. T1 signal intensity in extra-pallidal basal ganglia (caudate and putamen) has not been studied in occupationally exposed workers. Diffusion weighted imaging is a non-invasive measure of neuronal damage and may provide a quantification of neurotoxicity associated with welding and manganese exposure. This study investigated extra-pallidal T1 basal ganglia signal intensity as a marker of manganese exposure and basal ganglia diffusion weighted imaging abnormalities as a potential marker of neurotoxicity.

METHODS

A 3T MR case:control imaging study was performed on 18 welders and 18 age- and gender-matched controls. Basal ganglia regions of interest were identified for each subject. T1-weighted intensity indices and apparent diffusion coefficients were generated for each region.

RESULTS

All regional indices were higher in welders than controls (p ≤ 0.05). Combined basal ganglia (ρ = 0.610), caudate (ρ = 0.645), anterior (ρ = 0.595) and posterior putamen (ρ = 0.511) indices were more correlated with exposure than pallidal (ρ = 0.484) index. Welder apparent diffusion coefficient values were lower than controls for globus pallidus (p = 0.03) and anterior putamen (p = 0.004).

CONCLUSIONS

Welders demonstrated elevated T1 indices throughout the basal ganglia. Combined basal ganglia, caudate and putamen indices were more correlated with exposure than pallidal index suggesting more inclusive basal ganglia sampling results in better exposure markers. Elevated indices were associated with diffusion weighted abnormalities in the pallidum and anterior putamen suggesting neurotoxicity in these regions.

Syndrome of hepatic cirrhosis, dystonia, polycythemia, and hypermanganesemia caused by mutations in SLC30A10, a manganese transporter in man

Environmental manganese (Mn) toxicity causes an extrapyramidal, parkinsonian-type movement disorder with characteristic magnetic resonance images of Mn accumulation in the basal ganglia. We have recently reported a suspected autosomal recessively inherited syndrome of hepatic cirrhosis, dystonia, polycythemia, and hypermanganesemia in cases without environmental Mn exposure. Whole-genome mapping of two consanguineous families identified SLC30A10 as the affected gene in this inherited type of hypermanganesemia. This gene was subsequently sequenced in eight families, and homozygous sequence changes were identified in all affected individuals. The function of the wild-type protein and the effect of sequence changes were studied in the manganese-sensitive yeast strain Δpmr1. Expressing human wild-type SLC30A10 in the Δpmr1 yeast strain rescued growth in high Mn conditions, confirming its role in Mn transport. The presence of missense (c.266T>C [p.Leu89Pro]) and nonsense (c.585del [p.Thr196Profs(∗)17]) mutations in SLC30A10 failed to restore Mn resistance. Previously, SLC30A10 had been presumed to be a zinc transporter. However, this work has confirmed that SLC30A10 functions as a Mn transporter in humans that, when defective, causes Mn accumulation in liver and brain. This is an important step toward understanding Mn transport and its role in neurodegenerative processes.

Extent of reversibility of hepatic encephalopathy following liver transplantation

Although hepatic encephalopathy (HE) is prevalent in the cirrhotic population, it has also been considered a potentially reversible condition. Liver transplantation represents the ultimate reversal of the decompensated cirrhotic state and should provide the best option for the reversibility of HE. However, the neurologic compromise associated with HE in the cirrhotic patient may not be completely reversible. Theories regarding fixed structural and reversible metabolic deficits as well as persistence of the hyperdynamic state with continued portosystemic shunting have been proposed to explain this lack of complete reversibility. Whether this remnant neurologic deficit is clinically significant remains unclear.

[Case of acquired hepatocerebral degeneration with prominent improvement of parkinsonism and cognitive deficits after living-donor liver transplantation]

A 53-year-old woman visited us for a neurological consultation before her liver transplantation. She had a history of primary biliary cirrhosis that began at 37 years of age. She showed falling episodes and met with a traffic accident at 52 years old. Since then, her symptoms had worsened. The neurological examination showed masked face, rigidity on bilateral arms and legs, and lack of balance. Her Mini-Mental State Examination Score was 28/30, but she suffered from loss of memory and had trouble with executive function in detailed examinations. Her T(1) weighted image showed hyperintensity in bilateral globus pallidus, putamen, dentate nucleus and cerebral peduncle. There was a significant improvement in intellectual function and neurological signs 6 months after her orthotopic liver transplantation. In addition, post-liver transplantation images showed a decrease in the area of hyperintensities. This case suggests that even in a patient with severe liver cirrhosis a complete cure of neurological manifestations can be obtained after the liver transplantation.

Acquired hepatocerebral degeneration: A case report

Acquired hepatocerebral degeneration is an underdiagnosed neurologic syndrome characterized by parkinsonism, ataxia or other movement disorders and by neuropsychiatric and cognitive symptoms. It occurs in patients with chronic liver disease, especially those who develop portosystemic shunting and is often unrecognized as a cause of cognitive decline. Recently, its pathogenesis has been associated with manganese accumulation in basal ganglia and some treatments proposed. The aim of this article was to report a case and discuss some discoveries in connection with the disease.