Hepatic myelopathy: an unusual neurological complication of advanced hepatic disease

Metabolic and Toxic Myelopathies

Metabolic and toxic causes of myelopathy form a heterogeneous group of disorders. In this review, we discuss the causes of metabolic and toxic myelopathies with respect to clinical presentation, pathophysiology, diagnostic testing, treatment, and prognosis. This review is organized by temporal course (hyperacute, acute, subacute, and chronic) and etiology (e.g., nutritional deficiency, toxic exposure). Broadly, the myelopathies associated with dietary toxins (neurolathyrism, konzo) and decompression sickness present suddenly (hyperacute). The myelopathies associated with heroin use and electrical injury present over hours to days (acutely). Most nutritional deficiencies (cobalamin, folate, copper) and toxic substances (nitrous oxide, zinc, organophosphates, clioquinol) cause a myelopathy of subacute onset. Vitamin E deficiency and hepatic myelopathy cause a chronic myelopathy. Radiation- and intrathecal chemotherapy-induced myelopathy can cause a transient and/or a progressive syndrome. For many metabolic and toxic causes of myelopathy, clinical deficits may stabilize or improve with rapid identification and treatment. Familiarity with these disorders is therefore essential.

Spastic paraparesis associated with advanced liver cirrhosis: a condition obscure in terms of treatment and prognosis

Hepatic myelopathy or spastic paraparesis of liver disease is an insidious onset condition with pure motor spastic paraparesis without sensory, bladder or bowel involvement in patients with chronic liver disease, in which the neurological dysfunction cannot be explained by other causes. It is a rare, relentlessly progressive and mostly irreversible neurological complication resulting from portosystemic shunts occurring spontaneously, created surgically or due to 'functional shunting'. In some cases, no evidence of shunting is elicitable due to difficulty in locating the hidden collaterals. We report this rare case of a 33-year-old man with chronic liver disease presenting with spastic paraparesis after 11 months of resolution of an episode of hepatic encephalopathy.

State of the art of management of hepatic myelopathy

Hepatic myelopathy (HM) is characterized by progressive weakness and spasticity of the lower extremities, which is a severe spinal cord involvement rarely occurring in patients with cirrhosis or other chronic liver diseases. The diagnosis is assigned after the exclusion of other clinical entities leading to spastic paraparesis. Liver transplantation represents a potentially treatment for HM in early stage.

HCV-related central and peripheral nervous system demyelinating disorders

Chronic infection with hepatitis C virus (HCV) is associated with a large spectrum of extrahepatic manifestations (EHMs), mostly immunologic/rheumatologic in nature owing to B-cell proliferation and clonal expansion. Neurological complications are thought to be immune-mediated or secondary to invasion of neural tissues by HCV, as postulated in transverse myelitis and encephalopathic forms. Primarily axonal neuropathies, including sensorimotor polyneuropathy, large or small fiber sensory neuropathy, motor polyneuropathy, mononeuritis, mononeuritis multiplex, or overlapping syndrome, represent the most common neurological complications of chronic HCV infection. In addition, a number of peripheral demyelinating disorders are encountered, such as chronic inflammatory demyelinating polyneuropathy, the Lewis-Sumner syndrome, and cryoglobulin-associated polyneuropathy with demyelinating features. The spectrum of demyelinating forms also includes rare cases of iatrogenic central and peripheral nervous system disorders, occurring during treatment with pegylated interferon. Herein, we review HCV-related demyelinating conditions, and disclose the novel observation on the significantly increased frequency of chronic demyelinating neuropathy with anti-myelin-associated glycoprotein antibodies in a cohort of 59 consecutive patients recruited at our institution. We also report a second case of neuromyelitis optica with serum IgG autoantibody against the water channel aquaporin-4. The prompt recognition of these atypical and underestimated complications of HCV infection is of crucial importance in deciding which treatment option a patient should be offered.

Clinical neurophysiology of hepatic encephalopathy

BACKGROUND/OBJECTIVES

Hepatic encephalopathy (HE) has relevant impact on the quality of life of patients and their caregivers and causes relevant costs because of hospitalizations and work days lost. Its quantification is important to perform adequate clinical trials on this relevant complication of cirrhosis and portal-systemic shunting. Clinical neurophysiology, which detects functional alterations of the nervous system, has been applied to the study of HE for over 60 years. This review aims at summarizing and clarifying the role of neurophysiologic techniques in the study of HE.

METHODS

A narrative review was performed aiming at interpreting the cited papers and the techniques on the basis of their physiological and pathophysiological meaning.

RESULTS

The potential role of EEG, quantified EEG, evoked potentials-both exogenous, endogenous and motor-have been clarified to the reader that may be unfamiliar with neurophysiology.

CONCLUSIONS

The EEG, reflecting the oscillatory changes of neural network is the preferable tool to detect and monitor HE, with the exception of its most severe stage, when EEG flattens. SSEP and MEP have indication to detect and monitor transmission alterations that are likely related to myelin changes and microedema.

[Reversible hepatic myelopathy: a case report]

We report a case of reversible hepatic myelopathy. A 42-year-old female patient with 3-year history of alcoholic liver cirrhosis developed spastic gait, hyperreflexia and mild somatosensory disturbance in her lower extremities. The increased level of serum ammonia and the deficits of N30 and P38 in the tibial somatosensory evoked potentials (SEP) in conjunction with exclusion of the other known causes of myelopathy supported the diagnosis of her hepatic myelopathy. The ammonia lowering therapy by the oral administration of lactulose successfully improved the spastic gait accompanied with the emergence of N30 and P38 in the tibial SEP. Although liver transplantation was known to be the only therapy for hepatic myelopathy in the literatures, our case showed that the ammonia lowering therapy can be effective for the early stage of hepatic myelopathy.

Spinal cord involvement in patients with cirrhosis

A severe spinal cord involvement may rarely occur in patients with cirrhosis and other chronic liver diseases; this complication is usually associated with overt liver failure and surgical or spontaneous porto-systemic shunt. Hepatic myelopathy (HM) is characterized by progressive weakness and spasticity of the lower extremities, while sensory and sphincter disturbances have rarely been described and are usually less important. The diagnosis is assigned in the appropriate clinical setting on clinical grounds after the exclusion of other clinical entities leading to spastic paraparesis. Magnetic resonance imaging is often unremarkable; however, also intracerebral corticospinal tract abnormalities have been reported recently. The study of motor evoked potentials may disclose central conduction abnormalities even before HM is clinically manifest. HM responds poorly to blood ammonia-lowering and other conservative medical therapy. Liver transplantation represents a potentially definitive treatment for HM in patients with decompensated cirrhosis of Child-Pugh B and C grades. Other surgical treatment options in HM include surgical ligation, shunt reduction, or occlusion by interventional procedures.

Immune-mediated myelitis associated with hepatitis virus infections

Virus-induced spinal cord damage results from a cytolytic effect on anterior horn cells or from predominantly cellular immune-mediated damage of long white matter tracts. Infection with the hepatitis virus group, most notably hepatitis C virus, has infrequently been associated with the occurrence of myelitis. The pathogenesis of hepatitis virus-associated myelitis has not been clarified: virus-induced autoimmunity (humoral or cell-mediated, possibly vasculitic) seems the most likely disease mechanism. Limited available information offers no evidence of direct hepatitis virus infection of the spinal cord. Virus neuropenetration may occur after virus-infected mononuclear cells penetrate the blood-brain barrier, but a true neurolytic effect has not been demonstrated. Attacks of acute myelitis usually respond favorably to immunomodulatory therapy. Antiviral therapy plays no confirmed role in the treatment of acute bouts of myelitis, but may limit the relapsing course of HCV-associated myelitis.

Use of model for end-stage liver disease exception points for early liver transplantation and successful reversal of hepatic myelopathy with a review of the literature

Hepatic myelopathy (HM) is a rarely reported disorder characterized by progressive spastic paraparesis due to impaired corticospinal tract function in the setting of cirrhosis or portosystemic shunting. HM has not to date been recognized as a Model for End-Stage Liver Disease (MELD) exception for transplantation. Outcomes for a small number of patients from Europe and Asia who have undergone liver transplantation (LT) for HM suggest a potential neurological benefit, especially with earlier transplantation. We report the first use of MELD exception points for the condition of HM to enable early LT resulting in the reversal of marked spastic paraparesis. Our patient, whose myelopathy had markedly progressed without further hepatic decompensation, underwent LT 14 months after the diagnosis of HM with an adjusted MELD score of 30, which was granted as a United Network for Organ Sharing exception. After LT, there was significant neurological improvement as the patient progressed from wheelchair dependency to full ambulation. We reviewed the literature of other HM patients who had undergone LT. With our patient, there were in all 15 reported cases of LT in individuals with HM. LT can lead to a marked improvement in HM, particularly in the earlier clinical stages of the disorder. Early LT can be accomplished, as in our case, by the submission of an appeal for a MELD upgrade.

Hepatic myelopathy as a presenting neurological complication in patients with cirrhosis and spontaneous splenorenal shunt

Hepatic myelopathy is a rare complication of chronic liver disease that is associated with extensive portosystemic shunts. The main clinical feature of hepatic myelopathy is progressive spastic paraparesis in the absence of sensory or sphincter impairment. Early and accurate diagnosis of hepatic myelopathy is important because patients with early stages of the disease can fully recover following liver transplantation. Motor-evoked potential studies may be suitable for the early diagnosis of hepatic myelopathy, even in patients with preclinical stages of the disease. Here we describe two patients who presented with spastic paraparesis associated with a spontaneous splenorenal shunt and without any previous episode of hepatic encephalopathy. One patient experienced improved neurologic symptoms after liver transplantation, whereas the other patient only received medical treatment, which did not prevent the progression of spastic paraparesis.

Fulminant central nervous system demyelination associated with interferon-α therapy and hepatitis C virus infection

Hepatitis C virus (HCV) infection is common in the general population and may coincide with disease in the central and peripheral nervous system. Interferon-α (IFN-α) is used as treatment for HCV infection. The therapeutic benefit is assumed to result from activation of natural killer cells and CD8+ T cells. Despite its beneficial effects, it has been associated with a number of autoimmune disorders, such as chronic inflammatory demyelinating polyneuropathy and multiple sclerosis. Several clinical reports including magnetic resonance imaging exist, but neuropathological confirmation of MS associated with IFN-α therapy and HCV infection is lacking. We report a case of a female patient with chronic HCV infection who developed `acute MS'-like demyelinating disease after IFN-α administration, with extensive lesions throughout brain and thoracic spinal cord. The patient died after a disease duration of 6 months. Brain autopsy revealed Baló-like demyelinating plaques with positive HCV sequences within florid lesions. The development of fulminant demyelinating disease after administration of IFN-α suggests that autoimmune mechanisms such as T cell mediated tissue damage might be initiated or aggravated by IFN-α therapy. Additionally, the presence of HCV RNA within the demyelinated lesion indicates a possible role in triggering or propagating disease. Multiple Sclerosis 2007; 13: 1100—1106. http://msj.sagepub.com

A case report of progressive multifocal leukoencephalopathy in a human T-cell lymphotropic virus type 1-infected hemodialytic patient

We experienced a case manifesting progressive multifocal leukoencephalopathy (PML) in a hemodialytic patient with hepatitis C virus-induced liver cirrhosis and human T-cell lymphotropic virus type-1 (HTLV-1)-associated uveitis. A 57-year-old male patient had received chronic hemodialysis therapy for 10 years, during which he received multiple blood transfusions and HTLV-1-associated uveitis developed. He complained of visual disturbance and disorientation. Brain CT scan showed diffuse and multifocal low density areas in occipital and temporal lobes, with gray matter relatively spared. MRI imaging showed high intensity lesions in the same areas. Cerebrospinal fluid culture was negative, but using nested PCR, rearranged regulatory region of JC virus DNA was detected. His consciousness level gradually deteriorated and complete paraplegia developed. Seven months after admission, he died of pneumonia. An autopsy confirmed the diagnosis of PML. Notably, mononuclear cell infiltration, gliosis and demyelinating lesions but no nuclear inclusion bodies were observed in the thoracic cord, which suggested HTLV-1-associated myelopathy. Because JC virus is activated under immunocompromised conditions, precipitating factors in this case appear multifactorial; depressed immune system induced by chronic hemodialysis as well as blood-borne hepatitis C virus/HTLV-1 infection might contribute to the activation of dormant JC virus and the development of florid clinical manifestation of PML.

Portosystemic myelopathy: spastic paraparesis after portosystemic shunting

Portosystemic encephalopathy (PSE) is a well-known, common complication of portal hypertension. It is thought to be caused by nitrogenous substances such as ammonia, which are normally cleared from the blood stream by the liver. In cirrhosis and other hepatic disorders with portosystemic shunting (PSS)-- either surgical portosystemic anastomoses (PSA) or spontaneous PSS-- the collateral vessels bypass the liver allowing the accumulation of toxic, ammoniacal substances in the blood and tissues. PSE is characterized by encephalopathy; portosystemic myelopathy (PSM) is characterized by paresis of the extremities, Babinski signs and muscle spasticity in patients with cirrhosis and/or PSS. Usually only the lower extremities are involved. This report presents the first case of this syndrome observed 5 years after a transjugular intrahepatic portosystemic shunt. The 31 year old man with chronic Hepatitis B developed complete spastic paraparesis within 4 weeks after onset of clinical/neurological symptoms, accompanied by an episode of severe hepatic encephalopathy. The transcortical magnetic stimulation showed normal motoric stimulation times to the abductor digiti minimi muscles but no stimulation to the tibialis muscles was seen. Lumbar stimulation to the tibialis muscles, however, was normal. This indicates loss of motor neurons in the spinal cord, a characteristic finding in patients with portosystemic myelopathy. We performed a search of the literature for all reported cases of cirrhosis and/or PSS that developed PSM. However, the intervals between the construction of a shunt and the diagnosis of portosystemic myelopathy were shorter in total portacaval shunts (median 16 months) than in partial, non-portacaval shunts (median 60 months, p < 0.01). This suggests that not only the shunt itself but also the shunted volume contributes to the development of the syndrome Sixty-one patients with PSM have been reported in the literature since 1944. PSE had developed before PSM in almost all cases. PSM occurred from 1 month to 10 years after the creation of portacaval anastomoses (PCA) or splenorenal shunts (SRS) or in cirrhotic patients without shunts. No one type of liver disease or type of shunt appears to predispose to PSM. The mechanisms of PSE and PSM are thought to be similar and of nitrogenous origin, but their pathogenesis remains unknown. Lathyrism, a toxic syndrome with similar symptoms and signs, is caused by the ingestion of a legume, Lathyrus sativa, which contains beta-N-oxalo-L amino-L-alanine (BOAA). This animal model with or without BOAA appears to offer a reliable way of studying PSM experimentally.

Recurrent demyelinating myelitis associated with hepatitis C viral infection

We report a 46-year-old-man who developed recurrent myelitis associated with hepatitis C viral (HCV) infection. Spinal cord biopsy showed acute demyelination without evidence of vasculitis. Antibodies to HCV were present in the CSF; HCV RNA was not detected in the CSF. Neither HCV antigens nor RNA were detected in the spinal cord biopsy, whereas they were found in the liver biopsy. Evaluation for other infectious or autoimmune causes was unrevealing. These observations suggest that recurrent myelitis in this patient is etiologically related to HCV infection, possibly via an immune-mediated mechanism. This is the first report of pathologically proven myelitis associated with HCV infection and we suggest that HCV be considered in the differential diagnosis of the transverse myelitis syndrome.

Paraparesis, hypermanganesaemia, and polycythaemia: a novel presentation of cirrhosis

Progressive myelopathy is a rare complication of chronic hepatic disease which has never been reported in the paediatric age group. We describe the 11 year course of an adolescent male with hepatic myelopathy caused by cryptogenic micronodular cirrhosis. His condition has been associated with persistent polycythaemia and extraordinary increases of whole blood manganese, with magnetic resonance imaging evidence of manganese deposition within the basal ganglia and other regions of the brain. The patient has developed neither liver failure nor parkinsonism. The pathophysiological bases of this multiorgan system disorder are described.

Hepatic myelopathy. Case report with review of the literature

Hepatic myelopathy is a rare complication of hepatic insufficiency, causing progressive spastic paraparesis. There are few reports detailing the clinical and diagnostic aspects of this uncommon cause of neurological deterioration in patients with liver disease. Early recognition of this disorder will become more important as patients with liver disease survive longer due to medical advances, including liver transplantation. We present an additional patient with hepatic myelopathy associated with infantile portal vein thrombosis and review the previous reports of hepatic myelopathy in the English literature.