Demyelinating neuropathy in patients with hepatitis C virus infection

Hepatitis C Virus-Related Central and Peripheral Nervous System Disorders

Hepatitis C Virus (HCV), despite being a hepatotropic virus, is the causative agent of many systemic disorders, such as vasculitis, autoimmune diseases, lymphoproliferative disorders, and a broad spectrum of neurological and psychiatric manifestations. Although symptoms have been misdiagnosed or underdiagnosed, only recently, evidence of direct (inflammatory) or indirect (immune-mediated) HCV-dependent cerebral effects has been established. HCV infection can promote acute inflammatory response, pro-coagulative status and ischemic disorders, and neurodegeneration. These effects rely on cerebral HCV replication, possibly mediated by blood-brain barrier alterations. Further study is needed to better understand the HCV-related mechanisms of brain damage.

[Neurological complications of hepatitis C infections]

Die chronische Hepatitis-C-Virus(HCV)-Infektion ist eine hochprävalente Systemerkrankung, die verschiedene neurologische Komplikationen verursachen kann. Es lassen sich HCV-assoziierte Symptome im zentralen und peripheren Nervensystem sowie der Muskulatur unterscheiden. Wichtige Pathomechanismen sind die HCV-assoziierte Autoimmunität (z. B. gemischte Kryoglobulinämie mit Polyneuropathie) und direkte Neurotoxizität (z. B. bei HCV-assoziierten kognitiven Defiziten). Die häufigsten neurologischen Komplikationen sind distal-symmetrische Polyneuropathien, Small-fiber-Neuropathien und kognitive Defizite. Die HCV-Infektion stellt außerdem einen Risikofaktor für ischämische und hämorrhagische Schlaganfälle sowie den Morbus Parkinson dar. Die frühe Identifikation und antivirale Behandlung HCV-positiver Patienten steht im Zentrum der Behandlung. Durch neue antivirale Therapien können >90 % der Patienten dauerhaft von der HCV-Infektion geheilt werden.

Hepatitis C-related cryoglobulinemic neuropathy: potential role of oxcarbazepine for pain control

BACKGROUND

Peripheral neuropathy is one most common, limiting and invalidating neurological symptom in subjects with hepatitis C virus and mixed cryoglobulinemia. Notably, the medical therapy proposed to eradicate HCV, can frequently exacerbate the painful neuropathy. Therefore, neuropathy therapies are insufficient and inadequate, and comprise immunosuppressive drugs, such as steroid or cyclosporine, intravenous immunoglobulin or plasma exchange. These have shown variable success in case reports, with a presumably temporary effect, but with major side effects.

METHODS

We assessed the effects of oxcarbazepine treatment in 67 cases of cryoglobulinemia related neuropathy, who did not respond to either steroid or Gabapentin, or Pregabalin. Oxcarbazepine was chosen based on the promising preliminary results.

RESULTS

Patients treated with Oxcarbazepine showed a rapid, discrete and persistent relief of polyneuropathic signs, without consistent side effects, and with a limited interaction with concomitant drugs.

CONCLUSIONS

These data favor the use of oxcarbazepine as a useful tool in the management of neuropathic pain associated with Hepatitis-C cryoglobulin neuropathy.

Hepatitis C virus and human T-cell lymphotropic virus type 1 co-infection: impact on liver disease, virological markers, and neurological outcomes

OBJECTIVES

Human T-cell lymphotropic virus type 1 (HTLV-1) infection is associated with neurological abnormalities, such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and peripheral neuropathy (PN). Hepatitis C virus (HCV) infection is the leading cause of chronic liver disease worldwide, and causes PN in approximately 9% of patients. Because the interplay between these potentially neuropathogenic viruses in the same individual is still poorly understood, the clinical and laboratory outcomes of co-infected patients were evaluated and compared with those of controls.

METHODS

The prevalence rates of neurological and laboratory abnormalities were evaluated in HCV/HTLV-1 co-infected patients (n=50), and in subjects with single HCV (n=46) or HTLV-1 (n=150) infection.

RESULTS

A higher frequency of isolated PN was present in HCV-infected patients; this was not associated with cryoglobulinemia. No difference was found in the frequency of PN or HAM/TSP when co-infected subjects were compared to singly infected subjects. Hepatic involvement was present in HCV-infected subjects, as shown by increased levels of serum alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, and bilirubin, in addition to thrombocytopenia. On the other hand, HCV/HTLV-1 co-infected individuals presented a better prognosis for hepatic involvement when compared with singly HCV-infected subjects.

CONCLUSIONS

These data suggest that HCV/HTLV-1 co-infection does not mutualistically alter the outcome with regard to neurological manifestations. Nonetheless, changes in the immunological environment induced by HTLV-1 infection could lead to a reduction in hepatic damage, even without significant HCV clearance.

Infectious neuropathies

PURPOSE OF REVIEW

Infectious neuropathies are heterogeneous neuropathies with multiple causes. They still represent an important world health burden and some of them have no current available therapy.

RECENT FINDINGS

Leprosy incidence has decreased by 50% during the last years, but leprosy-related neuropathies still cause severe disability. The pure neuritic leprosy is a diagnostic challenge that may require nerve biopsy or nerve aspiration cytology. The treatment itself may lead to a 'reversal reaction', which further causes injuries to the nerve. HCV-related neuropathies may be related or not to the presence of cryoglobulins. The absence of vasculitis, the most frequent form is a peripheral sensory neuropathy involving small nerve fibers, and more accurately diagnosed by pain-related evoked potentials. HIV-related neuropathy has become the major neurological complication of HIV infection. Both HIV-induced neuropathy and antiretroviral toxic neuropathy are clinically indistinguishable. The existence of an isolated chronic polyneuropathy due to Borrelia burgdorferi remains highly controversial. Lastly, an active infectious ganglioneuritis caused by varicella zoster virus, producing shingles, is the most frequent infectious neuropathy in the world and may cause various neurological complications. Zoster sine herpete remains frequently undiagnosed.

SUMMARY

Recent data have improved our knowledge and diagnostic tools of infectious neuropathies. Treatment of the injured nerves is not yet available, and prevention and rapid diagnosis remain the main priorities for the clinician.

Neurological complications of hepatitis C infection

Though well-known as a cause of liver disease, Hepatitis C virus infection is emerging as a cause of a variety of peripheral and central nervous system disorders. The virus causes chronic persistent infection with complex immune responses in the majority of individuals. Viral infection may have the potential to generate neurological illness through direct infection of neural cells or through immune-mediated mechanisms, including enhancement of autoimmune responses. Moreover, the mainstay of antiviral treatment of hepatitis C infection, interferon-alpha, is itself associated with neurological morbidity. Thus neurologists are increasingly faced with diagnosing or even predicting a wide spectrum of neurological complications of hepatitis C infection and/or its treatment.

HCV-related nervous system disorders

Chronic infection with hepatitis C virus (HCV) is associated with a wide spectrum of extrahepatic manifestations, affecting different organ systems. Neurological complications occur in a large number of patients and range from peripheral neuropathy to cognitive impairment. Pathogenetic mechanisms responsible for nervous system dysfunction are mainly related to the upregulation of the host immune response with production of autoantibodies, immune complexes, and cryoglobulins. Alternative mechanisms include possible extrahepatic replication of HCV in neural tissues and the effects of circulating inflammatory cytokines and chemokines.

Acute combined central and peripheral demyelination showing anti-aquaporin 4 antibody positivity

Neuromyelitis optica spectrum disorder (NMOSD) is characterized by optic neuritis or transverse myelitis with anti-aquaporin 4 (AQP4) antibodies (1). We herein present the case of a patient with NMOSD who also was affected with peripheral neuropathy. A 58-year-old woman developed gait disturbance and sensory impairment in the lower limbs. She exhibited longitudinally extensive transverse myelitis with anti-AQP4 antibodies. Nerve conduction studies showed demyelinating changes. Laboratory findings showed hepatitis-C virus (HCV) infection. Her peripheral neuropathy improved after immunotherapy. There have been no previous reports of NMO or NMOSD associated with neuropathy. The HCV infection or undetermined humoral factors other than the anti-AQP4 antibodies may have caused her peripheral neuropathy.