Central nervous system vasculitis associated with hepatitis C virus infection: a brain MRI-supported diagnosis

High-resolution intracranial vessel wall imaging in cerebral viral infections evaluations

Purpose

Vascular complications can be seen in various viral CNS infections. Variable neuro-imaging findings have been described in the literature elucidating the parenchymal changes with vascular involvement. Vessel wall imaging (VWI) can help to detect these vascular involvements. We aimed to describe the role and usefulness of VWI in the evaluation of various viral CNS infections.

Methods

In this prospective study, we included 15 cases of various diagnosed viral CNS infections (varicella, HIV encephalopathy, HSV encephalitis, Japanese encephalitis, dengue, COVID-19). VWI and time-of-flight MR angiography (TOF MRA) were included in imaging protocol. All cases were evaluated for the presence of cerebral parenchymal changes, vascular enhancement, and vascular stenosis.

Results

We found infarctions in all 5 cases of varicella, 1 case of HIV encephalopathy, and 1 case of COVID-19 encephalopathy. All these cases also showed vascular enhancement and stenosis on VWI. The rest of the cases, including 1 case of HIV encephalopathy, 3 cases of herpes encephalitis, 2 cases of dengue, and 2 cases of Japanese encephalitis did not have any vascular complication, and also did not show vascular enhancement or stenosis.

Conclusion

VWI can be useful in the detection of vascular involvement in various viral infections of CNS which show a relatively higher cerebrovascular complication rate like varicella, HIV encephalopathy, and COVID-19. However, VWI may not be useful in the routine evaluation of other viral infections like herpes, dengue, and Japanese encephalitis, which have a very low rate of cerebrovascular complication rate.

Vessel wall MR imaging of central nervous system vasculitis: a systematic review

PURPOSE

Beyond vessel wall enhancement, little is understood about vessel wall MR imaging (VW-MRI) features of vasculitis affecting the central nervous system (CNS). We reviewed vessel wall MR imaging patterns of inflammatory versus infectious vasculitis and also compared imaging patterns for intracranial versus extracranial arteries of the head and neck.

METHODS

Studies reporting vasculitis of the CNS/head and neck and included MR imaging descriptions of vessel wall features were identified by searching PubMed, Scopus, Cochrane, Web of Science, and EMBASE up to June 10, 2020. From 6065 publications, 115 met the inclusion criteria. Data on study characteristics, vasculitis type, MR details, and VW-MRI descriptions were extracted.

RESULTS

Studies used VW-MRI for inflammatory (64%), infectious (17%), or both inflammatory and infectious vasculitides (19%). Vasculitis affecting intracranial versus extracranial arteries were reported in 58% and 39% of studies, respectively. Commonly reported VW-MRI features were vessel wall enhancement (89%), thickening (72%), edema (10%), and perivascular enhancement (16%). Inflammatory vasculitides affecting the intracranial arteries were less frequently reported to have vessel wall thickening (p = 0.006) and perivascular enhancement (p = 0.001) than extracranial arteries. Varicella zoster/herpes simplex vasculitis (VZV/HSV, 45%) and primary angiitis of the CNS (PACNS, 22%) were the most commonly reported CNS infectious and inflammatory vasculitides, respectively. Patients with VZV/HSV vasculitis more frequently showed decreased or resolution of vessel wall enhancement after therapy compared to PACNS (89% versus 59%).

CONCLUSIONS

To establish imaging biomarkers of vessel wall inflammation in the CNS, VW-MRI features of vasculitis accounting for disease mechanism and anatomy should be better understood.

Cognitive, neurological and psychiatric disorders occurring in Hepatitis C Virus infection

Chronic Hepatitis C is associated with many extrahepatic manifestations. Central nervous system is frequently involved, but the pathophysiological mechanisms are not fully understood. Local and systemic inflammation, ischemia, immune-mediated phenomena have been described in this context. Clinical manifestations include cognitive alterations, stroke, depression and demyelinating phenomena. It is unclear if cognitive deficits can be improved or resolved with viral eradication and to understand this, could have important therapeutical implications.

Cognitive impairments in HCV infection: From pathogenesis to neuroimaging

Extrahepatic manifestations of hepatitis C virus (HCV) infection, in particular cognitive impairments, can be present in the absence of clinical liver dysfunction. Executive memory, attention, and concentration are cognitive domains that are most frequently affected. Microstructural and functional changes in cortical gray matter and basal ganglia associate these neuropsychiatric changes in early HCV infection. No study has covered the relationship between imaging features of HCV-related cognitive impairment and HCV pathology. Herein we summarize evidence suggesting a direct pathology of HCV in microglia, astrocytes, and microvascular endothelial cells, and a neuroinflammatory response in HCV-related cognitive decline. Lipoproteins and their receptors mediate HCV infectivity in the central nervous system and confer susceptibility to HCV-related cognitive decline. Magnetic resonance spectroscopy has revealed changes compatible with reactive gliosis and microglial activation in basal ganglia, frontal and occipital white matter, in the absence of cirrhosis or hepatic encephalopathy. Similarly, diffusion imaging shows evidence of structural disintegrity in the axonal fibers of white matter tracts associated with temporal and frontal cortices. We also discuss the cognitive benefits and side-effects of the two most popular therapeutic protocols interferon-based therapy and interferon-free therapy using direct acting anti-virals. Evidences support a network-based pattern of disruption in functional connectivity in HCV patients and a common neuronal substrate for HCV-related and interferon-therapy-associated cognitive decline. These evidences might help identify patients who benefit from either interferon-based or interferon-free treatment regimen.

Stroke Characteristics, Risk Factors, and Outcomes in Transgender Adults: A Case Series

OBJECTIVES

To describe the clinical characteristics and risk factors of male-to-female transgender (transwomen) patients with acute stroke.

METHODS

The study population included all patients admitted for stroke at San Francisco General Hospital from October 1, 2010 through August 31, 2017 who self-identified as transwomen. Patient charts were reviewed by the study coauthors for demographics, stroke risk factors, stroke characteristics, and clinical outcomes. Means, percentiles, and ranges were calculated.

RESULTS

Eight transwomen (average age, 50±9 y; range, 38 to 61 y) were admitted for stroke (average NIHSS, 8; range, 0 to 27). The majority of patients presented subacutely. The most common type of stroke was ischemic stroke (4, 50%), followed by intracerebral hemorrhage (2, 22%), transient ischemic attack (1, 13%), and concurrent ischemic stroke with subarachnoid hemorrhage (1, 13%). While traditional stroke risk factors were present, these patients also disproportionally had alternative risk factors: stimulant use (5, 63%), tobacco use (5, 63%), hepatitis C (5, 63%), human immunodeficiency virus (3, 38%), and prior stroke or transient ischemic attack (2, 25%). Six patients (75%) used estradiol (oral or injection) or conjugated estrogen as part of gender-affirming treatment at the time of stroke; one patient used estrogen remotely. Only 2 patients (33%) were prescribed their hormone therapy on discharge.

CONCLUSIONS

Understanding unique vulnerabilities of the transgender community for cerebrovascular events is essential to provide culturally appropriate counseling for harm reduction.

Imaging of cerebrovascular complications of infection

Cerebrovascular complications may occur in infectious diseases in the setting of infective endocarditis, central nervous system (CNS) infections, systemic bacteremia and sepsis. Cerebrovascular complications of infections include vasculitis, mycotic aneurysms, and thrombophlebitis. Infectious vasculitis of the CNS may cause cerebral hemorrhage, infarction or ischemia. Ruptured aneurysms may endanger the patient's life. Infectious thrombophlebitis may cause intracranial pressure to increase and lead to cerebral hemorrhage. These cerebrovascular complications are associated with a poor prognosis and often cause irreversible neurological deficits. Cerebrovascular events secondary to infection are not easily distinguishable from the more common cerebral infarct and non-infectious vasculitis. In addition, the clinical manifestations of cerebrovascular complications of infections are non-specific and highly variable. Therefore, early imaging, antibiotics, and anticoagulation may be lifesaving the patient's life and prevent disability. The main focus of this article is to review imaging analysis of the cerebrovascular complications of infections and imaging features that help differentiate them from non-infectious vascular diseases.

Values of magnetic Resonance imaging and Cerebrospinal fluid analysis in the diagnosis of Central Nervous System associated infectious diseases

Objective:

To discuss the roles of magnetic resonance imaging (MRI) and cerebrospinal fluid analysis in the identification of central nervous system associated infection and provide a reference for the diagnosis and treatment of central nervous system associated infectious diseases.

Methods:

Seventy-six patients who developed central nervous system infection and were admitted into the Henan People’s Hospital between June 2014 and October 2015 were randomly selected as an observation group. Patients in the observation group were subdivided according to purulent meningitis, cryptococcal meningitis, viral meningitis and tubercular meningitis. Moreover, 35 headache patients who were admitted in the same period were selected as a control group. The MRI results and cerebrospinal fluid examination indicators were compared between the two groups.

Results:

MRI results suggested that the positive rate of the observation group was 96.05% (73/76), much higher than 8.57% in the control group (3/35), and the difference had statistical significance (P<0.05). The analysis results of cerebrospinal fluid demonstrated that the concentration of lactate dehydrogenase (LDH) in the cerebrospinal fluid of the patients with tubercular meningitis was the highest, the concentration of creatine kinase (CK) in the cerebrospinal fluid of the patients with purulent meningitis was the highest, and the concentration of lactic acid (LA) in the cerebrospinal fluid of the patients with tubercular meningitis and purulent meningitis was higher than that of the other patients; the differences were statistically significant (P<0.05). The analysis on the diagnostic efficacy of MRI in combination with cerebrospinal fluid analysis suggested that the sensitivity of the diagnostic scheme was high in diagnosing meningitis except purulent meningitis, and the specificity and accuracy of the scheme was high in diagnosing meningitis except cryptococcal meningitis.

Conclusion:

MRI in combination with cerebrospinal fluid analysis is effective in diagnosing central nervous system associated infectious diseases. It can also effectively identify the types of infection besides improving accuracy, which provides an important reference for clinical treatment.

Magnetic resonance imaging in central nervous system vasculitis in a patient affected by crioglobulin-negative hepatitis C virus infection: A likely correlation

A 56-year-old man with behavioural disorders and facial-brachio-crural right hemiparesis presented with a brain lesion studied with computed tomography, magnetic resonance imaging and brain biopsy, leading to the diagnosis of cerebral vasculitis. Hepatitis C virus (HCV) infection in a phase of activity, without cryoglobulins, was also detected. Brain biopsy, laboratory analysis and response to a specific therapy supported the diagnosis of central nervous system vasculitis that was HCV related.

Immunologic Cerebral Vasculitis and Extrapulmonary Tuberculosis: An Uncommon Association

Infection can cause cerebral vasculitis not only by direct invasion of the vessel wall, but by immune complex deposition, or through secondary cryoglobulineamia. There are also two types of cerebral vasculitis associated with tuberculosis (TB). In TB treatment, cerebral vasculitis caused by immunologic injury received little attention than vasculitis due to direct invasion of TB infection. We report a case in a young woman who presented with fever, generalized lymphadenopathy, stroke-like events, movement disorder and coma, which was found to be active, lymph node TB with immunologic cerebral vacuities without tuberculosis meningitis.

Chronic hepatitis C virus infection and neurological and psychiatric disorders: An overview

Hepatitis C virus (HCV) infection is considered a systemic disease because of involvement of other organs and tissues concomitantly with liver disease. Among the extrahepatic manifestations, neuropsychiatric disorders have been reported in up to 50% of chronic HCV infected patients. Both the central and peripheral nervous system may be involved with a wide variety of clinical manifestations. Main HCV-associated neurological conditions include cerebrovascular events, encephalopathy, myelitis, encephalomyelitis, and cognitive impairment, whereas “brain fog”, depression, anxiety, and fatigue are at the top of the list of psychiatric disorders. Moreover, HCV infection is known to cause both motor and sensory peripheral neuropathy in the context of mixed cryoglobulinemia, and has also been recently recognized as an independent risk factor for stroke. These extrahepatic manifestations are independent of severity of the underlying chronic liver disease and hepatic encephalopathy. The brain is a suitable site for HCV replication, where the virus may directly exert neurotoxicity; other mechanisms proposed to explain the pathogenesis of neuropsychiatric disorders in chronic HCV infection include derangement of metabolic pathways of infected cells, alterations in neurotransmitter circuits, autoimmune disorders, and cerebral or systemic inflammation. A pathogenic role for HCV is also suggested by improvement of neurological and psychiatric symptoms in patients achieving a sustained virologic response following interferon treatment; however, further ad hoc trials are needed to fully assess the impact of HCV infection and specific antiviral treatments on associated neuropsychiatric disorders.