Chikungunya Virus Infection Associated with Encephalitis and Anterior Uveitis

Systemic and Ophthalmic Manifestations of Chikungunya Fever

PURPOSE

Chikungunya is a re-emerging viral infection across the globe. The purpose of this article is to review the systemic and ophthalmic manifestations associated with chikungunya fever.

METHOD

A review of literature was conducted using online databases.

RESULTS

In this report, we have reviewed the presently available literature on uveitis caused by chikungunya and highlighted the current knowledge of its clinical manifestations, imaging features, laboratory diagnostics, and the available therapeutic modalities from the systemic and ophthalmic standpoint.

CONCLUSIONS

Ocular involvement in chikungunya infection may occur at the time of systemic manifestations or it may occur as a delayed presentation many weeks after the fever. Treatment relies on a supportive therapy for systemic illness. Treatment of ocular manifestation depends on the type of manifestations and usually includes a combination of topical and oral steroids.

The association of uveitis with hepatitis B and hepatitis C viruses: a large-scale population-based study

PURPOSE

To examine the association of uveitis with hepatitis B (HBV) and hepatitis C (HCV) chronic infections METHOD: This is a population-based cross-sectional study. The study encompassed 13,183 consecutive patients with uveitis and 65,331control subjects. The prevalence of chronic HBV and HCV infections was compared between patients diagnosed with uveitis and age-, sex-, and ethnicity-matched controls. Lifetime prevalence rates of HBV and HCV were calculated for patients with uveitis and control individuals. Odds ratio (OR) for HBV and HCV was evaluated across different strata.

RESULTS

The lifetime prevalence rate of chronic HBV infection was greater in patients with uveitis than in controls (1.2% vs. 0.8%, respectively; P < 0.001). The association of HBV with uveitis was statistically significant among individuals older than 40 years of age, both sexes, and individuals of Jewish ethnicity. The lifetime prevalence of HCV was comparable between patients with uveitis and controls (0.8% vs. 0.7%, respectively; P = 0.189). Thus, no independently significant association was found between uveitis and HCV (fully-adjusted OR, 1.15; 95% CI, 0.93-1.42; P = 0.211).

CONCLUSIONS

Uveitis is associated with HBV. The association was more prominent among older and Jewish patients. Patients with uveitis may benefit from screening for HBV. An association between uveitis and HCV has not been found.

Chikungunya Encephalitis: an Inconsistently Reported Headache and Cause of Death in Patients with Pre-Existing Conditions

Chikungunya virus (CHIKV) is an alphavirus of the family Togaviridae with outbreaks occurring across Africa, Asia, parts of Europe, and South and Central America. There are three main lineages of CHIKV, including the West African lineage, the East Central South African (ECSA) lineage, and the Asian lineage. While CHIKV infection usually results in a self-limited febrile illness, there have been reports of concerning neurological manifestations, including encephalitis. Herein we discuss findings of over 700 cases of CHIKV encephalitis and risk factors for death. Additionally, we examined the genotypes of CHIKV associated with encephalitis and found that both the Asian and ECSA lineages were responsible for encephalitis but not the West African lineage. Protein analysis of consensus sequences of CHIKV strains associated with encephalitis identified mutations in the nsP1, nsP2, and nsP3 proteins. Reports and manuscripts of CHIKV encephalitis were inconsistent in reporting viral, demographic, and clinical features which complicated the delineation of risk factors associated with the disease and viral evolution. As climate change contributes to the range expansion of natural vectors, it is important for researchers and clinicians to consistently report patient and viral data to facilitate research and countermeasures for the ecology and epidemiology of CHIKV due to the lack of a targeted treatment or vaccine.

Viral and Prion Infections Associated with Central Nervous System Syndromes in Brazil

Virus-induced infections of the central nervous system (CNS) are among the most serious problems in public health and can be associated with high rates of morbidity and mortality, mainly in low- and middle-income countries, where these manifestations have been neglected. Typically, herpes simplex virus 1 and 2, varicella-zoster, and enterovirus are responsible for a high number of cases in immunocompetent hosts, whereas other herpesviruses (for example, cytomegalovirus) are the most common in immunocompromised individuals. Arboviruses have also been associated with outbreaks with a high burden of neurological disorders, such as the Zika virus epidemic in Brazil. There is a current lack of understanding in Brazil about the most common viruses involved in CNS infections. In this review, we briefly summarize the most recent studies and findings associated with the CNS, in addition to epidemiological data that provide extensive information on the circulation and diversity of the most common neuro-invasive viruses in Brazil. We also highlight important aspects of the prion-associated diseases. This review provides readers with better knowledge of virus-associated CNS infections. A deeper understanding of these infections will support the improvement of the current surveillance strategies to allow the timely monitoring of the emergence/re-emergence of neurotropic viruses.

Epidemiology of Viral Induced Anterior Uveitis

Purpose: Viral agents are the most common cause of infectious anterior uveitis worldwide. The purpose of this review is to analyze the frequency, gender and racial differences of viral anterior uveitis (VAU) in various populations.Methods: Systematized literature review of epidemiological reports of VAU cited in PubMed, EMBASE and the Cochrane Library database published until June 30th, 2020.Results: A total of 12 clinical studies on epidemiology of definite VAU and 36 clinical studies of presumed VAU were identified. Members of Herpesviridae family represent the most common causes of VAU. Other less frequently reported causes, such as rubella and endemic viruses (HTLV-1, Chikungunya, Dengue, Ebola, Zika virus) were also analyzed.Conclusion: HSV, VZV are prevalent worldwide. CMV is more frequent in Asia, and rubella in the West. However, due to globalization and air travel, HTLV-1, Chikungunya, Dengue and Ebola may become important causes of VAU across the world.

Role of MicroRNAs in Bone Pathology during Chikungunya Virus Infection

Chikungunya virus (CHIKV) is an alphavirus, transmitted by mosquitoes, which causes Chikungunya fever with symptoms of fever, rash, headache, and joint pain. In about 30%-40% of cases, the infection leads to polyarthritis and polyarthralgia. Presently, there are no treatment strategies or vaccine for Chikungunya fever. Moreover, the mechanism of CHIKV induced bone pathology is not fully understood. The modulation of host machinery is known to be essential in establishing viral pathogenesis. MicroRNAs (miRNAs) are small non-coding RNAs that regulate major cellular functions by modulating gene expression. Fascinatingly, recent reports have indicated the role of miRNAs in regulating bone homeostasis and altered expression of miRNAs in bone-related pathological diseases. In this review, we summarize the altered expression of miRNAs during CHIKV pathogenesis and the possible role of miRNAs during bone homeostasis in the context of CHIKV infection. A holistic understanding of the different signaling pathways targeted by miRNAs during bone remodeling and during CHIKV-induced bone pathology may lead to identification of useful biomarkers or therapeutics.

Acute bilateral granulomatous anterior uveitis as an extra-hepatic manifestation of hepatitis A virus (HAV) infection: a case report

Anterior uveitis (AU) is the most common form of uveitis. The differential diagnosis of AU is broad, ranging from infectious etiologies to autoimmune causes. However, approximately half remain idiopathic. Infections are the vision-threatening causes of AU which should be ruled out by history taking and detailed physical examination combined with guided work up. We report a rare case of bilateral granulomatous AU following hepatitis A virus (HAV) infection in an immunocompetent patient. A 35-year-old male presented to our center with a chief complaint of pain and redness in both eyes 3 days prior to the presentation. The patient’s medical and drug history was unremarkable. He had a history of river water consumption 20 days prior to presentation. The patient was diagnosed with acute bilateral granulomatous AU. All routine work up to investigate the etiology of the disease was unremarkable, except for the serology of acute HAV infection, which was positive. The patient was managed with the topical steroid and cycloplegic for 2 weeks with no recurrence at one-year follow up. Extra-hepatic complications of HAV were reported in previous studies including arthritis, urticaria, myocarditis, nephritis, and myositis. The mechanism of extra-hepatic complication of hepatitis A is unknown; however, immune-complex deposition is most likely the etiological cause. Our report represents a rare case of sudden onset with limited duration granulomatous AU as a presenting manifestation of HAV infection. Previous studies do not provide a direct evidence of granulomatous AU associated with the HAV infection.

Immunopathogenesis of alphaviruses

Alphaviruses, members of the enveloped, positive-sense, single-stranded RNA Togaviridae family, represent a reemerging public health threat as mosquito vectors expand into new geographic territories. The Old World alphaviruses, which include chikungunya virus, Ross River virus, and Sindbis virus, tend to cause a clinical syndrome characterized by fever, rash, and arthritis, whereas the New World alphaviruses, which consist of Venezuelan equine encephalitis virus, eastern equine encephalitis virus, and western equine encephalitis virus, induce encephalomyelitis. Following recovery from the acute phase of infection, many patients are left with debilitating persistent joint and neurological complications that can last for years. Clues from human cases and studies using animal models strongly suggest that much of the disease and pathology induced by alphavirus infection, particularly atypical and chronic manifestations, is mediated by the immune system rather than directly by the virus. This review discusses the current understanding of the immunopathogenesis of the arthritogenic and neurotropic alphaviruses accumulated through both natural infection of humans and experimental infection of animals, particularly mice. As treatment following alphavirus infection is currently limited to supportive care, understanding the contribution of the immune system to the disease process is critical to developing safe and effective therapies.

GloPID-R report on Chikungunya, O'nyong-nyong and Mayaro virus, part I: Biological diagnostics

The GloPID-R (Global Research Collaboration for Infectious Disease Preparedness) Chikungunya (CHIKV), O'nyong-nyong (ONNV) and Mayaro virus (MAYV) Working Group is investigating the natural history, epidemiology and medical management of infection by these viruses, to identify knowledge gaps and to propose recommendations for direct future investigations and rectification measures. Here, we present the first report dedicated to diagnostic aspects of CHIKV, ONNV and MAYV. Regarding diagnosis of the disease at the acute phase, molecular assays previously described for the three viruses require further evaluation, standardized protocols and the availability of international standards representing the genetic diversity of the viruses. Detection of specific IgM would benefit from further investigations to clarify the extent of cross-reactivity among the three viruses, the sensitivity of the assays, and the possible interfering role of cryoglobulinaemia. Implementation of reference panels and external quality assessments for both molecular and serological assays is necessary. Regarding sero-epidemiological studies, there is no reported high-throughput assay that can distinguish among these different viruses in areas of potential co-circulation. New specific tools and/or improved standardized protocols are needed to enable large-scale epidemiological studies of public health relevance to be performed. Considering the high risk of future CHIKV, MAYV and ONNV outbreaks, the Working Group recommends that a major investigation should be initiated to fill the existing diagnostic gaps.

Infectious uveitis: an Asian perspective

Several intraocular infections can present with protean manifestations posing major diagnostic and management challenges. Infections such as tuberculosis, dengue and chikungunya fever have continued to remain major endemic diseases that are associated with uveitis in the Asia Pacific region. These entities often require a high index of clinical suspicion and laboratory analysis including assays of ocular fluids and/or tissues for confirmation of the diagnosis. Infectious uveitis caused by tuberculosis, dengue and chikungunya can present with characteristic clinical features and imaging findings on ancillary investigations; that may provide clue to the early diagnosis. Use of modern imaging modalities such as enhanced-depth imaging optical coherence tomography, optical coherence tomography angiography and ultra-wide field fundus photography greatly aid in the evaluation of these conditions. In the current review, we have discussed the epidemiology, clinical phenotypes, imaging characteristics, diagnosis and management of uveitis caused by tuberculosis, dengue and chikungunya.

The neurological complications of chikungunya virus: A systematic review

We performed a systematic review on the neurological complications of chikungunya virus. Such complications are being reported increasingly, owing primarily to the scale of recent epidemics but also to a growing understanding of the virus' neurovirulence. We performed a thorough literature search using PubMed and Scopus databases, summating the data on all published reports of neurological disease associated with chikungunya virus. We appraised the data for each major condition in adults, children, and neonates, as well as evaluating the latest evidence on disease pathogenesis and management strategies. The review provides a comprehensive summary for clinicians, public health officials, and researchers tackling the challenges associated with this important emerging pathogen.