Detection of encephalitis-causing viruses reveals predominance of chikungunya virus in the state of Bahia, Brazil.

OBJECTIVES: Encephalitis is a severe neurological syndrome for which herpesvirus and enteroviruses are the most common etiological agents. Arboviruses, a wildly diverse group of pathogens, are also critical epidemiological agents associated with encephalitis. In Brazil, little is known about the causative agents of encephalitis. METHODS: We conducted a hospital surveillance for encephalitis between 2020 and 2022. Molecular (RT-PCR and qPCR) and serological (virus-specific IgM and viral antigens) techniques were performed in cerebrospinal fluid and serum samples obtained from study participants. RESULTS: In the 43 participants evaluated, the etiologic agent or the presence of IgM was detected in 16 (37.2%). Nine (20.9%) cases were positive for chikungunya virus (CHIKV), three (7.0%) for dengue virus, two (4.7%) for human adenovirus, one (2.3%) for varicella-zoster virus, and one (2.3%) for enterovirus. Whole-genome sequencing revealed that the CHIKV identified belongs to the East/Central/South African lineage. CONCLUSION: Herein, CHIKV is a common pathogen identified in encephalitis cases. Our results reinforce previous evidence that chikungunya represents a significant cause of encephalitis during CHIKV outbreaks and epidemics and add to existing information on the epidemiology of encephalitis in Brazil.

Development of a new non invasive prognostic stroke scale (NIPSS) including triage elements for sleep apnea and peripheral artery disease.

BACKGROUND: Although sleep apnea and peripheral artery disease are prognostic factors for stroke, their added benefit in the acute stage to further prognosticate strokes has not been evaluated. OBJECTIVES: We tested the accuracy in the acute stroke stage of a novel score called the Non-Invasive Prognostic Stroke Scale (NIPSS). PATIENTS AND METHODS: Prospective cohort with imaging-confirmed ischemic stroke. Clinical data, sleep apnea risk score (STOPBANG) and blood pressure measures were collected at baseline. Primary outcome was the 90-day modified Rankin Scale (mRS), with poor outcome defined as mRS 3-6. Area under the ROC curve (AUC) was calculated for NIPSS and compared to six other stroke prognostic scores in our cohort: SPAN-100 index, S-SMART, SOAR, ASTRAL, THRIVE, and Dutch Stroke scores. RESULTS: We enrolled 386 participants. After 90 days, there were 56% with poor outcome, more frequently older, female predominant and with higher admission National Institute of Health Stroke Scale (NIHSS). Four variables remained significantly associated with primary endpoint in the multivariable model: age (OR 1.87), NIHSS (OR 7.08), STOPBANG category (OR 1.61), and ankle-braquial index (OR 2.11). NIPSS AUC was 0.86 (0.82-0.89); 0.83 (0.79-0.87) with bootstrapping. When compared to the other scores, NIPSS, ASTRAL, S-SMART and DUTCH scores had good abilities in predicting poor outcome, with AUC of 0.86, 0.86, 0.83 and 0.82, respectively. THRIVE, SOAR and SPAN-100 scores were fairly predictive. DISCUSSION AND CONCLUSIONS: Non-invasive and easily acquired emergency room data can predict clinical outcome after stroke. NIPSS performed equal to or better than other prognostic stroke scales.

Guillain-Barré Syndrome and Miller Fisher Syndrome in Association With an Arboviral Outbreak: A Brazilian Case Series.

Introduction: Guillain-Barré syndrome (GBS) in association with arboviruses, such as Zika, chikungunya, and dengue, has been previously documented; however, Miller-Fisher Syndrome (MFS) and other GBS subtypes are rarely reported. Methods: We identified a series of GBS and MFS cases that were followed during the Zika virus outbreak in Salvador, Brazil (2015-2016). Blood and CSF samples were collected for virus diagnosis. In addition, serological studies to verify previous arboviral infection and electromyography (EMG) were performed. Results: Of the 14 patients enrolled, 10 were diagnosed with GBS, including three GBS subtypes (two cases of bifacial weakness with paresthesia and one case of paraparetic GBS), and four as MFS. IgM antibodies against one or more of three arboviruses were present in 11 (78.6%) patients: anti-zika IgM positivity in eight (57%), anti-Chikungunya IgM in three (21%), and anti-Dengue in one (7%) individual. A single case was positive for both anti-Dengue IgM and anti-Chikungunya IgM, suggesting co-infection. EMG revealed an AIDP pattern in all nine patients analyzed. Conclusion: The current case series contributes to our knowledge on the clinical presentation of arbovirus-associated GBS and its subtypes, including MFS, and serves as an alert to clinicians and other healthcare professionals in regions affected by arbovirus outbreaks. We highlight the importance of recognizing arboviruses in diagnosing GBS and its subtypes.

Opsoclonus-myoclonus-ataxia syndrome associated with chikungunya and dengue virus co-infection.

Opsoclonus-myoclonus-ataxia syndrome (OMAS) is a rare neurological disorder characterized by irregular multidirectional eye movements, myoclonus, cerebellar ataxia, sleep disturbances, and cognitive dysfunction. Although most commonly related to paraneoplastic syndrome, this condition has occasionally been described following infectious illnesses. This article reports the first case of OMAS in association with chikungunya and dengue virus co-infection. The genetic analysis identified chikungunya virus of East/Central/South African genotype and dengue serotype 4 virus of genotype II. This report represents an unusual clinical syndrome associated with viral co-infection and reinforces the need for clinical vigilance with regard to neurological syndromes in the context of emergent arboviruses.

Guillain-Barré Syndrome After Zika Virus Infection in Brazil.

Zika virus (ZIKV) is an emerging flavivirus, which has caused a widespread outbreak in the Americas. Shortly after its introduction in 2015, a cluster of cases with Guillain-Barré syndrome was detected in Brazil. Herein, we describe two cases from the city of Salvador, who developed ascending paresis after an acute exanthematous illness. The patients were admitted to the intensive care unit with tetraparesis and cranial nerve palsy, which resolved after intravenous administration of human immunoglobulin. Serological evaluation detected IgM-specific ZIKV antibodies. In regions of Zika virus transmission, health-care workers must be aware of the potential severe neurological complications associated with ZIKV infection and be prepared to provide prompt diagnosis, treatment, and supportive care.