Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system caused by the human polyomavirus JC virus. PML mainly occurs in immunocompromised patients. A 36-year-old man with no evidence of immunosuppresion presented seizures. MRI scans of brain showed multifocal lesions in the cerebral white matters. JC virus DNA was positive in the cerebrospinal fluid examined by JC virus PCR. We report a rare case of PML presenting as viral encephalitis that occurred in a healthy adult person.
Adult ; Brain ; Central Nervous System ; Demyelinating Diseases ; DNA ; Encephalitis, Viral ; Humans ; Immunocompromised Host ; JC Virus ; Leukoencephalopathy, Progressive Multifocal ; Magnetic Resonance Imaging ; Polymerase Chain Reaction ; Seizures ; Viruses

Venezuelan equine encephalitis (VEE) is a zoonotic disease caused by the Venezuelan equine encephalitis virus (VEEV) complex. This disease has not yet been reported in China, and it is therefore essential to establish a rapid and accurate method for detection of the virus in order to prevent and control this disease. In this study, a one-step real-time quantitative RT-PCR method was developed for the detection of the VEEV complex. A pair of specific primers and a Taqman probe were designed corresponding to a conserved region of the VEEV gene nspl, allowing the detection of all known strains of different sub- types of the virus. Using RNA synthesized by in vitro transcription as template, the sensitivity of this method was measured at 3.27 x 10(2) copies/microL. No signal was generated in response to RNA from Chikungunya virus (CHIKV), nor to RNA encoding the nsp1 fragment of Eastern equine encephalitis virus (EE-EV) or Western equine encephalitis virus (WEEV), all of which belong to the same genus as VEEV. This indicates that the method has excellent specificity. These results show that this one-step real-time quantitative RT-PCR method may provide an effective tool for the detection of VEEV in China.
China ; DNA Primers ; genetics ; Encephalitis Virus, Venezuelan Equine ; classification ; genetics ; isolation & purification ; Encephalomyelitis, Venezuelan Equine ; virology ; Humans ; RNA, Viral ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; methods

In this review, we mainly focus on zoonotic encephalitides caused by arthropod-borne viruses (arboviruses) of the families Flaviviridae (genus Flavivirus) and Togaviridae (genus Alphavirus) that are important in both humans and domestic animals. Specifically, we will focus on alphaviruses (Eastern equine encephalitis virus, Western equine encephalitis virus, Venezuelan equine encephalitis virus) and flaviviruses (Japanese encephalitis virus and West Nile virus). Most of these viruses were originally found in tropical regions such as Africa and South America or in some regions in Asia. However, they have dispersed widely and currently cause diseases around the world. Global warming, increasing urbanization and population size in tropical regions, faster transportation and rapid spread of arthropod vectors contribute in continuous spreading of arboviruses into new geographic areas causing reemerging or resurging diseases. Most of the reemerging arboviruses also have emerged as zoonotic disease agents and created major public health issues and disease epidemics.
Africa ; Alphavirus* ; Animals, Domestic ; Arboviruses* ; Arthropod Vectors ; Asia ; Encephalitis ; Encephalitis Virus, Venezuelan Equine ; Encephalitis Virus, Western Equine ; Encephalitis Viruses ; Encephalomyelitis, Equine ; Epidemiology* ; Flaviviridae ; Flavivirus* ; Global Warming ; Humans ; Population Density ; Public Health ; South America ; Togaviridae ; Transportation ; Urbanization ; Zoonoses

PURPOSE: The option of selecting isotonic rather than hypotonic fluids for maintenance fluid in children has been advocated by some authors. Pneumonia and CNS infections are frequent clinical settings for acute hyponatremia because of nonosmotic anti-diuretic hormone stimuli in children. We conducted the present study to identify the incidence of hyponatremia in pneumonia and CNS infection of children and to determine the importance of maintenance intravenous fluid therapy regimen and other related factors. METHODS: The study included 1,992 patients admitted to the Department of Pediatrics at Pusan National University Children's Hospital between November 2008 and August 2011, who were diagnosed with pneumonia or CNS infections and checked for serum sodium concentration. Their clinical data including laboratory findings were reviewed retrospectively. RESULTS: During the study period, 218 patients were identified to have acute hyponatremia among 1,992 patients. The overall incidence of hyponatremia was 10.9%. The incidence of hyponatremia in encephalitis (37.3%) was highest and the incidence in bacterial meningitis (27.4%), viral meningitis (20.0%), bacterial pneumonia (11.1%), mycoplasma pneumonia (9.2%), and viral pneumonia (6.8%) were in descending order. The mean age was higher in hyponatremic patients than in isonatremic patients. The incidence of hyponatremia was higher in who had 0.18% NaCl in 5% dextrose (D5 0.18% NS) than 0.45% NaCl in 5% dextrose infusion (D5 1/2NS) (9.0% vs. 2.2%). SIADH was identified in 20.5% among hospital acquired hyponatremic patients after adequate evaluation for SIADH. CONCLUSION: We recommend D5 1/2NS rather than D5 0.18% NS as the maintenance fluid given to children with pneumonia or infectious CNS diseases.
Central Nervous System Diseases ; Child ; Encephalitis ; Fluid Therapy ; Glucose ; Humans ; Hyponatremia ; Inappropriate ADH Syndrome ; Incidence ; Meningitis ; Meningitis, Bacterial ; Meningitis, Viral ; Pediatrics ; Pneumonia ; Pneumonia, Bacterial ; Pneumonia, Mycoplasma ; Pneumonia, Viral ; Sodium

Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease of the central nervous system (CNS) that typically presents as a monophasic disorder associated with multifocal neurologic symptoms and encephalopathy. ADEM is considered an autoimmune disorder that is triggered by an environmental stimulus in genetically susceptible individuals. The diagnosis of ADEM is based on clinical and radiological features. Most children with ADEM initially present with fever, meningeal signs, and acute encephalopathy. The level of consciousness ranges from lethargy to frank coma. Deep and subcortical white-matter lesions and gray-matter lesions such as thalami and basal ganglia on magnetic resonance imaging (MRI) are associated with ADEM. In a child who presents with signs of encephalitis, bacterial and viral meningitis or encephalitis must be ruled out. Sequential MRI is required to confirm the diagnosis of ADEM, as relapses with the appearance of new lesions on MRI may suggest either multiphasic ADEM or multiple sclerosis (MS). Pediatric MS, defined as onset of MS before the age of 16, is being increasingly recognized. MS is characterized by recurrent episodes of demyelination in the CNS separated in space and time. The McDonald criteria for diagnosis of MS include evidence from MRI and allow the clinician to make a diagnosis of clinically definite MS on the basis of the interval preceding the development of new white matter lesions, even in the absence of new clinical findings. The most important alternative diagnosis to MS is ADEM. At the initial presentation, the 2 disorders cannot be distinguished with certainty. Therefore, prolonged follow-up is needed to establish a diagnosis.
Basal Ganglia ; Central Nervous System ; Child ; Coma ; Consciousness ; Demyelinating Diseases ; Diagnosis, Differential ; Encephalitis ; Encephalomyelitis, Acute Disseminated ; Fever ; Follow-Up Studies ; Humans ; Lethargy ; Magnetic Resonance Imaging ; Meningitis, Viral ; Multiple Sclerosis ; Neurologic Manifestations ; Recurrence

Three dimensional structures of envelope protein from Korean isolates and Nakayama-NIH strain of Japanese encephalitis virus (JEV) were deduced by a computer program (HyperChem 4.0 Chemplus 1.0) based on the data of the three dimentional structure of Tick-borne encephalitis virus. In the three dimensional structure of envelope protein, neutralizing epitope and T-helper cell recognition site of C-terminal region of Korean isolates were structually similar to those of Nakayama-NIH but the N-terminal region was not. Korean JE isolates were compared with Nakayama-NIH strain by using cross-neutralization antibody test. Neutralizing activities of Korean isolates derived from guinea pigs were higher than those of Nakayama-NIH strain against Korean isolates, although the polyclonal antibody titers of Nakayama-NIH showed 1:160 to 1:640 against Korean isolates. According to the results from three dimentional structures and cross-neutralization analyses, the antigenic difference between Korean JE isolates and Nakayama-NIH strain may be dependent on structural difference of envelope protein.
Animals ; Encephalitis Virus, Japanese ; Encephalitis Viruses* ; Encephalitis Viruses, Tick-Borne ; Encephalitis* ; Guinea Pigs ; Korea*

Various new technologies have been applied for developing vaccines against various animal diseases. Virus-like particle (VLP) vaccine technology was used for manufacturing the porcine circovirus type 2 and RNA particle vaccines based on an alphavirus vector for porcine epidemic diarrhea (PED). Although VLP is classified as a killed-virus vaccine, because its structure is similar to the original virus, it can induce long-term and cell-mediated immunity. The RNA particle vaccine used a Venezuela equine encephalitis (VEE) virus gene as a vector. The VEE virus partial gene can be substituted with the PED virus spike gene. Recombinant vaccines can be produced by substitution of the target gene in the VEE vector. Both of these new vaccine technologies made it possible to control the infectious disease efficiently in a relatively short time.
Alphavirus ; Animal Diseases ; Animals* ; Circovirus ; Communicable Diseases ; Diarrhea ; Encephalitis Virus, Venezuelan Equine ; Encephalomyelitis, Equine ; Immunity, Cellular ; Porcine epidemic diarrhea virus ; RNA ; Vaccines ; Vaccines, Synthetic ; Vaccines, Virus-Like Particle ; Venezuela

BACKGROUND AND PURPOSE: Acute posterior multifocal placoid pigment epitheliopathy (APMPPE) is an immune-mediated chorioretinal disease that causes acute visual symptoms with characteristic ophthalmoscopic findings. Neurological complications are rarely reported in the literature. Here we report two new cases of APMPPE that presented with neurological manifestations, one of which was associated with peripheral neuropathy, which has not been described before. METHODS: A retrospective database review of all patients with a diagnosis of APMPPE was performed. Clinical, ophthalmological, and neurological data were analyzed, and only cases of APMPPE with neurological complications were included. A literature review of several databases was also performed, and previous case reports were reviewed and analyzed in detail. RESULTS: In total, 56 cases of APMPPE-associated neurological complications were included in the analyses: 54 from the literature and 2 from our own practice. The most common complication was cerebral vasculitis, which affected 28 patients (50%), followed by headaches in 15 patients (26.8%). The other complications include sixth-cranial-nerve palsy, transient hearing loss, meningoencephalitis, cavernous sinus thrombosis, and viral meningitis. CONCLUSIONS: This report adds to the literature of a novel association of APMPPE with peripheral neuropathy, and comprehensively reviews the neurological manifestations of this disease. A high level of suspicion should be applied when dealing with a case of APMPPE. We recommend applying detailed clinical neurological examinations and magnetic resonance imaging to APMPPE patients, and then early steroid treatment if the examination is positive or even suspicious. Early treatment with steroids and long-term treatment with immunosuppressive azathioprine with interval neurological evaluations will contribute positively to the outcomes and avoid fatal complications, namely strokes.
Adrenal Cortex Hormones ; Azathioprine ; Cavernous Sinus Thrombosis ; Diagnosis ; Headache ; Hearing Loss ; Humans ; Magnetic Resonance Imaging ; Meningitis, Viral ; Meningoencephalitis ; Neurologic Examination ; Neurologic Manifestations* ; Paralysis ; Peripheral Nervous System Diseases ; Retrospective Studies ; Steroids ; Stroke ; Vasculitis, Central Nervous System

Analyzing HI tests of 110 cases of clinical Japanese Encephalitis in 1982, the following results are obtained. 1. The results of HI test are positive in 39 (35.5%), borderline positive in 19 (9.1%), negative in 14 (12.7%) and undetermined in 47 (43.7%) cases. 2. In 49 cases of positive HI test, 14 cases reveal the positive result on the first HI test requested in 5-27 days after the clinical onset of symptoms, and 35 cases show increasing HI titers on the follow-up studies. There is a tendency of increasing HI titers upto 3-4 weeks of onset and sustaining the value for more than two months. 3. In 35 cases with increasing titers on follow-up study, the highest titer is 1:80 in 5 cases, and the half of HI negative cases maintain that value throughout the course. 4. There is no significant statistical differences in clinical characteristics, laboratory and cerebrospinal fluid studies between the patient group of HI positive or borderline and group of HI negative or undermined, except mean hospital day and incidence of coma and death.
Cerebrospinal Fluid ; Coma ; Encephalitis, Arbovirus* ; Encephalitis, Japanese ; Follow-Up Studies ; Hemagglutination Inhibition Tests* ; Hemagglutination* ; Humans ; Incidence ; Korea*

OBJECTIVETo develop a rapid, cost effective RT-PCR method for the mass scale diagnosis of such diseases at the viremia stage to find out the actual disease burden in that area.

METHODSFor this purpose, cases with the history of only short febrile illness were considered. Thus 157 samples with the history of dengue/chikungunya like illness and only 58 samples with a history of acute encephalitis syndrome (AES) were selected.

RESULTSOut of 157 samples, 42 and 74 were detected as dengue and chikungunya, respectively and out of 58 AES cases only 23 could be detected as Japanese encephalitis by this RT-PCR method.

CONCLUSIONSThis cost effective RT-PCR method can detect the total positive cases that remain undetected by ELISA method. Moreover, this method is capable to detect the viral RNA from patients' sera even after the appearance of IgM antibody at one fifth costs as compared with the other commercially available kits.

Antibodies, Viral ; blood ; Arbovirus Infections ; diagnosis ; virology ; Arboviruses ; genetics ; Chikungunya Fever ; diagnosis ; virology ; Dengue ; diagnosis ; virology ; Encephalitis Virus, Japanese ; genetics ; Encephalitis, Japanese ; diagnosis ; virology ; Fever ; diagnosis ; virology ; Humans ; Immunoglobulin M ; blood ; Mass Screening ; RNA, Viral ; blood ; Reverse Transcriptase Polymerase Chain Reaction ; economics ; methods ; Sensitivity and Specificity ; Viremia ; diagnosis ; virology