Imaging spectrum of viral encephalitis: A case series (original) (raw)

Usefulness of various MRI sequences in the diagnosis of viral encephalitis

Acta Tropica, 2010

There is paucity of studies regarding the utility of various conventional MRI sequences in the diagnosis of viral encephalitis. The present study evaluates the usefulness of various MRI sequences in acute viral encephalitis. 88 consecutive viral encephalitis patients, aged 2-72 years were subjected to clinical evaluation. Consciousness was assessed by Glasgow Coma Scale (GCS). Serum or cerebrospinal fluid (CSF) was analyzed for dengue, Japanese encephalitis (JE), herpes, measles, echo, coxsackie and polio viruses using ELISA or PCR. Cranial MRI was done and T1, T2, FLAIR and DW images were obtained. The MRI changes were correlated with type of encephalitis and duration of illness. All the patients had altered sensorium and 37 had seizures. 22 patients had JE, 9 had dengue, 8 had herpes simplex encephalitis (HSE), 2 had Epstein-Barr virus encephalitis (EBVE) and 47 had non-specific encephalitis. The median duration of MRI study from onset was 10 days. In JE (20/22), HSE (8/8), and EBVE (2/2), MRI abnormalities were more common compared to dengue (2/9) and non-specific (20/47) encephalitis. The MRI abnormalities were more common in FLAIR (57.1%) compared to T2 (52.9%), DWI (38.1%) and T1 (19.3%) sequences. The mean ADC value in JE patients was lower (974.0 ± 110.85 ×10 −6 mm 2 /s) than HSE (1024.33 ± 485.76 × 10 −6 mm 2 /s). Additional MRI lesions were seen in 12.6% cases on FLAIR sequence. FLAIR and T2 sequences were more sensitive in revealing abnormalities in viral encephalitis.

Viral Encephalitis: Etiology, Clinical Features, Diagnosis and Management

Viral encephalitis is worldwide spread pathology with high morbidity and mortality. Its incidence is higher in children. Enteroviruses, varicella zoster virus and herpes simplex viruses are the most frequent agents. However, in spite of the use of modern microbiological and radiological methods, an etiological diagnosis is reached in less than 50% of cases, making a careful differential diagnosis with non viral brain diseases imperative. Pathogenesis is elusive and therapy continues to remain supportive in almost all cases, as the only virus-directed treatment is available for herpesvirus-related encephalitis and a role for steroids continues to be debated. Novel and more targeted therapies are eagerly needed.

Role of Magnetic Resonance Imaging in Identifying the Different Imaging Patterns of Viral Encephalitis

International Journal of Contemporary Medicine, Surgery and Radiology, 2018

Trauma is a leading cause of mortality in people aged younger than 45 years. Head injury is the number one cause of trauma mortality and it is directly associated with one half of all deaths associated with trauma. Traumatic acute subdural Hematoma is one of the most common traumatic neurosurgical emergencies and often required surgical intervention. This clinical study was done to examine the hospital mortality and analyse the risk factors for mortality in patients treated surgically for isolated traumatic acute subdural Hematoma. Material and methods: Prospective evaluation of 82 operated cases of ASDH was done. Data was collected from case files and operative records. CT scan variables, clinical variables and operative variables were evaluated. Results: overall mortality was 30.49%. Male mortality was 31.25% and female mortality was 27.78%. High mortality with advanced age. No clinically significant difference in mortality due to different mechanism of injury. Other significant mortality indicators were pupillary reaction, midline shift, diffuse edema and hypotension. Conclusion: The overall mortality of 30. 49% was within the predicted range as per recent literature. Age of the patient, pupillary reaction, Hematoma thickness, midline shift and evidence of diffuse brain swelling during surgery were found to be independent predictors of mortality. This findings may allow for more informed decision making in approaching a particular case.

Viral Encephalitis: A Hard Nut to Crack

Annals of the National Academy of Medical Sciences (India)

Viral encephalitis is inflammation of brain that manifests as neurological complication of viral infections. There are quite a good number of viruses, for example, human herpes virus, Japanese encephalitis, and enteroviruses that can result in such a dreadful condition. Geographical location, age, gender, immune status, and climatic conditions also contribute to the establishment of this disease in an individual. Clinical signs and symptoms include fever, headache, altered level of consciousness, changed mental status, body ache, seizures, nausea, and vomiting. Effective management of this disease relies on timely diagnosis that in turn depends on apt and suitable investigation techniques. Traditional investigations have thinned out these days owing to the fact that advanced molecular technologies have been introduced to the diagnostic field. Treatment of viral encephalitis mainly involves symptomatic relieve from fever, malaise, myalgia along with measures to reduce viral load in t...

Viral encephalitis: a clinician's guide

Practical neurology, 2007

The management of patients with suspected viral encephalitis has been revolutionised in recent years with improved imaging and viral diagnostics, better antiviral and immunomodulatory therapies, and enhanced neurointensive care. Despite this, disasters in patient management are sadly not uncommon. While some patients are attacked with all known antimicrobials with little thought to investigation of the cause of their illness, for others there are prolonged and inappropriate delays before treatment is started. Although viral encephalitis is relatively rare, patients with suspected central nervous system (CNS) infections, who might have viral encephalitis, are not. In addition, the increasing number of immunocompromised patients who may have viral CNS infections, plus the spread of encephalitis caused by arthropod-borne viruses, present new challenges to clinicians. This article discusses the Liverpool approach to the investigation and treatment of adults with suspected viral encephal...

Viral encephalitis: a review of diagnostic methods and guidelines for management

European Journal of Neurology, 2005

Viral encephalitis is a medical emergency. The spectrum of brain involvement and the prognosis are dependent mainly on the specific pathogen and the immunological state of the host. Although specific therapy is limited to only several viral agents, correct immediate diagnosis and introduction of symptomatic and specific therapy has a dramatic influence upon survival and reduces the extent of permanent brain injury in survivors. We searched MEDLINE (National Library of Medicine) for relevant literature from 1966 to May 2004. Review articles and book chapters were also included. Recommendations are based on this literature based on our judgment of the relevance of the references to the subject. Recommendations were reached by consensus. Where there was lack of evidence but consensus was clear we have stated our opinion as good practice points. Diagnosis should be based on medical history, examination followed by analysis of cerebrospinal fluid for protein and glucose contents, cellular analysis and identification of the pathogen by polymerase chain reaction (PCR) amplification (recommendation level A) and serology (recommendation level B). Neuroimaging, preferably by magnetic resonance imaging, is an essential aspect of evaluation (recommendation level B). Lumbar puncture can follow neuroimaging when immediately available, but if this cannot be obtained at the shortest span of time it should be delayed only in the presence of strict contraindications. Brain biopsy should be reserved only for unusual and diagnostically difficult cases. All encephalitis cases must be hospitalized with an access to intensive care units. Supportive therapy is an important basis of management. Specific, evidence-based, anti-viral therapy, acyclovir, is available for herpes encephalitis (recommendation level A). Acyclovir might also be effective for varicella-zoster virus encephalitis, gancyclovir and foscarnet for cytomegalovirus encephalitis and pleconaril for enterovirus encephalitis (IV class of evidence). Corticosteroids as an adjunct treatment for acute viral encephalitis are not generally considered to be effective and their use is controversial. Surgical decompression is indicated for impending uncal herniation or increased intracranial pressure refractory to medical management.

The Causes and Long-Term Consequences of Viral Encephalitis

Frontiers in Cellular Neuroscience

Reports regarding brain inflammation, known as encephalitis, have shown an increasing frequency during the past years. Encephalitis is a relevant concern to public health due to its high morbidity and mortality. Infectious or autoimmune diseases are the most common cause of encephalitis. The clinical symptoms of this pathology can vary depending on the brain zone affected, with mild ones such as fever, headache, confusion, and stiff neck, or severe ones, such as seizures, weakness, hallucinations, and coma, among others. Encephalitis can affect individuals of all ages, but it is frequently observed in pediatric and elderly populations, and the most common causes are viral infections. Several viral agents have been described to induce encephalitis, such as arboviruses, rhabdoviruses, enteroviruses, herpesviruses, retroviruses, orthomyxoviruses, orthopneumovirus, and coronaviruses, among others. Once a neurotropic virus reaches the brain parenchyma, the resident cells such as neurons,...

The prognostic role of magnetic resonance imaging and single-photon emission computed tomography in viral encephalitis

Acta Radiologica, 2008

Background: There is a paucity of studies evaluating the prognostic role of magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) changes in viral encephalitis. Purpose: To study MRI and SPECT changes in patients with viral encephalitis, and to correlate these changes with clinical findings and outcome. Material and Methods: During 1997–2006, 31 encephalitis patients (aged 2–60 years; nine females, 22 males) underwent both MRI and SPECT studies. Their demographic and clinical data and 6-month outcome were recorded. For the diagnosis of encephalitis, polymerase chain reaction (PCR) and IgM enzyme-linked immunosorbent assay (ELISA) were carried out. Cranial MRI was done on a 1.5T scanner, and 99mTc ethylene cysteine dimer (ECD) SPECT using a gamma camera. Outcome was defined at 6 months as complete, partial, or poor recovery. Results: 19 patients had Japanese encephalitis (JE), one had herpes simplex encephalitis (HSE), and 11 had nonspecific encephal...

Aetiology of viral central nervous system infection, a Malaysian study

Neurology Asia, 2008

Over 100 viruses are known to cause acute viral encephalitis in human. In order to diagnose a viral central nervous system infection, various laboratory diagnosis methods have been used. In this study, we examined 220 cerebrospinal fluid samples that were received at the Diagnostic Virology Laboratory of University Malaya Medical Centre between year 2004 to 2006, by viral isolation, pathogen specific antibody ELISA, polymerase chain reaction (PCR) and Real-Time PCR. Majority of the samples were from patients <10 years old. Out of 220 samples, 3 were positive for viral isolation, 27 for PCR (inclusive for the 3 positive for viral isolation) and 39 for pathogen specific ELISA. The total positive detection rate of this study was 30%. Herpes virus was the most important aetiologic agent, responsible for 58% of infection, followed by paramyxovirus (especially measles virus) in 26% of infection, and 14% by enterovirus. Parvovirus and flavivirus were the other common viruses. Among the herpes viruses, herpes simplex and cytomegalovirus were the most common.

Epidemiological Profile of Acute Viral Encephalitis

Indian journal of pediatrics, 2017

To study the etiology and clinico-epidemiological profile of acute viral encephalitis in children with acute encephalitis syndrome (AES). An observational study including 100 patients fulfilling the criteria for AES was conducted in children of age group 1 mo - 16 y. Viral isolation was done on RD cells, HEp-2 cells and Vero cells from the cerebrospinal fluid samples of suspected viral encephalitis (VE) cases. An enzyme immunoassay for IgM antibodies was performed for measles, mumps, Varicella zoster virus (VZV), Herpes simplex virus 1 (HSV1) and Japanese encephalitis virus (JEV). Multiplex polymerase chain reaction (PCR) was done for Cytomegalovirus, Epstein Barr virus (EBV), HSV1 & 2, VZV, Enterovirus, Parecho virus, Human Herpes virus (HHV 6, 7) and Parvovirus B19. A micro neutralization test was performed for Enterovirus 71. Out of enrolled 100 patients, 73 were of probable viral encephalitis. HSV1 (31.50%) was the commonest virus followed by Adenovirus (10.95%), Parvovirus (2.7...