acyclovir and Seizures

Herpes simplex virus (HSV) is a common cause of viral encephalitis and can result in refractory seizures. Although HSV encephalitis (HSVE) is treated primarily with acyclovir, surgery can play a role in medically intractable cases.. To systematically review cases describing surgery for the treatment of severe HSVE. We also present an illustrative case of anterior temporal lobectomy (ATL) for refractory status epilepticus in a patient with unilateral HSVE. This case demonstrates one clinical context in which surgery can be a useful adjunct.. We performed a systematic review using PubMed and Google Scholar, including case reports and series describing surgical interventions for HSVE. Clinical data were extracted from 54 publications that incorporated 67 patient cases.. Surgical decompression occurred at a wide range of times after the onset of illness, although most patients were operated on 4 or more days after HSVE symptoms began. Numerous reports indicated that decompressive craniectomy, temporal lobectomy, and hematoma removal could treat intractably elevated intracranial pressure because of HSVE with favorable long-term outcomes. We describe an additional case in which a 52-year-old woman with HSVE developed refractory right temporal lobe seizures. After ATL, the seizures resolved with significant clinical improvement.. Surgical treatment can be a useful adjunct for treatment of HSVE. There is substantial variability in the timing of surgical decompression in patients with HSVE, which can be necessary up to approximately 3 weeks after illness onset. ATL should be considered for refractory status epilepticus in HSVE with a unilateral seizure focus.

Topics: Acyclovir; Anterior Temporal Lobectomy; Encephalitis, Herpes Simplex; Female; Humans; Middle Aged; Seizures; Status Epilepticus

Viral encephalitis causes an altered level of consciousness, which may be associated with fever, seizures, focal deficits, CSF pleocytosis, and abnormal neuroimaging. Potential pathogens include HSV, VZV, enterovirus, and in some regions, arboviruses. Autoimmune (eg, anti-NMDA receptor) and paraneoplastic encephalitis are responsible for some cases where no pathogen is identified. Indications for ICU admission include coma, status epilepticus and respiratory failure. Timely initiation of anti-viral therapy is crucial while relevant molecular and serological test results are being performed. Supportive care should be directed at the prevention and treatment of cerebral edema and other physiological derangements which may contribute to secondary neurological injury.

Topics: Acyclovir; Adrenal Cortex Hormones; Anticonvulsants; Antiviral Agents; Brain Diseases; Brain Edema; Consciousness Disorders; Encephalitis; Encephalitis, Viral; Encephalomyelitis, Acute Disseminated; Glasgow Coma Scale; Guillain-Barre Syndrome; Hashimoto Disease; Humans; Intensive Care Units; Paraneoplastic Syndromes, Nervous System; Seizures; Status Epilepticus; Viremia

Topics: Acyclovir; Aphasia; Brain; Encephalitis, Viral; Fever; Herpes Simplex; Humans; Infant; Male; Seizures; Simplexvirus; Tomography, X-Ray Computed; Treatment Outcome; Vomiting

The patient with meningoencephalitis should be evaluated carefully for the presence of focal signs referable to involvement of the frontotemporal regions of the brain. A significant percentage of cases of encephalitis with discrete focal features are caused by infection with herpes simplex virus. If focal signs are not present, the patient should be managed conservatively but examined regularly because focal neurologic dysfunction may present at any time in the course of disease. If there is clinical and electrographic evidence of involvement of the frontotemporal lobes, radiographic imaging is indicated as well as studies of the serum and cerebrospinal fluid for antibodies indicative of a recent infection with herpes simplex virus. Assuming that the radiographic scans identify the characteristic changes of a focal encephalitis and that the antibody responses are indicative of a recent herpes simplex virus infection, brain biopsy should be done in order to confirm the diagnosis. With positive evidence for HSE, treatment with ara-A should be initiated and continued for 10 days. If the biopsy proves negative for virus, ara-A should be discontinued and the patient managed conservatively (Fig. 3). Although the NIAID study of ara-A treatment of HSE is encouraging, the numbers are small and the evidence is, at best, only suggestive. It is reasonable to use this drug until a better one becomes available for the treatment of known HSE, and treatment should be instituted early before cellular injury is extensive. In centers familiar with this problem, biopsy confirmation of the diagnosis is a simple and informative procedure and can be defended. If patients cannot be moved to a center of this type, physicians familiar with the many facets of this problem should be consulted, and a decision regarding biopsy and treatment should be individualized in light of the circumstances. Biopsy should only be undertaken when the procedure can be done with minimal risk to the patient and the assurance that the maximum amount of information can be gained.

Topics: Acyclovir; Antibodies, Viral; Biopsy; Combined Modality Therapy; Electroencephalography; Encephalitis; Herpes Simplex; Humans; Pseudotumor Cerebri; Seizures; Simplexvirus; Tomography, Emission-Computed; Tomography, X-Ray Computed; Vidarabine; Vidarabine Phosphate

Topics: Acyclovir; Clinical Trials as Topic; Encephalitis; Female; Herpes Simplex; Humans; Seizures; Vidarabine

Aciclovir-induced neurotoxicity results from the accumulation of aciclovir and its metabolite 9-carboxymethoxymethylguanine (CMMG). It occurs predominantly in older patients with impaired renal function and is characterised by a combination of confusion and psychiatric changes. Seizures, myoclonus and dysarthria may also occur. Critically, peritoneal dialysis has little effect on reversing the toxic effects of aciclovir. We describe a woman in her 70s with renal failure who developed confusion and seizures after receiving aciclovir. She was ultimately diagnosed with aciclovir-induced neurotoxicity, confirmed by an elevated serum CMMG concentration. This condition is likely to be underdiagnosed and the neurologist's primary challenge is differentiating aciclovir-induced neurotoxicity from viral encephalitis.

Topics: Acyclovir; Aged; Antiviral Agents; Confusion; Encephalitis, Viral; Female; Humans; Neurotoxicity Syndromes; Seizures

Herpes simplex encephalitis is the most common cause of sporadic viral encephalitis worldwide but presents as a diagnostic challenge at many settings due to its non-specific symptoms, which can be easily mistaken for systemic infection or metabolic encephalopathy. It has diverse range of presentations from fever, altered sensorium, nausea, vomiting, meningismus to seizures, neurological deficits and coma in advanced stages. It is associated with significant morbidity and mortality if treatment is delayed or inadequate. We here discuss a case of Herpes simplex virus (HSV) encephalitis which rapidly progressed to result in irreversible neurological insult due to delayed diagnosis and treatment.

Topics: Acyclovir; Administration, Intravenous; Antiviral Agents; Encephalitis, Herpes Simplex; Humans; Seizures

To identify the prevalence of herpes simplex encephalitis (HSE), factors influencing the duration of empirical acyclovir and frequency of acute kidney injury (AKI) in children with acute encephalitis syndrome (AES).. Prospective observational study.. Pediatric Emergency Department and PICU of a tertiary hospital in Northern India.. All consecutive, eligible children between 1 month and 12 years old presenting with AES, defined as altered consciousness for greater than 24 hours (including lethargy, irritability, or a change in personality) and two or more of the following signs: 1) fever (temperature ≥ 38°C) during the current illness, 2) seizures or focal neurological signs, 3) cerebrospinal fluid (CSF) pleocytosis, 4) electroencephalogram, and/or 5) neuroimaging suggesting encephalitis, who received at least one dose of acyclovir.. None.. Of the 101 children screened, 83 were enrolled. The median (interquartile range [IQR]) age was 3 years (1-6 yr). Thirty-one children (37.3%) were diagnosed with AES, of which four were labeled as probable HSE (three based on MRI brain, one based on serology). Scrub typhus, dengue, Japanese encephalitis, and mumps were the other infective causes. The median (IQR) duration of acyclovir therapy was 72 hours (24-264 hr); 21 children (25.3%) received acyclovir for less than 24 hours and 11 (13.3%) for greater than or equal to 14 days. New-onset AKI was seen in 18 children (21.7%) but was mostly transient. Death ( n = 8, 9.6%) and discontinuation of care due to futility or other reasons ( n = 15, 18%) were noted in 23 children (28%). Factors associated with duration of acyclovir greater than 7 days, on univariable analysis, were lower modified Glasgow Coma Score at admission, requirement of invasive ventilation, invasive intracranial pressure monitoring, and CSF pleocytosis (5-500 cells). On multivariable analysis, only CSF pleocytosis of 5-500 cells was associated with duration of acyclovir greater than 7 days.. Given the low prevalence of HSE, and the risk of AKI, this study sensitizes the need to review our practice on initiation and stopping of empirical acyclovir in children with acute encephalitis.

Topics: Acyclovir; Antiviral Agents; Child; Child, Preschool; Encephalitis, Herpes Simplex; Humans; Leukocytosis; Seizures

The article gives the clinical case of herpes simplex encephalitis relapse with the resistant seizures in a child. What we describe is a clinical approach towards the differential diagnostic of the seizures in structural epilepsy, which are resistant to anticonvulsants, or late herpes simplex encephalitis relapse. Good clinical perspective may be the indication of the intratecal synthesis of the IgG-specific antibodies to the herpes simplex type 1 and 2. Conducting etiotropic treatment with the appointment of acyclovir and pathogenetic therapy with the use of Cytoflavin contributed to the rapid and stable remission of epileptic seizures and regression of neurological deficit.. В статье представлено клиническое описание рецидива герпетического энцефалита (ГЭ) у ребенка, осложненного резистентными судорогами. Представлена тактика дифференциальной диагностики судорожного синдрома как проявления структурной эпилепсии, резистентной к противоэпилептической терапии, и позднего рецидива ГЭ. Диагностически ценным может быть обнаружение интратекального синтеза специфических IgG к вирусу простого герпеса 1-го и 2-го типов, что в представленном случае позволило подтвердить реактивацию герпетической инфекции в центральной нервной системе и явилось основанием для повторного курса специфической терапии. Проведение этиотропного лечения с назначением ацикловира и патогенетической терапии с применением Цитофлавина способствовало быстрой и стойкой ремиссии эпилептических приступов и регрессу неврологического дефицита.

Topics: Acyclovir; Child; Encephalitis, Herpes Simplex; Epilepsy; Herpes Simplex; Humans; Immunoglobulin G; Recurrence; Seizures

In recent years, there have been an increasing number of reports on overlapping antibodies in autoimmune encephalitis (AE). There are various types of overlapping antibodies, but the clinical significance of each type is not yet clear. Glial antibodies, such as MOG, AQP4, and especially NMDAR, can be detected in patients with AE. However, little is known about the overlapping antibodies of anti-glial fibrillary acidic protein (GFAP), and only a few case reports have described this overlap. Case presentation The patient was a 7-year-old girl with recurrent intermittent fever and seizures, and viral encephalitis was diagnosed at the beginning of the disease. She was discharged after treatment with acyclovir, high-dose immunoglobulins, and valproic acid as an antiseizure medication. Subsequently, the patient still had occasional seizures and abnormal behavior, and the anti-NMDAR antibody test was positive (1:3.2). She was treated with high-dose methylprednisolone and antiseizure therapy. Approximately half a year later, the patient experienced fever and seizures again, serum GFAP IgG was 1:100, and a head MRI indicated new lesions. Improvement was achieved after repeated high-dose methylprednisolone and continuous prednisone anti-inflammatory therapy.. Anti-NMDAR encephalitis combined with GFAP-IgG is uncommon, and repeated tests for AE-associated antibodies may be required in patients with recurrent encephalitis. Compared with cerebrospinal fluid antibody-positive children, serum GFAP IgG-positive children should be comprehensively diagnosed according to their clinical manifestations. It is worth considering whether overlapping antibody syndrome can still be an issue for patients with AE who recover and have negative antibodies after a few months if disease recurrence and new antibodies are detected.

Topics: Acyclovir; Anti-Inflammatory Agents; Anti-N-Methyl-D-Aspartate Receptor Encephalitis; Autoantibodies; Child; Encephalitis; Female; Hashimoto Disease; Humans; Immunoglobulin G; Methylprednisolone; Neoplasm Recurrence, Local; Prednisone; Seizures; Syndrome; Valproic Acid

To describe a term newborn with acquired severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and multisystem involvement including seizures associated to ischemic lesions in the brain.. Coronavirus disease 2019 (COVID-19) is predominantly a respiratory infection, but it may affect many other systems. Most pediatric COVID-19 cases range from asymptomatic to mild-moderate disease. There are no specific clinical signs described for neonatal COVID-19 infections. In children, severe central nervous system compromise has been rarely reported.. We describe a 17-day-old newborn who acquired a SARS-CoV-2 infection in a family meeting that was admitted for fever, seizures and lethargy and in whom consumption coagulopathy, ischemic lesions in the brain and cardiac involvement were documented.. SARS-CoV-2 neonatal infection can be associated with multi-organic involvement. In our patient, significant central nervous system compromise associated to ischemic lesions and laboratory findings of consumption coagulopathy were found.. Although neonatal SARS-CoV-2 infections are infrequent, they can be associated with multi-organic involvement. Neonatologists and pediatricians should be aware of this unusual way of presentation of COVID-19 in newborn infants.

Topics: Acyclovir; Anti-Bacterial Agents; Antiviral Agents; Brain; Brain Ischemia; Ceftriaxone; COVID-19; COVID-19 Drug Treatment; Fever; Frontal Lobe; Humans; Infant, Newborn; Infant, Newborn, Diseases; Lethargy; Magnetic Resonance Imaging; Male; Nasopharynx; SARS-CoV-2; Seizures

Topics: Acyclovir; Anti-Bacterial Agents; Antiviral Agents; Ceftriaxone; Diagnosis, Differential; Encephalomyelitis, Eastern Equine; Fever; Humans; Infant; Male; Nervous System Diseases; Seizures

Topics: Acyclovir; Anaphylaxis; Basal Ganglia; Brain; Child; Dexamethasone; Drug Hypersensitivity; Drug Tolerance; Female; Humans; Hypersensitivity; Immunoglobulin E; Seizures; Skin Tests

Bilateral independent periodic lateralised epileptiform discharges (BIPLEDs) in electroencephalograms (EEGs) are commonly caused by anoxic encephalopathy and central nervous system infections. They are associated with coma and high mortality and are thus markers of poor prognosis. We present a case of encephalitis who presented with BIPLEDs in EEG. Though the clinical, EEG and MRI features closely resembled herpes simplex encephalitis, further investigations proved it to be Epstein-Barr virus (EBV) encephalitis. Despite the presence of BIPLEDs in the EEG, the patient had a rapid clinical response to therapy with acyclovir. We emphasise that BIPLEDs may not always indicate poor prognosis especially in the setting of EBV encephalitis.

Topics: Acyclovir; Adult; Antiviral Agents; Diagnosis, Differential; Electroencephalography; Encephalitis, Viral; Herpesvirus 4, Human; Humans; Magnetic Resonance Imaging; Male; Seizures

A 75-year-old woman presented with new onset of confusion, intense episodic dizziness and formed visual hallucinations. Herpes simplex encephalitis and non-convulsive temporal lobe seizures were confirmed with cerebrospinal fluid (CSF) and electroencephalography testing. In addition, her hospital course was complicated by syndrome of inappropriate antidiuretic hormone secretion and atonic bladder contributing to an episode of urinary tract infection. After completing 3 weeks of acyclovir treatment, the patient became obtunded with right arm choreiform movements and persistent inflammatory CSF findings not attributable to persistent herpes simplex virus infection or other confounding factors. The patient responded to steroid treatment. Repeated autoimmune and paraneoplastic evaluations were negative. Both clinical (cognitive testing and atonic bladder) and CSF inflammatory finding improved in the follow-up period.

Topics: Acyclovir; Aged; Antiviral Agents; Chorea; Electroencephalography; Encephalitis; Encephalitis, Herpes Simplex; Female; Glucocorticoids; Humans; Inappropriate ADH Syndrome; Methylprednisolone; Seizures; Urinary Bladder, Underactive; Urinary Retention; Urinary Tract Infections

Parvovirus B19 (PVB19) has rarely been identified as a cause of encephalitis in immunocompetent adults, in whom clinical information regarding PVB19 encephalitis has remained unclear. Herein, we report the clinical presentations, laboratory and imaging findings, and treatment outcomes of five immunocompetent adults with PVB19 encephalitis. Although none of the patients showed any distinctive features of PVB19 infection, they showed various clinical manifestations, including one instance of brainstem involvement. Additionally, immunotherapy can be considered an effective approach, especially in immunocompetent adults with PVB19 encephalitis who are resistant to the initial management.

Topics: Acyclovir; Adult; Antiviral Agents; Drug Administration Schedule; Encephalitis; Female; Humans; Immunocompetence; Immunoglobulins, Intravenous; Magnetic Resonance Imaging; Male; Methylprednisolone; Middle Aged; Parvoviridae Infections; Parvovirus B19, Human; Seizures; Treatment Outcome; Viral Load

Topics: Acyclovir; Antineoplastic Agents, Alkylating; Antiviral Agents; Brain Stem Neoplasms; Cognitive Dysfunction; Cranial Irradiation; Dacarbazine; Delirium; Dexamethasone; Diagnosis, Differential; Encephalitis, Herpes Simplex; Female; Glioma; Herpesvirus 1, Human; Humans; Leukocytosis; Magnetic Resonance Imaging; Seizures; Temozolomide; Young Adult

Topics: Acyclovir; Adult; Anticonvulsants; Antiviral Agents; Brain; Brain Edema; Confusion; Diuretics, Osmotic; DNA, Viral; Encephalitis, Herpes Simplex; Fever; Herpesvirus 1, Human; Humans; Male; Mannitol; Polymerase Chain Reaction; Seizures; Temporal Lobe; Tomography, X-Ray Computed

We report a case of a 62-year-old female with seizures and encephalitis. Molecular testing of the patient's cerebrospinal fluid was positive for both herpes simplex virus 1 and 2 (HSV-1 and HSV-2). To our knowledge, this is the first report of simultaneous detection of HSV-1 and HSV-2 in cerebrospinal fluid.

Topics: Acyclovir; Antiviral Agents; DNA, Viral; Encephalitis; Female; Herpes Simplex; Herpesvirus 1, Human; Herpesvirus 2, Human; Humans; Middle Aged; Seizures

Viral encephalitis are rare and potentially serious conditions with different etiologist, and not always identifiable. Our aim is to describe the etiological, clinical presentation and neurological outcome of viral encephalitis admitted in Paediatrics Intensive Care Units (PICUs) in Spain.. Observational prospective multicenter study. Children with viral encephalitis admitted to 14 PICUs, for a period of 3 years (2010-2013) were included. Polymerase chain reaction for the etiological diagnosis and neurotropic virus serology in blood and cerebrospinal fluid were used. Personal history, clinical presentation, evolution and neurological status at discharge were recorded.. 80 patients were included with a mean age of 5 years, 70% male. The most relevant clinical symptoms were decreased consciousness (86%), fever (82.4%), seizures (67%), vomiting (42%), headache (27%), agitation (25%) and dis-orientation (23%). The etiologic diagnosis was established in 35%, being more frequent herpes simplex virus and enterovirus. The outcome was discharge without sequelae in 55 patients (69%), mild to moderate sequelae in 19 (23.5%) and severe in 6 (7.5%). Two patients died.. In the Spanish PICU etiological diagnosis was established only in a third of cases of children with suspected acute viral encephalitis. Despite the clinical severity we observed a low mortality and morbidity rate. At discharge from the PICU, most children had no neurological sequelae or were mild.. Etiologia, presentacion clinica y evolucion neurologica de las encefalitis viricas graves en la edad pediatrica (estudio ECOVE).. Introduccion. Las encefalitis viricas son procesos raros y potencialmente graves, con etiologia diversa y no siempre identificable. El objetivo es describir las caracteristicas etiologicas, la presentacion clinica y la evolucion neurologica de las encefalitis viricas que ingresaron en las unidades de cuidados intensivos pediatricos (UCIP) en España. Pacientes y metodos. Estudio prospectivo multicentrico observacional. Se incluyeron los niños ingresados en 14 UCIP con diagnostico de encefalitis virica durante un periodo de tres años (2010-2013). Para el diagnostico etiologico se utilizo reaccion en cadena de la polimerasa y serologia a virus neurotropos en la sangre y el liquido cefalorraquideo. Se registraron los antecedentes personales, la presentacion clinica, la evolucion y la situacion neurologica en el momento del alta. Resultados. Se incluyeron 80 pacientes con edad media de 5 años; el 70%, varones. Los sintomas clinicos mas relevantes fueron disminucion de conciencia (86%), fiebre (82,4%), convulsiones (67%), vomitos (42%), cefalea (27%), agitacion (25%) y desorientacion (23%). Se llego al diagnostico etiologico en un 35%, y los mas frecuentes fueron virus herpes simple y enterovirus. La evolucion fue curacion sin secuelas en 55 pacientes (69%, sobre todo enterovirus, rotavirus y virus respiratorios), secuelas leves-moderadas en 19 (23,5%) y graves en seis (7,5%). Dos pacientes fallecieron. Conclusiones. En las UCIP españolas solo se realizo el diagnostico etiologico en un tercio de los niños con sospecha de encefalitis virica grave. A pesar de la gravedad clinica, hemos observado una tasa de mortalidad y morbilidad baja. La amplia mayoria son dados de alta de la UCIP con ninguna o escasa secuela neurologica.

Topics: Acute Disease; Acyclovir; Adolescent; Antiviral Agents; Brain Damage, Chronic; Child; Child, Preschool; Clarithromycin; Consciousness Disorders; Encephalitis, Viral; Female; Fever; Headache; Humans; Infant; Male; Prospective Studies; Seasons; Seizures; Serologic Tests; Spain; Treatment Outcome; Vomiting

N-methyl-D-aspartate receptor antibodies (NMDAR-Abs) can contribute to neurological relapse after herpes simplex virus encephalitis (HSE). We describe a child with NMDAR-Ab encephalitis after HSE, which was recognized and treated early. We discuss the case in the context of existing reports, and we propose a modified immunotherapy strategy to minimize risk of viral reactivation.

Topics: Acyclovir; Anti-N-Methyl-D-Aspartate Receptor Encephalitis; Antiviral Agents; Autoantibodies; Clonidine; Diazepam; Encephalitis, Herpes Simplex; Encephalomalacia; Female; Fever; Humans; Immunocompromised Host; Immunosuppression Therapy; Infant; Leukoencephalopathies; Movement Disorders; Neurological Rehabilitation; Pakistan; Paresis; Phenobarbital; Phenytoin; Plasmapheresis; Receptors, N-Methyl-D-Aspartate; Seizures; Trihexyphenidyl; United Kingdom; Valproic Acid

Acute disseminated encephalomyelitis (ADE) is an inflammatory disorder of the central nervous system that is mediated immunologically and of unknown pathogenesis. It can present at any age, but is much more frequent in children. ADE has no specific biological marker and diagnosis is based on findings from clinical and neuroimaging studies.. To enhance our knowledge of the clinico-radiological profile of this disease.. This retrospective study involved patients under 14 years of age who were admitted to a tertiary hospital over the last 15 years with a diagnosis of ADE. History, clinical presenting symptoms, lab findings from blood/cerebrospinal fluid analyses and radiological semiology were reviewed. In 16 cases an average follow-up of 25 months was performed.. The study examined 20 patients, 70% children, with a mean age of 4.4 years. Forty per cent had a previous febrile episode. Eighty-five per cent presented fever or vomiting, and 70% had altered states of mind. Motor deficits (45%), convulsions (35%) and involvement of the cranial nerves (30%) were predominant. Three children progressed with relapses and three others were left with motor sequelae. Magnetic resonance imaging showed hyperintense lesions in T2, with a pattern of scarce/no enhancement, which were predominantly located in the thalamus (70%), the spinal cord (67%) and the white matter of the sub-cortex (50%). Haemorrhagic ADE was diagnosed in two patients.. ADE is a condition with an important degree of general involvement and neurological repercussions, as well as considerable potential to leave the patient with sequelae. Clinico-analytical data and magnetic resonance scans of the head and spinal cord are relevant for the initial diagnosis and follow-up of patients with ADE.. Perfil clinicorradiologico de la encefalomielitis aguda diseminada en la poblacion infantil. Analisis retrospectivo de una serie de 20 pacientes de un hospital terciario.. Introduccion. La encefalomielitis aguda diseminada (EAD) es un trastorno inflamatorio del sistema nervioso central mediado inmunologicamente y de patogenia desconocida. Puede presentarse en cualquier edad, pero es mucho mas frecuente en niños. La EAD no tiene marcador biologico especifico y el diagnostico se basa en hallazgos clinicos y neurorradiologicos. Objetivo. Mejorar el conocimiento del perfil clinicorradiologico de esta enfermedad. Pacientes y metodos. Estudio retrospectivo con inclusion de pacientes menores de 14 años ingresados en un hospital terciario en los ultimos 15 años con el diagnostico de EAD. Se revisaron antecedentes, signos clinicos de presentacion, datos analiticos en sangre/liquido cefalorraquideo y la semiologia radiologica. En 16 casos se realizo un seguimiento medio de 25 meses. Resultados. Se revisaron 20 pacientes, un 70% niños, con una edad media de 4,4 años. El 40% tuvo un episodio febril previo. El 85% presento fiebre o vomitos, y el 70%, afectacion del estado de consciencia. Predominaron los deficits motores (45%), las convulsiones (35%) y la afectacion de pares craneales (30%). Tres niños presentaron una evolucion recidivante, y otros tres, secuelas motoras. Los estudios de resonancia magnetica mostraron lesiones hiperintensas en secuencias T2, con patron de realce escaso o nulo, que predominaron en los talamos (70%), la medula (67%) y la sustancia blanca subcortical (50%). En dos pacientes se diagnostico EAD hemorragica. Conclusiones. La EAD representa una entidad con importante afectacion general y repercusion neurologica, que muestra un potencial secuelar considerable. Los datos clinicoanaliticos y la resonancia magnetica cerebral y medular son relevantes para el diagnostico inicial y seguimiento de pacientes con EAD.

Topics: Acyclovir; Adolescent; Adrenal Cortex Hormones; Brain; Cerebrospinal Fluid Proteins; Child; Child, Preschool; Comorbidity; Consciousness Disorders; Cranial Nerve Diseases; Diagnosis, Differential; Encephalomyelitis, Acute Disseminated; Female; Humans; Immunoglobulins, Intravenous; Infant; Magnetic Resonance Imaging; Male; Meningitis, Viral; Plasmapheresis; Retrospective Studies; Seizures; Spain; Symptom Assessment; Tertiary Care Centers

We reviewed the characteristics of infants <3 months of age with central nervous system herpes simplex virus infection at our institution. Twenty-six cases were identified. The age range was 4-73 days. Most infants presented with fever, seizure activity and skin lesions. The blood herpes simplex virus polymerase chain reaction was positive in 91% of patients tested. Suppressive oral acyclovir therapy was likely helpful in preventing disease recurrence.

Topics: Acyclovir; Antiviral Agents; Cerebrospinal Fluid; Fever; Herpes Simplex; Humans; Infant; Infant, Newborn; Magnetic Resonance Imaging; Meningoencephalitis; Retrospective Studies; Seizures; Skin Diseases, Viral

Topics: Acyclovir; Antiviral Agents; Brain; Diagnosis, Differential; Electroencephalography; Encephalitis, Viral; Humans; Liver Abscess, Pyogenic; Magnetic Resonance Imaging; Male; Middle Aged; Seizures

Topics: Acyclovir; Aged; Amnesia; Aphasia; Blindness; Diagnosis, Differential; Humans; Male; Seizures; Treatment Outcome

We describe the case of a 19-year-old male diagnosed with Reye syndrome within the context of viral pericarditis and salicylate ingestion. He presented a fatal brain oedema without liver failure. Brain biopsies obtained during a decompressive craniectomy led to the diagnosis.

Topics: Acyclovir; Anti-Inflammatory Agents, Non-Steroidal; Antiviral Agents; Aspirin; Brain Edema; Coma; Decompressive Craniectomy; Fatal Outcome; Glasgow Coma Scale; Humans; Magnetic Resonance Imaging; Male; Pericarditis; Resuscitation; Reye Syndrome; Seizures; Virus Diseases; Young Adult

We present a patient with polymorphic ventricular tachycardia and subsequent ventricular fibrillation with acquired long QT syndrome secondary to herpes encephalitis.

Topics: Acute Disease; Acyclovir; Antiviral Agents; Defibrillators, Implantable; Electrocardiography; Encephalitis, Herpes Simplex; Female; Foscarnet; Ganciclovir; Headache; Heart Arrest; Herpesvirus 2, Human; Humans; Long QT Syndrome; Magnetic Resonance Imaging; Meningitis, Viral; Middle Aged; Seizures; Tachycardia, Ventricular; Torsades de Pointes

The use of herbal and complementary medicine is common. Many herbal products are known to produce serious adverse effects. Borage oil is derived from the seeds of the borage plant (Borago officinalis) an abundant source of gamma-linolenic acid (GLA), and Borage oil has been promoted as a treatment for rheumatoid arthritis, atopic dermatitis, diabetic neuropathy, and menopause-related symptoms. We report a case of status epilepticus in a patient who consumed borage oil for one week.

Topics: Acyclovir; Adult; Anticonvulsants; Borago; Diethylcarbamazine; Drug Therapy, Combination; Female; gamma-Linolenic Acid; Humans; Lorazepam; Pentobarbital; Phenytoin; Plant Oils; Seizures; Status Epilepticus; Treatment Outcome

Herpesviruses can cause an acute, subacute, or chronic disease state in both immunocompetent and immunocompromised individuals. Herpes simplex virus (HSV) encephalitis is most often an acute monophasic disease process. Rarely, however, it may progress to a chronic state, and more rarely still to a granulomatous encephalitis. Prior studies have suggested that antiviral immunity with Toll-like receptors determines susceptibility to herpesviruses. The authors report the case of a 14-year-old girl with a remote history of treated HSV encephalitis, who had intractable seizures and worsening MR imaging changes that were concerning for either a neoplastic or an inflammatory process. She was found to have granulomatous herpes simplex encephalitis and had a low cytokine response to Toll-like receptor 3 stimulation.

Topics: Acyclovir; Adolescent; Antiviral Agents; Brain Neoplasms; Contrast Media; Cytokines; Demyelinating Autoimmune Diseases, CNS; Diagnosis, Differential; Encephalitis, Herpes Simplex; Female; Granuloma; Humans; Magnetic Resonance Imaging; Seizures; Toll-Like Receptor 3; Treatment Outcome

A pregnant 25-year-old woman at 32 weeks' gestation was admitted to an emergency unit after her husband had found her drowsy and with her tongue bitten. The day before admission, the patient had developed a fever of 39 degrees C, was suffering from headaches, was nauseated and had vomited. On admission, she had anterograde and retrograde amnesia, but no somatic neurological deficits were detected.. Routine laboratory testing, lumbar puncture, cerebrospinal fluid analysis, routine bacteriology, brain MRI, and polymerase chain reaction testing for neurotropic viruses including herpes simplex virus types 1 and 2.. Maternal herpes simplex virus type 1 encephalitis.. Antiviral and anticonvulsive therapy, supportive treatment, and cesarean section.

Topics: Acyclovir; Adult; Anticonvulsants; Antiviral Agents; Brain; Encephalitis, Herpes Simplex; Female; Herpesvirus 1, Human; Humans; Lamotrigine; Magnetic Resonance Imaging; Pregnancy; Pregnancy Complications, Infectious; Seizures; Triazines

Herpes simplex encephalitis (HSE) is the most frequent cause of sporadic necrotizing encephalitis in adults. The aim of this study is to describe the characteristics of HSE and the factors influencing its outcome.. Retrospective study of patients diagnosed with HSE in a tertiary care teaching hospital over a 15-year period. Diagnosis was based on a consistent clinical profile for HSE, plus either a PCR-positive CSF HSV study or consistent brain neuroimaging findings. Patients were divided into 2 groups according to the modified Rankin Scale: good outcome (Grades <=2) and poor outcome (Grades >=3).. Thirty-five patients were included. Mean age was 53.9 years. More than half presented febricula or fever, headache, disorientation, behavioral changes, decreased level of consciousness, or neurological deficit. CSF glucose concentration was normal in all patients and WBC count was normal in 8 (23%). PCR for HSV was positive in 92% and cranial MRI was suggestive of HSE in 100% of patients. Mortality was 8.6%. In relation to outcome, age (OR=1.079; 95% CI, 1.023-1.138) and serum albumin level at admission (OR=0.87; 95% CI, 0.794-0.954) were independent prognostic factors at discharge. At 6 months, days of fever after initiation of acyclovir therapy (OR=1.219; 95% CI, 1.046-1.422) and serum albumin level at admission (OR=0.917; 95% CI, 0.87-0.967) were independent prognostic factors.. Normal brain MRI or detection of low CSF glucose concentration requires consideration of diagnoses other than HSE. Age, serum albumin level at admission, and days of fever after initiation of acyclovir therapy were independent prognostic factors of the disease.

Topics: Acyclovir; Adult; Aged; Antiviral Agents; Brain Damage, Chronic; Cerebrospinal Fluid; Dexamethasone; Diagnostic Imaging; Encephalitis, Herpes Simplex; Female; Hospital Mortality; Hospitals, University; Humans; Intracranial Hypertension; Male; Middle Aged; Prognosis; Retrospective Studies; Seizures; Spain

Although herpes simplex virus type 1 (HSV-1) is the most common cause of sporadic encephalitis in immunocompetent adults, it is an unusual cause of encephalitis in patients with HIV/AIDS. We report the case of a 56-year-old man with recently diagnosed HIV infection who presented with subacute mental status changes, fever, and temporal lobe abnormalities evident on brain imaging. Results of a polymerase chain reaction assay of the cerebrospinal fluid were positive for HSV-1. His course was complicated by 2 episodes of cerebral hemorrhage. He ultimately improved after surgical decompression, treatment with acyclovir, and a switch from a protease inhibitor-based antiretroviral regimen to one including an integrase inhibitor.

Topics: Acyclovir; Antiviral Agents; Cerebral Hemorrhage; Encephalitis, Herpes Simplex; Herpesvirus 1, Human; HIV Infections; Humans; Infusions, Intravenous; Male; Memory Disorders; Middle Aged; Seizures; Tomography, X-Ray Computed

To assess the etiology, prognosis, and appropriate treatment of hemophagocytic lymphohistiocytosis (HLH) in neonates.. We collected information on neonates in whom HLH was diagnosed between 1997 and 2007 from participating members of the Japanese Society of Pediatric Hematology.. HLH was diagnosed in 20 patients within 4 weeks after birth. Of the diagnostic criteria for HLH-2004, the incidence of fever was quite low in preterm infants, and hypertriglyceridemia and neutropenia were uncommon. Familial HLH (n = 6) or severe combined immunodeficiency-associated HLH (n = 1) was diagnosed in 7 patients, and 2 of them have survived. Herpes simplex virus-associated HLH was diagnosed in 6 patients, and 2 of them have survived. The overall survival rate for the 20 patients was 40%.. HLH is rare in neonates and has a poor prognosis. Early diagnosis and immediate treatment are required when considering the possibility of herpes simplex virus-associated or familial HLH.

Topics: Acyclovir; Adrenal Cortex Hormones; Antineoplastic Agents, Phytogenic; Antiviral Agents; beta 2-Microglobulin; Consciousness Disorders; Cyclosporine; Erythema; Etoposide; Exanthema; Female; Fetal Distress; Fever; gamma-Globulins; Hematopoietic Stem Cell Transplantation; Herpes Simplex; Humans; Immunologic Factors; Immunosuppressive Agents; Infant, Newborn; Infant, Premature; Japan; L-Lactate Dehydrogenase; Leukocytosis; Lymphohistiocytosis, Hemophagocytic; Male; Ocular Motility Disorders; Plasma Exchange; Prognosis; Respiratory Distress Syndrome, Newborn; Seizures; Severe Combined Immunodeficiency

Herpes virus encephalitis is a rare, life-threatening complication of therapy in patients with brain tumors. A surgical therapeutic approach may be needed because the infection can be resistant to acyclovir in immunocompromised patients, and complications and long-term sequelae are frequent.. We present the case of a right-handed, 6-year-old girl with a brainstem tumor who had herpes virus encephalitis with refractory seizures while on immunosuppressive treatment. The virus was resistant to acyclovir but responded to gancyclovir. The patient developed local refractory brain edema with right uncal herniation.. To reduce the intracranial pressure, internal decompressive craniotomy was performed, which consisted of a right temporal lobectomy that allowed us to remove the focal necrotic-hemorrhagic tissue, decrease inflammation, and avoid subsequent chronic gliotic scarring. Clinical improvement was clear with prompt recovery and acute control of seizures. The only remaining deficits were mild memory and attention impairments. Seizures did not recur in the next 6 months.. Antiviral resistance should be suspected in immunocompromised patients with herpes virus encephalitis if there is no early response to acyclovir. If uncal herniation of the nondominant temporal lobe develops, temporal lobectomy, as an internal decompressive procedure, can be lifesaving. Lobectomy stopped the acute refractory seizures and can be considered a good approach to prevent later epilepsy, with only mild residual cognitive deficits.

Topics: Acyclovir; Anterior Temporal Lobectomy; Antineoplastic Combined Chemotherapy Protocols; Antiviral Agents; Brain Stem Neoplasms; Child; Electroencephalography; Encephalitis, Herpes Simplex; Female; Humans; Magnetic Resonance Imaging; Radiotherapy; Seizures; Temporal Lobe

Herpes simplex encephalitis (HSE) can cause high mortality and morbidity in children. Since local data of HSE in children are rare, we performed a retrospective study to evaluate the prognostic factors and outcome of HSE in Taiwan.. Children were enrolled into this study if they were diagnosed as having encephalitis and also had positive polymerase chain reaction for herpes simplex virus (HSV) from cerebrospinal fluid, and/or positive immunoglobulin M or at least four-fold elevation of immunoglobulin G against HSV type 1 or type 2 from serum during the period from December 1, 1984 to January 31, 2003.. Forty patients were enrolled in this study. Twenty six patients (65%) had good outcome and 14 (35%) had poor outcome. No mortality or recurrence was found. Three-fifths of the patients were between 1 year and 6 years of age. Fever (75%) was the most common finding at admission, followed by seizures (63%), lethargy (60%), and altered consciousness (48%). Seizure and lethargy at the time of admission were more common in the poor outcome group (71% vs 58% and 64% vs 58%). Abnormal computed tomography/magnetic resonance imaging findings were found in 63% of patients in whom the examinations were performed. Abnormal electroencephalogram (EEG) findings were noted in 79% of tested patients. Acyclovir was used to treat 29 patients (73%). Abnormal neuroimaging or EEG findings were more prevalent in patients with poor outcome (75% vs 55% and 92% vs 71%), as well as delayed (>/=3 days) initiation of acyclovir therapy (92% vs 71%). There was no significant difference between the poor and good outcome groups in gender, age distribution, and clinical presentation.. As we cannot predict the outcome of patients with HSE in the early beginning of illness and delay of treatment may cause disaster, early diagnosis and prompt acyclovir initiation are important requirements for successful management.

Topics: Acyclovir; Adolescent; Antiviral Agents; Child; Child, Preschool; Diagnosis, Differential; Encephalitis, Herpes Simplex; Female; Fever; Humans; Infant; Lethargy; Male; Retrospective Studies; Seizures; Taiwan; Treatment Outcome; Unconsciousness

Cutaneous herpes simplex virus type 2 (HSV-2) infection was recognized at 19 days of age in a 1415-g female infant born at 31 weeks of gestation. Cerebrospinal fluid (CSF) HSV polymerase chain reaction (PCR) was negative, and MRI of the brain was normal. After a 14-day course of high-dose intravenous acyclovir, the infant developed a cutaneous recurrence at 38 days of age. CSF HSV PCR again was negative. She was subsequently begun on oral acyclovir to prevent cutaneous reactivation of HSV. At 3 months of age, the infant developed HSV encephalitis as manifested by fever, seizures, abnormal CSF indices, abnormal brain MRI, and positive CSF HSV PCR. No cutaneous disease was present. It is not known whether the HSV encephalitis in our patient represented reactivation of previously unrecognized central nervous system infection or new onset of central nervous system disease as a result of spread from other tissue or site to the brain. The failure of oral acyclovir to prevent such an occurrence, however, highlights gaps in our understanding of the pathogenesis of neonatal HSV disease and questions the use of acyclovir suppression to prevent neurologic sequelae.

Topics: Acyclovir; Administration, Oral; Antiviral Agents; Brain; Encephalitis, Herpes Simplex; Female; Herpes Simplex; Herpesvirus 2, Human; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Injections, Intravenous; Magnetic Resonance Imaging; Polymerase Chain Reaction; Radiography; Recurrence; Seizures; Virus Activation

Topics: Acyclovir; Adult; Antigens, Viral; Brain; Cerebral Arteries; DNA, Viral; Early Diagnosis; Encephalitis, Herpes Simplex; Female; Frontal Lobe; Headache; Herpesvirus 1, Human; Humans; Magnetic Resonance Imaging; Meninges; Neurons; Seizures; Temporal Lobe; Tomography, X-Ray Computed; Treatment Outcome

Herpes simplex virus type 1 (HSV-1) is an important pathogen related to epilepsy. We have shown previously that corneal inoculation of mice with HSV-1 causes acute spontaneous behavioral and electrophysiological seizures and increases hippocampal excitability and kainite-induced seizure susceptibility. In this study, we aimed to determine whether early-life HSV-1 infection in mice might cause short- and long-term enhanced susceptibility to pentylenetetrazol (PTZ)-induced seizures and to evaluate whether early antiviral drug therapy was effectively ameliorating this deficit. Seizure threshold was calculated by the latency of onset of the myoclonic jerk, generalized clonus, and maximal tonic-clonic convulsion. We demonstrate that the localization of viral antigens was predominantly within the bilateral temporal areas (amygdala, piriform, and entorhinal cortex) of HSV-1-infected mice. We also present evidence that mice of all HSV-1-infected groups had a shorter latency and higher severity to PTZ-induced seizures than in age-matched, mock-infected controls. Treatment of HSV-1-infected mice with valacyclovir, a potent inhibitor of HSV-1 replication, produced a dose-dependent decrease in the signs of neurological deficits, pathological damages, and PTZ-induced seizure severity. Our results are consistent with the hypothesis that early-life HSV-1 infection leads to persistent enhancement of neuronal excitability in limbic circuits, which could result in an overall increased propensity to induce seizures later in life. Additionally, prompt optimal antiviral therapy effectively decreases seizure susceptibility in HSV-1-infected mice by limiting the level of viral replication and inflammatory response induced by virus. The present study provides not only experimental evidence, but also a new therapeutic strategy in HSV-1-associated human epilepsy.

Topics: Acyclovir; Animals; Antiviral Agents; Behavior, Animal; Body Weight; Disease Susceptibility; Dose-Response Relationship, Drug; Drug Interactions; Electroencephalography; Electromyography; Herpes Simplex; Herpesvirus 1, Human; Hippocampus; Immunohistochemistry; Infections; Male; Mice; Mice, Inbred BALB C; Pentylenetetrazole; Reaction Time; Seizures; Staining and Labeling; Time Factors; Valacyclovir; Valine; Virus Latency

Topics: Acyclovir; Antiviral Agents; Child, Preschool; Epstein-Barr Virus Infections; Female; Humans; Male; Seizures

Topics: Acyclovir; Aged; Humans; Kidney Failure, Chronic; Male; Seizures; Valacyclovir; Valine

Encephalitis is a rare complication of primary varicella-zoster virus (VZV) infection in immunocompetent children.. The clinical and laboratory findings of two girls with VZV-related encephalitis are reported.. Both children presented with focal epileptic seizures, corresponding to cortical/subcortical as well as white matter lesions. The first showed a typical vesicular skin rash. She was easily diagnosed and made a rapid recovery during acyclovir and steroid treatment. In the second girl, a preceding measles-mumps-rubella virus vaccination and the absence of skin vesicles were misleading with respect to the diagnosis, which was finally proven by IgG seroconversion and intrathecal synthesis of IgG antibodies to VZV. She developed left parieto-occipital tissue necrosis and recovered only transiently during initial acyclovir/steroid treatment. Eight weeks after onset, progressive white matter demyelination and the occurrence of erythema nodosum in the lower limbs necessitated a second 4-month course of oral steroids. The VZV PCR from cerebrospinal fluid was negative in both children.. Primary VZV infection may cause severe encephalitis that may occur without skin vesicles and lead to a chronic course with systemic vasculitis. The coincidence of vaccination and neurologic diseases offers no proof per se of a causal relationship.

Topics: Acyclovir; Anti-Inflammatory Agents; Antibodies, Viral; Antiviral Agents; Brain; Child, Preschool; Diagnosis, Differential; Encephalitis, Varicella Zoster; Female; Hemianopsia; Herpesvirus 3, Human; Humans; Infant; Recurrence; Seizures; Steroids; Treatment Outcome

A 46-year-old woman with a triplet pregnancy developed seizures, an oculogyric crisis and a homonymous hemianopia post-natally. Abnormal neuroimaging studies and lumbar puncture suggested possible cerebral vasculitis. Treatment with aciclovir and prednisolone resulted in a slow resolution of symptoms. This case highlights the difficulty in distinguishing eclampsia from rarer neurological causes of peripartum seizures.

Topics: Acyclovir; Anti-Inflammatory Agents; Cerebrospinal Fluid; Diagnosis, Differential; Eclampsia; Female; Hemianopsia; Humans; Leukocyte Count; Lymphocyte Count; Magnetic Resonance Angiography; Middle Aged; Prednisolone; Pregnancy; Puerperal Disorders; Seizures; Spinal Puncture; Tomography, X-Ray Computed; Triplets; Vasculitis, Central Nervous System

Herpes simplex virus is the most common cause of acute viral encephalitis in children. Due to the variety of possible clinical manifestations the diagnosis is often overlooked in the early stages of the disease. Anti-viral therapy with acyclovir should be started whenever HSE is suspected. When there is further deterioration under virostatic therapy, a brain biopsy should be performed to verify the diagnosis. But even when the adequate medical therapy is established, massive brain edema and brain shift resulting in tentorial herniation can develop. Up to now the reported mortality of these patients is still around 30%. Here we report on a child with severe necrotizing herpes simplex encephalitis who developed severe tentorial herniation due to a right-sided mass lesion. The patient's status markedly improved after decompressive anterior temporal lobe resection. To our knowledge a similar case has not yet been reported in the literature. We suggest that anterior temporal lobe resection and decompressive craniotomy is of benefit in selected cases with tentorial herniation because both decompression and reduction of infectious material can be achieved.

Topics: Acyclovir; Antiviral Agents; Biopsy; Encephalitis, Viral; Female; Herpes Simplex; Humans; Infant; Magnetic Resonance Imaging; Neurologic Examination; Seizures; Simplexvirus; Temporal Lobe; Tomography, X-Ray Computed

To report a case of acute renal failure and neurotoxicity following administration of oral acyclovir.. Medical record of the patient, case reports identified by MEDLINE.. Data were abstracted from relevant published data by Johnson and reviewed by the remaining authors.. A 69-year-old woman was diagnosed with herpes zoster and oral acyclovir was prescribed by her local physician. After approximately two days the patient was taken to the emergency department of a local hospital with signs of acute confusion and acute renal failure. Medications included oxycodone/acetaminophen, alprazolam, prazepam, and digoxin. Pertinent laboratory abnormalities included serum digoxin 4.1 mumol/L, white blood cell count 17.6 x 10(9)/L, blood urea nitrogen (BUN) 24 mmol/L of urea, and serum creatinine 305 mumol/L (patient baseline is 11 mmol/L of urea and 91.5 serum creatinine mumol/L, respectively). Because of increasing lethargy and a focal seizure, she was transferred to our institution. Despite an extensive workup, no organic cause of her altered mental status and acute renal failure was identified. Four days after discontinuation of the acyclovir, without specific intervention, the patient's mental status improved and her BUN and serum creatinine concentrations had decreased to 21 mmol/L of urea and 190.6 mumol/L, respectively. On day 5, the patient was alert and oriented to name, place, year, and month. On day 9, her renal function and mental status had returned to baseline and she was discharged.. Acute renal failure and neurotoxicity are usually associated with intravenous acyclovir. The temporal relationship between the initiation of oral acyclovir therapy and the onset of adverse events, supported by published data of a few similar cases, strongly implicate oral acyclovir as the cause of this patient's acute renal failure and neurotoxicity. This case suggests that elderly patients with mild increased serum creatinine concentrations may be at increased risk and should be monitored closely for signs and symptoms of acute renal failure and neurotoxicity.

Topics: Acute Kidney Injury; Acyclovir; Administration, Oral; Aged; Blood Urea Nitrogen; Confusion; Creatinine; Female; Humans; Seizures; Substance-Related Disorders

Since Acyclovir is available a sufficient treatment of herpes simplex virus (HSV) encephalitis exists. Febrile convulsions may occur as the initial manifestation of an encephalitis, particularly of an HSV encephalitis. Within 25 months out of 151 children with febrile convulsions five children with complicated febrile convulsions were admitted at the pediatric department of Graz. In all children HSV antibodies in serum and cerebrospinal fluid (CSF) were negative and the diagnosis of an HSV encephalitis was made by positive CSF HSV polymerase chain reaction (PCR). Therefore, in any suspected case, i.e. in any case of a complicated febrile convulsion, CSF should be investigated including a HSV PCR to rapidly confirm or exclude HSV encephalitis.

Topics: Acyclovir; Cerebrospinal Fluid; Child, Preschool; Diagnosis, Differential; Encephalitis; Female; Fever; Humans; Infant; Magnetic Resonance Imaging; Male; Polymerase Chain Reaction; Seizures; Simplexvirus