A case of acute encephalopathy with biphasic seizures and late reduced diffusion associated with Streptococcus pneumoniae meningoencephalitis

Acute encephalopathy with biphasic seizures and late restricted diffusion temporally associated with human bocavirus infection

Acute encephalitis is a syndromic diagnosis. In the last two decades, a unique clinico-radiological entity, named acute encephalopathy with biphasic seizures and late restricted diffusion (AESD), has been reported in children from Asia. It is characterised by an acute febrile illness with seizures and encephalopathy, with some initial improvement followed by a second flurry of seizures and deep encephalopathy, 3-4 days later. MRI may show a pattern of 'bright tree appearance'. An aetiological agent may not always be identified but an infectious trigger is proposed. Immunomodulatory therapy has been tried with variable results. The prognosis is variable, and children are usually left with neurological sequelae including epilepsy and cognitive impairment. We describe a female infant who presented with the typical clinico-radiological syndrome of AESD and human bocavirus was identified in the stool. She received steroids and antiepileptic drugs. She has persistent cognitive impairment at follow-up but remained seizure free.

Acute encephalopathy with biphasic seizures and late reduced diffusion (central sparing type)—MRI and MR spectroscopy findings

Acute encephalopathy with biphasic seizure and late reduced diffusion (AESD) is a clinico-radiologic syndrome of acute encephalopathy characterized by biphasic seizure and altered consciousness in acute phase followed by restricted diffusion in bilateral cerebral parenchyma on magnetic resonance imaging (MRI) in the subacute stage. Here, we present the MRI and magnetic resonance spectroscopy (MRS) findings in a case of AESD presenting in 4-year child and diagnosed based on clinico-radiological correlation.

Acute encephalopathy with biphasic seizures and late reduced diffusion associated with Streptococcus sanguinis sepsis

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) develops in association with systemic as well as central nervous system (CNS) viral or bacterial infections. AESD is most often noted with influenza or human herpesvirus 6 infection in previously healthy infants. However, AESD has also been reported in an infant with developmental retardation and in a mentally and motor-disabled adolescent. Here, we report the case of a 4- year-old female with significant development delay due to spinal muscular atrophy, who developed AESD during Streptococcus sanguinis sepsis with no apparent CNS infection. Although the patient had extremely high serum procalcitonin (45.84 ng/mL, reference; <0.4) on admission indicating a poor prognosis, she was successfully managed for sepsis and AESD.

Septic Encephalopathy Characterized by Acute Encephalopathy with Biphasic Seizures and Late Reduced Diffusion and Early Nonconvulsive Status Epilepticus

Infection, whether viral or bacterial, can result in various forms of brain dysfunction (encephalopathy). Septic encephalopathy (SE) is caused by an excessive immune reaction to infection, with clinical features including disturbed consciousness and seizures. Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is usually accompanied by viral infection in children and is characterized by biphasic seizures and impaired consciousness. The initial neurologic symptom of AESD is typically a febrile seizure that frequently lasts longer than 30 minutes. However, the possible forms this seizure takes are unclear. For example, it is unknown if nonconvulsive status epilepticus (NCSE) could be an early seizure symptomatic of AESD. In addition, thus far no cases of combined SE and AESD have been reported. Here, we describe the first reported case of SE with AESD that notably demonstrated NCSE as an early seizure.

A missed diagnosis: acute encephalopathy with biphasic seizures and late reduced diffusion

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is a very rare encephalopathy subtype which is characterized by biphasic seizures and disturbance of consciousness in the acute stage followed in the subacute stage by restricted diffusion in the subcortical white matter and finally resulting in cerebral atrophy on magnetic resonance imaging. Although exact pathogenesis of AESD is uncertain, the etiology of AESD has been attributed to viral and bacterial infection. Here we report a case of AESD in a 15-year-old mentally and motor retarded patient, diagnosed based on clinicoradiological correlation.

Acute encephalopathy with biphasic seizures and late reduced diffusion

Acute encephalopathy with biphasic seizures and reduced diffusion (AESD) is a syndrome of encephalopathy characterized by biphasic seizures and altered consciousness in the acute stage followed in the subacute stage by restricted diffusion in the subcortical white matter on magnetic resonance imaging. The etiology of AESD has been attributed to viral infection like influenza A and human herpes virus 6. The exact pathogenesis of AESD is uncertain. Here we report a case of AESD, diagnosed based on clinicoradiological correlation.

Analysis of multiple B-value diffusion-weighted imaging in pediatric acute encephalopathy

Acute encephalopathy is a disease group more commonly seen in children. It is often severe and has neurological sequelae. Imaging is important for early diagnosis and prompt treatment to ameliorate an unfavorable outcome, but insufficient sensitivity/specificity is a problem. To overcome this, a new value (fraction of high b-pair (F_H)) that could be processed from clinically acceptable MR diffusion-weighted imaging (DWI) with three different b-values was designed on the basis of a two-compartment model of water diffusion signal attenuation. The purpose of this study is to compare F_H with the apparent diffusion coefficient (ADC) regarding the detectability of pediatric acute encephalopathy. We retrospectively compared the clinical DWI of 15 children (1–10 years old, mean 2.34, 8 boys, 7 girls) of acute encephalopathy with another 16 children (1–11 years old, mean 4.89, 9 boys, 7 girls) as control. A comparison was first made visually by mapping F_H on the brain images, and then a second comparison was made on the basis of 10 regions of interest (ROIs) set on cortical and subcortical areas of each child. F_H map visually revealed diffusely elevated F_H in cortical and subcortical areas of the patients with acute encephalopathy; the changes seemed more diffuse in F_H compared to DWI. The comparison based on ROI revealed elevated mean F_H in the cortical and subcortical areas of the acute encephalopathy patients compared to control with significant difference (P<0.05). Similar findings were observed even in regions where the findings of DWI were slight. The reduction of mean ADC was significant in regions with severe findings in DWI, but it was not constant in the areas with slighter DWI findings. The detectability of slight changes of cortical and subcortical lesions in acute encephalopathy may be superior in F_H compared to ADC.