Ikuhiko Shibuya

A case of clinically mild encephalitis with a reversible splenial lesion (MERS) after mumps vaccination.

We describe for the first time an 8-year-old male patient who demonstrated clinically mild encephalitis with a reversible splenial lesion after mumps vaccination. He suffered from transient hallucinations, nuchal rigidity, and inappropriate antidiuretic hormone secretion syndrome. On the 5th day of admission, his head MRI showed symmetrical high-signal-intensity lesions on T2, FLAIR, and diffusion-weighted images in the splenium of the corpus callosum and in the periventricular white matter, while an apparent diffusion coefficient map showed reduced diffusion. The images were not enhanced by gadolinium. Follow-up MRI on the 16th day of admission revealed none of these abnormalities. His serum IgM and IgG antibodies against the mumps virus were positive according to an enzyme immunoassay. Mumps Torii vaccine strain was isolated from the patients cerebrospinal fluid. Previous reports demonstrated that transient delirious behavior, the syndrome of inappropriate antidiuretic hormone secretion, and good prognosis were the main clinical features of mild encephalitis with a reversible splenial lesion. This case shows that mild encephalitis with a reversible splenial lesion could occur after mumps vaccination.

Prefrontal brain function in children with anorexia nervosa: A near-infrared spectroscopy study

To investigate the prefrontal hemodynamic response during a cognitive task in childhood anorexia nervosa (AN), we measured regional cerebral blood volume changes in terms of changes in hemoglobin concentrations [Hb], using near-infrared spectroscopy (NIRS). Sixteen females with AN (mean age 14.2 years old) and 12 age-matched healthy female control subjects (mean age 14.3 years old) participated in this study. Waveform patterns for [Hb] during the word fluency task differed between the two groups, although their task performances showed no significant difference. In the control group, the [total-Hb] and [oxy-Hb] immediately increased and the [deoxy-Hb] immediately decreased after the beginning of the task and gradually reached the baseline level after the end of the task. The patients with AN were consistently characterized by an unchanged or less fluctuating response pattern of [total-Hb], [oxy-Hb] and [deoxy-Hb] during the task and rest periods. In the AN group, subjects with higher Eating Attitudes Test (EAT-26) scores showed higher [oxy-Hb] during the task. On the other hand, in the control group, subjects with higher EAT-26 scores showed lower [oxy-Hb] during the task. The grand waveforms of each [Hb] during a motor activation task, which was applied as a control task, did not differ significantly between two groups. The different prefrontal hemodynamic responses might indicate that AN subjects might apply fewer brain circuits or fewer neurons per circuit during cognitive tasks and might use different brain circuits in relation to their preoccupation with eating behaviors.

A serial 18FDG-PET study of a patient with SSPE who had good prognosis by combination therapy with interferon alpha and ribavirin

We describe a 15-year-old girl with subacute sclerosing panencephalitis (SSPE) in stage II who was treated with isoprinosine, intraventricular interferon alpha (IFN-α), and ribavirin for 3 years. She is alive at three years from onset and studies at school with the assistance of a special educational teacher. To assess residual brain function, serial (18)FDG-positron emission tomography (PET) was performed three times to measure cortical metabolism: at onset, a year later, and three years later. At onset, PET study revealed preserved glucose metabolism of the cerebral cortex. In serial PET study, glucose metabolism of the cerebral cortex was also preserved even after three years. Although SSPE is a progressive disease of the neuronal system, and typically leads to death in approximately 2-3 years, the neurological prognosis of our case was good. We consider that combination therapy in the very early stage without hypometabolism in the cerebral cortex may be effective for SSPE.

Eyelid myoclonia with absences occurring during the clinical course of cryptogenic myoclonic epilepsy of early childhood.

We describe a 15-year-old boy with learning difficulties and eyelid myoclonia with absences (EMA). Myoclonic jerks of the extremities and trunk occurred 9 years before the onset of EMA, when the patient was 6. At that time, we diagnosed him with cryptogenic myoclonic epilepsy of early childhood, because he manifested mainly myoclonic jerks with generalized 3- to 6-Hz spike/polyspike-and-slow-wave complexes on EEG, normal neurological examination, good response to antiepileptic drugs, and no evidence of previous brain damage. This is an unusual case showing that myoclonic epilepsy of early childhood can evolve to EMA. Although the question of whether EMA is a seizure type or an epilepsy syndrome remains controversial, our case suggests that EMA is a seizure type during the clinical course of a particular kind of myoclonic epilepsy.

Pitfalls in diagnosing psychogenic nonepileptic seizures in a sexually abused child.

A six-year-old girl living in a residential care facility because of previous sexual abuse at home showed intractable seizures with epileptic discharges on interictal EEG. The features of the attacks were sudden impaired consciousness, only in daytime while eating, studying, and walking, with no motor acts and continuing for several minutes to one hour. She could not recall the attacks, and anticonvulsants showed no effects. She gradually became irritated and antisocial, exhibiting impulsive and hyperactive behavior. Interictal EEG repeatedly showed diffuse irregular spikes and wave complexes. The attacks continued sporadically for more than two years and ceased after disclosure of repeated sexual abuse by a boy at the residential care facility. In this case, delayed diagnosis of psychogenic nonepileptic seizures was associated with diagnostic difficulty of dissociative symptoms in a child, the presence of epileptiform EEG in an abused child, and undetected sexual abuse in a residential care facility, the potential for which pediatric neurologists should be aware. These pitfalls are discussed in the context of previous related literature.