Hirosato Inoue

Human herpesvirus 6 encephalitis associated with hypersensitivity syndrome

Hypersensitivity syndrome, a serious systematic reaction to a limited number of drugs, is associated with the reactivation of human herpesvirus 6. A 56‐year‐old man developed acute limbic encephalitis followed by multiple organ failure during the course of toxic dermatitis induced by aromatic anticonvulsants. The clinical features of skin eruptions, high fever, eosinophilia, and atypical lymphocytosis were compatible with drug hypersensitivity syndrome. The patient showed seroconversion for human herpesvirus 6, and polymerase chain reaction detected human herpesvirus 6 DNA in the cerebrospinal fluid. To our knowledge, this is the first report of human herpesvirus 6 encephalitis associated with hypersensitivity syndrome.

Parainfectious Encephalomyeloradiculitis Associated with Herpes Simplex Virus 1 DNA in Cerebrospinal Fluid

We describe a patient with acute encephalomyeloradiculitis associated with herpes simplex virus 1 (HSV-1) DNA in the cerebrospinal fluid (CSF), and we also review 4 similar cases previously reported from Japan. A 59-year-old man presented with acute encephalitis and urinary retention. Initially, coma and CSF pleocytosis improved with acyclovir treatment, but brain stem encephalitis, transverse myelitis, and lumbosacral polyradiculitis subsequently occurred. These conditions responded to corticosteroid therapy and immunoadsorption plasmapheresis. Polymerase chain reaction detected HSV-1 DNA in the CSF during acute encephalitis but not thereafter. Serial magnetic resonance imaging revealed transient lesions in the thalamus and basal ganglia on both sides of the brain and in the pons, spinal cord, and cauda equina. Acute encephalomyeloradiculitis is a unique neurological syndrome that may be caused by HSV-1 infection of the central nervous system.

Hypertrophic cranial nerve roots in CIDP

A 61-year-old man presented with painful dysesthesia/dysarthria (3 months) and sensorimotor impairment (13 years). Chronic inflammatory demyelinating polyradiculoneuritis (CIDP) was confirmed 4 years earlier by …

Acute measles encephalitis in adults

Sirs: Acute measles encephalitis (AME) commonly occurs in children [12]. The pathogenetic mechanism has not been fully elucidated. Limited information is available about AME in adults. We report 2 cases of adult AME. Case 1: A 20-year-old woman developed coma 3 days after she had developed a high-grade fever with Koplik spots followed by a rash. Routine blood tests showed evidence of a mild inflammation. The IgG and IgM titers of antimeasles antibodies were elevated in both the serum (IgG, 1:128; IgM, 1:14.7) and cerebrospinal fluid (IgG, 1:12.8; IgM, 1:14.7). The patient received betamethasone (12 mg/d) and gamma globulin (5 g/d) intravenously from day 6 of the illness. Her level of consciousness gradually improved beginning on day 60. On day 270, she was discharged without residual motor symptoms, although mild psychomotor impairment persisted. On day 2, T2-weighted and FLAIR images showed foci of hyperintense signal bilaterally in the deep cerebral white matter and deep gray matter. These foci of abnormal signal intensity were most prominent on day 30 (Fig. 1A–C) and were still present, with marked brain atrophy, on day 120. On day 60, areas of high-intensity signal in FLAIR images were seen transiently in the right cerebellar hemisphere and both occipital lobes (Fig. 1D and E). Case 2: A 27-year-old woman developed personality changes characterized by an unusually euphoric and cheerful mood 4 days after she had developed a highgrade fever with Koplik spots followed by a rash. Tests of higher cognitive function revealed anterograde and retrograde amnesia, impaired delayed recall, and overall frontal lobe dysfunction. Routine blood tests were normal. IgG titers of antimeasles antibodies were elevated in both the serum (1:571) and cerebrospinal fluid (1:21.8). She was treated with prednisolone (45 mg/d orally) from day 37 of the illness. Her amnesia and personality changes gradually resolved and disappeared completely by day 60. T2-weighted and FLAIR images showed disseminated foci of hyperintense signal bilaterally in the deep cerebral white matter, deep gray matter, and limbic system. These abnormal lesions were most prominent on day 40 (Fig. 1F–H) and had resolved 1 year later. Six clinically well-documented cases of adult AME have been reported from Japan, including our cases (Table 1) [4, 7, 9, 10]. The mean interval from the appearance of rash to onset of encephalitis was 4 days. Most reported adult cases had severe neurological dysfunction, including coma; symptoms reached a plateau within a week. Acute psychotic symptoms are rare but may occur without severe neurological deficit, as in our case 2. With magnetic resonance imaging, lesions are seen within the cerebral cortex, subcortical white matter, periventricular white matter, deep cerebral white matter, basal ganglia, internal capsule, limbic system, and brainstem, but most frequently in the cerebral white matter. The distribution of lesions seen on magnetic resonance imaging closely resembles that of acute disseminated encephalomyelitis (ADEM) [1, 2, 6, 11, 13]. Cases of adult AME usually have neurological sequelae of varying severity. Therapy with corticosteroids and immunoglobulin may provide a relatively good outcome, but the therapeutic dosage and efficacy are unclear. Adult AME usually presents with rapid neurological deterioration and extensive MRI lesions and may be associated with poor outcome. Because maternally derived transplacental measles antibodies, which correlate negatively with the severity of clinical manifestations, gradually decrease in children with age [14, 15], the clinical presentation of adult AME may be more severe than that of childhood AME. Demyelination has been considered important in the pathogenetic mechanism of AME [3, 8]. Indeed, the extensive radiological lesions and severe neurological manifestations of adult AME resemble those of the encephalopathic form of ADEM [5]. Adult AME may have more severe and widespread clinical features than other demyelinating disorders in the central nervous system.

Acute motor sensory axonal neuropathy associated with Henoch-Schönlein purpura

A 41-year-old man was admitted with progressive tetraparesis with hypoesthesia. He also presented with purpura in both legs. After admission, joint pain, gastrointestinal tract bleeding, and renal dysfunction developed. A nerve conduction study revealed reduced amplitude of the motor and sensory nerve action potential, with normal conduction velocity. A skin biopsy showed leukocytoclastic vasculitis, indicating Henoch-Schönlein purpura (HSP). After administration of corticosteroids, the symptom completely disappeared. The present case is the first report in Japan of HSP associated clinically and electrophysiologically with confirmed acute motor sensory axonal neuropathy. Common pathogenesis might have a role for development for two distinct disorders.