Agustin Legido

Acute Disseminated Encephalomyelitis in Children: Discordant Neurologic and Neuroimaging Abnormalities and Response to Plasmapheresis

Objectives. To describe our experience with acute disseminated encephalomyelitis (ADEM), focusing on (1) the relationship between clinical course and MRI findings and (2) the response to plasmapheresis in a subgroup of patients. Methods. A retrospective record review was conducted of 13 children who were admitted as inpatients with the diagnosis of ADEM during the period 1998–2003. Results. Diagnosis was established by clinical signs and symptoms, cerebrospinal fluid changes and multifocal involvement of deep gray and white matter based on MRI. Initial therapy was high-dose methylprednisolone and intravenous immunoglobulin in 12 patients. One child improved spontaneously. Six of 12 children did not improve with corticosteroid treatment. All 6 had an acute progressive course neurologically, and 5 of them also showed a delay in the onset of neuroimaging changes, eventually developing lesions in the deep gray matter and brainstem. This latter group received 5 sessions of plasmapheresis and recovered over the course of several months with varying degrees of residual neurologic deficits. Conclusions. Presentation of ADEM with delayed development of MRI lesions in deep gray matter and brainstem may herald a prolonged clinical course and lack of response to glucocorticoid therapy. Plasmapheresis might be an effective therapeutic intervention in these patients. The role of plasmapheresis versus corticosteroids and intravenous immunoglobulin as a primary treatment of ADEM needs to be investigated further.

IL-15 Treatment during Acute Simian Immunodeficiency Virus (SIV) Infection Increases Viral Set Point and Accelerates Disease Progression despite the Induction of Stronger SIV-Specific CD8+ T Cell Responses

In this study, we examined the effect of in vivo treatment of acutely SIV-infected Mamu-A*01+ rhesus macaques with IL-15. IL-15 treatment during acute infection increased viral set point by 3 logs and accelerated the development of simian AIDS in two of six animals with one developing early minimal lesion SIV meningoencephalitis. Although IL-15 induced a 2- to 3-fold increase in SIV-specific CD8+ T cell and NK cell numbers at peak viremia and reduced lymph node (LN) SIV-infected cells, this had no impact on peak viremia and did not lower viral set point. At viral set point, however, activated SIV-specific CD8+ T cells and NK cells were reduced in the blood of IL-15-treated animals and LN SIV-infected cells were increased. Week 30 LN from IL-15-treated animals had significantly increased Gag-specific CD8+ T cell numbers, whereas total cell, lymphocyte, and CD4+ T cell numbers were reduced. IL-15 treatment significantly reduced anti-SIV Ab concentrations at week 3 and viral set point. IL-15 increased Ki-67+CD4+ T cells at week 1 of treatment and reduced blood CCR5+ and CD45RA−CD62L− CD4+ T cells. The frequency of day 7 Ki-67+CD4+ T cells strongly correlated with viral set point. These findings suggest that CD4+ T cell activation during acute infection determines subsequent viral set point and IL-15 treatment by increasing such activation elevates viral set point. Finally, IL-15-treated acutely SIV-infected primates may serve as a useful model to investigate the poorly understood mechanisms that control viral set point and disease progression in HIV infection.

Aberrant Localization of the Neuronal Class III b-Tubulin in Astrocytomas A Marker for Anaplastic Potential

c Background.—The class III b-tubulin isotype (bIII) is widely regarded as a neuronal marker in development and neoplasia. In previous work, we have shown that the expression of bIII in neuronal/neuroblastic tumors is differentiation dependent. In contrast, the aberrant localization of this isotype in certain nonneuronal neoplasms, such as epithelial neuroendocrine lung tumors, is associated with anaplastic potential. Objective.—To test the generality of this observation, we investigated the immunoreactivity profile of bIII in astrocytomas. Design.—Sixty archival, surgically excised astrocytomas (8 pilocytic astrocytomas, WHO grade 1; 18 diffuse fibrillary astrocytomas, WHO grade 2; 4 anaplastic astrocytomas, WHO grade 3; and 30 glioblastomas, WHO grade 4), were studied by immunohistochemistry using anti-bIII monoclonal (TuJ1) and polyclonal antibodies. A monoclonal antibody to Ki-67 nuclear antigen (NC-MM1) was used as a marker for cell proliferation. Antibodies to glial fibrillary acidic protein (GFAP) and BM89 synaptic vesicle antigen/synaptophysin were used as glial and neuronal markers, respectively. Results.—The bIII immunoreactivity was significantly greater in high-grade astrocytomas (anaplastic astrocytomas and glioblastomas; median labeling index [MLI], 35%; interquartile range [IQR], 20%‐47%) as compared with diffuse fibrillary astrocytomas (MLI, 4%; IQR, 0.2%‐21%) (P , .0001) and was rarely detectable in pilocytic astrocytomas (MLI, 0%; IQR, 0%‐0.5%) (P , .0001 vs high-grade astrocytomas; P , .01 vs diffuse fibrillary astrocytomas). A highly significant, grade-dependent relationship was observed between bIII and Ki-67 labeling and malignancy, but this association was stronger for Ki-67 than for bIII (bIII, P , .006; Ki-67, P , .0001). There was co-localization of bIII and GFAP in neoplastic astrocytes, but no BM89 synaptic vesicle antigen/synaptophysin staining was detected. Conclusions.—In the context of astrocytic gliomas, bIII immunoreactivity is associated with an ascending gradient of malignancy and thus may be a useful ancillary diagnostic marker. However, the significance of bIII-positive phenotypes in diffuse fibrillary astrocytomas with respect to prognostic and predictive value requires further evaluation. Under certain neoplastic conditions, bIII expression is not neuron specific, calling for a cautious interpretation of bIII-positive phenotypes in brain tumors. (Arch Pathol Lab Med. 2001;125:613‐624)

Intravenous Levetiracetam in Children With Epilepsy

Intravenous levetiracetam recently became available for use in patients aged >16 years. There are few data about its safety and efficacy in children. We retrospectively analyzed data from children treated with intravenous levetiracetam. Ten patients (6 female, 4 male), aged 3 weeks to 19 years, were treated with intravenous levetiracetam at a mean dose of 50.5 mg/kg/day for a mean duration of 4.9 days. Four patients received intravenous levetiracetam for acute repetitive seizures/status epilepticus, and three as replacement for oral levetiracetam because administration of oral levetiracetam was temporarily infeasible. One patient each received intravenous levetiracetam for seizure prophylaxis during brain biopsy, as maintenance treatment after acute seizures, and as substitute for sodium valproate. Three of four patients with acute repetitive seizures/status epilepticus became seizure-free; the fourth patient had a partial reduction in seizure frequency. All three patients who received intravenous levetiracetam as substitute for oral levetiracetam tolerated the switch well. The other three patients were seizure-free on intravenous levetiracetam. No serious adverse effects were observed, and all patients completed treatment with intravenous levetiracetam for the intended period. Intravenous levetiracetam may be effective in various clinical situations requiring intravenous administration of an antiepileptic drug.

Spectrum of Polysomnographic Abnormalities in Children With Epilepsy

This study sought to evaluate polysomnographic abnormalities in a cohort of 40 children with epilepsy who underwent a sleep study because of various sleep complaints. Retrospective analyses included polysomnographic variables, antiepileptic drugs, type of epilepsy, and seizure control. The subgroup with epilepsy and obstructive sleep apnea syndrome was compared with 11 children who manifested uncomplicated obstructive sleep apnea syndrome. Thirty-three patients (83%) exhibited snoring (42.5%), sleep-disordered breathing (obstructive hypoventilation, 12.5%; obstructive sleep apnea, 20%; and upper-airway resistance syndrome, 7.5%), or periodic limb movements of sleep (10%). Children with poor seizure control demonstrated significantly lower sleep efficiency, a higher arousal index, and a higher percentage of rapid-eye-movement sleep compared with children who were seizure-free or exhibited good seizure control. Patients with epilepsy and obstructive sleep apnea had significantly a higher body mass index, longer sleep latency, a higher arousal index, and a lower apnea-hypopnea index, but significantly more severe desaturation compared with patients with uncomplicated obstructive sleep apnea. A significant proportion of children with epilepsy referred for polysomnography with diverse sleep problems manifest sleep-disordered breathing, including obstructive sleep apnea syndrome.

Class III β-Tubulin Is Constitutively Coexpressed With Glial Fibrillary Acidic Protein and Nestin in Midgestational Human Fetal Astrocytes: Implications for Phenotypic Identity

Class III &bgr;-tubulin isotype (&bgr;III-tubulin) is widely regarded as a neuronal marker in developmental neurobiology and stem cell research. To test the specificity of this marker protein, we determined its expression and distribution in primary cultures of glial fibrillary acidic protein (GFAP)-expressing astrocytes isolated from the cerebral hemispheres of 2 human fetuses at 18 to 20 weeks of gestation. Cells were maintained as monolayer cultures for 1 to 21 days without differentiation induction. By immunofluorescence microscopy, coexpression of &bgr;III-tubulin and GFAP was detected in cells at all time points but in spatially distinct patterns. The numbers of GFAP+ cells gradually decreased from Days 1 to 21 in vitro, whereas &bgr;III-tubulin immunoreactivity was present in 100% of cells at all time points. &bgr;-III-tubulin mRNA and protein expression were demonstrated in cultured cells by reverse-transcriptase-polymerase chain reaction and immunoblotting, respectively. Glial fibrillary acidic protein+/&bgr;-III-tubulin-positive cells coexpressed nestin and vimentin but lacked neurofilament proteins, CD133, and glutamate-aspartate transporter. Weak cytoplasmic staining was detected with antibodies against microtubule-associated protein 2 isoforms. Confocal microscopy, performed on autopsy brain samples of human fetuses at 16 to 20 gestational weeks, revealed widespread colocalization of GFAP and &bgr;III-tubulin in cells of the ventricular/subventricular zones and the cortical plate. Our results indicate that in the midgestational human brain, &bgr;III-tubulin is not neuron specific because it is constitutively expressed in GFAP+/nestin+ presumptive fetal astrocytes.

Polysomnographic findings in children with headaches.

Although previous studies suggested a relationship between headache and sleep disturbances, polysomnographic findings in children with headache are rarely described. We investigated polysomnographic findings in children with headaches, and correlated them with headache type and severity, body mass index, and medical treatment. Analysis of polysomnographic findings of 90 children with migraine (60), chronic migraine (11), tension headache (6), and nonspecific headache (13) indicated that sleep-disordered breathing was more frequent among children with migraine (56.6%) and nonspecific headache (54%) vs chronic migraine (27%). Tension headache was not associated with sleep-disordered breathing. In the nonspecific headache group, children with sleep-disordered breathing had higher body mass indexes (P = 0.008). Severe migraine and chronic migraine were associated with shorter sleep time, longer sleep latency, and shorter rapid eye movement and slow-wave sleep. Fifty percent of children with tension headache manifested bruxism vs 2.4% of children with nontension headache (odds ratio, 1.95; 95% confidence interval, 1.2-4.34). Our results support an association between migraine and sleep-disordered breathing, and between tension headache and bruxism, in children. Moreover, disrupted sleep architecture with reduced rapid eye movement and slow-wave sleep in severe and chronic migraine headaches may support an intrinsic relationship between sleep and headache disorders.

5q14.3 Deletion Manifesting as Mitochondrial Disease and Autism: Case Report

Mitochondrial disorders are usually associated with defects of 1 or more of the 5 complexes (I to V) of the electron transport chain, or respiratory chain. Complex I and IV are the 2 most frequent abnormalities of the electron transport chain in humans. The authors report the case of a 12-year-old boy with dysmorphic facies, mental retardation, autism, epilepsy, and leg weakness. Buccal swab electron transport chain analysis revealed severe decrease in complex IV and mild reduction in complex I activity levels. Chromosomal microarray studies, using array-based comparative genomic hybridization, revealed a 1-Mb deletion in the 5q14.3 region. This case illustrates that this deletion can be associated with complex I and IV deficits, hence manifesting as a mitochondrial disease. It could be hypothesized that genes that either encode or regulate the expression and/or assembly of complex IV or I subunits are located within the deleted region of 5q14.3.

Mitochondrial Dysfunction in Autism

Using data of the current prevalence of autism as 200:10,000 and a 1:2000 incidence of definite mitochondrial (mt) disease, if there was no linkage of autism spectrum disorder (ASD) and mt disease, it would be expected that 1 in 110 subjects with mt disease would have ASD and 1 in 2000 individuals with ASD would have mt disease. The co-occurrence of autism and mt disease is much higher than these figures, suggesting a possible pathogenetic relationship. Such hypothesis was initially suggested by the presence of biochemical markers of abnormal mt metabolic function in patients with ASD, including elevation of lactate, pyruvate, or alanine levels in blood, cerebrospinal fluid, or brain; carnitine level in plasma; and level of organic acids in urine, and by demonstrating impaired mt fatty acid β-oxidation. More recently, mtDNA genetic mutations or deletions or mutations of nuclear genes regulating mt function have been associated with ASD in patients or in neuropathologic studies on the brains of patients with autism. In addition, the presence of dysfunction of the complexes of the mt respiratory chain or electron transport chain, indicating abnormal oxidative phosphorylation, has been reported in patients with ASD and in the autopsy samples of brains. Possible pathogenetic mechanisms linking mt dysfunction and ASD include mt activation of the immune system, abnormal mt Ca(2+) handling, and mt-induced oxidative stress. Genetic and epigenetic regulation of brain development may also be disrupted by mt dysfunction, including mt-induced oxidative stress. The role of the purinergic system linking mt dysfunction and ASD is currently under investigation. In summary, there is genetic and biochemical evidence for a mitochondria (mt) role in the pathogenesis of ASD in a subset of children. To determine the prevalence and type of genetic and biochemical mt defects in ASD, there is a need for further research using the latest genetic technology such as next-generation sequencing, microarrays, bioinformatics, and biochemical assays. Because of the availability of potential therapeutic options for mt disease, successful research results could translate into better treatment and outcome for patients with mt-associated ASD. This requires a high index of suspicion of mt disease in children with autism who are diagnosed early.

Chronic sorrow and coping in families of children with epilepsy.

&NA; Epilepsy, a common problem in child neurology, affects the entire family. There is a potential for such psychosocial consequences as parental chronic sorrow and alterations in coping. In this study, 67 parents completed brief questionnaires about their sorrow and coping styles. Results demonstrated chronic sorrow as measured by the Adapted Burke Questionnaire (10.45±7.9). Interestingly, the total score was not significantly different between parents of children with refractory and nonrefractory epilepsy or parents of children with comorbid or without comorbid conditions. Selection of the individual item disbelief, however, was significantly increased in parents of children with nonrefractory epilepsy, and selection of the item anger was significantly increased in parents of children with comorbid conditions. Parental coping styles were similar to those reported in the normative data for the instrument used, the Coping Health Inventory for Parents (CHIP). The correlation between chronic sorrow and coping was significant between the grief component of sorrow and Coping Pattern II of the CHIP. Implications for practice include earlier identification of parental feelings of sorrow and coping styles, which may contribute to a positive outcome.