Eculizumab in Adolescent Patients With Refractory Generalized Myasthenia Gravis: A Phase 3, Open-Label, Multicenter Study.

BACKGROUND: This study evaluated the efficacy and safety of eculizumab, a terminal complement C5 inhibitor, in juvenile generalized myasthenia gravis (gMG). METHODS: Adolescents aged 12 to 17 years with refractory anti-acetylcholine receptor (AChR) antibody-positive gMG received eculizumab (weekly induction [one to two doses of 600 mg or four doses of 900 mg] followed by maintenance doses [300 to 1200 mg] every two weeks for up to 26 weeks) in a phase 3, open-label multicenter study (NCT03759366). Change from baseline to week 26 in Quantitative Myasthenia Gravis (QMG) total score (primary end point) and secondary end points including Myasthenia Gravis-Activities of Daily Living (MG-ADL) total score, Myasthenia Gravis Composite score, Myasthenia Gravis Foundation of America postintervention status, EuroQol 5-Dimensions (Youth) and Neurological Quality-of-Life Pediatric Fatigue questionnaire scores, as well as pharmacokinetics, pharmacodynamics, and safety, were recorded. RESULTS: Eleven adolescents (mean ± S.D. age 14.8 ± 1.8 years) were enrolled; 10 completed the primary evaluation period. Least-squares mean changes from baseline at week 26 were -5.8 (standard error [SE] 1.2; P = 0.0004) for QMG total score and -2.3 (SE 0.6; P = 0.0017) for MG-ADL total score. Overall, the primary and all secondary efficacy end point analyses met statistical significance from the first assessment and were sustained throughout. Complete terminal complement inhibition was sustained through 26 weeks in all patients. Treatment-emergent adverse events were all mild/moderate and predominantly unrelated to eculizumab. CONCLUSIONS: Eculizumab was effective in reducing disease burden and was well tolerated in adolescents with refractory AChR antibody-positive gMG.

Bias flow rate and ventilation efficiency during adult high-frequency oscillatory ventilation: a lung model study.

BACKGROUND: Bias flow (BF) is essential to maintain mean airway pressure (MAP) and to washout carbon dioxide (CO2) from the oscillator circuit during high-frequency oscillatory ventilation (HFOV). If the BF rate is inadequate, substantial CO2 rebreathing could occur and ventilation efficiency could worsen. With lower ventilation efficiency, the required stroke volume (SV) would increase in order to obtain the same alveolar ventilation with constant frequency. The aim of this study was to assess the effect of BF rate on ventilation efficiency during adult HFOV. METHODS: The R100 oscillator (Metran, Japan) was connected to an original lung model internally equipped with a simulated bronchial tree. The actual SV was measured with a flow sensor placed at the Y-piece. Carbon dioxide (CO2) was continuously insufflated into the lung model ([Formula: see text]CO2), and the partial pressure of CO2 (PCO2) in the lung model was monitored. Alveolar ventilation ([Formula: see text]A) was estimated as [Formula: see text]CO2 divided by the stabilized value of PCO2. [Formula: see text]A was evaluated by setting SV from 80 to 180 mL (10 mL increments, n = 5) at a frequency of 8 Hz, a MAP of 25 cmH2O, and a BF of 10, 20, 30, and 40 L/min (study 1). Ventilation efficiency was calculated as [Formula: see text]A divided by the actual minute volume. The experiment was also performed with an actual SV of 80, 100, and 120 mL and a BF from 10 to 60 L/min (10 L/min increments: study 2). RESULTS: Study 1: With the same setting SV, the [Formula: see text]A with a BF of 20 L/min or more was significantly higher than that with a BF of 10 L/min. Study 2: With the same actual SV, the [Formula: see text]A and the ventilation efficiency with a BF of 30 L/min or more were significantly higher than those with a BF of 10 or 20 L/min. CONCLUSIONS: Increasing BF up to 30 L/min or more improved ventilation efficiency in the R100 oscillator.

Characteristic MRI features of chronic inflammatory demyelinating polyradiculoneuropathy.

We present characteristic magnetic resonance imaging (MRI) features in a pediatric female patient with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Muscle weakness developed at 8 years old and fluctuated during the clinical course over 7 years. Electrophysiological studies showed a demyelination pattern with moderately delayed nerve conduction velocity, as well as dispersion phenomenon. MRI showed marked changes in thickening of the spinal nerve roots and their peripheral nerves in the lumber and brachial plexuses, as well as in the bilateral trigeminal nerves. It is suggested that these MRI features are characteristic and strongly supportive of the diagnosis of CIDP with a prolonged clinical course.

ADORA2A polymorphism predisposes children to encephalopathy with febrile status epilepticus.

OBJECTIVE: Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is a childhood encephalopathy following severe febrile seizures, leaving neurologic sequelae in many patients. However, its pathogenesis remains unclear. In this study, we clarified that genetic variation in the adenosine A2A receptor (ADORA2A), whose activation is involved in excitotoxicity, may be a predisposing factor of AESD. METHODS: We analyzed 4 ADORA2A single nucleotide polymorphisms in 85 patients with AESD. The mRNA expression in brain samples, mRNA and protein expression in lymphoblasts, as well as the production of cyclic adenosine monophosphate (cAMP) by lymphoblasts in response to adenosine were compared among ADORA2A diplotypes. RESULTS: Four single nucleotide polymorphisms were completely linked, which resulted in 2 haplotypes, A and B. Haplotype A (C at rs2298383, T at rs5751876, deletion at rs35320474, and C at rs4822492) frequency in patients was significantly higher than in controls (p = 0.005). Homozygous haplotype A (AA diplotype) had a higher risk of developing AESD (odds ratio 2.32, 95% confidence interval 1.32-4.08; p = 0.003) via a recessive model. mRNA expression was significantly higher in AA than AB and BB diplotypes, both in the brain (p = 0.003 and 0.002, respectively) and lymphoblasts (p = 0.035 and 0.003, respectively). In lymphoblasts, ADORA2A protein expression (p = 0.024), as well as cellular cAMP production (p = 0.0006), was significantly higher in AA than BB diplotype. CONCLUSIONS: AA diplotype of ADORA2A is associated with AESD and may alter the intracellular adenosine/cAMP cascade, thereby promoting seizures and excitotoxic brain damage in patients.

[A case of neurocutaneous melanosis associated with focal cortical dysplasia].

A newborn baby boy presented with giant melanocytic nevi on the face, trunk and extremities, and focal cortical dysplasia on MRI. At 3 months of age, he developed intractable epilepsy, and MRI at 2 years of age revealed a high-intensity area in the bilateral cerebellum on T1-weighted images, indicative of melanosis. Based on the findings of the skin and MRI, we diagnosed the boy with neurocutaneous melanosis. Cytodiagnosis of cerebrospinal fluid showed no malignancies. EEG, magnetoencephalogram and ECD-SPECT indicated that the clonic seizures originated from a focus in the right focal cortical dysplasia. Complications also included sebaceous nevus of the head and face, which was characteristic of sebaceous nevus syndrome, lipoma of the face and cauda equina, and limbal dermoid. Sebaceous nevus syndrome may have been due to certain allelic defects that were independent of those for neurocutaneous melanosis.

Electroencephalography-guided resection of dysembryoplastic neuroepithelial tumor: case report.

A 3-year-old girl presented with a dysembryoplastic neuroepithelial tumor in the right cingulate gyrus manifesting as epilepsy refractory to anticonvulsant medication. Computed tomography and magnetic resonance imaging revealed a cystic tumor in the right cingulate gyrus. The tumor was removed under intraoperative electrocorticography guidance. Abnormal spikes recorded adjacent to the tumor disappeared immediately after total removal. Histological examination showed a multinodular, multicystic structure, satisfying the criteria for the diagnosis of dysembryoplastic neuroepithelial tumor. She has remained seizure-free for more than 4 years without complications. In this case, intraoperative electrocorticography was very useful to identify the possible focus and prevent unnecessary resection of the adjacent tissue. Total removal of the tumor resulted in a dramatic reduction of seizure activity.

Dandy-Walker syndrome and chromosomal abnormalities.

Dandy-Walker syndrome (DWS) is a brain malformation of unknown etiology, but several reports have been published indicating that there is a causal relationship to various types of chromosomal abnormalities and malformation syndromes. In the present article, we present a bibliographical survey of several previously issued reports on chromosomal abnormalities associated with DWS, including our case of DWS found in trisomy 18. There are various types of chromosomal abnormalities associated with DWS; most of them are reported in chromosome 3, 9, 13 and 18. We also summarize some other chromosomal abnormalities and various congenital malformation syndromes.

[Neurological complications during and after the treatment of acute lymphocytic leukemia].

To explore the frequency and prognosis of neurological complications of acute lymphocytic leukemia, retrospective studies were made of patients with acute lymphocytic leukemia. Neurological complications were found in 13 of 100 patients during and after treatment. They were caused by chemotherapy in 8 patients, irradiation therapy in 2, vitamin B1 deficiency in 1, and unknown in 2. Medications primarily relevant to these complications were methotrexate in 5 patients, L-asparaginase in 2, cytosin arabinoside in 1. The patients were diagnosed as having leukoencephalopathy (8), cerebrovascular injury (4), and Wernicke's encephalopathy (1). Symptomatic epilepsy was found in one patient, and mental retardation was seen in three patients during a 2-year course of treatment. We conclude that careful management is required in the treatment of acute lymphocytic leukemia, because of the persistence of neurological complications, although their severity is decreasing with advances in treatment.

Activated remodeling and N-methyl-D-aspartate (NMDA) receptors in cortical dysplasia.

Cortical dysplasia is now recognized as one of the major etiologies causing intractable epilepsy in childhood. Dysplastic cortex displays cortical dyslamination, which is often associated with dysmorphic large neurons and less frequently with balloon cells. The dysmorphic large neurons are commonly located in the subcortical white matter and cerebral cortex, with enlarged nuclei with a single prominent nucleolus and showing aberrant cytoskeletal changes. I have shown that dysmorphic large neurons have several immature types of cytoskeletal proteins, such as the low-molecular-weight form of microtubule-associated protein 2 (MAP2) and MAP1B, which are involved in the outgrowth and modeling of neuronal processes in the immature brain. I have also reported that dysmorphic large neurons also have enhanced gene expression of growth-associated protein GAP43, which is a phosphoprotein enriched at presynaptic nerve terminals and is thought to be involved in axonal outgrowth and plasticity in synaptic connections. Finally, I have shown that the N-methyl-D-aspartate acid (NMDA) receptor R1 gene is up-regulated in the dysmorphic large neurons and nearly normal-sized neurons located in the dysplastic cortex. This evidence suggests that growth of neuronal processes and activated excitatory synaptic remodeling exist in the epileptic conditions of cortical dysplasia.

Doublecortin immunoreactivity in giant cells of tuberous sclerosis and focal cortical dysplasia.

Cerebral cortical lesions of tuberous sclerosis (TSC) and focal cortical dysplasia (FCD) show disturbances in laminar architecture and cellular differentiation. We immunohistochemically studied the expression of doublecortin, a fetal neuronal protein that regulates neuronal migration, in the surgical specimens of five TSC and eight FCD patients. In both TSC and FCD, bizarre giant cells showed a variable degree of doublecortin immunoreactivity. Both cytomegalic neurons and balloon cells were positive. The staining tended to be more intense in TSC than in FCD, although there were exceptional cases in both groups. Doublecortin immunoreactivity of normal-sized neural cells was restricted to a small number of astrocytes, and comparable to that in control patients. The persistent expression of doublecortin by giant cells in the postnatal cerebrum is additional evidence of abnormal differentiation, which may be relevant to the pathogenesis of cortical disarray in TSC and FCD.

The distribution and number of Leu-7 (CD57) positive cells in lung tissue from patients with pulmonary fibrosis.

Leu-7 positive lymphocytes, including natural killer cells, play an important role in the immune system's surveillance function to prevent the development of cancer. The incidence of lung cancer is significantly high in patients with end-stage pulmonary fibrosis. We hypothesized that the number of Leu-7 positive cells may be decreased in areas of severe pulmonary fibrosis. To demonstrate this, Leu-7 positive cells were immunohistochemically stained in 41 lung specimens obtained from patients with idiopathic pulmonary fibrosis and pulmonary fibrosis associated with collagen vascular disorders. The number of Leu-7 positive cells was evaluated according to the pathological findings. In pathologically normal lung, Leu-7 positive cells were mostly found within the capillaries of the septa and rarely in the alveolar space or the stroma. The number of Leu-7 positive cells was 0.69 +/- 0.15 in areas of advanced fibrosis (n = 41), 2.39 +/- 0.60 in areas that had newly developeing fibrosis (n = 41), 1.14 +/- 0.57 in bronchiolitis obliterans organizing pneumonia (n = 9), and 1.35 +/- 0.87 in diffuse alveolar damage (DAD) (n = 11). The number of Leu-7 positive cells in areas of newly developing fibrosis (2.39 +/- 0.60) was significantly higher than that in areas of established fibrosis (0.69 +/- 0.15, P < 0.05). Our present study demonstrates a significant decrease in the number of Leu-7 positive cells in areas of advanced fibrosis. This evidence may partly explain the high incidence of lung cancer associated with pulmonary fibrosis.

An autopsy case of ornithine transcarbamylase deficiency.

We present an autopsy case of ornithine transcarbamylase (OTC) deficiency with grumose degeneration in the dentate nucleus of the cerebellum. The patient had intractable neonatal convulsions and hyperammonemia from the 3rd day after birth. Diagnosis of OTC deficiency was made based on null activity of the enzyme and four-base deletions in exon 9 of the OTC gene. Death was due to sepsis as well as disseminated intravascular coagulation at 1 year and 2 months of age. Neuropathology showed multiple cystic changes and ulegyria in the bilateral frontal and parietal lobes. Multiple cysts were associated with the region, which was infiltrated with macrophages surrounded by astroglia showing palisading pattern. Ferrugination was marked in the thalamus and severe neuronal loss with astrogliotic change in the CA1-2 area of the hippocampus. Grumose degeneration was noted in the dentate nucleus of the cerebellum. This is the first report of grumose degeneration in OTC deficiency.