[HLA-DRB1 typing in Caucasians patients with neuromyelitis optica]. / HLA-DRB1 en pacientes caucasicos con neuromielitis optica.

INTRODUCTION: The existence of antibodies to aquaporin-4 (AQP-4-ab) has identified neuromyelitis optica (NMO) and multiple sclerosis (MS) as different diseases. Although HLA-DRB1 alleles contribute to MS risk, recent studies suggest that HLA back-ground differs between patients with NMO or MS in non-Caucasians populations. Our study was aimed to analyze HLA-DRB1 distribution in Caucasians NMO patients. SUBJECTS AND METHODS: We recruited a cohort of 22 NMO patients (73% were AQP-4-ab positive), 228 MS patients and 225 healthy controls from Spain and we genotyped the HLA-DRB1 locus. Then, we performed a pool analysis using reported data from 45 NMO patients (53% were AQP-4-ab positive), 156 MS patients and 310 healthy controls from Caucasian French population. RESULTS: In the Spanish cohort, NMO was associated with increased frequency of DRB1*10 allele compared with MS (odds ratio, OR = 15.1; 95% confidence interval, 95% CI = 3.26-69.84; p = 0.012). In the pooled analysis, by comparison with healthy controls, NMO was associated with increased frequency of DRB1*03 allele (OR = 2.27; 95% CI = 1.44-3.58; p < 0.0008) which was related to AQP-4-ab seropositivity (OR = 2.74; 95% CI = 1.58-4.77; p < 0.0008). By contrast, MS was associated with increased frequency of DRB1*15 allele (OR = 2.09; 95% CI = 1.62-2.68; p < 0.0008) and decreased frequency of DRB1*07 allele (OR = 0.58; 95% CI = 0.44-0.78; p < 0.0008). CONCLUSIONS: Caucasian patients with NMO and MS have a different HLA-DRB1 allelic distribution. DRB1*03 allele seems to contribute to NMO seropositivity. Multicenter collaborative efforts are needed to adequately address the genetic contribution to NMO susceptibility.

[Reversible "man-in-the-barrel" syndrome caused by hypoxic-ischemic encephalopathy]. / Síndrome del "hombre en barril" reversible causado por encefalopatía hipóxico-isquémica.

INTRODUCTION: Hypoxic-ischemic encephalopathy can lead to different clinical presentations, such as bilateral cortical borderzone infarctions due to cerebral hypoperfusion (especially after cardiopulmonary arrest), which would cause a "man-in-the-barrel" syndrome if the anterior circulation is affected. This syndrome has multiple etiologies, both central (bilateral frontal and/or pyramidal decussation lesions and cervical spinal cord lesions) as well as peripheral ones such as multifocal motor neuropathy. CASE REPORT: We report the case of a 19-year-old man who developed a "man-in-the-barrel" syndrome with bilateral and proximal upper limb brachial diplegia after bilateral watershed infarctions involving distal fields of the middle and the anterior cerebral artery due to cerebral hypoperfusion in a comatose patient without internal carotid obstruction. CONCLUSIONS: The rate of death in this syndrome is higher than 90% and it predicts a worse outcome in comatose patients. Nevertheless, our patient has had complete clinical improvement.

Valproate-induced hyperammonemic encephalopathy.

Valproate-induced hyperammonemic encephalopathy (VHE) is an unusual complication characterized by a decreasing level of consciousness, focal neurological deficits, cognitive slowing, vomiting, drowsiness, and lethargy. We have thoroughly reviewed the predisposing factors and their screening, the biochemical and physiopathological mechanisms involved, the different treatments described, and those that are being investigated. Etiopathogenesis is not completely understood, although hyperammonemia has been postulated as the main cause of the clinical syndrome. The increase in serum ammonium level is due to several mechanisms, the most important one appearing to be the inhibition of carbamoylphosphate synthetase-I, the enzyme that begins the urea cycle. Polytherapy with several drugs, such as phenobarbital and topiramate, seems to contribute to hyperammonemia. Hyperammonemia leads to an increase in the glutamine level in the brain, which produces astrocyte swelling and cerebral edema. There are several studies that suggest that treatment with supplements of carnitine can lead to an early favorable clinical response due to the probable carnitine deficiency induced by a valproate (VPA) treatment. Development of the progressive confusional syndrome, associated with an increase in seizure frequency after VPA treatment onset, obliges us to rule out VHE by screening for blood ammonium levels and the existence of urea cycle enzyme deficiency, such as ornithine carbamoyltransferase deficiency. Electroencephalography (EEG) is characterized by signs of severe encephalopathy with continuous generalized slowing, a predominance of theta and delta activity, occasional bursts of frontal intermittent rhythmic delta activity, and triphasic waves. These EEG findings, as well as clinical manifestations and hyperammonemia, tend to normalize after VPA withdrawal.

Síndrome del «hombre en barril»reversible causado por encefalopatíahipóxico-isquémica / Reversible «man-in-the-barrel» syndrome caused by hypoxic-ischemic encephalopathy

Introducción. La encefalopatía hipóxico-isquémica puede producirdiferentes cuadros clínicos, entre los que se engloban aquellosproducidos por hipoperfusión en territorio frontera que pueden originarun síndrome del «hombre en barril» si está afectada la circulaciónanterior. Este síndrome presenta múltiples etiologías, tanto centrales(lesiones frontales bilaterales y/o en la decusación piramidal ylesiones en la médula espinal cervical) como periféricas como la neuropatíamotora multifocal.Caso clínico. Presentamos el caso clínico de un paciente de19 años que presentó un síndrome del «hombre en barril» con diplejíabraquial bilateral de carácter proximal secundario a lesiones bilateralespor hipoperfusión en territorio frontera de la circulación anterioren el contexto de hipotensión en un estado comatoso, pero sinestenosis de arterias carótidas internas.Conclusiones. Este síndrome clínico presenta una tasa de mortalidadsuperior al 90 %, y se considera un factor de mal pronósticoen pacientes en coma. No obstante, en nuestro caso el paciente hapresentado una completa resolución clínica (AU)

Introduction. Hypoxic-ischemic encephalopathy can lead todifferent clinical presentations, such as bilateral cortical borderzoneinfarctions due to cerebral hypoperfusion (especially aftercardiopulmonary arrest), which would cause a «man-in-the-barrel» syndrome if the anterior circulation is affected. This syndromehas multiple etiologies, both central (bilateral frontal and/orpyramidal decussation lesions and cervical spinal cord lesions) aswell as peripheral ones such as multifocal motor neuropathy.Case report. We report the case of a 19 year old man whodeveloped a «man-in-the-barrel» syndrome with bilateral andproximal upper limb brachial diplegia after bilateral watershedinfarctions involving distal fields of the middle and the anteriorcerebral artery due to cerebral hypoperfusion in a comatose patientwithout internal carotid obstruction.Conclusions. The rate of death in this syndrome is higherthan 90% and it predicts a worse outcome in comatose patients.Nevertheless, our patient has had complete clinical improvement (AU)