Clinically Approximated Hypoperfused Tissue in Large Vessel Occlusion Stroke.

Background and Purpose: Patient selection for thrombectomy of acute ischemic stroke caused by large vessel occlusion in the delayed time window (>6 hours) is dependent on delineation of clinical-core mismatch or radiological target mismatch using perfusion imaging. Selection paradigms not involving advanced imaging and software processing may reduce time to treatment and broaden eligibility. We aim to develop a conversion factor to approximately determine the volume of hypoperfused tissue using the National Institutes of Health Stroke Scale (NIHSS) score (clinically approximated hypoperfused tissue [CAT] volume) and explore its ability to identify patients eligible for thrombectomy in the late-time window. Methods: We performed a retrospective analysis of anterior circulation large vessel occlusion strokes at 3 comprehensive stroke centers. Demographic, clinical, and imaging (computed tomography perfusion processed using RAPID, IschemaView) information was analyzed. A conversion factor, which is a multiple of the NIHSS score (for NIHSS score <10 and ≥10), was derived from an initial cohort to calculate CAT volumes. Accuracy of CAT-based thrombectomy eligibility criteria (using CAT volume instead of Tmax >6 seconds volume) was tested using DEFUSE-3 criteria (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3) eligibility as a gold standard in an independent cohort. Results: Of the 309 large vessel occlusion strokes (age, 70±14, 46% male, median NIHSS 16 [12­20]) included in this study, 38% of patients arrived beyond 6 hours of time from last known well. Conversion factors derived (derivation cohort-center A: 187) based on median values of Tmax>6 second volume for NIHSS score <10 subgroup was 15 and for NIHSS score ≥10 subgroup was 6. Subsequently calculated CAT volume­based eligibility criteria yielded a sensitivity of 100% and specificity of 92% in detecting DEFUSE-3 eligible patients (area under the curve, 0.92 [95% CI, 0.82­1]) in the validation cohort (center B and C:122). Conclusions: Clinical severity of stroke (NIHSS score) may be used to calculate the volume of hypoperfused tissue during large vessel occlusion stroke. CAT volumes for NIHSS score <10 (using a factor of 15) and ≥10 (using a factor of 6) subgroups can accurately identify DEFUSE-3-eligible patients.

[Autoimmune encephalitis mediated by antibodies against the N-Nethyl-N-Aspartate receptor: report of four cases in Peru]. / Encefalitis autoinmune mediada por anticuerpos contra el receptor N-Metil-N-Aspartato: reporte de cuatro casos en Perú.

Autoimmune encephalitis with antibodies against the N-methyl-D-aspartate receptor (anti-NMDAR) is a disorder mediated by antibodies against neural surface antigens, whose early diagnosis and timely treatment improve the prognosis of the disease. Four cases with the definitive diagnosis of autoimmune encephalitis by anti-NMDAR are presented, treated at the National Institute of Neurological Sciences in Lima-Peru. All patients had epileptic seizures and three cases developed a refractory epileptic state. In addition, three patients presented neuropsychiatric alterations, dyskinesias, and dysautonomia. Two cases required ventilatory support. All presented an abnormal electroencephalogram; two cases had pleocytosis in cerebrospinal fluid, and only one showed brain abnormalities on MRI. Regarding treatment, all patients received methylprednisolone immunotherapy and only two of them required plasma exchange for an ineffective response to corticosteroid treatment. After 12 months of hospital discharge, three patients were free of epileptic seizures and only one case did not achieve functional independence. These cases show that anti-NMDAR encephalitis is a treatable condition and its early recognition together with appropriate treatment (immunotherapy/plasmapheresis) are essential for a favorable evolution.

La encefalitis autoinmune por anticuerpos contra el receptor N-metil-D-aspartato (anti-NMDAR) es un desorden mediado por anticuerpos contra antígenos de superficie neuronal, cuyo diagnóstico temprano y tratamiento oportuno mejoran el pronóstico de la enfermedad. Se presentan cuatro casos con el diagnóstico definitivo de encefalitis autoinmune por anti-NMDAR, tratados en el Instituto Nacional de Ciencias Neurológicas en Lima-Perú. Todos los pacientes presentaron crisis epilépticas y tres casos desarrollaron un estado epiléptico refractario. Asimismo, tres pacientes presentaron alteraciones neuropsiquiátricas, discinesias y disautonomías. Dos casos requirieron soporte ventilatorio. Todos presentaron un electroencefalograma anormal, dos casos tuvieron pleocitosis en líquido cefalorraquídeo, y sólo uno mostró anormalidades cerebrales en la resonancia magnética. Respecto al tratamiento, todos los pacientes recibieron inmunoterapia con metilprednisolona y sólo dos de ellos requirieron plasmaféresis por respuesta ineficaz al tratamiento con corticoides. A los 12 meses del alta hospitalaria, tres pacientes quedaron libre de crisis epilépticas y sólo un caso no logró la independencia funcional. Estos casos muestran que la encefalitis anti-NMDAR es una condición tratable y su reconocimiento temprano junto con un tratamiento adecuado (inmunoterapia/plasmaféresis) son esenciales para una evolución favorable.

Encefalitis autoinmune mediada por anticuerpos contra el receptor N-Metil-N-Aspartato: reporte de cuatro casos en Perú / Autoimmune encephalitis mediated by antibodies against the N-Nethyl-N-Aspartate receptor: report of four cases in Peru

RESUMEN La encefalitis autoinmune por anticuerpos contra el receptor N-metil-D-aspartato (anti-NMDAR) es un desorden mediado por anticuerpos contra antígenos de superficie neuronal, cuyo diagnóstico temprano y tratamiento oportuno mejoran el pronóstico de la enfermedad. Se presentan cuatro casos con el diagnóstico definitivo de encefalitis autoinmune por anti-NMDAR, tratados en el Instituto Nacional de Ciencias Neurológicas en Lima-Perú. Todos los pacientes presentaron crisis epilépticas y tres casos desarrollaron un estado epiléptico refractario. Asimismo, tres pacientes presentaron alteraciones neuropsiquiátricas, discinesias y disautonomías. Dos casos requirieron soporte ventilatorio. Todos presentaron un electroencefalograma anormal, dos casos tuvieron pleocitosis en líquido cefalorraquídeo, y sólo uno mostró anormalidades cerebrales en la resonancia magnética. Respecto al tratamiento, todos los pacientes recibieron inmunoterapia con metilprednisolona y sólo dos de ellos requirieron plasmaféresis por respuesta ineficaz al tratamiento con corticoides. A los 12 meses del alta hospitalaria, tres pacientes quedaron libre de crisis epilépticas y sólo un caso no logró la independencia funcional. Estos casos muestran que la encefalitis anti-NMDAR es una condición tratable y su reconocimiento temprano junto con un tratamiento adecuado (inmunoterapia/plasmaféresis) son esenciales para una evolución favorable.

ABSTRACT Autoimmune encephalitis with antibodies against the N-methyl-D-aspartate receptor (anti-NMDAR) is a disorder mediated by antibodies against neural surface antigens, whose early diagnosis and timely treatment improve the prognosis of the disease. Four cases with the definitive diagnosis of autoimmune encephalitis by anti-NMDAR are presented, treated at the National Institute of Neurological Sciences in Lima-Peru. All patients had epileptic seizures and three cases developed a refractory epileptic state. In addition, three patients presented neuropsychiatric alterations, dyskinesias, and dysautonomia. Two cases required ventilatory support. All presented an abnormal electroencephalogram; two cases had pleocytosis in cerebrospinal fluid, and only one showed brain abnormalities on MRI. Regarding treatment, all patients received methylprednisolone immunotherapy and only two of them required plasma exchange for an ineffective response to corticosteroid treatment. After 12 months of hospital discharge, three patients were free of epileptic seizures and only one case did not achieve functional independence. These cases show that anti-NMDAR encephalitis is a treatable condition and its early recognition together with appropriate treatment (immunotherapy/plasmapheresis) are essential for a favorable evolution.