Status Epilepticus: Etiology, Outcome and Predictors of Mortality

ObjectiveThis study was designed to determine the etiology of status epilepticus (SE) andits relation to mortality.Materials and MethodsThis descriptive study was carried out based on the medical records of 40 patients with diagnosis of SE discharged from pediatric hospital of Bandar Abbas between March 2002 and March 2004. Multivariant analysis was pereformed to determine the prevalence of the disorder and the relation between SE and other factors such as gender, age, response to treatment, and mortality. We classified the etiology according to international league against epilepsy (ILAE) classification and also uses another classification regarding underlying causes such as fever (non-CNS infection), central nervous system infection, hypoxia, and metabolic causes.ResultsStatus epilepticus was responsible for 0.3% of all hospital  dmissions during the study period. Based on the ILAE classification, frequencies for acute symptomatic, febrile, progressive encephalopathic, remote, and cryptogenic SE were 42.5%, 32.5%, 10%, 7.5%, and 7.5%, respectively.The most common underlying causes resulting in SE were fever (45%), metabolic disorders (15%), CNS infection (12.5%), chronic neurologic diseases (7.5%), idiopathic (7.5%), hypoxia (5%), drug withdrawal (2.5%), CNS hemorrhage (2.5%), neurodegenerative disease (2.5%), brain abscess (2.5%), and post DPT (Diphteria,Pertusis,Tetanus) vaccination (2.5%). Mortality rate was 25% (80% in the patients younger than 5 years and 40% in those aged less than 1 year). Occurrence of SE and its mortality was found to be related to age (p< 0.05).ConclusionFor SE, if seizures continue for more than 5 minutes, treatment must beinitiated. The outcome is determined by etiology, age, seizure duration and management; however, all we can do is enhance the management and increase its effectiveness

Empirical constraints on the origin of fast radio bursts: volumetric rates and host galaxy demographics as a test of millisecond magnetar connection

The localization of the repeating FRB 121102 to a low-metallicity dwarf galaxy at $z=0.193$, and its association with a quiescent radio source, suggests the possibility that FRBs originate from magnetars, formed by the unusual supernovae in such galaxies. We investigate this via a comparison of magnetar birth rates, the FRB volumetric rate, and host galaxy demographics. We calculate average volumetric rates of possible millisecond magnetar production channels such as superluminous supernovae (SLSNe), long and short gamma-ray bursts (GRBs), and general magnetar production via core-collapse supernovae. For each channel we also explore the expected host galaxy demographics using their known properties. We determine for the first time the number density of FRB emitters (the product of their volumetric birthrate and lifetime), $R_{\rm FRB}\tau\approx 10^4$Gpc$^{-3}$, assuming that FRBs are predominantly emitted from repetitive sources similar to FRB 121102 and adopting a beaming factor of 0.1. By comparing rates we find that production via rare channels (SLSNe, GRBs) implies a typical FRB lifetime of $\approx$30-300 yr, in good agreement with other lines of argument. The total energy emitted over this time is consistent with the available energy stored in the magnetic field. On the other hand, any relation to magnetars produced via normal core-collapse supernovae leads to a very short lifetime of $\approx$0.5yr, in conflict with both theory and observation. We demonstrate that due to the diverse host galaxy distributions of the different progenitor channels, many possible sources of FRB birth can be ruled out with $\lesssim 10$ host galaxy identifications. Conversely, targeted searches of galaxies that have previously hosted decades-old SLSNe and GRBs may be a fruitful strategy for discovering new FRBs and related quiescent radio sources, and determining the nature of their progenitors