Low-dose clozapine-related seizure: A case report and literature review

BACKGROUND Treatment-resistant schizophrenia is a severe form of schizophrenia characterized by poor response to at least two antipsychotic drugs and is typically treated with clozapine.However,clozapine lowers the epileptic threshold,leading to seizures,which are severe side effects of antipsychotics that result in multiple complications.Clozapine-related seizures are generally considered to be dose-dependent and especially rare in the low-dose(150-300 mg/d)clozapine treated population.Due to clinical rarity,little is known about its clinical characteristics and treatment.CASE SUMMARY A 62-year-old Chinese man with a 40-year history of treatment-resistant schizophrenia presented to the Emergency Department with symptoms of myoclonus,consciousness disturbance and vomiting after taking 125 mg clozapine.Upon admission,the patient had a suddenly generalized tonic-clonic seizure lasting for about half a minute with persistent disturbance of consciousness,fever,cough and bloody sputum,which was considered to be low-dose clozapine-related seizure.After antiepileptic and multiple anti-infection treatments,the patient was discharged without epileptic or psychotic symptoms.CONCLUSION Our aim is to highlight the early prevention and optimal treatment of clozapine related seizure through case analysis and literature review.

Interhemispheric functional connectivity for Alzheimer's disease and amnestic mild cognitive impairment based on the triple network model

The purpose of this study was to explore the differences in interhemispheric functional connectivity in patients with Alzheimer’s disease(AD) and amnestic mild cognitive impairment(aMCI) based on a triple network model consisting of the default mode network(DMN), salience network(SN), and executive control network(ECN). The technique of voxel-mirrored homotopic connectivity(VMHC) analysis was applied to explore the aberrant connectivity of all patients. The results showed that:(1) the statistically significant connections of interhemispheric brain regions included DMN-related brain regions(i.e. precuneus, calcarine, fusiform, cuneus, lingual gyrus, temporal inferior gyrus, and hippocampus), SN-related brain regions(i.e. frontoinsular cortex), and ECN-related brain regions(i.e. frontal middle gyrus and frontal inferior);(2) the precuneus and frontal middle gyrus in the AD group exhibited lower VMHC values than those in the aMCI and healthy control(HC) groups, but no significant difference was observed between the a MCI and HC groups; and(3) significant correlations were found between peak VMHC results from the precuneus and Mini Mental State Examination(MMSE) and Montreal Cognitive Scale(MOCA) scores and their factor scores in the AD, a MCI, and AD plus aMCI groups, and between the results from the frontal middle gyrus and MOCA factor scores in the a MCI group. These findings indicated that impaired interhemispheric functional connectivity was observed in AD and could be a sensitive neuroimaging biomarker for AD. More specifically, the DMN was inhibited, while the SN and ECN were excited. VMHC results were correlated with MMSE and MOCA scores, highlighting that VMHC could be a sensitive neuroimaging biomarker for AD and the progression from aMCI to AD.