Role of Routine Benzodiazepin in Eliciting Classical Electroencephalogram (EEG) Response in Suspected Sub-Acute Sclerosing Panencephalitis (SSPE) Cases

Abstract

Background: EEG could be normal or atypical in spite of suggestive clinical features and positive measles Ab of SSPE cases which could have typical EEG pattern after Benzodiazepine. Objectives: The purpose of the present study was to find out the necessity of administration of benzodiazepine during EEG recording of SSPE cases as well as to compare the efficacy of diazepam and midazolam in eliciting EEG pattern. Methodology: This double blind, parallel, single centered, non-randomized clinical trial was conducted in the Department of Pediatric Neurology at National Institute of Neurosciences, Dhaka, Bangladesh from July 2014 to June 2015 for a period of 1 (one) year. All the clinical and investigational suspected cases of sub-acute Sclerosing Pan- encephalitis (SSPE) children in both sexes were included as study population. Others neurodegenerative diseases including Wilson’s disease were excluded from this study. Patients were divided into two groups named as group A who were given diazepam and the other group B was given midazolam in IV during EEG recording. The clinical outcomes were measured and were recorded in a pre-designed data sheet. Result: The characteristic typical periodic slow wave complex (PSWC) was found only in 8 (30.8%) patients among the 26 (100.0%) before intervention with benzodiazepines. The remaining 18 (69.2%) had non-typical PSWC of which 10 (38.5%) were normal, 3 (11.5%) with atypical PSWC and 5 (19.2%) were with other EEG findings. After intervention with benzodiazepines, 23 (88.5%) had shown typical PSWC and only 3 (11.5%) had non-typical PSWC. Among the typical PSWC cases after intervention, 8 (30.8%) had normal EEG initially, 5 (19.2%) had other EEG finding, 2 (7.7%) had non-typical PSWC and 8 (30.8%) had typical PSWC from the beginning. Of the 3 (11.5%) of the non-typical PSWC of intervention group, 2 (7.7%) had shown no changes in EEG from the beginning and 1 (3.8%) had shown other EEG finding. The difference between before and after intervention was actually statistically extremely significant (p < 0.0001). Among the two study groups, 11 (84.6%) and 12 (92.3%) patients had shown typical PSWC respectively in Group A and Group B after intervention. The non-typical PSWC was seen in 2 (15.4%) of Group A and 1 (7.7%) of Group B patients. The statistical difference between the two groups was not significant (p > 0.05). Conclusion: The role of benzodiazepine is very obvious in eliciting the typical EEG pattern in SSPE patients which has shown the characteristic PSWC in EEG in most cases.