An audit of CT brain findings in adults with new-onset seizures in a resource restricted setting in South Africa

SA Journal of Radiology ISSN: (Online) 2078-6778, (Print) 1027-202X Page 1 of 7 Original Research An audit of CT brain findings in adults with new-onset seizures in a resource restricted setting in South Africa Authors: Sabelo H. Mabaso1 Deepa Bhana-Nathoo1 Susan Lucas1 Affiliations: 1 Department of Radiology, Faculty of Health Sciences, Chris Hani Baragwanath Hospital, University of the Witwatersrand, Johannesburg, South Africa Corresponding author: Sabelo Mabaso, Dates: Received: 05 Sept. 2021 Accepted: 02 Nov. 2021 Published: 20 Jan. 2022 How to cite this article: Mabaso SH, Bhana-Nathoo D, Lucas S. An audit of CT brain findings in adults with new-onset seizures in a resource restricted setting in South Africa. S Afr J Rad. 2022;26(1), a2294. https://doi.org/10.4102/sajr. v26i1.2294 Copyright: © 2022. The Authors. Licensee: AOSIS. This work is licensed under the Creative Commons Attribution License. Background: Globally, adults presenting with seizures account for 1% – 2% of visits to emergency departments (EDs), of which 25% are new-onset seizures. Neuroimaging is essential as part of the initial workup. Multiple studies have demonstrated abnormal CT brain (CTB) findings in these patients. Objectives: To review the CTB findings in adults presenting with new-onset seizures in a resource restricted setting. Method: A retrospective review of 531 CTBs was conducted at a tertiary hospital in Gauteng on adults presenting to the ED with new-onset seizures. Results: The mean age of the patients was 45.6 ± 17.1 years, and the male to female ratio was 1.2:1. Generalised and focal seizure types were almost equally represented. Of the total 531 patients, 168 (31.6%) were HIV positive. The CTB findings were abnormal in 257 (48.4%) patients, albeit vascular pathology accounted for 21.9%. Infective pathology accounted for 14.1% with a statistically significant association with HIV (p = 0.003). Trauma related pathology was 2.4%, whilst neoplastic pathology was seen in 3.0%. Other causes included congenital pathology, calcifications, atrophy and gliosis. Clinical factors associated with abnormal CTB findings were age ≥ 40 years, HIV infection, hypertension, focal seizures, low Glasgow Coma Scale (GCS), raised cerebrospinal fluid (CSF) protein and presence of lymphocytes. Conclusion: A high yield of abnormal CTB findings was noted in adult patients who presented with new-onset seizures, supporting the use of urgent CTB in patients with certain clinical risk factors. Patients without these risk factors can be scanned within 24–48 h in a resource restricted setting. Keywords: new-onset; first-onset; adult-onset; seizure; CT findings. Introduction Globally, adults presenting with seizures account for up to 2% of visits to medical emergency departments (EDs)1,2,3,4 and of these, 25% are new-onset seizures.1,5 It is estimated that 5% – 10% of the population will experience a seizure in their lifetime.3,6,7 According to Gavvala and Schuele,5 seizures represent ‘a transient occurrence of signs and symptoms due to excessive neuronal activity in the brain’. They may be classified simply as focal (affecting a single cerebral hemisphere), generalised (affecting both hemispheres) or unknown1,5 In a clinical setting, seizures are defined in a specific manner. Gavvala and Scheule5 described them as follows: unprovoked seizure, occurring without precipitating factors; acute asymptomatic seizure, occurring in close temporal relationship with a transient brain insult; focal seizure, affecting one part of cerebral hemisphere; generalised seizure, distributed in both cerebral hemispheres; and epilepsy, an enduring predisposition to generate seizures. The estimated incidence rate of adult-onset seizures is 81.7 per 100 000 per year in developing countries compared to 45.0 per 100 000 per year in developed countries, as reported by Ba-Diop et al.8 The incidence rate of new-onset adult seizures is higher in HIV positive populations.9 Another study noted that the majority of patients that were severely immunosuppressed had an underlying, identifiable intracranial abnormality,10 confirming the predisposition of patients with advanced HIV to opportunistic infections as a cause of new-onset seizures. Read online: Scan this QR code with your smart phone or mobile device to read online. Patients with new-onset seizures require imaging as part of their clinical workup.1 Multiple international studies have demonstrated varying degrees of abnormal CT brain (CTB) findings,3,5,7 however, the urgency or optimal timing of imaging has not yet been determined. Computed tomography is the initial imaging of choice, being the most practical, especially in the emergency http://www.sajr.org.za Open Access Page 2 of 7 setting and for those requiring follow-up imaging to monitor disease progression.6,7 Magnetic resonance imaging (MRI) may be utilised as supplementary imaging, where CTB findings are inconclusive or for further characterisation.3,5 The purpose of this study was to determine the underlying CTB findings in adults with new-onset seizures and to identify specific risk factors, if any, that may contribute to the urgency or timing of imaging. Research methods and design A retrospective cross-sectional study of 531 adult patients was conducted, reviewing the CTB findings in cases with new-onset seizures at a tertiary hospital in Gauteng, South Africa, between 01 January 2016 and 31 December 2018. Patients with missing data, illegible reports, those presenting with acute trauma, repeat scans for patients with a known diagnosis and CTB findings not reviewed by a consultant radiologist were excluded from the study. Clinical information including patient age, sex, type of seizure (generalised, focal or status epilepticus) and comorbidities (including HIV status) were accessed and recorded from the hospital picture archiving and communication system (PACS). Relevant laboratory results were accessed from the National Health Laboratory Services (NHLS) and relevant clinical data were recorded and tabulated using an anonymous data collection sheet. Categorical variables were expressed as numbers and percentages and compared with the chi-square test. Continuous variables with a normal distribution were expressed as means and standard deviation (s.d.). The median and interquartile ranges (IQR) were used for continuous variables with a non-normal distribution. The one-way analysis of variance (ANOVA) was used to compare normally distributed continuous variables and the Kruskal-Wallis rank test was used to compare medians for non-normal data. Differences between groups were considered statistically significant at p < 0.05. All analyses were conducted using STATA MP version 13.0 (StataCorp, Texas). Ethical considerations The study was approved by Human Research Ethics Committee of the University of the Witwatersrand, certificate number M190609. Participant consent was not required as this was a retrospective record (...truncated)