Etiology and Types of Seizures in Patients Presenting to a Tertiary Care Hospital in Karachi: A Cross-Sectional Study.

Introduction Epilepsy is a burdensome disorder for affected individuals and community. There is limited data available on the epidemiological aspects of seizures in Pakistan and further research is necessary. We aimed to fill this gap by studying this information in epilepsy patients presenting to our neurology department. The purpose of this study is to evaluate the causes and types of seizures among the target population. Method This is a cross-sectional study conducted at the Department of Neurology, Dr. Ruth K.M. Pfau Civil Hospital Karachi. In this study we evaluated the causes and types of seizures among patients presenting to our department during the two-year study duration (January 2018-December 2019). Informed consent was taken. Detailed history was taken including features of seizure episodes, age at first seizure, family history and comorbid conditions. Relevant investigations were carried out. The data was compiled to deduce the relevant information using SPSS v20.0. T-test and Chi-square were used for analyzing the data. Results A total of 996 patients presented during the study duration. Primary seizures were found in 58% cases while secondary seizures were found in 42% cases. This distribution was more equal in children with 49.6% primary seizures and 50.4% secondary seizures; the gap widened in adults with 64.3% primary seizures and 35.7% secondary seizures. The most common cause of secondary seizures was neonatal encephalopathy which was present in 18.7% patients, followed by traumatic head injury in 18.2% patients. Central nervous system (CNS) infection was the cause in 17.9% patients, cerebral tumors in 14.1% patients, stroke in 11.5%, metabolic encephalopathy in 7.4%, febrile seizures in 6.5% and CNS malformations in 5.7% patients. The top three causes in children were neonatal encephalopathy (28.3%), CNS infections (19.3%) and febrile seizures (12.7%). Adults with secondary seizures were diagnosed most often with head trauma (25.2%), cerebral tumors (19.9%) and stroke (18.4%) as causative factors. The most common type of seizures was generalized onset tonic-clonic seizures which was found in 73.0% patients followed by focal to bilateral tonic-clonic seizures in 8.9% patients. Other types of seizures included focal aware seizures in 5.0%, mixed seizure types in 4.2%, focal impaired awareness seizures in 3.1%, absence seizures in 2.7%, myoclonic seizures in 2.0% and atonic seizures in 1.0% patients. Seizures in children were mostly generalized onset tonic-clonic seizures (75.4%), mixed seizure types (5.7%) and focal to bilateral tonic-clonic seizures (5.2%). In adults the three most common types corresponded to the overall result: generalized onset tonic-clonic seizures (71.2%), focal to bilateral tonic-clonic seizures (11.6%) and focal aware seizures (6.6%). Conclusion We found that the most common cause of seizures overall in our study population was primary seizures, though primary and secondary seizures were more evenly present in children. Among secondary causes neonatal encephalopathy stood out as the most common cause in children; head trauma was the predominant cause in adults. Most common type of seizures overall and in adults was generalized onset tonic-clonic seizures, followed by focal to bilateral tonic-clonic and focal aware seizure types. Pediatric patients presented most often with generalized onset tonic-clonic seizures, followed by mixed seizure types and focal to bilateral tonic-clonic seizures.