Electroencephalographic Findings in a Cohort of Egyptian Systemic Lupus Erythematosus Patients with Neuropsychiatric Manifestations

Background and Objective Neuropsychiatric manifestations are frequently reported in 75% of Systemic Lupus Erythematosus (SLE) patients and that varied from mild subtle signs: headache or mood disturbance to life threatening conditions: acute confusional state, major fits, stroke or transverse myelitis. Electroencephalography (EEG) was used to determine whether there is a lateralized pattern of electrophysiologic dysfunction in SLE patients or not. So, this study was done to describe EEG findings in a cohort of Egyptian SLE patients with Neuropsychiatric SLE (NPSLE), its possible correlation with any of the disease activity parameters and comparing them to patients with Non-NPSLE. Patients and Methods This case-control study was conducted on 60 SLE patients who fulfilled the 2015 ACR/SLICC Classification Criteria for SLE. They were classified into 2 groups: 30 patients with NPSLE as cases and 30 patients without NPSLE (Non-NPSLE) as controls. All patients were subjected to detailed medical history taking together with full clinical examination and calculations of SLE disease activity using the SLE disease activity index (SLEDAI) score. Laboratory investigations including CBC, ESR, CRP, BUN, creatinine, urine analysis, P/C ratio, C3, C4, Lupus Anticoagulant (LAC) and Anticardiolipin (ACL) antibodies and EEG were done for all patients. MRI brain was done for patients with NPSLE. Results There were 6 neuropsychiatric manifestations in the NPSLE group; the commonest was seizure disorders (43.3%), followed by psychosis (20.0%), cerebrovascular disease (16.7%), acute confusional state (13.3%), headache (10.0%) and lastly demyelinating syndrome (6.7%). SLEDAI score was higher in NPSLE group (Median=16) than nonNPSLE group (Median=4) (P < 0.01). ACL IgM positivity was higher in NPSLE group (P < 0.05). 53.3% of NPSLE group had abnormal MRI brain findings, the most common finding was periventricular white matter lesion (23.3%), followed by infarction (13.3%), subcortical white matter lesion and demyelinating lesion (6.7%). Lastly was sinus thrombosis, cerebral edema and encephalomalacia (3.3% each). 12 patients out of 30 (40.0%) with NPSLE had EEG abnormalities, while all 30 patients with non-NPSLE had no EEG abnormalities. The most common EEG abnormalities in NPSLE group were diffuse slowing (20.0%), followed by generalized epileptiform activity (13.3%), and lastly temporal epileptiform activity (6.7% each). 50% of patients with abnormal EEG had normal MRI. 13 patients out of 30 with NPSLE had seizure disorders (43.3%), 8 of them had abnormal EEG (61.5%). Conclusion Not all patients with NPSLE must have abnormal brain MRI or EEG. EEG is a useful assistant tool in diagnosing and studying the different manifestations of NPSLE especially seizure disorder and acute confusional state, but it cannot be used as a screening test alone for detecting NPSLE and must be supplemented by neuroimaging studies.