A neurological puzzle: Adult-onset non-epileptic seizures in Sturge-Weber syndrome

Dear Editor, We report a case of a 46-year-old female with purple discoloration on the left side of her face since birth and diminished vision in the left eye [Figure 1]. She experienced Generalized tonic–clonic seizure (GTCS)-type seizures for 1 year, with no history of seizures, developmental delay, or stroke-like episodes in childhood. Brain magnetic resonance imaging (MRI) revealed mild left cerebral hemisphere atrophy, prominent choroid plexus in the left lateral ventricle, and possible choroidal hemangioma, findings suggestive of Sturge-Weber Syndrome (SWS) [Figure 2]. She was started on carbamazepine (400 mg/day), later increased, and levetiracetam (up to 1500 mg/day) was added. Due to poor seizure control and atypical features, Electroencephalography (EEG) telemetry was planned.Figure 1: Purple discoloration of the left side of the faceFigure 2: (a) Shows T1 weighted image left hemisphere atrophy. (b) shows T2 weighted image shows small enhancing leptomeningeal angioma left occipital lobe. (c) shows FLAIR image and (d) shows T1 weighted post contrast image shows bulky and hyperenhancing left choroid plexus with prominent ipsilateral deep cerebral veins. Findings consistent with Sturge Weber syndromeDuring a 48-hour EEG monitoring, the patient had one typical episode. Interictal EEG showed normal awake background activity (7–8 Hz, 20–30 µV), reactive to eye opening, with no focal or generalized discharges. A spontaneous event occurred while awake, featuring vocalization, clonic jaw movements, limb thrashing, and eye closure, lasting 15 min. She was unresponsive during the event, followed by right-sided weakness (UL > LL), shoulder pain, and transient speech loss, though she responded to commands. EEG showed no changes, confirming both recorded events as non-epileptic. Psychiatric evaluation revealed low self-esteem, social withdrawal, poor interpersonal relationships, and past depressive episodes. She was started on antidepressants, benzodiazepines, and cognitive behavioral therapy, which reduced episode frequency. Subsequently, she developed headache and eye pain. OCT-RNFL revealed increased cup-to-disc ratio and retinal nerve fiber layer thinning in the left eye, suggestive of unilateral glaucoma [Figure 3]. She was started on Brinzolamide eye drops after ophthalmology consultation.Figure 3: (a) Optical Coherence Tomography (OCT) performed in September 2021. (b) OCT shows bilateral retinal nerve layer thinning, left eye > right eye, performed in April 2022, as compared to September 2021SWS is a rare, sporadic congenital disorder involving vascular malformations of the skin, brain, and eyes. It typically presents with a facial port-wine stain (nevus flammeus), leptomeningeal angiomatosis, and glaucoma. The incidence is about 1 in 20,000–50,000 live births, with no gender or race preference.[1,2] SWS is caused by a somatic activating mutation in the GNAQ gene, leading to abnormal vascular development, endothelial dysfunction, and capillary malformations. Brain imaging may show “tram-track” calcifications. Neurological symptoms include seizures, developmental delay, and stroke-like episodes. Glaucoma results from increased intraocular pressure due to vascular anomalies.[3] In SWS, neurological impairments, visible facial hemangiomas, and the disorder’s chronic nature contribute to a higher risk of psychiatric conditions. Reported manifestations include mood disorders, behavioral issues such as impulsivity, aggression, and ADHD, especially in children. These often stem from disfigurement or neurological complications. NES, which resemble epileptic seizures but lack EEG abnormalities, are another psychiatric feature. NES may present as unresponsiveness, tremors, or altered awareness, often triggered by psychological stress or trauma, as seen in our case. Turin et al. (2010) highlighted the under-recognized yet significant impact of such symptoms on quality of life.[4] This unique case of SWS presenting with NES highlights the importance of distinguishing NES from epilepsy, as both may co-exist and require different treatments.[5,6] Psychiatric aspects of SWS are often under-recognized, with no similar cases reported in the literature. NES in SWS reflects the complex neurological and psychological interplay of the disorder. Early recognition is crucial to avoid unnecessary medications, reduce healthcare burden, and improve quality of life, especially in young patients. Hence a strong suspicion of alternative diagnosis shall be considered if patient does not respond to medications. NES may lack stereotyped patterns or postictal confusion typical of epileptic seizures. Video-EEG Monitoring helps in differentiating and diagnosing NES from epileptic seizures by showing a lack of ictal EEG activity during episodes. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the legal guardian has given his consent for images and other clinical information to be reported in the journal. The guardian understands that names and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.