Systemic Lupus Erythematosus (SLE), often called lupus, is a chronic autoimmune disorder where the body’s immune system mistakenly attacks its own healthy tissues and organs. This systemic inflammation commonly affects the joints, skin, and kidneys, leading to symptoms like joint pain, rashes, and kidney problems. Because lupus can affect any organ, it can involve the nervous system and the brain, raising the possibility of neurological events like seizures.
Understanding Seizures as a Lupus Symptom
Lupus can directly cause seizures, which are considered one of the major neurological complications of the disease. Studies suggest that a single seizure occurs in approximately 10% to 20% of individuals with SLE at some point during their disease course. These episodes are most commonly seen during periods of high disease activity, known as flares, or shortly after the initial diagnosis. The most frequent type of seizure observed in lupus patients is the generalized tonic-clonic seizure, which affects both sides of the brain.
Lupus Affects the Central Nervous System
The involvement of the brain and spinal cord in lupus is formally categorized as Neuropsychiatric Systemic Lupus Erythematosus (NPSLE). Seizures are one of the many syndromes identified under NPSLE that result from the disease’s effects on the nervous system. The brain is a target organ in lupus, meaning the immune system’s attack can lead to a wide variety of neurological and psychiatric symptoms. The spectrum of NPSLE is broad. Other frequently reported manifestations include severe headaches, cognitive dysfunction (often described as “brain fog”), and mood disorders like anxiety and depression. Psychosis and stroke are also recognized consequences of CNS involvement in SLE.
Biological Causes of Seizure Activity
The mechanisms by which lupus triggers a seizure are complex, involving a combination of inflammation and blood vessel problems within the brain. One primary cause is direct inflammation of the brain tissue, known as cerebritis, driven by the autoimmune response. Pro-inflammatory signaling molecules, such as cytokines, are elevated during lupus flares and can lower the threshold at which brain cells fire, making a seizure more likely.
A compromised blood-brain barrier permits autoantibodies to cross into the central nervous system, where they attack neurons and disrupt normal electrical signaling pathways. The disease can also affect the brain’s blood supply through vasculitis, which is the inflammation of blood vessel walls.
Another significant pathway involves antiphospholipid antibodies, often present in lupus patients. These antibodies promote the formation of blood clots (thrombosis), leading to small strokes or areas of reduced blood flow (ischemia) in the brain. Localized brain damage from these thrombotic events can create a focal point for the abnormal electrical activity that defines a seizure.
Diagnosis and Management
Diagnosing a lupus-related seizure requires a comprehensive evaluation to rule out other causes, such as infection, high blood pressure, or metabolic abnormalities. Physicians use a combination of diagnostic tools to confirm the cause and rule out other possibilities.
Diagnosis
Brain imaging, such as Magnetic Resonance Imaging (MRI) or Computed Tomography (CT) scans, can reveal signs of inflammation, stroke, or bleeding. An electroencephalogram (EEG) is performed to record the brain’s electrical activity and identify abnormal patterns characteristic of a seizure disorder. In some cases, a lumbar puncture (spinal tap) is necessary to analyze the cerebrospinal fluid for signs of inflammation or infection within the central nervous system.
Management
Treatment for a lupus-related seizure follows a two-part strategy: controlling the seizure and managing the underlying lupus activity. Anticonvulsant medications are used to suppress the abnormal electrical activity and prevent future seizures. Simultaneously, high-dose immunosuppressive therapy, often involving corticosteroids, is administered to reduce the inflammation and autoimmune attack that caused the event. Promptly reporting any new neurological symptoms is important for patients with lupus, as early intervention to control the underlying disease activity is the most effective way to manage and reduce the risk of future seizures.