AUTOIMMUNE CNS DISORDERS

Time of India

05-05-2025

Autoimmune Central Nervous System (CNS) disorders develop when the body's immune system mistakenly attacks its healthy brain cells/ neurons, leading to inflammation of the brain. This may be associated with antibodies to proteins located either on the surface of nerve cells or within nerve cells.
Antibody-mediated CNS disorders
are increasingly recognized as neurologic disorders that can be severe and even life-threatening but with the potential for reversibility with appropriate treatment.
The expanding spectrum of newly identified autoantibodies and associated clinical syndromes (ranging from autoimmune encephalitis to
CNS demyelination
) has increased diagnostic precision and allowed critical reinterpretation of non-specific neurological syndromes historically associated with systemic disorders.
Detection of
neural autoantibodies
with accurate laboratory assays in patients with compatible clinical-MRI phenotypes allows a definite diagnosis of antibody-mediated CNS disorders, with important therapeutic and prognostic implications.
A large spectrum of diseases is covered in these disorders depending on the target site against which Antibodies develop. These include Limbic encephalitis, Morvan syndrome, Facio-brachial dystonic seizures, Opsoclonus-myoclonus syndrome, Demyelinating Syndromes, Acute disseminated encephalomyelitis, Optic neuritis, anti-MOG-associated encephalitis – to name the few.
Other autoimmune syndromes may be associated with various cancers.
This group of conditions may have various neurologic and/or psychiatric symptoms. Symptoms may start with psychiatric manifestations followed by neurological.Psychiatric symptoms may include psychosis, aggression, inappropriate sexual behaviours, panic attacks, compulsive behaviours, euphoria, or fear.
The disorders may start with flu-like conditions & develop further into neurological manifestations. Neurologic symptoms may include impaired memory and cognition, abnormal movements, seizures, and/or problems with balance, speech, or vision.
There are two major requirements for a correct diagnosis of antibody-mediated CNS disorder to be made:
(1)a reliable identification of one or more specific neural autoantibodies; and (2)a compatible clinical-MRI phenotype.
Over the years, there has been an ongoing discovery of newer antibodies against various proteins. NMDA, LG -i1, CASPR-2, AMPA, GABA A, GABA B, GAD65 DPPx, IGNOL-5 causing Limbic encephalitis.AQP4 antibodies and MOG autoantibodies cause Optic neuritis, Acute disseminated encephalomyelitis & Myelitis lesions. Certain neural autoantibodies are strongly associated with specific types of cancer.
Sophisticated technology which includes Neural Autoantibody Testing by Indirect Cell-Based Immunofluorescence assay, immunoblot assay, ELISA, and Cell cultures allows for accurate laboratory diagnosis. These tests can be performed on Blood & CSF (cerebrospinal fluid).
Although
autoimmune CNS disorders
are often treatment-responsive, they can lead to serious complications if left untreated or if there is a delay in treatment. Timely diagnosis and treatment, therefore, becomes important to avoid complications of the disease.
Treatment may include
Immunotherapy
(e.g., plasmapheresis, intravenous Immunoglobulin, and corticosteroids) and tumour resection if the disease is associated with the tumour.
Patient education is necessary to understand the etiology, acute and chronic clinical progression of the condition, and its probable association with underlying malignancy.
They should be educated about the variable course of the disease, which may lead to a delay in diagnosis. Furthermore, patients should be encouraged to follow up after hospital discharge with their respective neurologist /oncologist due to concerns about relapse and screening for malignancy.
This article is written by Dr. Geeta Chopra, Chief of Lab – North India Operations, Metropolis Healthcare Limited.
(DISCLAIMER: The views expressed are solely of the author and ETHealthworld.com does not necessarily subscribe to it. ETHealthworld.com shall not be responsible for any damage caused to any person/organisation directly or indirectly)