Differential Diagnosis for Elevated Immunoglobulin A and Concern for Neurological Disease
Single Most Likely Diagnosis
- Multiple Sclerosis: Elevated immunoglobulin A (IgA) can be seen in multiple sclerosis, particularly in the cerebrospinal fluid, which may indicate an abnormal immune response contributing to the disease's pathophysiology.
Other Likely Diagnoses
- Chronic Inflammatory Demyelinating Polyneuropathy (CIDP): This condition involves immune-mediated damage to the peripheral nerves and can present with elevated IgA levels, reflecting an underlying inflammatory process.
- Neurosarcoidosis: Although more commonly associated with elevated IgG, some cases of neurosarcoidosis may show increased IgA levels, indicating a complex immune response in this granulomatous disease affecting the nervous system.
- Guillain-Barré Syndrome: An autoimmune disorder that can follow infections, Guillain-Barré Syndrome might show elevated IgA in some cases, particularly if there's a preceding infection that triggers an IgA response.
Do Not Miss Diagnoses
- Waldenström's Macroglobulinemia: A type of non-Hodgkin lymphoma characterized by the production of large amounts of IgM, but in rare cases, IgA can be elevated. Neurological symptoms can occur due to hyperviscosity syndrome or direct infiltration of the nervous system.
- Amyloidosis: Certain types of amyloidosis, particularly those associated with plasma cell dyscrasias, can present with neurological symptoms and elevated IgA levels due to the production of light chain amyloid proteins.
Rare Diagnoses
- IgA Nephropathy with Neurological Involvement: Although primarily a renal disease, IgA nephropathy can rarely be associated with neurological manifestations, possibly due to immune complex deposition or vasculitis affecting the nervous system.
- Multifocal Motor Neuropathy (MMN): A rare condition characterized by asymmetric muscle weakness, MMN can have elevated IgA or IgM antibodies against gangliosides, indicating an autoimmune pathogenesis.
- Paraproteinemic Neuropathies: These are rare neurological disorders associated with the production of abnormal proteins (paraproteins), including IgA, which can cause neuropathy through various mechanisms, including direct toxicity or immune-mediated damage.