Consensus Paper: Latent Autoimmune Cerebellar Ataxia (LACA)

Area of Science:

• Neurology
• Immunology
• Endocrinology

Background:

• Immune-mediated cerebellar ataxias (IMCAs) present with gait ataxia and acute/subacute onset.
• Latent autoimmune diabetes in adults (LADA) is a slowly progressive autoimmune diabetes.
• LADA patients are often misdiagnosed with type 2 diabetes, with fluctuating or absent biomarkers.

Purpose of the Study:

• Introduce the concept of Latent Autoimmune Cerebellar Ataxia (LACA).
• Highlight diagnostic challenges in early-stage IMCAs.
• Emphasize the critical window for intervention before irreversible neuronal loss.

Main Methods:

• Conceptual framework based on LADA analogy.
• Discussion of two LACA aspects: subtle autoimmunity and prodromal neuronal dysfunction.
• Emphasis on identifying biomarkers for early detection.

Main Results:

• LACA is characterized by slow progression, subtle autoimmune features, and diagnostic difficulties.
• A prodromal stage of IMCA involves partial neuronal dysfunction with non-specific symptoms.
• LACA represents a critical window for intervention during partial neuronal dysfunction.

Conclusions:

• Early identification of LACA is vital for timely therapeutic intervention.
• Multimodal biomarkers (biological, neurophysiological, neuropsychological, morphological) are needed for early LACA diagnosis.
• Intervention during the LACA phase can prevent irreversible cerebellar damage and preserve neural plasticity.