A 38-year-old woman presenting with slowly progressive diabetes is suspected to have latent autoimmune diabetes of adults (LADA). Which antibody has the highest sensitivity for confirming autoimmune beta-cell destruction in adult-onset disease?

• A Anti-insulin antibody (IAA)
• B Anti-ZnT8 transporter antibody
• C Anti-IA-2 (islet antigen-2) antibody
• D Anti-GAD65 antibody ✓

Explanation

Antibodies against glutamic acid decarboxylase 65 (GAD65) are the most frequently detected islet autoantibody in adult-onset autoimmune diabetes and persist for years, making them the marker of choice for LADA. IA-2 and ZnT8 antibodies appear mainly in acute childhood-onset type 1 diabetes, and insulin autoantibodies are least useful once exogenous insulin therapy has begun, since they lose specificity.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.