A 45-year-old woman with ovarian adenocarcinoma develops cerebellar ataxia. Serum anti-Yo (anti-Purkinje cell) antibodies are detected. The pathological target of these antibodies in paraneoplastic cerebellar degeneration is:

• A Basket cell axons
• B Granule cell layer neurons
• C Cerebellar Purkinje cells ✓
• D Deep cerebellar nuclei

Explanation

Anti-Yo antibodies target CDR2 and CDR2L proteins expressed on Purkinje cells and, ectopically, on tumour cells. The immune attack on Purkinje cells leads to their selective degeneration, producing a rapidly progressive pancerebellar ataxia. This is the classic paraneoplastic cerebellar degeneration associated with ovarian and breast carcinomas. Granule cells and deep nuclei are not the primary target.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.