A 54-year-old woman with breast carcinoma presents with progressive gait ataxia, dysarthria, and nystagmus. MRI of the brain is normal, CSF shows mild pleocytosis, and autopsy would be expected to show Purkinje cell loss. The antibody most characteristically associated with this presentation targets:
- A Yo (CDR, cytoplasmic Purkinje cell antigen) ✓
- B Hu (ANNA-1, neuronal nuclear antigen)
- C Voltage-gated calcium channel
- D NMDA receptor
Correct answer: A. Yo (CDR, cytoplasmic Purkinje cell antigen)
Explanation
Paraneoplastic cerebellar degeneration with gait ataxia, dysarthria, and nystagmus, accompanied by anti-Yo antibodies directed against cytoplasmic CDR antigens of Purkinje cells, occurs most often with breast and gynecologic malignancies. Anti-Hu produces encephalomyelitis and sensory neuropathy with small cell lung cancer, voltage-gated calcium channel antibodies produce Lambert-Eaton myasthenic syndrome, and anti-NMDA receptor encephalitis is linked to ovarian teratoma in young women. Each antibody defines a distinct clinicopathologic syndrome.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.