A Case of Anti-Hu Antibody-Associated Sensory Neuronopathy after Subacute Combined Degeneration of the Spinal Cord

Abstract

Abstract Introduction: Paraneoplastic neurological syndromes (PNS) are non-metastatic complications of malignancy that result from immune-mediated neuronal dysfunction or death and can affect any part of the nervous system. Hu, Yo, Ri and other antibodies are involved in nervous system injury. PNS is rare in the clinic, among which sensory neuronopathy (SNN) is one of the few classic syndromes, and the report of the pyramidal tract sign is rare. Here we report a case of SNN associated with bilateral pyramidal tract impairment. The patient's main complaint is numbness in the limbs and face. Even after early diagnosis of subacute combined degeneration of the spinal cord (SCD) and active treatment, the numbness symptoms continue to worsen. The patient's diagnosis was finally confirmed after parathyroid-related antibody testing. The patient was finally diagnosed with probable PNS but no tumor has been found for 8 years since the onset of the disease. So she has not received any immunomodulatory or immunosuppressive treatment. It is recommended that the patient continue to take vitamin B and undergo tumor screening every 6 months. Conclusion: The early SCD of this case masked its true cause, and there are many unique aspects to this case: despite a long medical history, no tumors were found; concurrent bilateral pyramidal tract sign; NCV examination showed predominantly peripheral sensory axonal damage. Therefore, it has brought difficulties to the diagnosis of our cases and provided ideas for the diagnosis of similar cases in the future.