Anti-Neuronal Nuclear antibodies test is used to help diagnose and manage paraneoplastic syndromes, such as sensory neuropathy and encephalomyelitis. This test screens for five antibodies – Anti-Hu, Anti-Yo (PCA1), Anti-PNMa2 (Ma/Ta), Anti-Ri (ANNA2) and Anti-amphiphysin.

Detection of Anti-Hu (ANNA1) antibody is diagnostically relevant in paraneoplastic syndromes; sensory neuronopathy, chronic gastrointestinal pseudoobstruction, cerebellar degeneration, and limbic encephalitis, and it is typically associated with small cell bronchial carcinoma, prostate carcinoma, or neuroblastoma.

Detection of Anti-Yo (PCA1) antibody is diagnostically relevant in paraneoplastic syndromes; opsoclonus myoclonus ataxia and cerebellar degeneration, and it is typically associated with breast or gynecological (endometrial, fallopian, ovarian) tumors.

Detection of Anti-PNMa2 (Ma/Ta) antibody is diagnostically relevant in paraneoplastic syndromes; limbic encephalitis, focal epilepsy, opsoclonus myoclonus ataxia, brainstem encephalitis, and cerebellar degeneration, and it is typically associated with seminoma or lung carcinoma.

Detection of Anti-Ri (ANNA2) antibody is diagnostically relevant in paraneoplastic syndromes; opsoclonus myoclonus ataxia and brainstem encephalitis, and it is typically associated with mammary carcinoma, small cell bronchial carcinoma or ovarian carcinoma. 

Detection of Anti-amphiphysin antibody is diagnostically relevant in paraneoplastic syndromes; Lambert Eaton myasthenia syndrome, cerebellar syndrome, sensoryneuronopathy, opsoclonus myoclonus ataxia, and Stiff-man syndrome, and it is typically associated with small cell bronchial carcinoma, breast cancer or Hodgkin’s disease.