An unusual presentation of anti-Hu-associated paraneoplastic limbic encephalitis

Paraneoplastic limbic encephalitis is a rare disorder characterized by personality changes, seizures, memory loss, and psychiatric symptoms often associated with antineuronal antibodies. It is well described in the adult literature but is still underreported in the pediatric literature. Symptoms are usually multifocal and subacute in presentation, occurring over days to weeks; however, in rare cases, symptom onset can be more gradual. We report the case of a 9-year-old male with anti-Hu-associated paraneoplastic limbic encephalitis that presented as episodic ataxia and behavioral changes evolving to intractable epilepsy and worsening behavioral changes over the course of a year. This case highlights the importance of considering a paraneoplastic disorder in the differential diagnosis for unexplained multifocal neurological symptoms of subacute or chronic onset as earlier detection and treatment may result in an improved outcome.