Isolated Abducens Palsy Heralding Occult Human Immunodeficiency Virus-Related Lymphoma.

A 40-year-old African American man with recently diagnosed Human Immunodeficiency Virus (HIV) presented with isolated left abducens palsy. Initial neuro-imaging and laboratory evaluation, including cerebrospinal fluid (CSF) analysis, were unremarkable. Continued search for causative aetiology revealed systemic lymphoma diagnosed ultimately by bone marrow biopsy. Systemic lymphoma is commonly encountered in the HIV patient population, but presentation can be unusual and has been seen, albeit rarely, in the setting of isolated cranial neuropathy. This case demonstrates the often diligent investigation required in the setting of isolated cranial neuropathies in patients with HIV.