Isolated cranial nerve III palsy as the presenting manifestation of HIV-related large B-cell lymphoma: clinical, radiological and postmortem observations: report of a case and review of the literature.

Rarely can a neurologically isolated cranial nerve III palsy be the presenting manifestation of central nervous system lymphoma. We detail the clinical, radiological, and pathological features of a previously healthy 45-year-old man presenting with an isolated, pupil-involving, right cranial nerve III palsy due to human immunodefiency virus (HIV) related non-Hodgkin lymphoma. Magnetic resonance imaging demonstrated bilateral peripheral cranial nerve III enhancement with no brain parenchymal or leptomeningeal abnormalities. Cerebrospinal fluid analysis revealed a monocytic pleocytosis with an elevated protein concentration and depressed glucose level. Morphologic and flow cytometric analysis of the cerebrospinal fluid was compatible with a large B-cell lymphoma. Serologic tests for HIV were positive. Postmortem examination of the brain revealed malignant lymphomatous cell infiltration of both cranial nerve III, diffuse leptomeningeal disease and focal superficial subependymal and subpial invasion. Based on our review of the literature, we were able to find only 10 detailed cases of cranial nerve III palsy as the presenting manifestation of central nervous system lymphoma. Furthermore, none of the previously reported cases correlated the magnetic resonance imaging findings with the gross and histopathologic observations.