Unexpected plasmablastic lymphoma in a young adult with unknown HIV infection: case report.

Background: Plasmablastic lymphoma (PBL) is a rare, highly aggressive lymphoma of plasma cell differentiation. It commonly presents as an Epstein-Barr virus (EBV)+ oral lesion in an immunodeficient patient, predominately human immunodeficiency virus (HIV)+ patients. These aggressive lesions often demonstrate an immunoblastic or plasmablastic morphology with a typical immunohistochemical profile. The current case is unique due to the location at presentation, immunohistochemical features, and unknown presence of HIV infection in a young adult male. Case Presentation: We present an unexpected case of PBL found in a rare extra-oral location in a young adult male with undiagnosed HIV infection presenting as a perianal hemorrhoid mass/abscess. Swift treatment for HIV and the PBL resulted in complete remission and markedly improved CD4 counts. Conclusions: This case highlights the importance of testing for HIV along with acquiring a thorough social/clinical history when a PBL is encountered. Although the overall prognosis of PBL is dismal with a median survival of about 6-11 months, a timely accurate diagnosis and prompt chemotherapy with an appropriate regimen along with antiretroviral therapy (ART) may still achieve a successful outcome with a relatively reasonable long-term remission like in our reported case.

Glutamate metabolism in temporal lobe epilepsy as revealed by dynamic proton MRS following the infusion of [U13-C] glucose.

Focal metabolic dysfunction commonly observed in temporal lobe epilepsy (TLE), and is associated with the development of medical intractability and neurocognitive deficits. It has not been established if this dysfunction is due to cell loss or biochemical dysfunction in metabolic pathways. To explore this question, dynamic 1H MRS following an infusion of [U13- C] glucose was performed to measure glutamate (Glu) metabolism. Subjects (n=6) showed reduced Glu levels (p<0.01) in the ipsilateral mesial temporal lobe (MTL) compared with controls (n=4). However, the rate of 13C incorporation into Glu did not differ between those with epilepsy and controls (p=0.77). This suggests that reduced Glu concentrations in the region of the seizure focus are not due to disruptions in metabolic pathways, but may instead be due to neuronal loss or simplification.