CD8 T lymphocytes encephalitis mimicking brain tumor in HIV-1 infection

Abstract

Combined antiretroviral therapy (cART) has led to considerable improvement in the spectrum of disorders affecting the central nervous system (CNS). The majority of focal brain presentations are due to toxoplasmosis, non-Hodgkin's lymphoma, and progressive multifocal leukoencephalopathy. Other causes are much rarer (Moulignier et al. 1994, 1996; Saravanan and Turnbull 2009). A growing number of severe, acute inflammatory leukoencephalopathies, whose causes remain to be identified, have been recently reported (Tavazzi et al. 2010). These include highly destructive forms of HIVassociated leukoencephalopathy (Langford et al. 2002), “burnt out” forms of HIV encephalitis (Scaravilli et al. 2007), immune reconstitution inflammatory syndrome (IRIS) (Venkataramana et al. 2006), brain tumefactive demyelination (Saravanan and Turnbull 2009; Solomon et al. 2013), and discordant HIV diseases (Canestri et al. 2010). A series of cases of diffuse encephalitis with marked perivascular infiltration by CD8 T lymphocytes with corticosteroid-responsive brain inflammation have been described as CD8 encephalitis (Lescure et al. 2013; Gray et al. 2013). Brain MRI shows characteristic perivascular punctuate or linear gadolinium-enhanced lesions, better seen in T1 spin echo with magnetic transfer, that are poorly delineated in T2weighted images (Lescure et al. 2013). We describe the first biopsy-proven focal CD8 encephalitis (CD8-E) mimicking a brain tumor in a HIV+ patient.