Brain Involvement in Leishmaniasis

Leishmaniasis is a neglected tropical disease caused by infection with the protozoan parasite Leishmania and it is a significant global health problem. The disease has a wide clinical spectrum, from tegumentary leishmaniasis (TL) that encompasses cutaneous (CL), mucosal (ML) and cutaneous-diffuse (CDL) forms, to the potentially fatal systemic visceral leishmaniasis (VL). Neurological manifestations are not generally considered as classical clinical signs or symptoms of leishmaniasis, but in this review, we present evidence that this is a false assumption. We examine brain involvement in human and canine leishmaniasis and the contribution of animal models for studying cerebral Leishmania infection. Clinical descriptions of brain involvement are presented, and evidence of Leishmania invasion of the central nervous system. Notably, evidence for brain involvement comes from considerable studies in the dog and covers aspects of disruption of the blood-brain and blood-cerebrospinal fluid barriers and the nature of the inflammatory response.