Acanthamoeba and the blood-brain barrier: the breakthrough.

Acanthamoeba granulomatous encephalitis is a rare disease that almost always proves fatal. Death occurs mainly due to neurological complications; however, the pathogenesis and pathophysiology associated with this disease remain incompletely understood. Haematogenous spread is a key step in the development of Acanthamoeba encephalitis, but it is not clear how circulating amoebae breakthrough the blood-brain barrier to gain entry into the central nervous system to produce the disease. This review of the literature describes the parasite factors and immune-mediated mechanisms involved in the blood-brain barrier dysfunction leading to neuropathogenesis.