Anaplasma phagocytophilum is an intracellular bacteria that causes several non-specific symptoms (for instance, horse lying down), posing problems in differential diagnosis. Usually, symptoms appear few days after tick exposure. Less often their neurological forms are observed to be correlated with visible neuroanatomical localization, with computed tomography (CT) or magnetic resonance (MRI). The aim of this paper is to present the review of a neurological form of EGA in a horse as well as localization of hypodense cerebral changes with the use of CT. This work also describes a case of a horse suffering from anaplasmosis confirmed by positive PCR results for Anaplasma phagocytophilum from peripheral blood and cerebrospinal fluid, four months after exposure to ticks. In 30% of such cases blood smear tests showed no evidence of bacteria. Hypodense lesions were observed in the CT scan of the brain and brainstem. As demonstrated by literature in humans, anaplasmosis can be considered in differential diagnosis as a potential cause of non-specific neurological symptoms, particularly in areas endemic for anaplasmosis, where animals are exposed to contact with ticks. Possible neurological complications in horses as a result of anaplasmosis have been reported but there are no reports on the identification and diagnosis of the brain in cerebral anaplasmosis by using CT or MRI imaging tools. So far, such a diagnostic procedure in the case of tick diseases has been identified in case of humans only.