Background: Psychiatric disorders are often difficult to evaluate and sometimes have negative connotations associated. That could be a reason to ignore the correct diagnosis of underlying neurological diseases.Case report: We present a case report of a patient with psychiatric symptomatology, where during the study in the Emergency Department an acute hydrocephalus secondary to a massive meningioma was evidenced.Conclusions: This case exemplifies how psychiatric symptoms, often devalued by the physician, may be the first manifestation of serious neurological disorders, as well as being associated with a medical emergency, as in this case was the acute hydrocephalus.