Chapter 5 - Brain abscess

Abstract

This chapter discusses the epidemiology, etiology, pathogenesis, clinical features, diagnosis, and management of brain abscess. Brain abscess is a focal area of purulent exudate surrounded by a well-developed capsule in the brain parenchyma. Case series reviewing all causes of bacterial abscess report Streptococcus spp. as the most commonly isolated organisms from abscess material, blood cultures, or both. An abscess arises as an inflammatory response to a local infection of the brain, called “cerebritis.” The infection begins after inoculation of the brain, which requires breakdown of the blood–brain barrier. The clinical presentation of a patient with a brain abscess varies greatly depending on the size, location, and number of abscesses. While a minority of patients will have focal neurological deficits, the majority of signs and symptoms are nonspecific. Because the clinical features of patients with brain abscess are nonspecific, diagnosis is made primarily with neuroimaging. Magnetic resonance spectroscopy may be helpful in confirming a diagnosis of brain abscess. Though imaging techniques greatly aid in the diagnosis of bacterial brain abscesses, definitive diagnosis can be made only with a biopsy.