Treatment and prognosis of brain abscess

INTRODUCTION

Brain abscess is a focal collection within the brain parenchyma, which can arise as a complication of a variety of infections, trauma, or surgery. Successful treatment of a brain abscess requires a high index of suspicion for the infection, which can have subtle presentations, and frequently requires a combination of drainage and antimicrobial therapy. A summary of key steps in management is provided in Table 1 (table 1).

The treatment and prognosis of brain abscess will be presented here. The pathogenesis, clinical manifestations, and diagnosis of this disease are discussed separately. (See "Pathogenesis, clinical manifestations, and diagnosis of brain abscess".)

THERAPY

Successful management of a brain abscess usually requires a combination of antibiotics and surgical drainage for both diagnostic and therapeutic purposes [1-3].

Antibiotics — A number of drugs can be chosen depending upon the likely origin of the abscess and the probable pathogen(s) involved. These antibiotics include:

• Penicillin G covers most mouth flora including both aerobic and anaerobic streptococci. However, the emergence of penicillinase-producing anaerobes (eg, B. fragilis, Prevotella) is a potential limitation of penicillin therapy.
• Metronidazole readily penetrates brain abscesses; intralesional concentrations have been found to be 40 microgram/mL. This drug has excellent bactericidal activity against many anaerobes but is not active against aerobic organisms including microaerophilic streptococci. Given the excellent intralesional concentrations and the high probability of anaerobes, many experts recommend administering this agent to most patients with brain abscess.
• Ceftriaxone covers most aerobic and microaerophilic streptococci (and can be used in place of penicillin) but also covers many Enterobacteriaceae as well, which can cause brain abscess particularly in association with chronic ear or sinus infections or following penetrating trauma. Cefotaxime provides similar coverage.
• Ceftazidime or cefepime should be used when brain abscess complicates a neurosurgical procedure or in cases in which the abscess culture grows P. aeruginosa.
• Oxacillin, nafcillin, or vancomycin should be included when brain abscess follows penetrating head trauma or craniotomy, or when S. aureus bacteremia is documented. Vancomycin should be particularly considered for post-neurosurgery patients, in hospital-associated infections, and in communities where community-associated methicillin-resistant S. aureus is common until culture and susceptibility results are available.