Brain abscess
Brain abscesses are suppurative infections of the brain parenchyma surrounded by a vascularized capsule.
Classification
Non Traumatic brain abscess
The most frequent intracranial locations (in descending order of frequency) are: frontal-temporal, frontal-parietal, parietal, cerebellar, and occipital lobes.
Epidemiology
In a article, Chen review the literature to find out how the epidemiology of this disease has changed through the years and re-visit the basic pathological process of abscess evolution and highlight the new research in the biochemical pathways that initiate and regulate this process 1).
The epidemiology of brain abscess has changed with the increasing incidence of this infection in immunocompromised patients, particularly solid organ and bone marrow transplant recipients, and the decreasing incidence of brain abscess related to sinusitis and otitis 2).
There have been several trends in the epidemiology of brain abscess over recent decades. One trend is that there appears to be a trend toward a decreasing incidence of brain abscess. In a population-based study of residents of Olmstead County, Minnesota, the incidence rate was 1.3 per 100,000 patient-years from 1935 to 1944 compared with 0.9 per 100,000 patient-years from 1965 to 1981 3).
Etiology
Clinical features
Similar to any other mass lesion but tend to progress rapidly.
Abscess formation should be considered in case of clinical deterioration, headache, and any neurological deficit after febrile episodes.
Diagnosis
Differential diagnosis
see Brain abscess differential diagnosis.
Complications
Intraventricular rupture of brain abscess (IVROBA)
Strongly influences poor outcome in patients with cyanotic heart disease. The key to decreasing poor outcomes may be the prevention and management of IVROBA. To reduce operative and anesthetic risk in these patients, abscesses should be managed by less invasive aspiration methods guided by computed tomography. Abscesses larger than 2 cm in diameter, in deep-located or parieto-occipital regions, should be aspirated immediately and repeatedly, mainly using computed tomography-guided methods to decrease intracranial pressure and avoid IVROBA. IVROBA should be aggressively treated by aspiration methods for the abscess coupled with the appropriate intravenous and intrathecal administration of antibiotics while evaluating intracranial pressure pathophysiology 4).
Treatment
Management
Outcome
Significant advances in the diagnosis and management of bacterial brain abscess over the past several decades have improved the expected outcome of a disease once regarded as invariably fatal. Despite this, intraparenchymal abscess continues to present a serious and potentially life-threatening condition 5).
There has been a gradual improvement in the outcome of patients with brain abscess over the past 50 years, which might be driven by improved brain imaging techniques, minimally invasive neurosurgical procedures, and protocoled antibiotic treatment. Multicenter prospective studies and randomized clinical trials are needed to further advance treatment and prognosis in brain abscess patients.
Our understanding of brain abscesses has increased by meta-analysis on clinical characteristics, ancillary investigations, and treatment modalities. Prognosis has improved over time, likely due to improved brain imaging techniques, minimally invasive neurosurgical procedures, and protocoled antibiotic treatment 6).
Current evidences suggest that for encapsulated brain abscess in superficial non-eloquent area, abscess resection compared to abscess aspiration had lower post-operative residual abscess rate; lower re-operation rate; higher rate of improvement in neurological status within 1 month after surgery, shorter duration of post-operative antibiotics and average length of hospital stay. There was no statistically significant difference in the rate of improvement in neurological status at 3 months post-operative and the mortality 7).
Case series
Case reports
see Brain abscess case reports.
Books
see Brain abscess books.