Related Experiment Video
Updated: May 17, 2026

Intracranial Subarachnoidal Route of Infection for Investigating Roles of Streptococcus suis Biofilms in Meningitis in a Mouse Infection Model
Published on: July 1, 2018
Inflammatory index and treatment of brain abscess
Hirofumi Oyama1, Akira Kito, Hideki Maki
1Department of Neurosurgery, Ogaki Municipal Hospital, Ogaki 503-8502, Japan. oya3776@arrow.ocn.ne.jp
Abstract:
This study retrospectively analyzed 12 patients with brain abscesses. Half of the patients were diagnosed inaccurately in the initial stage, and 7.2 days were required to achieve the final diagnosis of brain abscess. The patients presented only with a moderately elevated leukocyte count, serum CRP levels, or body temperatures during the initial stage. These markers changed, first with an increase in the leukocyte count, followed by the CRP and body temperature. The degree of elevation tended to be less prominent, and the time for each inflammatory index to reach its maximum value tended to be longer in the patients without ventriculitis than in those with it. The causative organisms of a brain abscess were detected in 10 cases. The primary causative organisms from dental caries were Streptococcus viridians or milleri, and Fusobacterium nucleatum. Nocardia sp. or farcinica were common when the abscess was found in other regions. The primary causative organisms of unrecognized sources of infection were Streptococcus milleri and Prolionibacterium sp. Nocardia is resistant to many antibiotics. However, carbapenem, tetracycline and quinolone were effective for Nocardia as well as many other kinds of bacteria. In summary, the brain abscesses presented with only mildly elevated inflammatory markers of body temperature, leukocyte and CRP. These inflammatory markers were less obvious in the patients without ventriculitis and/or meningitis. The source of infection tended to suggest some specific primary causative organism. It was reasonable to initiate therapy with carbapenem.
Insights
Brain abscesses often present with subtle inflammatory markers, delaying diagnosis. Early carbapenem therapy is recommended due to common causative organisms and their antibiotic sensitivities.
Area of Science:
- Neurology
- Infectious Diseases
- Microbiology
Background:
- Brain abscesses are serious infections requiring timely diagnosis and treatment.
- Initial symptoms can be non-specific, leading to diagnostic delays.
Purpose of the Study:
- To analyze diagnostic challenges and clinical features of brain abscesses.
- To identify common causative organisms and evaluate antibiotic efficacy.
Main Methods:
- Retrospective analysis of 12 brain abscess patient cases.
- Review of clinical data, inflammatory markers, and microbiological findings.
Main Results:
- Delayed diagnosis (average 7.2 days) due to mild inflammatory markers (leukocyte count, CRP, body temperature).
- Inflammatory markers were less pronounced in patients without ventriculitis/meningitis.
- Common pathogens identified, including Streptococcus, Fusobacterium, and Nocardia species.
- Carbapenem, tetracycline, and quinolone showed effectiveness against Nocardia and other bacteria.
Conclusions:
- Brain abscesses may present with subtle inflammatory signs, complicating early diagnosis.
- Infection source can indicate specific causative organisms.
- Empirical therapy with carbapenem is a reasonable starting point.
Related Concept Videos
Brain Abscess l: Introduction
Bacterial Meningitis II: Pathophysiology
Bacterial Meningitis I: Introduction
Acute Pyelonephritis II: Diagnostic Studies and Management
Acute Inflammation III: Local and Systemic Effects

