Clinical and radiological characteristics of brain abscess due to different organisms in hospitalized patients: A 6-year retrospective study from China

Brain abscess (BA) is a rare but life-threatening infection. Early identification of the pathogen is helpful to improve the outcomes. This study aimed to describe the clinical and radiological features of patients with BA caused by different organisms. A retrospective, observational study of patients with known etiologic diagnosis of BA in Huashan Hospital Affiliated to Fudan University in China between January 2015 and December 2020 was conducted. Data on patient demographics, clinical and radiological presenting features, microbiological results, surgical treatment, and outcomes were collected. Sixty-five patients (49 male, 16 female) with primary BAs were included. Frequent clinical presentations included headache (64.6%), fever (49.2%) and confusion (27.3%). Streptococcus viridans was associated with thicker wall of abscesses (6.94 ± 8.43 mm for S. viridans versus 3.66 ± 1.74 mm for other organisms, P = 0.031) and larger oedema (89.40 ± 15.70 mm for S. viridans versus 74.72 ± 19.70 mm for other organisms, P = 0.023). The independent factor associated with poor outcome identified by multivariate analysis was confusion (Odds ratio 6.215, 95% confidence interval 1.406–27.466; P = 0.016). Patients with BAs caused by Streptococcus species had nonspecific clinical signs, but specific radiological features, which might be helpful for early diagnosis.