Predictors of Treatment Failure in Patients With Pyogenic Brain Abscess

Pyogenic brain abscess poses a significant management challenge to clinicians, hence early diagnosis and interventions are critical. Our objective was to assess predictors of failure of therapy among patients with pyogenic brain abscesses according to surgical versus medical treatment.

Retrospectively reviewed adults with pyogenic brain abscesses at our institution between 2009 and 2020. Treatment was classified as early surgical intervention and no early surgical treatment (medical therapy). Propensity score (PS) adjustment and multivariable regression were used to assess risk of treatment failure from surgical intervention and baseline covariates.

A total of 224 patients had pyogenic brain abscess, of whom 106 (47.3%) had early surgical treatment and 118 (52.7%) had medical treatment only. Significant predictors of surgical (vs. medical) treatment included essential hypertension (odds ratio [OR] 95% confidence interval [95% CI] = 2.06 [1.01-4.18]), abscesses number (single vs. multiple, OR [95% CI] =4.81 [1.64-14.08]), midline shift (OR [95% CI] = 3.09 [1.22-7.82]). At 6 months, treatment failure cumulative incidence was 27.1% in the medical group (n = 31) and 21.3% in early surgical group (n = 22). PS-adjusted analysis showed beneficial effect of early surgical treatment (hazard ratio [HR] [95% CI] = 0.55 [0.31-0.98]). Multivariable regression showed similar but statistically nonsignificant estimate of surgical benefit (HR [95% CI] =0.59 [0.34-1.01]; P = 0.056), and significant associations of Charlson Comorbidity Index (CCI) (P = 0.019) and pre-existing central nervous system hardware (P = 0.034) with increased risk of treatment failure.

Higher CCI and pre-existing CNS hardware were significant risk factors associated with treatment failure. In propensity-adjusted analysis, early surgery was associated with a 45% reduction in risk of 6-month treatment failure.