Table 1.
Characteristics, predisposing factors and severity of illness in 430 patients with Staphylococcus aureus bacteremia (SAB) stratified according to 30-day mortality.
OR = odds ratio for fatal outcome. HR = hazard ratio for fatal outcome, 95% CI = 95% confidence interval. All values are given as number of patients (%).
Fig 1.
C-reactive protein (CRP) (Mean ±SEM) levels in patients with Staphylococcus aureus bacteremia (SAB) within 30 days of the positive blood culture.
(A) All 430 SAB patients. (B) SAB patients with a fatal outcome within 30 days (n = 53) and survivors (n = 377). (C) Mean CRP levels stratified according to the presence (n = 351) or absence (n = 79) of deep infection focus. Stars indicate p-values of the Student’s T-test. * p<0.05, ** p<0.01 and *** p<0.001.
Fig 2.
Receiver-operating characteristic (ROC) curve analyses of C-reactive protein (CRP) concentrations and white blood cell counts (WBC) with respect to 30-day mortality in Staphylococcus aureus bacteremia (n = 430).
The area under the curve (AUC) for CRP on the day 4 was 0.65 (95% CI, 0.55–0.76; p = 0.016) with a cut-off value of 104 mg/L with sensitivity of 77% and specificity of 55%. For CRP on the day 7 the AUC was 0.68 (95% CI, 0.58–0.79; p = 0.004) with a cut-off value of 66 mg/L with sensitivity of 73% and specificity of 55% and for CRP on day 14 the AUC was 0.86 (95% CI, 0.79–0.94; p<0.0001) with a cut-off value of 61mg/L with sensitivity of 82% and specificity of 80%. The corresponding AUC for WBC on the day 4 was 0.60 (95% CI, 0.49–0.71; p = 0.116) with a cut-off value of 8.0 x109/L with sensitivity of 86% and specificity of 41%. For WBC on the day 7 the AUC was 0.70 (95% CI, 0.62–0.78; p = 0.002) with a cut-off value of 9.8 x109/L with sensitivity of 77% and specificity of 62%. For WBC on the day 14 the AUC was 0.80 (95% CI, 0.70–0.92; p<0.0001) with a cut-off value of 8.6 x109/L with sensitivity of 77% and specificity of 78%.
Table 2.
Cut-off values for C-reactive protein (CRP) levels (mg/L) and white blood cell counts (WBC) in finding patients with fatal outcome among 430 patients with Staphylococcus aureus bacteremia.
OR = odds ratio for fatal outcome. HR = hazard ratio for fatal outcome, 95% CI = 95% confidence interval. All values are given as number of patients (%).
Fig 3.
Receiver-operating characteristic (ROC) curve analyses of C-reactive protein (CRP) concentrations and white blood cell counts (WBC) with respect to presence of any deep infection focus recorded during 30-days.
The area under the curve (AUC) for the day of the positive blood culture, CRP was 0.074 (95% CI, 0.67–0.81; p<0.0001) with a cut-off value of 108 mg/L with sensitivity of 77% and specificity of 60%. For CRP on day 7, the AUC was 0.75 (95% CI, 0.68–0.81; p<0.0001) with a cut-off value of 44 mg/L with sensitivity of 68% and specificity of 67% and for CRP on day 14 the AUC was 0.70 (95% CI, 0.64–0.77; p<0.0001) with a cut-off value of 22 mg/L with sensitivity of 59% and specificity of 68%. The corresponding AUC for WBC on the day 1 was 0.55 (95% CI, 0.46–0.63; p = 0.236) and a cut-off value was not determined. For WBC on day 7 the AUC was 0.65 (95% CI, 0.58–0.72; p<0.0001) with a cut-off value of 8.5 x109/L with sensitivity of 59% and specificity of 62%. For WBC on 14 days, the AUC was 0.56 (95% CI, 0.49–0.63; p = 0.153) with a cut-off value of 7.25 x109/L with sensitivity of 44% and specificity of 75%.
Table 3.
Factors associated with a deep infection focus in 430 patients with Staphylococcus aureus bacteremia.
OR = odds ratio for presence of deep infection, 95% CI = 95% confidence interval. All values are given as number of patients (%).