E. Forsblom

Telephone Consultation Cannot Replace Bedside Infectious Disease Consultation in the Management of Staphylococcus aureus Bacteremia

BACKGROUND Infectious disease specialist (IDS) consultation improves the outcome of Staphylococcus aureus bacteremia (SAB). Although telephone consultations constitute a substantial part of IDS consultations, their impact on treatment outcome lacks evaluation. METHODS We retrospectively followed 342 SAB episodes with 90-day follow-up, excluding 5 methicillin-resistant S. aureus SAB cases. Patients were grouped according to bedside, telephone, or no IDS consultation within the first week. Patients with fatal outcome within 3 days after onset of SAB were excluded to allow for the possibility of death occurring before IDS consultation. RESULTS Seventy-two percent of patients received bedside, 18% telephone, and 10% no IDS consultation. Patients with bedside consultation were less often treated in an intensive care unit during the first 3 days compared to those with telephone consultation (odds ratio [OR], 0.53; 95% confidence interval [CI], .29-.97; P = .037; 21% vs 34%), with no other initial differences between these groups. Patients with bedside consultation more often had deep infection foci localized as compared to patients with telephone consultation (OR, 3.11; 95% CI, 1.74-5.57; P < .0001; 78% vs 53%). Patients with bedside consultation had lower mortality than patients with telephone consultation at 7 days (OR, 0.09; 95% CI, .02-.49; P = .001; 1% vs 8%), at 28 days (OR, 0.27; 95% CI, .11-.65; P = .002; 5% vs 16%) and at 90 days (OR, 0.25; 95% CI, .13-.51; P < .0001; 9% vs 29%). Considering all prognostic markers, 90-day mortality for telephone-consultation patients was higher (OR, 2.31; CI, 95% 1.22-4.38; P = .01) as compared to bedside consultation. CONCLUSIONS Telephone IDS consultation is inferior to bedside IDS consultation.

High Cell-Free DNA Predicts Fatal Outcome among Staphylococcus aureus Bacteraemia Patients with Intensive Care Unit Treatment

Introduction Among patients with bacteraemia or sepsis the plasma cell-free DNA (cf-DNA) biomarker has prognostic value and Pitt bacteraemia scores predict outcome. We evaluated the prognostic value of plasma cf-DNA in patients with Staphylococcus aureus bacteraemia (SAB) treated in the ICU or in the general ward. Methods 418 adult patients with positive blood culture for S. aureus were prospectively followed for 90 days. SAB patients were grouped according to ICU treatment: 99 patients were treated in ICU within 7 days of documented SAB whereas 319 patients were managed outside ICU. Pitt bacteraemia scores were assessed at hospital arrival and cf-DNA was measured at days 3 and 5 from positive blood culture. Results SAB patients with high Pitt bacteraemia scores and ICU treatment presented higher cf-DNA values as compared to SAB patients with low Pitt bacteraemia scores and non-ICU treatment at both days 3 and 5. Among ICU patients cf-DNA >1.99 µg/ml at day 3 predicted death with a sensitivity of 67% and a specificity of 77% and had an AUC in receiver operating characteristic analysis of 0.71 (p<0.01). The cut-off cf-DNA >1.99 µg/ml value demonstrated a strong association to high Pitt bacteraemia scores (≥4 points) (p<0.000). After controlling for all prognostic markers, Pitt bacteraemia scores ≥4 points at hospital admission (OR 4.47, p<0.000) and day 3 cf-DNA (OR 3.56, p<0.001) were the strongest factors significantly predicting outcome in ICU patients. cf-DNA at day 5 did not predict fatal outcome. Conclusion High cf-DNA concentrations were observed among patients with high Pitt bacteraemia scores and ICU treatment. Pitt bacteraemia scores (≥4 points) and cf-DNA at day 3 from positive blood culture predicted death among SAB patients in ICU and were found to be independent prognostic markers. cf-DNA had no prognostic value among non-ICU patients.

Improved Outcome with Early Rifampicin Combination Treatment in Methicillin-Sensitive Staphylococcus aureus Bacteraemia with a Deep Infection Focus – A Retrospective Cohort Study

Introduction Rifampicin has been used as adjunctive therapy in Staphylococcus aureus bacteraemia (SAB) with a deep infection focus. However, data for prognostic impact of rifampicin therapy is unestablished including the optimal initiation time point. We studied the impact of rifampicin therapy and the optimal initiation time for rifampicin treatment on prognosis in methicillin-sensitive S. aureus bacteraemia with a deep infection. Methods Retrospective, multicentre study in Finland including 357 SAB patients with a deep infection focus. Patients with alcoholism, liver disease or patients who died within 3 days were excluded. Patients were categorised according to duration of rifampicin therapy and according to whether rifampicin was initiated early (within 7 days) or late (7 days after) after the positive blood cultures. Primary end point was 90 days mortality. Results Twenty-seven percent of patients received no rifampicin therapy, 14% received rifampicin for 1-13 days whereas 59% received rifampicin ≥14 days. The 90 day mortality was; 26% for patients treated without rifampicin, 16% for rifampicin therapy of any length and 10% for early onset rifampicin therapy ≥14 days. Lack of rifampicin therapy increased (OR 1.89, p=0.026), rifampicin of any duration decreased (OR 0.53, p=0.026) and rifampicin therapy ≥14 days with early onset lowered the risk for a fatal outcome (OR 0.33, p<0.01) during 90 days follow-up. Conclusion Rifampicin adjunctive therapy for at least 14 days and initiated within 7 days of positive blood culture associated with improved outcome among SAB patients with a deep infection.

Comparable Effectiveness of First Week Treatment with Anti-Staphylococcal Penicillin versus Cephalosporin in Methicillin-Sensitive Staphylococcus aureus Bacteremia: A Propensity-Score Adjusted Retrospective Study

The objective was to compare the prognostic impact of first week treatment with anti-staphylococcal penicillin (ASP) versus cephalosporin in methicillin-sensitive Staphylococcus aureus bacteremia (MS-SAB). Altogether 580 patients were retrospectively followed and categorized according to first week treatment; 84% (488) received ASP (cloxacillin) and 16% (92) cephalosporin (cefuroxime or ceftriaxone). SAB management was optimized with formal bedside infectious disease specialist consultation in 88%, deep infection foci diagnosed in 77% and adjunctive rifampicin therapy given to 61% of patients. The total case fatality in 580 patients was 12% at 28 days and 18% at 90 days. When comparing effectiveness of first week ASP versus cephalosporin treatment there were no significant differences in 28-days (11% vs. 12%, OR; 1.05, 95% CI, 0.53–2.09) or 90-days (17% vs. 21% OR; 1.25, 95% CI, 0.72–2.19) outcome. In univariate analysis no prognostic impact of either first week ASP or cephalosporin treatment was observed for 28-days (OR; 0.96, 95% CI, 0.48–1.90 and OR; 1.05, 95% CI, 0.53–2.09) or 90-days (OR; 0.80, 95% CI, 0.46–1.39 and OR; 1.25, 95% CI, 0.72–2.19) outcome. Propensity-score adjusted Cox proportional regression analysis for first week treatment with cephalosporin demonstrated no significant prognostic impact at 28-days (HR 1.54, 95% CI 0.72–3.23) or 90-days (HR 1.56, 95% CI 0.88–2.86). In conclusion: There is a comparable effectiveness with respect to 28- and 90-days outcome for first week treatment with ASP versus cephalosporin in MS-SAB. The results indicate that the difference in prognostic impact between first week ASP and cephalosporin may be non-significant in patient cohorts with SAB management optimized by infectious disease specialist consultation.

Microbiological Etiology and Treatment of Complicated Skin and Skin Structure Infections in Diabetic and Nondiabetic Patients in a Population-Based Study.

Abstract Background Diabetes is a major risk factor for skin and skin structure infection (SSSI), and the global burden of diabetics with SSSI is enormous. The more complex microbiology of diabetic foot infection (DFI) is well established, but it is not known whether microbiological etiology differs between diabetics and nondiabetics in other disease entities under the umbrella of complicated SSSI (cSSSI). Methods This retrospective, population-based study included patients with cSSSI, and it was conducted in 2 Nordic cities with a low prevalence of antimicrobial resistance. In analyses, patients (N = 460) were separated into 3 groups: diabetics (n = 119), nondiabetics (n = 271), and patients with DFI (n = 70). Results After exclusion of patients with DFI, there was no difference in the microbiological etiology or initial antimicrobial treatment of cSSSI between diabetics and nondiabetics. Gram-positive bacteria encountered 70% of isolations in diabetics and 69% in nondiabetics, and the empirical treatment covered initial pathogens in 81% and 86% of patients, respectively. However, diabetes was the only background characteristic in the propensity score-adjusted analysis associated with broad-spectrum antimicrobial use and longer antibiotic treatment duration. Patients with DFI had Gram-negative and polymicrobial infection more often than nondiabetics. Conclusions These observations suggest that diabetics without DFI are not different in the causative agents of cSSSI, although they are more exposed to antimicrobial therapy of inappropriate extended spectrum and long duration. Broad-spectrum coverage was clearly needed only in DFI. A clear opportunity for antimicrobial stewardship was detected in the rapidly growing population of diabetic patients with cSSSI.

Factors associated with time to clinical stability in complicated skin and skin structure infections

OBJECTIVES Factors associated with the time to clinical stability in patients with complicated skin and skin structure infection (cSSSI) were analysed in a retrospective population-based study. METHODS All hospitalized patients (n=402) with cSSSI in two Nordic cities during a 4-year period were included. Patient, disease, and treatment related factors were analysed in relation to early (0-3 days) or late (≥4 days) clinical stability. Clinical stability was assessed as improvement of infection related local and systemic signs. Furthermore, the effect of antimicrobial and other treatment on achievement of clinical stability was studied. RESULTS Clinical stability was reached within 0-3 days by 59% (239/402) of patients. In multivariable analysis later clinical stability was associated with admission to ICU (OR 10.1, 95% CI 4.01-25.3), posttraumatic wound infection (OR 3.17, 95% CI 1.31-7.69), bacteraemia (OR 3.09, 95% CI 1.36-7.02), surgical intervention after diagnosis (OR 2.64, 95% CI 1.36-5.11), diabetes (OR 2.33, 95% CI 1.28-4.25), and initial broad-spectrum antibiotic therapy (OR 3.03, 95% CI 1.43-6.40). Early stabilization within 3 days was associated with previous hospitalization (OR 0.47, 95% CI 0.22-0.99) and empirical antimicrobial therapy covering the initial pathogens (OR 0.38, 95% CI 0.18-0.80). Patients with clinical stability within 3 days were less likely to have treatment modifications and antimicrobial changes and had shorter hospital stay and antimicrobial treatment than those who stabilized later. CONCLUSIONS This study suggests that late treatment response depends on several baseline characteristics of patients and disease related factors other than treatment related factors.