The significance of persistent fever in the treatment of suspected bacterial infections among inpatients: a prospective cohort study

Fever Is Associated with Reduced, Hypothermia with Increased Mortality in Septic Patients: A Meta-Analysis of Clinical Trials

Background

Sepsis is usually accompanied by changes of body temperature (T_b), but whether fever and hypothermia predict mortality equally or differently is not fully clarified. We aimed to find an association between T_b and mortality in septic patients with meta-analysis of clinical trials.

Methods

We searched the PubMed, EMBASE, and Cochrane Controlled Trials Registry databases (from inception to February 2016). Human studies reporting T_b and mortality of patients with sepsis were included in the analyses. Average T_b with SEM and mortality rate of septic patient groups were extracted by two authors independently.

Results

Forty-two studies reported T_b and mortality ratios in septic patients (n = 10,834). Pearson correlation analysis revealed weak negative linear correlation (R² = 0.2794) between T_b and mortality. With forest plot analysis, we found a 22.2% (CI, 19.2–25.5) mortality rate in septic patients with fever (T_b > 38.0°C), which was higher, 31.2% (CI, 25.7–37.3), in normothermic patients, and it was the highest, 47.3% (CI, 38.9–55.7), in hypothermic patients (T_b < 36.0°C). Meta-regression analysis showed strong negative linear correlation between T_b and mortality rate (regression coefficient: -0.4318; P < 0.001). Mean T_b of the patients was higher in the lowest mortality quartile than in the highest: 38.1°C (CI, 37.9–38.4) vs 37.1°C (CI, 36.7–37.4).

Conclusions

Deep T_b shows negative correlation with the clinical outcome in sepsis. Fever predicts lower, while hypothermia higher mortality rates compared with normal T_b. Septic patients with the lowest (< 25%) chance of mortality have higher T_b than those with the highest chance (> 75%).

Sending repeat cultures: is there a role in the management of bacteremic episodes? (SCRIBE study)

Background

In the management of bacteremia, positive repeat blood cultures (persistent bacteremia) are associated with increased mortality. However, blood cultures are costly and it is likely unnecessary to repeat them for many patients. We assessed predictors of persistent bacteremia that should prompt repeat blood cultures.

Methods

We conducted a retrospective cohort study of bacteremias at an academic hospital from April 2010 to June 2014. We examined variables associated with patients undergoing repeat blood cultures, and with repeat cultures being positive. A nested case control analysis was performed on a subset of patients with repeat cultures.

Results

Among 1801 index bacteremias, repeat cultures were drawn for 701 patients (38.9 %), and 118 persistent bacteremias (6.6 %) were detected. Endovascular source (adjusted odds ratio [aOR], 7.66; 95 % confidence interval [CI], 2.30-25.48), epidural source (aOR, 26.99; 95 % CI, 1.91-391.08), and Staphylococcus aureus bacteremia (aOR, 4.49; 95 % CI, 1.88-10.73) were independently associated with persistent bacteremia. Escherichia coli (5.1 %, P = 0.006), viridans group (1.7 %, P = 0.035) and β-hemolytic streptococci (0 %, P = 0.028) were associated with a lower likelihood of persistent bacteremia. Patients with persistent bacteremia were less likely to have achieved source control within 48 h of the index event (29.7 % vs 52.5 %, P < .001), but after variable reduction, source control was not retained in the final multivariable model.

Conclusions

Patients with S. aureus bacteremia or endovascular infection are at risk of persistent bacteremia. Achieving source control within 48 h of the index bacteremia may help clear the infection. Repeat cultures after 48 h are low yield for most Gram-negative and streptococcal bacteremias.