Comparison of risk factors for candidemia versus bacteremia in hospitalized patients

BACKGROUND

Classic risk factors for candidemia include use of total parenteral nutrition (TPN), hospital location, use of central venous catheter, and others. Unfortunately, most of these variables are now also risk factors for antibiotic-resistant bacteria. Thus, use of these risk factors to identify patients at high risk for candidemia is difficult. The purpose of this study was to compare these classic risk factors for candidemia in patients with bloodstream infections to determine the relative strength of these predictors in differentiating patients with candidemia and bacteremia.

METHODS

Clinical data were collected from the medical charts of patients who had been hospitalized between 2002 and 2004. Patients with their first episode of candidemia or bacteremia during their hospital stays were included. Risk factors were assessed using a multivariate logistic regression model and internally validated using a bootstrap analysis. A p-value < 0.05 was considered significant.

RESULTS

A total of 164 patients (82 with candidemia) were evaluated. According to the logistic analysis, patients who had stayed in the intensive care unit (ICU) (OR = 6.24; 95% CI: 2.58-15.09) or had been using TPN (OR = 4.69; 95% CI: 1.76-12.48) were more likely to have candidemia than bacteremia. While patients with pulmonary (OR = 0.15; 95% CI: 0.055-0.39) or cardiac disease (OR = 0.21; 95% CI: 0.086-0.51) had a greater chance to have bacteremia than candidemia (p < 0.01 for all variables). These results were further validated using bootstrap analysis.

CONCLUSION

Among classic risk factors for candidemia, the ICU location at the time of culture and TPN use were most predictive of candidemia while certain medical disorders predicted patients at the highest risk for bacteremia. These results can be used to help identify patients most likely to benefit from empiric antifungal therapy.

Inadequacy of fluconazole dosing in patients with candidemia based on Infectious Diseases Society of America (IDSA) guidelines

INTRODUCTION

Based on Infectious Diseases Society of America (IDSA) guidelines, inappropriate fluconazole therapy in patients with candidemia is defined as an empiric dose <6 mg/kg/d, <12 mg/kg/d after Candida glabrata identification, or continued fluconazole use after identification of Candida krusei. However, the extent to which inappropriate antifungal therapy is due to improper dosing or drug selection has not been well investigated. The objectives of this study were to assess the incidence of inappropriate fluconazole therapy in patients with candidemia and to identify variables associated with inappropriate therapy.

METHODS

Retrospective cohort study from four medical centers of hospitalized patients with candidemia prescribed fluconazole. Appropriateness of fluconazole dosages (adjusted for renal dysfunction) was assessed at the time of symptom onset and after Candida identification.

RESULTS

Patients (206) were identified. Sixty-one of 112 (55%) patients who were given empiric therapy received an initial dose of fluconazole <6 mg/kg. After identification of the Candida species, 97 of 206 (47%) patients received inadequate fluconazole therapy based on IDSA guideline recommendations due to a fluconazole dose <12 mg/kg after isolation of C. glabrata (12%), continued use of fluconazole after isolation of C. krusei (3%), or a dose <6 mg/kg for all other Candida species (32%). Using multivariate logistic regression, increased weight in 1-kg increments (OR: 1.02; p = 0.0142) and a creatinine clearance (CRCL) >50 ml/minute (OR: 3.17; p = 0.0003) were associated with increased risk of inadequate fluconazole therapy.

CONCLUSION

A high prevalence of suboptimal dosing of fluconazole given empirically or after Candida species identification was documented. Increased weight and CRCL were significant predictors of inadequate fluconazole doses.