Invasive Candidiasis.

Invasive candidiasis (IC) is the most frequent health care associated invasive fungal infection. It is also associated with high morbidity, mortality, and cost. The most frequent etiologic agent is Candida albicans, but non-albicans species are increasing and associated with reduced antifungal susceptibility and outbreaks. Candida auris is an emerging multidrug-resistant species recently described. IC presents as a spectrum of disease, going from fungemia to deep-seated candidiasis, and to septic shock with multiorgan failure. Diagnosis of IC is challenging. Several biomarkers and molecular methods are available for improving diagnosis. Early initial treatment with echinocandins is the treatment of choice. Step-down therapy when antifungal susceptibility is available is possible. Several new antifungal agents for the treatment of IC are in clinical development.

Clinical Outcomes in Patients With Gram-Negative Infections Treated With Optimized Dosing Cefepime Over Various Minimum Inhibitory Concentrations.

BACKGROUND: The Clinical and Laboratory Standards Institute (CLSI) revised cefepime interpretive criteria, introducing the susceptible dose-dependent category for Enterobacteriaceae with a minimum inhibitory concentration (MIC) of 4 to 8 µg/mL in 2014. Limited clinical data support these new categories. This study compares outcomes of patients treated with standard and high-dose cefepime across various MICs. METHODS: We retrospectively reviewed cases of pneumonia or bacteremia caused by gram-negative organisms treated with adequate doses of cefepime for ≥48 hours. Outcomes were compared for MICs of ≤2 (low), 4 (medium), and 8 µg/mL (high). The primary end point was clinical failure, the secondary end point was microbiological failure. RESULTS: Ninety cases met the inclusion criteria: 46, 25, and 19 patients with low, medium, or high MIC, respectively. Multivariate logistic regression revealed that the medium (odds ratio [OR]: 9.13, P < .01) and high (OR: 6.79, P = .01) MIC groups had increased clinical failure. CONCLUSION: Cefepime therapy, even at CLSI-recommended doses, had an increased risk of clinical failure for gram-negative pathogens with MICs of 4 or 8 µg/mL. This finding suggests that higher dosing regimens (2 g every 8 hours or 1 g every 6 hours) may be necessary to treat serious gram-negative infections with elevated MICs.

Impact of inappropriate antifungal therapy according to current susceptibility breakpoints on Candida bloodstream infection mortality, a retrospective analysis.

BACKGROUND: The mortality of Candida Bloodstream Infection (CBSI) remains high. Antifungal susceptibility breakpoints were recently updated for Candida species, the impact remains unknown. In this study we evaluated the impact of inappropriate antifungal treatment according to recent breakpoints on 30-day mortality of CBSI. METHODS: From June 2008 to July 2014, data on CBSI episodes from two tertiary-care centers, treated > 72 h were analyzed. Antifungal therapy and 30-day mortality were registered. Inappropriate antifungal treatment according to current Clinical & Laboratory Standards Institute (CLSI) breakpoints was adjusted with 30-day mortality-related co-variates. RESULTS: One hundred forty-nine episodes of CBSI were analyzed. The most frequent species were: C. albicans (40%), C. tropicalis (23%) and C. glabrata complex (20%). According to the 2012 CLSI, 10.7% received inappropriate treatment. The 30-day mortality was 38%; severe sepsis [Odds ratio (OR) 3.4; 95% CI 1.3-8.4], cirrhosis (OR 36; 95% CI 12.2-605), early central venous catheter removal (OR 0.23; 95% CI 0.08-0.66) and previous antifungal therapy (OR 0.15; 95%CI 0.03-0.62), were associated with 30-day mortality by multivariate analysis. Inappropriate antifungal treatment was not (OR 0.19; 95% CI 0.03-1.2). CONCLUSIONS: Appropriate antifungal therapy according to CLSI 2012 did not have an impact on mortality. Mortality of CBSI remains high due to disease severity and comorbidities; early antifungal therapy and catheter removal may reduce it.

Progressive Dispersion of Azole Resistance in Aspergillus fumigatus: Fatal Invasive Aspergillosis in a Patient with Acute Myeloid Leukemia Infected with an A. fumigatus Strain with a cyp51A TR46 Y121F M172I T289A Allele.

Patients with hematologic malignancies as well as allogeneic hematopoietic stem cell transplantation (HSCT) patients are at high risk for invasive aspergillosis. Here, we report a culture- and autopsy-proven fatal invasive aspergillosis in an allogeneic HSTC patient which he developed despite posaconazole prophylaxis. The agent was determined to be an azole-resistant Aspergillus fumigatus strain bearing the cyp51A mutation combination TR46 Y121F M172I T289A. At increasing frequency, the azole resistance of A. fumigatus is being reported globally, limiting treatment options and complicating regimens.

A Risk Score for Fluconazole Failure among Patients with Candidemia.

This study aimed to develop a prediction model to identify patients with candidemia who were at high risk of failing fluconazole treatment. Adult patients in the United States with candidemia who received fluconazole during hospitalization were selected from the Cerner Health Facts Hospital Database (04/2004 to 03/2013). Fluconazole failure was defined as switching/adding another antifungal, positive Candida culture ≥10 days after fluconazole initiation, or death during hospitalization. Patients were randomized into modeling and validation samples. Using the modeling sample, a regression analysis of least absolute shrinkage and selection operator was used to select risk predictors of fluconazole failure (demographics, Candida species, initiation of fluconazole before positive culture and after admission, and comorbidities, procedures, and treatments during the 6 months before admission and fluconazole initiation). The prediction model was evaluated using the validation sample. We found that of 987 identified patients (average age of 61 years, 51% male, 72% Caucasian), 49% failed and 51% did not fail fluconazole treatment. Of those who failed, 70% switched or added another antifungal, 21% had a second positive Candida test, and 42% died during hospitalization. Nine risk factors were included in the prediction model: days to start fluconazole after admission, Candida glabrata or Candida krusei infection, hematological malignancy, venous thromboembolism (VTE), enteral nutrition, use of nonoperative intubation/irrigation, and other antifungal use. All but VTE were associated with a higher risk of failure. The model's c-statistic was 0.65, with a Hosmer-Lemeshow test P value of 0.23. In summary, this prediction model identified patients with a high risk of fluconazole failure, illustrating the potential value and feasibility of personalizing candidemia treatment.

Comparative effectiveness of echinocandins versus fluconazole therapy for the treatment of adult candidaemia due to Candida parapsilosis: a retrospective observational cohort study of the Mycoses Study Group (MSG-12).

OBJECTIVES: A polymorphism in the gene encoding ß-1,3-glucan synthase, the target of the echinocandin class of antifungals, results in increased in vitro MICs of the echinocandins. This has resulted in controversy surrounding use of the echinocandins for treatment of Candida parapsilosis candidaemia. We aimed to compare 30 day mortality in adults with C. parapsilosis candidaemia treated with echinocandins versus fluconazole. METHODS: This is a retrospective observational cohort study. We used the Premier Perspective Database to identify adult patients with C. parapsilosis candidaemia treated with only fluconazole or only an echinocandin as definitive therapy. The primary outcome was 30 day mortality. Propensity scores were derived to estimate the probability the patient would have received either an echinocandin or fluconazole. Inverse probability of treatment weighting (IPTW) was used in a weighted logistic regression to calculate odds of 30 day mortality. RESULTS: There were 307 unique patients with C. parapsilosis candidaemia. One hundred and twenty-six (41%) received fluconazole and 181 (59%) received an echinocandin. Age, gender, race, year of admission, need for ICU resources in the week prior to candidaemia onset, and receipt of vasopressors on the day of candidaemia onset were included in the propensity score model used to calculate inverse probability of treatment weights. Weighted logistic regression demonstrated no difference in 30 day mortality between patients receiving an echinocandin as compared with fluconazole (OR 0.82, 95% CI 0.33-2.07). CONCLUSIONS: Our result supports the 2016 IDSA invasive candidiasis guidelines, which no longer clearly favour treatment with fluconazole over an echinocandin for C. parapsilosis candidaemia.

Cefepime free minimum concentration to minimum inhibitory concentration (fCmin/MIC) ratio predicts clinical failure in patients with Gram-negative bacterial pneumonia.

Cefepime is an antibiotic commonly used in nosocomial infections. The objective of this study was to elucidate the relationship between cefepime exposure and clinical outcome in patients with Gram-negative bacterial pneumonia. A previously published population pharmacokinetic model of cefepime was validated in 12 adult patients with normal renal function by measuring plasma concentrations at steady-state. Additionally, clinical outcomes for 33 patients with Gram-negative bacterial pneumonia who received cefepime monotherapy were determined. The free minimum concentration (fCmin) to MIC ratio for each patient was determined by conditioning the validated pharmacokinetic model using patient-specific creatinine clearance (CLCr), dosing regimen and cefepime MIC of the organism isolated, and was subsequently correlated with clinical failure. Classification and regression tree (CART) analysis was used to determine the most significant drug exposure breakpoint. Mean±S.D. CLCr and cefepime Cmin in the 12 patients were 87.5±21.2mL/min and 6.2±3.8mg/L, respectively. In comparison, the Cmin predicted by the pharmacokinetic model was 5.8mg/L using a CLCr of 90mL/min. MICs of organisms ranged from 0.5mg/L to 8mg/L. Percent time free drug above MIC of 100% was achieved in 32/33 patients, but 12 patients experienced clinical failure. CART analysis determined patients with an fCmin/MIC≥2.1 had a significantly lower risk of clinical failure (OR=0.11, 95% CI 0.02-0.67; P=0.017). The fCmin/MIC ratio is a useful predictor of clinical failure in Gram-negative bacterial pneumonia. The clinical utility of fCmin/MIC in therapeutic drug monitoring should be further explored.

Invasive candidiasis in the intensive care unit.

Invasive fungal disease by Candida spp. is on the rise in the modem era of prolonged patient survival by virtue of improved critical care measures, novel chemotherapy regimens, and increasing immunosuppression following organ transplants. Invasive candidiasis (IC) in the setting of an intensive care unit results in prolonged hospital stay and increased morbidity. Clinical suspicion plays a major role in the diagnosis of IC, as current laboratory methods are not very sensitive. Various serum markers and molecular techniques are under development to improve diagnostic strategies. Treatment options involve an expanding spectrum of antifungals. Knowledge of local epidemiology and the risk factors that predispose patients to this disease are essential for effective patient care in an intensive care setting.

Micafungin versus liposomal amphotericin B for candidaemia and invasive candidosis: a phase III randomised double-blind trial.

BACKGROUND: Invasive candidosis is increasingly prevalent in seriously ill patients. Our aim was to compare micafungin with liposomal amphotericin B for the treatment of adult patients with candidaemia or invasive candidosis. METHODS: We did a double-blind, randomised, multinational non-inferiority study to compare micafungin (100 mg/day) with liposomal amphotericin B (3 mg/kg per day) as first-line treatment of candidaemia and invasive candidosis. The primary endpoint was treatment success, defined as both a clinical and a mycological response at the end of treatment. Primary analyses were done on a per-protocol basis. This trial is registered with ClinicalTrials.gov, number NCT00106288. FINDINGS: 264 individuals were randomly assigned to treatment with micafungin; 267 were randomly assigned to receive liposomal amphotericin B. 202 individuals in the micafungin group and 190 in the liposomal amphotericin B group were included in the per-protocol analyses. Treatment success was observed for 181 (89.6%) patients treated with micafungin and 170 (89.5%) patients treated with liposomal amphotericin B. The difference in proportions, after stratification by neutropenic status at baseline, was 0.7% (95% CI -5.3 to 6.7). Efficacy was independent of the Candida spp and primary site of infection, as well as neutropenic status, APACHE II score, and whether a catheter was removed or replaced during the study. There were fewer treatment-related adverse events--including those that were serious or led to treatment discontinuation--with micafungin than there were with liposomal amphotericin B. INTERPRETATION: Micafungin was as effective as--and caused fewer adverse events than--liposomal amphotericin B as first-line treatment of candidaemia and invasive candidosis.

Associations between antibiotic use and changes in susceptibility patterns of Pseudomonas aeruginosa in a private, university-affiliated teaching hospital: an 8-year-experience: 1995-2002.

Increasing resistance in Pseudomonas aeruginosa to multiple antibiotics has been observed and is posing therapeutic dilemmas. Antibiotic utilization is one factor that has been associated with the emergence of antimicrobial resistance. We examined the overall and specific antimicrobial use in relation to changes in susceptibility patterns in P. aeruginosa. Regression analysis was performed to explore the relationships between annual antibiotic use and the incidence of resistant P. aeruginosa. There were statistically significant relationships between increasing anti-pseudomonal cephalosporin and levofloxacin use and the increasing incidence of ciprofloxacin resistant P. aeruginosa. However, there was not an association between other fluoroquinolone or overall fluoroquinolone use and this change. In addition, there was no association between increasing anti-pseudomonal cephalosporin use and cefepime resistant P. aeruginosa. No statistical relationship was seen with overall antibiotic use and the development of resistance in P. aeruginosa, suggesting that the development of resistance is associated with the use of individual agents, rather than overall antibiotic consumption.