Azole resistance in Aspergillus species in Southern Taiwan: An epidemiological surveillance study.

Poor clinical outcomes for invasive aspergillosis are associated with antifungal resistance. Performing antifungal susceptibility tests on clinically relevant Aspergillus isolates from patients and environmental regions with known azole resistance is recommended. The aim of the study was to assess the presence of azole resistance in clinical Aspergillus spp. isolates and those from hospital environments and farmlands within a 40 km radius of the hospital. Clinical Aspergillus spp. isolates were cultured, as well as environmental Aspergillus spp. isolates obtained from air samples. Samples were subcultured in azole-containing agar plates. Isolates with a positive screening test were subjected to YeastOne methods to determine their minimum inhibitory concentrations of antifungals. Resistance mechanisms were investigated in the azole-resistant Aspergillus spp. isolates. No azole-resistant clinical or environmental A flavus, A oryaze, A niger or A terreus isolates were found in the present study. All A fumigatus clinical isolates were azole-susceptible. Seven A fumigatus environmental isolates were associated with cyp51A mutations, including two that harboured TR34 /L98H mutations with S297T/F495I substitutions, two with TR34 /L98H mutations and three with TR46 /Y121F/T289A mutations. One of these isolates was collected from farmland, one was from A ward and five were from B ward. The proportion of azole-resistant A fumigatus was 10.2% (6/59) and 3.2% (1/31) in the hospital environments and the farmlands near the hospital, respectively. The results showed that azole-resistant A fumigatus existed within hospital environments. This emphasises the importance of periodic surveillance in hospital environments and monitoring for the emergence of azole-resistant A fumigatus clinical isolates.

The Impact of Biofilm Formation on the Persistence of Candidemia.

This study aimed to determine the predictors of persistent candidemia and examine the impact of biofilm formation by Candida isolates in adult patients with candidemia. Of the adult patients with candidemia in Kaohsiung Chang Gung Memorial Hospital between January 2007 and December 2012, 68 case patients with persistent candidemia (repeated candidemia after a 3-day systemic antifungal therapy) and 68 control patients with non-persistent candidemia (Candida clearance from the bloodstream after a 3-day systemic antifungal therapy) were included based on propensity score matching and matching for the Candida species isolated. Biofilm formation by the Candida species was assessed in vitro using standard biomass assays. Presence of central venous catheters (CVCs) at diagnosis (adjusted odd ratio [AOR], 3.77; 95% confidence interval [CI], 1.09-13.00, p = 0.04), infection with higher biofilm forming strains of Candida species (AOR, 8.03; 95% CI, 2.50-25.81; p < 0.01), and receipt of suboptimal fluconazole doses as initial therapy (AOR, 5.54; 95% CI, 1.53-20.10; p < 0.01) were independently associated with persistent candidemia. Biofilm formation by Candida albicans, C. tropicalis, and C. glabrata strains was significantly higher in the case patients than in the controls. There were no significant differences in the overall mortality and duration of hospitalization between the two groups. Our data suggest that, other than presence of retained CVCs and use of suboptimal doses of fluconazole, biofilm formation was highly associated with development of persistent candidemia.

Antifungal therapy did not improve outcomes including 30-day all-cause mortality in patients suffering community-acquired perforated peptic ulcer-associated peritonitis with Candida species isolated from their peritoneal fluid.

BACKGROUND/PURPOSE: Although patients suffering community-acquired perforated peptic ulcer (PPU)-associated peritonitis with Candida species isolated from their peritoneal fluid have higher chances of mortality and experiencing a complicated postoperative clinical course, universal antifungal therapy for these patients remains controversial. METHODS: This is a retrospective analysis of the impacts of antifungal therapy on outcomes of patients suffering community-acquired PPU-associated peritonitis with Candida species isolated from their ascites at a medical center in Taiwan. All included patients received source control and antibiotic treatment, with or without additional postoperative antifungal therapy with fluconazole or an echinocandin for at least 3 days. RESULTS: Among the 133 included patients, 76 did not receive (Group 1) and 57 did receive (Group 2) antifungal therapy. Sixteen (12%) of the overall included patients died within 30 days. Shock [odds ratio (OR), 5.6; 95% confidence interval (CI), 1.9-16.5; p = 0.002] and higher Acute Physiology and Chronic Health Evaluation II score (>20; OR, 9.5; 95% CI, 1.1-80.7; p = 0.04) were independently associated with 30-day mortality. Among the 80 matched patients from Groups 1 and 2 (1:1 matched) with the closest propensity score, no significant difference was found in 30-day all-cause mortality, time to mortality, the need for reoperation/abscess formation/anastomotic leakage, prolonged intensive care unit stay, and prolonged mechanical ventilator dependence between patients with and without antifungal therapy. CONCLUSION: Our study provides solid evidence supporting the notions that antifungal therapies do not benefit patients suffering PPU peritonitis with Candida species isolated from their ascites in general, and antifungal therapy could be reserved for patients who are critically ill and/or severely immunocompromised.