Trends in the Prevalence of Amphotericin B-Resistance (AmBR) among Clinical Isolates of Aspergillus Species.

The challenges of the invasive infections caused by the resistant Aspergillus species include the limited access to antifungals for treatment and high mortality. This study aimed to provide a global perspective of the prevalence of amphotericin B resistance (AmBR), geographic distribution, and the trend of AmBR from 2010 to 2020. To analyze the prevalence of in vitro AmBR in clinical Aspergillus species, we reviewed the literature and identified a total of 72 articles. AmBR was observed in 1128 out of 3061 Aspergillus terreus (36.8%), 538 out of 3663 Aspergillus flavus (14.9%), 141 out of 2691 Aspergillus niger (5.2%), and 353 out of 17,494 Aspergillus fumigatus isolates (2.01%). An increasing trend in AmB-resistant isolates of A. fumigatus and a decreasing trend in AmB-resistant A. terreus and A. flavus isolates were observed between 2016 and 2020. AmB-resistant A. terreus and A. niger isolates, accounting for 40.4% and 20.9%, respectively, were the common AmB-resistant Aspergillus species in Asian studies. However, common AmB-resistant Aspergillus species reported by European and American studies were A. terreus and A. flavus isolates, accounting for 40.1% and 14.3% in 31 studies from Europe and 25.1% and 11.7% in 14 studies from America, respectively. The prevalence of AmB-resistant A. niger in Asian isolates was higher than in American and European. We found a low prevalence of A. terreus in American isolates (25.1%) compared to Asian (40.4%) and European (40.1%). Future studies should focus on analyzing the trend of AmBR on a regional basis and using the same methodologies.

Global prevalence and subgroup analyses of coronavirus disease (COVID-19) associated Candida auris infections (CACa): A systematic review and meta-analysis.

BACKGROUND: Increased hospitalisation rates in the Coronavirus disease 19 (COVID-19) era lead to a new wave of hospital-acquired infections such as emerging multidrug-resistant Candida auris. We aimed to evaluate and estimate the global prevalence of coronavirus-associated C. auris infection (CACa). METHODS: We searched related databases between December 2019 and April 2022 for studies that reported data about CACa. Meta-analysis was performed using MedCalc software version 20.104 according to the DerSimonian and Laird method applying the random-effects model. We evaluated heterogeneity using the χ2 -based Q statistic (significant for p-value < .1) and the I2 statistic (>75% indicative of 'notable' heterogeneity). Moreover, if possible, an odds ratio (OR) analysis was performed for eligible data. RESULTS: Our meta-analysis includes ten eligible studies, including 1942 patients hospitalised with COVID-19; 129 were C. auris cases. The overall pooled prevalence of CACa was estimated at 5.7%. The mortality rate of CACa was estimated at 67.849%. Hypertension was the most prevalent comorbidity (59.374%), followed by diabetes mellitus (52.898%) and cardiovascular diseases (31.392%). Men with a prevalence rate of 80.012% were 3.27 (OR) times more prone to getting infected by C. auris. CONCLUSION: We concluded that the prevalence of C. auris infections decreased during the COVID-19 pandemic and the prevalence gradient changed from Asia to America. Unfortunately, there are many descriptive studies with duplicate content in the field of epidemiology of C. auris infections which are increasing every day. We suggest further non-descriptive studies to accurately establish the cause-and-effect relationships between C. auris and COVID-19 infections.

Post-antifungal effect of the combination of anidulafungin with amphotericin B and fluconazole against fluconazole-susceptible and -resistant Candida albicans.

Background and Purpose: Invasive candidiasis is a life-threatening condition that kills a large number of immunocompromised patients each year worldwide. We used post-antifungal effect studies to analyze the activities of anidulafungin (AFG), as a clinically crucial antifungal drug, amphotericin B (AMB), and fluconazole (alone and in combinations) against FLC-susceptible and -resistant Candida albicans (C. albicans) isolates obtained from the cancer patients. Materials and Methods: We tested the phenomenon of post antifungal effects of FLC, AMB, AFG, and combinations of FLC+AFG, AFG+AMB, and FLC+AMB against 17 C. albicans isolates obtained from the oral cavity of cancer patients. Isolates that had not been exposed to antifungals, served as a control group. Colony counts were performed at 0, 2, 4, 6, and 24 h after a brief (1 h) exposure to antifungal. Results: The FLC had no detectable post-antifungal effect independent of antifungal concentration and resembled drug-free FLC (control). Significant variations in the post-antifungal effect were observed when all AMB and AFG were compared to FLC. The combination of AFG and AMB with FLC resulted in effective activity compared to FLC alone. Combination regimens were rated as indifferent in general. Interestingly, low dosages of the AFG displayed increasing fungistatic action as it approached a fungistatic endpoint against C. albicans isolates (n=17). Conclusion: Our findings suggested that brief exposure to AFG, in combination with FLC and AMB, at low concentrations of the medicines utilized, could be effective in the evaluation and optimization of new dosage regimens to manage candidiasis. However, future studies will determine the clinical utility of our findings.

MALDI-TOF MS characterisation, genetic diversity and antifungal susceptibility of Trichosporon species from Iranian clinical samples.

BACKGROUND: Trichosporonosis is an emerging fungal infection caused by Trichosporon species, a genus of yeast-like fungi, which are frequently encountered in human infections ranging from mild cutaneous lesions to fungemia in immunocompromised patients. The incidence of trichosporonosis has increased in recent years, owing to higher numbers of individuals at risk for this infection. Although amphotericin B, posaconazole and isavuconazole are generally effective against Trichosporon species, some isolates may have variable susceptibility to these antifungals. OBJECTIVES: Herein, we evaluated the species distribution, genetic diversity and antifungal susceptibility profiles of Trichosporon isolates in Iran. METHODS: The yeasts were identified by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). Phylogenetic analysis was performed based on amplified fragment length polymorphism (AFLP). The in vitro susceptibilities of eight antifungal agents were analysed using the Clinical and Laboratory Standards Institute broth microdilution methods. RESULTS: The isolates belonged to the species T asahii (n = 20), T japonicum (n = 4) and T faecale (n = 3). A dendrogram of the AFLP analysis demonstrated that T asahii and non-asahii Trichosporon strains (T japonicum and T faecale) are phylogenetically distinct. While voriconazole was the most active agent (GM MIC = 0.075 µg/ml), high fluconazole MICs (8 µg/ml) were observed for a quarter of Trichosporon isolates. The GM MIC value of amphotericin B for T asahii and non-asahii Trichosporon species was 0.9 µg/ml. CONCLUSIONS: The distribution and antifungal susceptibility patterns of the identified Trichosporon species could inform therapeutic choices for treating these emerging life-threatening fungi.

Lack of association between vitamin D insufficiency and clinical outcomes of patients with COVID-19 infection.

BACKGROUND: A protective effect of vitamin D against COVID-19 infection is under investigation. We aimed to analyze the effect of vitamin D sufficiency on the clinical outcomes of patients infected with COVID-19. METHODS: In this cross-sectional study we analyzed the vitamin D levels of COVID-19 patients who were admitted to Razi Hospital (an infectious disease referral center in Mazandaran province in northern Iran) from February to March 2020. Overall, a cutoff point of 30 ng/mL was used for the definition of vitamin D sufficiency. RESULTS: One hundred fifty-three patients were analyzed in this study who had laboratory documentation of a 25(OH) D level at the time of hospitalization. The vitamin D levels of the patients were 27.19 ± 20.17 ng/mL. In total, 62.7% (n = 96) of the patients had a 25(OH) D level of less than 30 ng/mL and 37.25% (n = 57) had a 25(OH) D level of more than 30 ng/mL. In total, 49% (n = 75) of the patients suffered from at least one underlying disease. The univariate and multivariable regression showed that vitamin D sufficiency was not associated with a statistically significant lower risk of adverse clinical outcomes of COVID-19 such as duration of hospitalization and severity of infection (P > 0.05). CONCLUSIONS: Sufficient vitamin D levels were not found to be protective against adverse clinical outcomes in patients infected with COVID-19. Chronic disorders in COVID-19 patients were found to have greater relevance than vitamin D levels in determining the adverse outcomes of the infection. Further studies are needed to determine the role of vitamin D level in predicting the outcomes of COVID-19 infection.

Characterization of Candida species isolated from vulvovaginal candidiasis by MALDI-TOF with in vitro antifungal susceptibility profiles.

Background and Purpose: Vulvovaginal candidiasis (VVC) is an opportunistic infection due to Candida species, one of the most common genital tract diseases among reproductive-age women. The present study aimed to investigate the prevalence of VVC among non-pregnant women and identify the epidemiology of the involved Candida species with the evaluation of antifungal susceptibilities. Materials and Methods: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was performed to identify Candida species isolated from the genital tract of 350 non-pregnant women. Moreover, antifungal susceptibility testing was performed according to the Clinical and Laboratory Standards Institute broth microdilution method guidelines (M27-A3 and M27-S4). Results: Vaginal swab cultures of 119 (34%) women yielded Candida species. Candida albicans was the most frequently isolated species (68%), followed by Candida glabrata (19.2%). Voriconazole was the most active drug against all tested isolates showing an MIC50/MIC90 corresponding to 0.016/0.25 µg/mL, followed by posaconazole (0.031/1 µg/mL). Overall, resistance rates to fluconazole, itraconazole, and voriconazole were 2.4%, 4.8% and, 0.8% respectively. However, posaconazole showed potent in vitro activity against all tested isolates. Conclusion: Results of the current study showed that for the effectual therapeutic outcome of candidiasis, accurate identification of species, appropriate source control, suitable antifungal regimens, and improved antifungal stewardship are highly recommended for the management and treatment of infection with Candida, like VVC.