Molecular Characterization and Antifungal Susceptibility of Clinical Fusarium Species From Brazil

Fusarium is widely distributed in the environment and is involved with plant and animal diseases. In humans, several species and species complexes (SC) are related to fusariosis, i.e., F. solani SC, F. oxysporum SC, F. fujikuroi SC, F. dimerum, F. chlamydosporum, F. incarnatum-equiseti, and F. sporotrichoides. We aimed to investigate the susceptibility of Fusarium clinical isolates to antifungals and azole fungicides and identify the species. Forty-three clinical Fusarium isolates were identified by sequencing translation elongation factor 1-alpha (TEF1α) gene. Antifungal susceptibility testing was performed to the antifungals amphotericin B, itraconazole, voriconazole, posaconazole, and isavuconazole, and the azole fungicides difenoconazole, tebuconazole, and propiconazole. The isolates were recovered from patients with median age of 36 years (range 2–78 years) of which 21 were female. Disseminated fusariosis was the most frequent clinical form (n = 16, 37.2%) and acute lymphoblastic leukemia (n = 7; 16.3%) was the most commonly underlying condition. A few species described in Fusarium solani SC have recently been renamed in the genus Neocosmospora, but consistent naming is yet not possible. Fusarium keratoplasticum FSSC 2 (n = 12) was the prevalent species, followed by F. petroliphilum FSSC 1 (n = 10), N. gamsii FSSC 7 (n = 5), N. suttoniana FSSC 20 (n = 3), F. solani sensu stricto FSSC 5 (n = 2), Fusarium sp. FSSC 25 (n = 2), Fusarium sp. FSSC 35 (n = 1), Fusarium sp. FSSC18 (n = 1), F. falciforme FSSC 3+4 (n = 1), F. pseudensiforme (n = 1), and F. solani f. xanthoxyli (n = 1). Amphotericin B had activity against most isolates although MICs ranged from 0.5 to 32 μg mL-1. Fusarium keratoplasticum showed high MIC values (8–>32 μg mL-1) for itraconazole, voriconazole, posaconazole, and isavuconazole. Among agricultural fungicides, difenoconazole had the lowest activity against FSSC with MICs of >32 μg mL-1 for all isolates

Initial Results of the International Efforts in Screening New Agents against Candida auris

This article belongs to the Special Issue Biology, Immunology, Epidemiology, and Therapy of Fungal Infections: A Themed Issue Dedicated to Professor David A. Stevens.Background: Candida auris is an emergent fungal pathogen and a global concern, mostly due to its resistance to many currently available antifungal drugs. Objective: Thus, in response to this challenge, we evaluated the in vitro activity of potential new drugs, diphenyl diselenide (PhSe)2 and nikkomycin Z (nikZ), alone and in association with currently available antifungals (azoles, echinocandins, and polyenes) against Candida auris. Methods: Clinical isolates of C. auris were tested in vitro. (PhSe)2 and nikZ activities were tested alone and in combination with amphotericin B, fluconazole, or the echinocandins, micafungin and caspofungin. Results: (PhSe)2 alone was unable to inhibit C. auris, and antagonism or indifferent effects were observed in the combination of this compound with the antifungals tested. NikZ appeared not active alone either, but frequently acted cooperatively with conventional antifungals. Conclusion: Our data show that (PhSe)2 appears to not have a good potential to be a candidate in the development of new drugs to treat C. auris, but that nikZ is worthy of further study.his work was accomplished with support from the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Brazil, within the scope of the Capes-PrInt Program—Financing Code 001info:eu-repo/semantics/publishedVersio

Emergence of fusarioses in a university hospital in Turkey during a 20-year period

Fusarium species have started appearing increasingly as the main cause of infections, particularly in immunocompromised patients. In this study, we aimed to present the first epidemiological data from Turkey, analyze fusariosis cases that have been monitored in a university hospital during the past 20 years, identify the responsible Fusarium species, and determine antifungal susceptibilities. A total of 47 cases of fusariosis was included in the study. Fusarium isolates were identified by multilocus sequence typing (MLST). Antifungal susceptibility was tested by the broth microdilution method according to the Clinical and Laboratory Standards Institute (CLSI) methodology. Of the Fusarium infections, 23.4 % were superficial, 44.7 % were locally invasive, and 31.9 % were disseminated. A significant increase was observed over the years. The Fusarium fujikuroi species complex (FFSC) proved to be the most frequent agent group (17 cases; 51.5 %), followed by the Fusarium solani species complex (FSSC) (14 cases; 42.4 %), the Fusarium dimerum species complex (FDSC), and the Fusarium oxysporum species complexes (FOSC) (one case each). Amphotericin B had the highest in vitro activity against all species. Voriconazole and posaconazole showed interspecies variability across and within Fusarium species complexes. In conclusion, our data support the fact that regional differences exist in the distribution of the Fusarium species and that species-specific differences are observed in antifungal susceptibility patterns. The monitoring of local epidemiological data by determining fungal identity and susceptibility are of importance in guiding the clinical follow-up of patients.Türk Mikrobiyoloji DerneğiMinistry of Health, Muscat, Oma

A comparison of isolation methods for black fungi degrading aromatic toxins

The prevalence of black fungi in the order Chaetothyriales has often been underestimated due to the difficulty of their isolation. In this study, three methods which are often used to isolate black fungi are compared. Enrichment on aromatic hydrocarbon appears effective in inhibiting growth of cosmopolitan microbial species and allows appearance of black fungi. We miniaturized the method for high-throughput purposes. The new procedure saves time, consumes less space and can process multiple samples simultaneously.info:eu-repo/semantics/publishedVersio

Evaluation of Candida colonization index, molecular identification, and antifungal susceptibility pattern of Candida species isolated from critically ill pediatric patients: A singlecenter study in Iran

Background and Purpose: Given the high mortality rate of invasive candidiasis inhospitalized pediatric patients, it is crucial to establish a predictive system to achieveearly diagnosis and treatment of patients who are likely to benefit from early antifungal treatment. This study aimed to assess the Candida colonization index, species distribution, and antifungal susceptibility pattern of Candida strains isolated frompediatric patients with high Candida colonization index (CI)Materials and Methods: This study was carried out at the Children’s Medical Center inTehran-Iran. In total, 661 samples were collected from 83 patients. The Candida CI wascalculated according to the descriptions of previous studies. The isolates were identified using polymerase chain reaction-based techniques. The Clinical and Laboratory Standard Institute protocol M60 was used to conduct the antifungal susceptibility test.Results: A colonization index greater than 0.5 was confirmed in 29 cases (58% ofpositive samples) with two children developing candidemia. Candida albicans (n=53,49.5%) was the most common Candida species in patients with CI > 0.5. Except foracute lymphoblastic leukemia, no risk factors were linked to a high index in colonizedchildren (P > 0.05). Twelve isolates (7.01%) were multi-azole resistant with high MICsagainst both isavuconazole and ravuconazole and seven strains (4.09%) wereechinocandins resistant.Conclusion: In pediatric intensive care units, patients are at risk of fungal infection,particularly candidemia. In this study, more than half of the children with positive yeastcultures had CI > 0.5, and 6.8% developed candidemia

In Vitro Activity of Chlorhexidine Compared with Seven Antifungal Agents against 98 Fusarium Isolates Recovered from Fungal Keratitis Patients.

Fungal keratitis is a common but severe eye infection in tropical and subtropical areas of the world. In regions with a temperate climate, the frequency of infection is rising in patients with contact lenses and following trauma. Early and adequate therapy is important to prevent disease progression and loss of vision. The management of Fusarium keratitis is complex, and the optimal treatment is not well defined. We investigated the in vitro activity of chlorhexidine and seven antifungal agents against a well-characterized collection of Fusarium isolates recovered from patients with Fusarium keratitis. The fungus culture collection of the Center of Expertise in Mycology Radboudumc/CWZ was searched for Fusarium isolates that were cultured from cornea scrapings, ocular biopsy specimens, eye swabs, and contact lens fluid containers from patients with suspected keratitis. The Fusarium isolates that were cultured from patients with confirmed keratitis were all identified using conventional and molecular techniques. Antifungal susceptibility testing was performed according to the EUCAST broth microdilution reference method. The antifungal agents tested included amphotericin B, voriconazole, posaconazole, miconazole, natamycin, 5-fluorocytosine, and caspofungin. In addition, the activity of chlorhexidine was determined. The fungal culture collection contained 98 Fusarium isolates of confirmed fungal keratitis cases from 83 Dutch patients and 15 Tanzanian patients. The isolates were collected between 2007 and 2017. Fusarium oxysporum (n = 24, 24.5%) was the most frequently isolated species followed by Fusarium solani sensu stricto (n = 18, 18.4%) and Fusarium petroliphilum (n = 11, 11.2%). Amphotericin B showed the most favorable in vitro inhibition of Fusarium species followed by natamycin, voriconazole, and chlorhexidine, while 5-fluorocytosine, posaconazole, miconazole, and caspofungin showed no relevant inhibiting effect. However, chlorhexidine showed fungicidal activity against 90% of F. oxysporum strains and 100% of the F. solani strains. Our study supports the clinical efficacy of chlorhexidine and therefore warrants its further clinical evaluation for primary therapy of fungal keratitis, particularly in low and middle income countries where fungal keratitis is much more frequent and, currently, antifungal eye drops are often unavailable

Basidiobolus omanensis sp. nov. Causing Angioinvasive Abdominal Basidiobolomycosis

Human infectious fungal diseases are increasing, despite improved hygienic conditions. We present a case of gastrointestinal basidiobolomycosis (GIB) in a 20-year-old male with a history of progressively worsening abdominal pain. The causative agent was identified as a novel Basidiobolus species. Validation of its novelty was established by analysis of the partial ribosomal operon of two isolates from different organs. Phylogeny of ITS and LSU rRNA showed that these isolates belonged to the genus Basidiobolus, positioned closely to B. heterosporus and B. minor. Morphological and physiological data supported the identity of the species, which was named Basidiobolus omanensis, with CBS 146281 as the holotype. The strains showed high minimum inhibitory concentrations (MICs) to fluconazole (>64 µg/mL), itraconazole and voriconazole (>16 µg/mL), anidulafungin and micafungin (>16 µg/mL), but had a low MIC to amphotericin B (1 µg/mL). The pathogenic role of B. omanensis in gastrointestinal disease is discussed. We highlight the crucial role of molecular identification of these rarely encountered opportunistic fungi

Estimated Burden of Fungal Infections in Oman

For many years, fungi have emerged as significant and frequent opportunistic pathogens and nosocomial infections in many different populations at risk. Fungal infections include disease that varies from superficial to disseminated infections which are often fatal. No fungal disease is reportable in Oman. Many cases are admitted with underlying pathology, and fungal infection is often not documented. The burden of fungal infections in Oman is still unknown. Using disease frequencies from heterogeneous and robust data sources, we provide an estimation of the incidence and prevalence of Oman’s fungal diseases. An estimated 79,520 people in Oman are affected by a serious fungal infection each year, 1.7% of the population, not including fungal skin infections, chronic fungal rhinosinusitis or otitis externa. These figures are dominated by vaginal candidiasis, followed by allergic respiratory disease (fungal asthma). An estimated 244 patients develop invasive aspergillosis and at least 230 candidemia annually (5.4 and 5.0 per 100,000). Only culture and microscopy are currently available for diagnosis, so case detection is suboptimal. Uncertainty surrounds these figures that trigger the need for urgent local epidemiological studies with more sensitive diagnostics