Genetic Diversity and In Vitro Antifungal Susceptibility of 200 Clinical and Environmental Aspergillus flavus Isolates

Loop-mediated Isothermal Amplification Test for Rapid Identification of Clinical Nocardia Isolates

Background: Nocardia is a Gram-positive and partially acid-fast bacterium. The species are widely distributed in the environment and cause severe human infections. Nocardiosis is not easily identifiable due to the lack of pathognomonic clinical signs. Objectives: The present study was designed to develop and evaluate a simple and quick method based on a loop-mediated isothermal amplification (LAMP) assay for detecting Nocardia spp isolated from bronchoalveolar lavage (BAL) samples. Methods: In this cross-sectional study, 357 BAL samples were collected from two teaching hospitals. The polymerase chain reaction (PCR) was performed using a set of species-specific primers for the 16S rRNA gene. Kinyoun acid-fast staining and culture were done on the Sabouraud dextrose plate. The optimal LAMP reaction condition was set at 65°C for 45 min, with the recognition limit as 1 pg DNA/tube and 100 CFU/reaction. In addition to calcein and manganous ions, agarose gel electrophoresis was used to visualize the amplified LAMP products. Results: Out of 357 BAL samples, 0 (0.0%), 4 (1.1%), 9 (2.5%), and 10 (2.8%) Nocardia strains were identified by direct staining of partial acid-fast, streak culture plate, PCR, and LAMP methods, respectively. Conclusions: We developed a new LAMP technique for the recognition of Nocardia, which is fast, very precise, simple, and low-cost. According to our knowledge, this is the first report of the LAMP method to detect Nocardia in clinical samples.

Refractory invasive pulmonary aspergillosis due to Aspergillus flavus detected with the combination of two in-house Aspergillus qPCR

We present a case of probable invasive pulmonary aspergillosis due to Aspergillus flavus, in a female patient treated for an acute myeloid leukemia. Two weeks after an allogenic stem cell transplantation a probable invasive pulmonary aspergillosis was diagnosed based on thoracic imaging combined with positive galactomannan antigen and positive in-house mitochondrial Aspergillus qPCR in serum. Although an antifungal treatment was initiated, Aspergillus qPCR and galactomannan antigen remained positive in serum and worsening of the thoracic lesions was observed. The discordance between the negativity of the in-house ribosomal Aspergillus qPCR (specific to A. fumigatus) and the positivity of the in-house mitochondrial Aspergillus qPCR (targeting A. fumigatus and some other Aspergillus) allowed the suspicion of a thermophilic Aspergillus species that was not A. fumigatus. No strain was obtained in culture but the involvement of A. flavus was confirmed using a specific A. flavus qPCR. This case illustrated the usefulness of our original strategy combining two different in-house Aspergillus qPCRs, in addition to galactomannan assay, to diagnose invasive aspergillosis in hematology patients.

Flucytosine and its clinical usage

Flucytosine is an antifungal agent first licensed in the 1970's. However, its clinical value has long been overlooked and its availability across the globe is limited. This review highlights the important clinical and pharmacological aspects of flucytosine. This a narrative review of the clinical and in vitro susceptibility literature, with a focus on clinical uses for flucytosine. Detailed literature review including early literature related to primary and acquired resistance to flucytosine. Flucytosine has good antifungal activity against Cryptococcus species, Candida species, and dematiaceous fungi. Its water solubility enables good penetration into the eye, urinary tract, central nervous system (CNS), cardiac vegetations and fungal biofilms. In combination with amphotericin B, it shows early fungicidal activity against Cryptococcus species, and this translates to ~20% improved survival in cryptococcal meningitis. Combination therapy also reduces the mortality of Candida meningitis, and should be used in neonatal candidiasis because of the high frequency of CNS infection. Monotherapy for urinary candidiasis is under-studied, but is usually effective. It is probably valuable in the treatment of Candida endocarditis and endophthalmitis: there are few data. It is not effective for aspergillosis or mucormycosis. Flucytosine monotherapy of urinary candidiasis resulted in 22% developing resistance on therapy and failing therapy, and in 29% of 21 patients with cryptococcosis. Certain regions of the world still do not have access to flucytosine compromising the management of certain severe fungal infections. Flucytosine has an important role in combination therapy for yeast and dematiaceous infections and probably as monotherapy for urinary candidiasis, with a modest risk of resistance emergence. Facilitating access to flucytosine in those regions (especially low-income countries) might alleviate the mortality of invasive fungal diseases.

Characterization of 260 Isolates of Aspergillus Section Flavi Obtained from Sesame Seeds in Punjab, Pakistan

Sesame Sesamum indicum L. is a major oil-based seed crop that has been widely cultivated and consumed in Pakistan. Unfortunately, sesame is highly prone to Aspergillus fungal growth in the field, and under inappropriate storage conditions can become contaminated with aflatoxins, the most potent carcinogen found in nature. Here, we have isolated a high number of Aspergillus isolates from sesame seeds in fresh and stored conditions obtained from rainfed and irrigated zones of Punjab, Pakistan, and characterized them for aflatoxigenic potentials. Using morphological identification techniques, 260 isolates were grouped as potential Aspergillus section Flavi, with 126 and 134 originating from the rainfed and irrigated zones, respectively. Out of 260 in total, 188 isolates were confirmed to produce aflatoxins. There were no significant differences in potential aflatoxigenic isolates with respect to the rainfed and irrigated zones. However, the number of potential aflatoxigenic isolates was significantly higher (p < 0.05) in stored samples than that of those from fresh sesame seeds in the rainfed and irrigated zone. Whole genome sequencing and comparative analyses of 12 select isolates have revealed that one of the A. flavus isolates, which produced very low aflatoxins (AFP10), has an elevated missense variant rate, numerous high impact mutations, and a 600 base pair deletion in the norB gene. In summary, our study provides insights into aflatoxigenic potential and the associated genetic diversity of indigenous Aspergillus section Flavi isolates and potential management strategies for reducing aflatoxin contamination levels in a major crop consumed in Punjab, Pakistan.

The Effect of Ocimum basilicum L. and Its Main Ingredients on Respiratory Disorders: An Experimental, Preclinical, and Clinical Review

Ocimum basilicum L. (O. basilicum) and its constituents show anti-inflammatory, immunomodulatory, and antioxidant effects. The plant has been mainly utilized in traditional medicine for the treatment of respiratory disorders. In the present article, effects of O. basilicum and its main constituents on respiratory disorders, assessed by experimental and clinical studies, were reviewed. Relevant studies were searched in PubMed, Science Direct, Medline, and Embase databases using relevant keywords including “Ocimum basilicum,” “basilicums,” “linalool,” “respiratory disease,” “asthma,” “obstructive pulmonary disease,” “bronchodilatory,” “bronchitis,” “lung cancer,” and “pulmonary fibrosis,” and other related keywords.The reviewed articles showed both relieving and preventing effects of the plant and its ingredients on obstructive pulmonary diseases such as chronic obstructive pulmonary disease (COPD), asthma, and other respiratory disorders such as bronchitis, aspergillosis tuberculosis, and lung cancer. The results of the reviewed articles suggest the therapeutic potential of O. basilicum and its constituent, linalool, on respiratory disorders.

COVID-19 Associated Pulmonary Aspergillosis: Diagnostic Performance, Fungal Epidemiology and Antifungal Susceptibility

Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) raises concerns as to whether it contributes to an increased mortality. The incidence of CAPA varies widely within hospitals and countries, partly because of difficulties in obtaining a reliable diagnosis. We implemented a routine screening of respiratory specimens in COVID-19 ICU patients for Aspergillus species using culture and galactomannan (GM) detection from serum and/or bronchoalveolar lavages (BAL). Out of 329 ICU patients treated during March 2020 and April 2021, 23 (7%) suffered from CAPA, 13 of probable, and 10 of possible. In the majority of cases, culture, microscopy, and GM testing were in accordance with CAPA definition. However, we saw that the current definitions underscore to pay attention for fungal microscopy and GM detection in BALs, categorizing definitive CAPA diagnosis based on culture positive samples only. The spectrum of Aspergillus species involved Aspergillus fumigatus, followed by Aspergillus flavus, Aspergillus niger, and Aspergillus nidulans. We noticed changes in fungal epidemiology, but antifungal resistance was not an issue in our cohort. The study highlights that the diagnosis and incidence of CAPA is influenced by the application of laboratory-based diagnostic tests. Culture positivity as a single microbiological marker for probable definitions may overestimate CAPA cases and thus may trigger unnecessary antifungal treatment.

Mycetoma due to Aspergillus flavus in a diabetic patient: Case report and literature review

Diabetes mellitus patients are prone to cutaneous and subcutaneous fungal infections due to pathogenic fungi, including dermatophytes, Mucorales, Candida, Aspergillus, and Fusarium species. Here, we report a case of A. flavus mycetoma confirmed by isolation and molecular identification. The case was a 38-year-old male farmer with a seven-year history of type 2 diabetes mellitus, living in Khuzestan, southwest of Iran. The patient presented with a right foot swelling associated with a nodule and multiple discharging sinuses following trauma sustained on the foot while working barefoot on the rice farm, a year ago. The nodule appeared at the site of the trauma two months after the injury. The initial diagnosis was based on direct microscopic examination of lesions scraping using 20% potassium hydroxide and radiology. Molecular analysis confirmed the isolates to be A. flavus. In vitro susceptibility of the isolate to voriconazole, posaconazole, caspofungin, itraconazole, and amphotericin B was determined. Treatment with voriconazole (200 mg twice daily) stopped the purulent discharge, reduced the swelling, and improved the clinical condition within two months. The study emphasizes the importance of wearing footwear to prevent skin trauma as the main risk factor of patient involvement.

Triazole susceptibility of Aspergillus species: environmental survey in Lagos, Nigeria and review of the rest of Africa

Background:

Triazole resistance is an emerging problem in the management of human aspergillosis globally and can arise in Aspergillus species which have been exposed to azole fungicides in the environment. We surveyed local government and council development areas in Lagos, Nigeria, to determine the distribution of Aspergillus species in the environment and their susceptibility to locally available triazole antifungal agents. We also reviewed the literature on the subject from the rest of Africa.

Methods:

A total of 168 soil samples from six locations in Lagos, Nigeria were processed and cultured on Saboraud dextrose agar impregnated with chloramphenicol to isolate Aspergillus species. Isolates were tested for susceptibility to itraconazole and voriconazole by microbroth dilution according to the European Committee on Antimicrobial Susceptibility Testing reference method. Relevant databases were searched to identify published work pertaining to triazole susceptibility of Aspergillus species in Africa.

Results:

A total of 117 Aspergillus species were isolated. Aspergillus niger was the most frequently isolated species (42.7%). Other species isolated were Aspergillus flavus, 37 (31.6%), Aspergillus terreus, 20 (17.1%), Aspergillus fumigatus, 5 (4.3%) and Aspergillus nidulans, 5 (4.3%). All isolates were susceptible to itraconazole and voriconazole. The literature review showed documented evidence of triazole-resistant Aspergillus species from East and West Africa.

Conclusions:

We found no triazole resistance in environmental isolates of Aspergillus in Lagos, Nigeria. Nevertheless, regular surveillance in clinical and environmental isolates is necessary in the light of findings from other African studies.

Emergence of Triazole Resistance in Aspergillus spp. in Latin America

Purpose of Review

Azole resistance in Aspergillus spp. is becoming a public health problem worldwide. However, data about this subject is lacking in Latin American countries. This review focuses in the epidemiology and molecular mechanisms of azole resistance in Aspergillus spp. emphasizing in Latin America. Data on Aspergillus fumigatus stands out because it is the most prevalent Aspergillus spp. pathogen.

Recent Findings

Azole resistance in Aspergillus spp. emergence was linked with intensive use of these antifungals both in the clinical setting and in the environment (as pesticides). Reports on azole-resistant A. fumigatus strains are being constantly published in different countries. Molecular mechanisms of resistance mainly involve substitution in the azole target (CYP51A) and/or overexpression of this gene. However, several other non-CYP51A-related mechanisms were described. Moreover, intrinsically resistant cryptic Aspergillus species are starting to be reported as human pathogens.

Summary

After a comprehensive literature review, it is clear that azole resistance in Aspergillus spp. is emerging in Latin America and perhaps it is underestimated. All the main molecular mechanisms of azole resistance were described in patients and/or environmental samples. Moreover, one of the molecular mechanisms was described only in South America. Cryptic intrinsic azole-resistant species are also described.

Case Report: Infective Endocarditis Caused by Aspergillus flavus in a Hemodialysis Patient

Fungal endocarditis (FE) is a rare but fatal disease. The incidence of infective endocarditis (IE) in hemodialysis patients with catheters is thought to be obviously higher than that in the general population. We reported a case of IE caused by Aspergillus flavus (A. flavus) in a 36-year-old woman on hemodialysis. Because the blood cultures were persistently negative, so we used mNGS (Metagenomic next generation sequencing) for early clinical diagnosis. After treatment with voriconazole, the patient's condition improved rapidly. She continued oral voriconazole treatment 1 year after discharge and is in good condition. The diagnosis and treatment strategies of FE in hemodialysis patients were discussed.

Identification and in vitro antifungal susceptibility of causative agents of onychomycosis due to Aspergillus species in Mashhad, Iran

Aspergillus species are emerging causative agents of non-dermatophyte mold onychomycosis. In this study, 48 Aspergillus isolates were obtained from patients with onychomycosis in Mashhad, Iran, during 2015–2018. The aim is to identify the Aspergillus isolates to the species level by using partial calmodulin and beta-tubulin gene sequencing and MALDI-TOF MS, and to evaluate their in vitro susceptibility to ten antifungal drugs: terbinafine, itraconazole, voriconazole, posaconazole, ravuconazole, isavuconazole, caspofungin, micafungin, anidulafungin and amphotericin B according to CLSI M38-A3. Our results indicate that A.flavus (n = 38, 79%) is the most common Aspergillus species causing onychomycosis in Mashhad, Iran. Other detected species were A. terreus (n = 3), A. tubingensis (n = 2), A. niger (n = 1), A. welwitschiae (n = 1), A. minisclerotigenes (n = 1), A. citrinoterreus (n = 1) and A. ochraceus (n = 1). Aspergillus flavus, A. terreus and A. niger isolates were correctly identified at the species level by MALDI-TOF MS, while all cryptic species were misidentified. In conclusion, A. flavus is the predominant Aspergillus species causing onychomycosis due to Aspergillus spp. in Mashhad, Iran. MALDI-TOF MS holds promise as a fast and accurate identification tool, particularly for common Aspergillus species. It is important that the current database of reference spectra, representing different Aspergillus species is expanded to increase the precision of the species-level identification. Terbinafine, posaconazole and echinocandins were in vitro most active against the studies Aspergillus isolates and terbinafine could be the first choice for treatment of onychomycosis due to Aspergillus.

Drug-Resistant Aspergillus flavus Is Highly Prevalent in the Environment of Vietnam: A New Challenge for the Management of Aspergillosis?

The burden of aspergillosis, especially Chronic Pulmonary Aspergillosis, is increasingly recognized, and the increasing presence of azole-resistant environmental Aspergillus fumigatus has been highlighted as a health risk. However, a sizable minority of aspergillosis is caused by Aspergillus flavus, which is assumed to be sensitive to azoles but is infrequently included in surveillance. We conducted environmental sampling at 150 locations in a rural province of southern Vietnam. A. flavus isolates were identified morphologically, their identity was confirmed by sequencing of the beta-tubulin gene, and then they were tested for susceptibility to azoles and amphotericin B according to EUCAST methodologies. We found that over 85% of A. flavus isolates were resistant to at least one azole, and half of them were resistant to itraconazole. This unexpectedly high prevalence of resistance demands further investigation to determine whether it is linked to agricultural azole use, as has been described for A. fumigatus. Clinical correlation is required, so that guidelines can be adjusted to take this information into account.

Fatal Prosthetic Valve Endocarditis Due to Aspergillus flavus in a Diabetic Patient

Aspergillus endocarditis (AE) accounts for a-quarter of all fungal endocarditis, mainly in immunocompromised hosts prior to heart-valve surgery with high mortality, even with treatment. Herein, we report a rare case of AE in a diabetic 60-year-old woman with a history of redo mitral valve prosthesis suspecious of acute endocarditis. She underwent second redo surgical mitral valve replacement in combination with mechanical aortic valve replacement. Blood cultures were negative. The explanted valve and vegetation were subjected to identification. Grown colonies were identified as Aspergillus flavus, based on conventional and molecular methods. Despite the administration of liposomal amphotericin B and improvement in her general condition shortly after initiation of therapy, the patient passed away. As AE is a late consequence of redo prosthetic valve replacement, extended follow-up, early diagnosis, repeating valve-replacement surgeries, and timely selective antifungal treatments are warranted.

The high efficacy of luliconazole against environmental and otomycosis Aspergillus flavus strains

BACKGROUND AND OBJECTIVES

Luliconazole is currently confirmed for the topical therapy of dermatophytosis. Moreover, it is found that luliconazole has in vitro activity against some molds and yeast species. The aim of the present study was to evaluate the efficacy of luliconazole in comparison to routine used antifungals on clinical and environmental isolates of Aspergillus flavus.

MATERIALS AND METHODS

Thirty eight isolates of A. flavus (18 environmental and 20 clinical isolates) were detected based on morphological and microscopic features and also PCR-sequencing of β-tubulin ribosomal DNA gene. All the isolates were tested against luliconazole, voriconazole, amphotericin B and caspofungin. Minimum inhibitory concentration (MIC), MIC₅₀, MIC₉₀ and MIC Geometric (GM) were calculated using CLSI M38-A2 protocol for both environmental and clinical isolates.

RESULTS

Luliconazole with extremely low MIC range, 0.00049-0.00781 μg/mL and MIC_GM 0.00288 μg/mL showed very strong activity against both clinical and environmental A. flavus isolates. Moreover, voriconazole inhibited 100% of isolates at defined epidemiological cutoff values (ECV ≤ 2 μg/ml). 50% and 27.8% of clinical and environmental isolates of A. flavus, were resistant to caspofungin, respectively. Whereas, all the isolates were found to be resistant to amphotericin B.

CONCLUSION

The analysis of our data clearly indicated that luliconazole (with MIC_GM 0.00244 μg/ml for clinical and 0.00336 μg/ml for environmental isolates) had the highest in vitro activity against A. flavus strains.

Microbiology of hospital wastewater

The study of hospital wastewater (HWW) microbiology is important to understand the pollution load, growth of particular pathogenic microbes, shift and drift in microbial community, development and spread of antibiotic resistance in microbes, and subsequent change in treatment efficiencies. This chapter investigates the potential microbes such as bacteria, viruses, fungi, and parasites present in HWW along with the diseases associated and methods of treatment used. Due to the indiscriminate release of antibiotics from hospitals, HWW serves as a hotspot for emergence of antibiotic-resistance genes (ARGs) and antibiotic-resistance bacteria. This chapter discusses the ARGs occurrence in HWW, their prevalence in the environment, the molecular tools used for identification, and different mechanisms of horizontal gene transfer. Thus better understanding of the microbiology of HWW could further help in development of advanced treatment technologies for effective removal of microbes and their bioproducts (toxins and infectious nucleic acid) from HWW and contaminated water.

Role of Clotrimazole in Prevention of Recurrent Otomycosis

Otomycosis is one of the relatively common diseases in the world which is caused by different fungi especially saprophytes. Concerning the relapse of this disease in a number of individuals, the present study was performed to evaluate the inhibitory effect of clotrimazole drop in the relapse of otomycosis. Clinical samples were taken by an ENT specialist from patients suspicious of having otomycosis. A part of these samples were stained, and others were cultured. The diagnosis of otomycosis was made on the basis of the recognizable and characteristic appearance of fungal hyphae or mycelium and fruiting bodies and/or conidiophores under microscopic examination. Patients with suspected otomycosis are not at risk of recurrence after treatment with clotrimazole drops. Out of the 161 individuals in whom definite diagnosis of otomycosis was made, the most affected individuals were, in the age range of 40–49 years, women, urban citizens, and housewives. Pruritus and diminished hearing were the main complaints of the patients. Aspergillus niger and A. flavus as well as Candida albicans were the main causes of the disease. The relapse of disease was observed in only five patients (3.1%), where A. niger was the main fungus. Most relapses were observed in women and in those with diminished hearing, manipulating the ears, ulcers in the canal, and tympanum. Our results suggested that usage of clotrimazole can be effective in reducing the relapse of otomycosis, and concerning the high cost of treating otomycosis while the low cost of using clotrimazole, usage of this drop is recommended to reduce the relapse of otomycosis.

Genetic diversity and antifungal susceptibility patterns of Aspergillus nidulans complex obtained from clinical and environmental sources

The molecular epidemiology and antifungal susceptibility of Aspergillus nidulans species complex has not been well studied. To evaluate the genetic diversity and antifungal susceptibility patterns of clinical and environmental isolates of A. nidulans complex. Sixty clinical and environmental isolates of Aspergillus section Nidulantes were collected from five countries (Iran, The Netherlands, Spain, Portugal and Greece). The species were molecularly identified by sequencing of β-tubulin gene. The genetic diversity of A nidulans complex isolates (n = 54) was determined with a microsatellite genotyping assay. Antifungal susceptibility profile was determined using EUCAST method. The isolates were classified as A nidulans (46.7%), A spinulosporus (26.6%), A quadrilineatus (10%), A pachycristatus (3.3%), A rugulosus (3.3%), A unguis (5%), A creber, (1.7%), A olivicola (1.7%) and A sydowii (1.7%). Thirty-four sequence types (STs) were identified among the 54 A nidulans complex isolates. A high level of genetic diversity was found among A nidulans sensu stricto strains but low diversity was found among A spinulosporus strains. Amphotericin B showed high MICs to all species. The most active azole was posaconazole (GM = 0.64 mg/L), while itraconazole showed the highest MICs among azoles (GM = 2.95 mg/L). A spinulosporus showed higher MICs than A nidulans sensu stricto for all antifungals except for micafungin and anidulafungin. Interspecies variations may result in differences in antifungal susceptibility patterns and challenge antifungal therapy in infections caused by A nidulans. Differences in the distribution of STs or persistence of multiple STs might be related to the sources of isolation and niche specialisation.

Discrimination of Aspergillus flavus from Aspergillus oryzae by matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) mass spectrometry

BACKGROUND

Aspergillus flavus is a major cause of severe non-invasive fungal infections in the Middle Eastern countries. However, it is difficult to distinguish A flavus from A oryzae.

OBJECTIVES

To assess the potential of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) in discriminating between A flavus and A oryzae and compare it with β-tubulin gene sequencing.

METHODS

We used the Bruker Daltonik MALDI-TOF MS system to analyse 200 clinical and environmental A flavus isolates and one A pseudonomius and one A alliaceus (Aspergillus section Flavi) isolate a priori identified as such by sequencing of the β-tubulin gene.

RESULTS

All 200 A flavus isolates were identified at the genus level and 176 (88%) at the species levels by MALDI-TOF MS based on the spectral log-scores (≥2.0 and 1.7-1.99, respectively); among them, only 18 (10.2%) were confirmed as A flavus, whereas 35 (19.9%) were identified as A oryzae and 123 (69.9%) as A flavus/A oryzae. Aspergillus pseudonomius and A alliaceus were misidentified as A flavus and A parasiticus with log-score values of 1.39 and 1.09, respectively.

CONCLUSIONS

The results indicate that the commercially available Bruker Daltonik MALDI-TOF MS score database cannot separate A flavus and A oryzae species. We also showed that establishment of an in-house library is a useful tool to discriminate closely related Aspergillus species, including A flavus and A oryzae.

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.

Detection of virulence factors and antifungal susceptibility of human and avian Aspergillusflavus isolates

Aspergillusflavus is the second leading cause of invasive and non-invasive aspergillosis. Secretion of hydrolytic enzymes is considered as a virulence factor in this species. Our work aimed to study in vitro production of some virulence factors, to evaluate the biofilm production against human and avian A. flavus isolates and to investigate the antifungal susceptibility agents. Hydrolytic enzymes, biofilm production and molecular typing were studied for 62 human and 36 avian A. flavus isolates by specific solid media and six microsatellite markers. The susceptibility to antifungal agents was evaluated for 37 human isolates. All human and avian A. flavus isolates showed positive activities of extracellular hydrolase: phospholipase, protease and hemolysin. A positive elastase activity was seen in 64.51% of human A. flavus isolates and 86.1% of avian A. flavus isolates. All A. flavus in these two populations formed biofilms. Statistical significant difference was observed for the mean phospholipase activities (P=0.025) and biofilm quantification (P=0.0001) between human and avian A. flavus isolates. The in vitro susceptibility results showed a resistance in 83.7%, 81.08% and 16.21% of A. flavus isolates respectively to amphotericin B, itraconazole and posaconazole. No association was noted between all virulence factors and the genotypes of human and avian isolates. Our study allowed us to show that human strains have a higher production of extracellular hydrolases and biofilm then avian strains. These virulence factors appear to act synergistically to contribute to the virulence of A. flavus strains. Moreover, significant correlation between virulence patterns and antifungal susceptibility profiles was observed.

Invasive Aspergillosis by Aspergillus flavus: Epidemiology, Diagnosis, Antifungal Resistance, and Management

Aspergillus flavus is the second most common etiological agent of invasive aspergillosis (IA) after A. fumigatus. However, most literature describes IA in relation to A. fumigatus or together with other Aspergillus species. Certain differences exist in IA caused by A. flavus and A. fumigatus and studies on A. flavus infections are increasing. Hence, we performed a comprehensive updated review on IA due to A. flavus. A. flavus is the cause of a broad spectrum of human diseases predominantly in Asia, the Middle East, and Africa possibly due to its ability to survive better in hot and arid climatic conditions compared to other Aspergillus spp. Worldwide, ~10% of cases of bronchopulmonary aspergillosis are caused by A. flavus. Outbreaks have usually been associated with construction activities as invasive pulmonary aspergillosis in immunocompromised patients and cutaneous, subcutaneous, and mucosal forms in immunocompetent individuals. Multilocus microsatellite typing is well standardized to differentiate A. flavus isolates into different clades. A. flavus is intrinsically resistant to polyenes. In contrast to A. fumigatus, triazole resistance infrequently occurs in A. flavus and is associated with mutations in the cyp51C gene. Overexpression of efflux pumps in non-wildtype strains lacking mutations in the cyp51 gene can also lead to high voriconazole minimum inhibitory concentrations. Voriconazole remains the drug of choice for treatment, and amphotericin B should be avoided. Primary therapy with echinocandins is not the first choice but the combination with voriconazole or as monotherapy may be used when the azoles and amphotericin B are contraindicated.

Study on the relationship between the concentration and type of fungal bio-aerosols at indoor and outdoor air in the Children's Medical Center, Tehran, Iran

Fungal bio-aerosols are of concern due to their adverse health effects, especially in indoor environments. The aim of this study was to evaluate the relationship between the concentration and type of fungal bio-aerosols in the indoor and outdoor of Children's Medical Center in Tehran, Iran. In the present descriptive-analytical study, the fungal bio-aerosols' concentrations in both indoor and outdoor of the hospital air were measured. The measurements were carried out by the Anderson method using a Quick Take 30 pump at 28.3 L min^-1 and 2.5 min sampling that was placed on a Sabouraud dextrose agar with chloramphenicol. The average concentrations of total fungal bio-aerosols in the hospital indoor and outdoor air were 40.48 and 119.6 CFU/m³, respectively. Onco-hematology and bone marrow transplantation wards were the most and least contaminated units, respectively (11.09 CFU/m³ vs 1.47 CFU/m³). The most common fungi isolated from the indoor environment were Penicillium spp. (45.86%) which was followed by Cladosporium spp. (31.92%), Aspergillus section Nigri (6.26%), sterilized mycelia (5.05%), and Aspergillus section Flavi (2.83%). Cladosporium spp. (61.10 CFU/m³) and Penicillium spp. (18.56 CFU/m³) had the highest mean concentrations in outdoor and indoor air, respectively. The indoor-to-outdoor ratio of fungal aerosols was < 1 at most sampling sites, indicating that the indoor fungal bio-aerosols may have originated from the outdoor environment.

In-vitro antifungal susceptibility testing of lanoconazole and luliconazole against Aspergillus flavus as an important agent of invasive aspergillosis

INTRODUCTION

The incidence of Aspergillus infections has recently increased remarkably in certain tropical and sub-tropical countries, with Aspergillus flavus being identified as the leading cause of infections after A. fumigatus. Lanoconazole (LAN) and luliconazole (LUL) are currently approved for topical treatment of cutaneous fungal infections. We aimed the in-vitro antifungal susceptibility testing of two imidazole, LAN and LUL against A. flavus.

METHODS

One hundred and eighty-seven clinical and environmental A. flavus were tested originating from different climate zones of Iran between 2008 and 2015. The identification of all isolates was confirmed by using PCR-sequencing of β-tubuline ribosomal DNA gene. In-vitro antifungal susceptibility test was performed using CLSI guidelines against LAN, LUL, itraconazole (ITC), voriconazole (VRC), posaconazole (POS), Isavuconazole (ISA), amphotericin B (AMB), 5-flucytosine (5FC), caspofungin (CAS) and anidulafungin (AFG). The minimum inhibitory concentration (MIC) and minimum effect concentration (MEC) values were evaluated according to CLSI M38-A2 guidelines.

RESULTS

The geometric mean MICs for tested antifungals, in increasing order, were: 0.009 μg/mL for LUL (ranging from 0.004 to 0.062), 0.02 μg/mL for LAN (ranging from 0.004 to 0.125), POS (0.10), ISA (0.16), ITC (0.24), VRC (0.27), AMB (1.8) and 5FC (63.06) μg/mL. The mean value of MECs for AFG and CAS were 0.06 and 0.07, respectively.

CONCLUSION

Overall, LUL and LAN showed the lowest MIC against all isolates of A. flavus. Further studies are required to evaluate the in-vivo efficacy of these agents, and the possibility of using these agents in systemic infections.

Effect of combination therapy with ceftizoxime and clotrimazole in the treatment of otomycosis

Background and Purpose:

There are controversial findings regarding the efficacy of antifungal drugs in the treatment of a ruptured eardrum following fungal infections. Regarding this, the aim of the present study was to evaluate the therapeutic effect of the co-administration of antifungal and antibacterial agents in the treatment of otomycosis with tympanic membrane perforation.

Materials and Methods:

This analytical, clinical trial was conducted on 87 patients with otomycosis showing no bacterial elements in the direct observation and culture. The study population was assigned into two groups of intervention (n=45) and control (n=42). The demographic and clinical data, as well as the data related to the direct observation and culture of the ear samples were recorded in a checklist. All statistical analysis was performed in SPSS (version 24).

Results:

The most prevalent symptoms in both groups were hearing loss and itching, and the most common finding was secretion. Aspergillus and Candida were the most frequent fungi isolated from the samples. After the implementation of combination therapy, the intervention group demonstrated a significant decrease in symptoms and signs, compared to the control group (P=0.005).

Conclusion:

The findings of the present study indicated that the use combination therapy with ceftizoxime powder and clotrimazole ointment was effective the in treatment of the patients with tympanic membrane rupture showing no bacterial effects in direct examination and culture.

In vitro antifungal susceptibility of clinical and environmental isolates of Aspergillus fumigatus and Aspergillus flavus in Brazil

The in vitro susceptibility of 105 clinical and environmental strains of Aspergillus fumigatus and Aspergillus flavus to antifungal drugs, such as amphotericin B, azoles, and echinocandins was evaluated by the broth microdilution method proposed by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Following the EUCAST-proposed breakpoints, 20% and 25% of the clinical and environmental isolates of A. fumigatus, respectively, were found to be resistant to itraconazole (Minimal Inhibitory Concentration, MIC > 2.0 mg/L). Voriconazole showed good activity against A. fumigatus and A. flavus strains, except for one clinical strain of A. fumigatus whose MIC was 4.0 mg/L. Posaconazole (≤0.25 mg/L) also showed appreciable activity against both species of Aspergillus, except for six A. fumigatus strains with relatively higher MICs (0.5 mg/L). The MICs for Amphotericin B ranged from 0.06 to 1.0 mg/L for A. fumigatus, but were much higher (0.5–8.0 mg/L) for A. flavus. Among the echinocandins, caspofungin showed a geometric mean of 0.078 and 0.113 against the clinical and environmental strains of A. flavus, respectively, but had elevated minimal effective concentrations (MECs) for seven of the A. fumigatus strains. Anidulafungin and micafungin exhibited considerable activity against both A. fumigatus and A. flavus isolates, except for one environmental isolate of A. fumigatus that showed an MEC of 1 mg/L to micafungin. Our study proposes that a detailed investigation of the antifungal susceptibility of the genus Aspergillus from different regions of Brazil is necessary for establishing a response profile against the different classes of antifungal agents used in the treatment of aspergillosis.