Management Of Aspergillosis Research Articles

P-2131. Identification of Non-fumigatus Aspergillus Species in Clinical Samples from Southern California

Abstract Background Aspergillus is the causative agent of aspergillosis, with presentations ranging from mild skin infections to disseminated disease affecting the central nervous system. Fungal culture from the infected site is the current recommendation to confirm presence of Aspergillus and to speciate based on morphology. A. fumigatus has historically been identified as the source of most serious infections, but there is emerging concern for invasive disease caused by non-fumigatus­ species, especially those that may carry intrinsic resistance to recommended antifungals. In this descriptive analysis, we reviewed trends in Aspergillus species cultured from a large clinical cohort.Figure 1.Percentage of Positive Aspergillus cultures by specimen origin type over time 2012-2023. Methods We identified all positive fungal cultures for at least one Aspergillus species across Kaiser Permanente Southern California hospitals and clinics from January 2012–June 2023. Episodes were defined as a combination of any Aspergillus culture results conducted within 30 days of the first positive Aspergillus culture. Only the first episode for each patient was included in analyses if multiple episodes were identified.Figure 2.Number of positive Aspergillus cultures by species identified and specimen type. Results 10,777 patients were identified at KPSC with at least one positive Aspergillus culture between 2012 and 2023. Isolates were most frequently identified from samples associated with the respiratory tract and bronchoalveolar lavage fluid. However, the proportion of cutaneous cultures has increased over time and was nearly equal to the number of positive respiratory cultures in 2023 (Figure 1). Aspergillus niger (n=3,772) was the most frequently cultured Aspergillus species overall, with 44.6% of isolates originating from skin, nail, and scalp samples (Figure 2). Aspergillus fumigatus was identified in 40.3% of respiratory sample cultures, followed by Aspergillus niger at 25.7%. Finally, non-fumigatus specimens exhibited seasonal trends in respiratory samples compared to A. fumigatus, peaking in early autumn each year (Figure 3).Figure 3.Number of positive Aspergillus cultures in respiratory samples by reported species by month. Conclusion Non-fumigatus species were identified more frequently than A. fumigatus in culture of respiratory and non-respiratory clinical samples. Novel observations of seasonal trends and increasing predominance of non-fumigatus species may indicate a shift in clinical expectations and treatment options during management of aspergillosis. Disclosures Emily Rayens, PhD, MPH, GSK: Grant/Research Support|Moderna: Grant/Research Support Sara Y. Tartof, PhD MPH, GSK: Grant/Research Support|Pfizer Inc: Grant/Research Support

The mitochondrial protein Bcs1A regulates antifungal drug tolerance by affecting efflux pump expression in the filamentous pathogenic fungus Aspergillus fumigatus.

Aspergillus fumigatus is the predominant pathogen responsible for aspergillosis infections, with emerging drug-resistant strains complicating treatment strategies. The role of mitochondrial functionality in fungal resistance to antifungal agents is well-documented yet not fully understood. In this study, the mitochondrial protein Bcs1A, a homolog of yeast Bcs1, was found to regulate colony growth, ion homeostasis, and the response to antifungal drugs in A. fumigatus. Microscopic observations revealed substantial colocalization of Bcs1A-GFP fusion protein fluorescence with mitochondria. Bcs1A deletion compromised colony growth and the utilization of non-fermentable carbon sources, alongside causing abnormal mitochondrial membrane potential and reduced reactive oxygen species production. These findings underscore Bcs1A's vital role in maintaining mitochondrial integrity. Phenotypic analysis and determinations of minimum inhibitory concentrations indicated that the Δbcs1A mutant was more resistant to various antifungal agents, such as azoles, terbinafine, and simvastatin, compared to wild-type strain. RNA sequencing and RT-qPCR analysis highlighted an upregulation of multiple efflux pumps in the Δbcs1A mutant. Furthermore, loss of the principal drug efflux pump, mdr1, decreased azole tolerance in the Δbcs1A mutant, suggesting that Bcs1A's modulated of azoles response via efflux pump expression. Collectively, these results establish Bcs1A as essential for growth and antifungal drug responsiveness in A. fumigatus mediated through mitochondrial regulation.IMPORTANCEDrug resistance presents a formidable obstacle in the clinical management of aspergillosis. Mitochondria are integral to various biochemical pathways, including those involved in fungi drug response, making mitochondrial proteins promising therapeutic targets for drug therapy. This study confirms that Bcs1A, a mitochondrial respiratory chain protein, is indispensable for mitochondrial functionality and multidrug tolerance in Aspergillus fumigatus. Mutation of Bcs1A not only leads to a series of drug efflux pumps upregulated but also shows that loss of the primary efflux pump, mdr1, partial reduction in drug tolerance in the Bcs1A mutant, highlighting that Bcs1A's significant influence on mitochondria-mediated drug resistance.

Successful management of Aspergillosis in post renal transplant patient: A case report

This case describes a 60-year-old man with a history of diabetes and hypertension who underwent a kidney transplant in September 2023. The patient presented with fever, cough for 5 days, empirical antibiotics were started but complaints were not resolved so fungal markers were sent, which showed elevated galactomannan levels, necessitating the initiation of voriconazole therapy. X Ray chest showed patch along with cavitatory lesion which was further confirmed by CT Scan Chest which confirmed a cavitatory lesion. This case report emphasizes the importance of considering fungal infection as a differential diagnosis in immunocompromised patients and achieving good results with appropriate treatment.

Aspergillosis: an Update on Clinical Spectrum, Diagnostic Schemes, and Management.

This review gives an overview of the diseases caused by Aspergillus, including a description of the species involved and the infected clinical systems. We provide insight into the various diagnostic methods available for diagnosing aspergillosis, particularly invasive aspergillosis (IA), including the role of radiology, bronchoscopy, culture, and non-culture-based microbiological methods. We also discuss the available diagnostic algorithms for the different disease conditions. This review also summarizes the main aspects of managing infections due to Aspergillus spp., such as antifungal resistance, choice of antifungals, therapeutic drug monitoring, and new antifungal alternatives. The risk factors for this infection continue to evolve with the development of many biological agents that target the immune system and the increase of viral illnesses such as coronavirus disease. Due to the limitations of present mycological test methods, establishing a fast diagnosis is frequently difficult, and reports of developing antifungal resistance further complicate the management of aspergillosis. Many commercial assays, like AsperGenius®, MycAssay Aspergillus®, and MycoGENIE®, have the advantage of better species-level identification and concomitant resistance-associated mutations. Fosmanogepix, ibrexafungerp, rezafungin, and olorofim are newer antifungal agents in the pipeline exhibiting remarkable activity against Aspergillus spp. The fungus Aspergillus is found ubiquitously around the world and can cause various infections, from harmless saprophytic colonization to severe IA. Understanding the diagnostic criteria to be used in different patient groups and the local epidemiological data and antifungal susceptibility profile is critical for optimal patient management.

Social Mycology: Using Social Media Networks in the Management of Aspergillosis and Other Mycoses.

Online social media networks are an integral part of modern life. Microblogging sites such as Twitter have hundreds of millions of active users globally and have been enthusiastically adopted by many in the medical profession. For advancing a relatively neglected field such as fungal infection, this can be especially advantageous. Education, research networking, case discussions and public and patient engagement can all be greatly enhanced through the use of social media networks. This review highlights the ways in which this can work successfully in the case of aspergillosis and fungal infection in general, as well as highlighting the dangers and pitfalls of social media medicine.

Epidemiology and antifungal susceptibilities of clinically isolated Aspergillus species in South China.

Aspergillosis is a rising concern worldwide; however, its prevalence is not well documented in China. This retrospective study determined Aspergillus's epidemiology and antifungal susceptibilities at Meizhou People's Hospital, South China. From 2017 to 2022, the demographic, clinical, and laboratory data about aspergillosis were collected from the hospital's records and analysed using descriptive statistics, chi-square test, and ANOVA. Of 474 aspergillosis cases, A. fumigatus (75.32%) was the most common, followed by A. niger (9.92%), A. flavus (8.86%), and A. terreus (5.91%). A 5.94-fold increase in aspergillosis occurred during the study duration, with the highest cases reported from the intensive care unit (52.74%) - chronic pulmonary aspergillosis (79.1%) and isolated from sputum (62.93%). Only 38 (8.02%) patients used immunosuppressant drugs, while gastroenteritis (5.7%), haematologic malignancy (4.22%), and cardiovascular disease (4.22%) were the most prevalent underlying illnesses. In A. fumigatus, the wild-type (WT) isolates against amphotericin B (99.1%) were higher than triazoles (97-98%), whereas, in non-fumigatus Aspergillus species, the triazole (95-100%) WT proportion was greater than amphotericin B (91-95%). Additionally, there were significantly fewer WT A. fumigatus isolates for itraconazole and posaconazole in outpatients than inpatients. These findings may aid in better understanding and management of aspergillosis in the region.

Innate and Adaptive Immune Responses Induced by Aspergillus fumigatus Conidia and Hyphae.

Previous research indicated that hyphae of Aspergillus fumigatus (A. fumigatus) rather than conidia could successfully build a pulmonary aspergillosis model in immunocompetent mice. In this study, we compared the immune responses induced by hyphae and conidia to explore the possible mechanism of this striking phenomenon. Herein, a novel method was designed and adopted to quantify hyphal fragments. Murine macrophages RAW264.7 and human peripheral blood mononuclear cells were stimulated by A. fumigatus hyphae and conidia in vitro, respectively, and then immunological reactions were measured. Male C57BL/6 mice were challenged with conidia and hyphae through intratracheal inoculation. Dynamic conditions of mice were recorded, and RNA-seq measured corresponding immune responses. The results of the study confirmed that hyphae could induce more intensive inflammation than conidia in vitro and in vivo. However, macrophages revealed a higher production of ROS and M1 polarisation in response to conidia stimuli. Additionally, conidia could promote Th1 cell differentiation, while hyphae could increase the CD4/CD8 ratio. RNA-seq validated the fact that those multiple immunologically relevant pathways were more strongly activated by hyphae than conidia, which also promoted Th2 cell differentiation and suppressed Th1 signalling. Both hyphae and conidia could activate Th17 signalling. In general, conidia and hyphae induced distinctly different host immune responses, and the immune responses induced by conidia played a better protective effect. Therefore, the unique function of hyphae in the spread and infection of Aspergillus should be emphasised, and more research is required to clarify the underlying mechanisms for better understanding and management of aspergillosis.

RAPID DEVELOPMENT AND PROGRESSION OF INVASIVE PULMONARY ASPERGILLOSIS

RAPID DEVELOPMENT AND PROGRESSION OF INVASIVE PULMONARY ASPERGILLOSIS

MANAGEMENT AND IDENTIFICATION OF RARE COINFECTIONS

MANAGEMENT AND IDENTIFICATION OF RARE COINFECTIONS

P026 Antifungal activity of a novel triazole and comparators against a large collection of identified Aspergillus isolates

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM Aspergillus species are capable of causing both invasive disease and chronic infections in immunocompromised patients or those with preexisting lung conditions. Management of superficial aspergillosis is a significant challenge owing to the frequent relapses and treatment failure, which may pose a potential risk, thereby gradually developing resistant species. So, necessitating the development of new antifungals with higher potency should be considered alternative strategies for efficient management of aspergillosis. We investigated the susceptibility patterns of Aspergillus isolates toward efinaconazole compared with various antifungal drugs. Antifungal susceptibility testing was performed according to the CLSI (M38) guidelines. Efinaconazole exhibited poor activity against azole-resistant A. fumigatus strains, A. niger sensu stricto, and A. tubingensis with GM MIC values of 3.62, 1.62, and 2 mg/l, respectively; however, surprisingly, it efficiently inhibited the growth of A. terreus sensu stricto, followed by wild-type A. fumigatus and A. flavus with GM MIC values of 0.29, 0.42, and 0.52 mg/l, respectively. Presumably, efinaconazole is inefficient in aspergillosis treatment due to the low susceptibility of A. niger sensu stricto, A. tubingensis, and azole-resistant A. fumigatus; however, it may be effective in treating superficial aspergillosis caused by susceptible A. fumigatus, A. terreus sensu stricto, and A. flavus. Differences in susceptibility patterns were observed between the generA. Awareness of the epidemiology of Aspergillus isolates and differences in antifungal susceptibility patterns around the globe may aid clinicians in choosing antifungal treatment regimens. However, studies are warranted to correlate these findings with clinical outcomes. Therefore, further studies are needed to determine how these findings may translate into in vivo efficacy.

An Unexpected Guest in a Patient With Ulcerative Colitis

Question: A 16-year-old girl with a 2-year history of ulcerative colitis was referred to our university hospital because of fever, vomiting, and epigastric pain for 10 days; bloody diarrhea during the last month; and a rapid involuntary weight loss (5 kg). Sixth months earlier, during remission with oral mesalamine (60 mg/kg), she suffered a mild-to-moderate ulcerative colitis flare-up requiring oral prednisolone (1 mg/kg for 2 weeks and then tapered). At admission, physical examination showed pallor, mild signs of dehydration, and diffuse abdominal pain without signs of peritoneal irritation. Written consent for publication was obtained from the patient and her parents. Laboratory investigations revealed anemia, mild eosinophilia, hypoalbuminemia, an increased erythrocyte sedimentation rate, and fecal calprotectin. Specific serologic tests and blood and stool cultures for bacteria and viruses were negative. Colonoscopy showed pancolitis with continuous diffuse granular and friable mucosa (Mayo Score of 2) and upper endoscopy showed antral gastritis and diffuse duodenitis with nonbleeding erosions. The patient was started on steroids (1 mg/kg) followed by the amelioration of diarrhea, but persistence of mild grade fever and vomiting. Histologic examination showed crypt distortions and abscesses associated with goblet cell depletion. An upper endoscopy showed a normal esophageal and gastric mucosa. Duodenal histology (periodic acid–Schiff staining method) is presented in Figure A. What is the diagnosis? See the Gastroenterology web site (www.gastrojournal.org) for more information on submitting your favorite image to Clinical Challenges and Images in GI. Aspergillus fumigatus was identified in duodenal biopsy specimens. Serum galactomannan antigen test (Bio-rad Platelia Aspergillus Ag kit) and specific IgM (DRG IgM ELISA) assays were positive (index 4.1 and 6.5 UI/mL, respectively); chest and brain computed tomography scans were normal.1Donnelly J.P. Chen S.C. Kauffman C.A. et al.Revision and update of the consensus definitions of invasive fungal disease from the European Organization for Research and Treatment of Cancer and the Mycoses Study Group Education and Research Consortium.Clin Infect Dis. 2020; 71: 1367-1376Crossref PubMed Scopus (898) Google Scholar Antifungal treatment with voriconazole (loading dose: 6 mg/kg/12 h on the first day, then 4 mg/kg/12 h) was started and steroids were tapered.2Patterson T.F. Thompson 3rd, G.R. Denning D.W. et al.Practice guidelines for the diagnosis and management of aspergillosis: 2016 update by the Infectious Diseases Society of America.Clin Infect Dis. 2016; 63: e1-e60Crossref PubMed Scopus (1405) Google Scholar A comprehensive immune assessment was performed after discontinuing steroid therapy. After 1 week of treatment, the clinical condition and inflammatory markers improved. Aspergillus fumigatus is a ubiquitous saprophytic fungus with low pathogenicity in healthy individuals, but may be the major cause of life-threatening infection in immunocompromised individuals. Enteric aspergillosis is an uncommon presentation of invasive aspergillosis, which can disseminate hematogenously to other organs. Clinical features of invasive aspergillosis include abdominal pain, fever, and hematochezia or peritonitis subsequent to bowel ischemia or perforation; typical endoscopic findings include ulcerations or islands of necrotic tissue. Glucocorticosteroids are critical in the management of inflammatory bowel disease (IBD), but are associated with increased risk of opportunistic infections due to immune suppression. It should also be emphasized that IBD itself predisposes to infective complications3Kucharzik T. Ellul P. Greuter T. et al.ECCO guidelines on the prevention, diagnosis, and management of infections in inflammatory bowel disease.J Crohns Colitis. 2021; 15: 879-913Crossref PubMed Scopus (70) Google Scholar and that gastrointestinal infections can be potential triggers for IBD relapse.

Species distribution and antifungal susceptibility patterns of Aspergillus isolates from clinical specimens and soil samples in Mexico.

This is an epidemiological study in Mexico. A. fumigatus was most frequent in clinical specimens and A. niger in soil samples. A. tubingensis and A. tamarii were the most common cryptic species. Resistance to amphotericin B and azoles was 32% each, and 9% for caspofungin.

Potency of olorofim (F901318) compared to contemporary antifungal agents against clinical Aspergillus fumigatus isolates, and review of azole resistance phenotype and genotype epidemiology in China.

Triazole resistance in A. fumigatus is an increasing worldwide problem that causes major challenges in the management of aspergillosis. New antifungal drugs are needed with novel targets, that are effective in triazole-resistant infection. In this study, we retrospectively evaluated potency of the novel drug olorofim compared to contemporary antifungal agents against 111 clinical A. fumigatus isolates collected from Huashan Hospital, Shanghai, China, using EUCAST methodology, and reviewed the literature on triazole resistant A. fumigatus published between 1966 and 2020 in China. Olorofim was active in vitro against all tested A. fumigatus isolates with MIC90 of 0.031mg/L (range 0.008-0.062 mg/L). For 4 triazole-resistant A. fumigatus (TRAF) isolates, the olorofim MIC ranged between 0.016-0.062mg/L. The reported rates of TRAF in China is 2.5% - 5.56% for clinical isolates, and 0-1.4% for environmental isolates.TR34/L98H/S297T/F495I is the predominant resistance mechanism, followed by TR34/L98H. Non TR-mediated TRAF isolates, mostly harboring a cyp51A single point mutation, showed greater genetic diversity than TR-mediated resistant isolates. Resistance due toTR34/L98H and TR34/L98H/S297T/F495I mutations among TRAF isolates might have evolved from separate local isolates in China. Continuous isolation of TRAF in China underscores the need for systematic resistance surveillance as well as the need for novel drug targets such as olorofim.

Fungal Infections of Oral Cavity: Diagnosis, Management, and Association with COVID-19.

The frequency of fungal infections is increasing due to immunodeficiency viruses and immunosuppressive drugs. The most common fungal infection of the oral cavity is candidiasis. The existence of Candida can be a part of normal commensal; hence, the isolation of Candida in the absence of clinical symptoms should exclude candidiasis. The pathogenicity of Candida is witnessed as opportunistic when immune status is compromised. Oral fungal infections are uncommon, but when identified, these infections are associated with greater discomfort and are sometimes destruction of tissues. Cytology and tissue biopsy are helpful in confirming the clinical diagnosis. The management of oral fungal infections must strategically focus on signs, symptoms, and culture reports. This article reviews information on diagnosis and therapeutic management of aspergillosis, cryptococcosis, histoplasmosis, blastomycosis, mucormycosis, and geotrichosis.

Clinicopathological features and management of aspergillosis in some poultry farms in Jos metropolis, Nigeria

Aspergillosis is important in poultry production and human health but difficulty in its ante mortem diagnosis in addition to the unsuccessful outcome of most management options has made the disease a lingering nightmare to farmers. This study presents the clinicopathological features and management of aspergillosis in some poultry farms in Jos metropolis, Nigeria. Thirteen cases of aspergillosis from 12 poultry farms were confirmed and managed from April, 2019 to March, 2020 with 7.6% cases in a mixed turkey-broiler farm, 15.4% in broilers and 76.9% in layers. The ages affected ranged from 3 weeks to 21 weeks with 69.2% cases in pullet grower birds of 10 – 21 weeks compared to young chicks, 3 – 9 weeks with 30.8%. The rainy season accounted for 61.8% cases while mortality ranged from 1.0% to 17.4%. The clinical features were consistent and included dyspnoea; inappetence; retarded growth and mortality. While necropsy showed consolidated lungs with caseous nodules; liver with raised grayish or yellowish irregular nodules; peritonitis with the peritoneum and air sacs laced with caseous nodules; diphtheritic membrane and caseous nodules on intestinal mucosa; haemorrhagic bursitis with granulomata; caseous nodules on osseous tissues as well as nodules on the skin and skeletal muscles. Confirmatory diagnoses of aspergillosis were made by culturing nodules on Sabouraud’s Dextrose Agar. Antifungal susceptibility testing showed CuSO4 to be more susceptible which was used at the dosage of 3g/10L of drinking water for at least 7 days in all the cases. Concurrent bacterial infections were seen in some of the cases and were treated concurrently with antibiotics based on susceptibility testing while farmers using moldy feeds were asked to withdraw such feeds. Conclusively, aspergillosis is prevalent in Jos metropolis with severe impact on production and may be a silent killer disease in poultry due to constraints in diagnosis and its management.
 Keywords: Aspergillosis, clinicopathological features, Jos, management, Nigeria, poultry

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.

Clonal Expansion of Environmental Triazole Resistant Aspergillus fumigatus in Iran.

Azole-resistance in Aspergillus fumigatus is a worldwide medical concern complicating the management of aspergillosis (IA). Herein, we report the clonal spread of environmental triazole resistant A. fumigatus isolates in Iran. In this study, 63 A. fumigatus isolates were collected from 300 compost samples plated on Sabouraud dextrose agar supplemented with itraconazole (ITR) and voriconazole (VOR). Forty-four isolates had the TR34/L98H mutation and three isolates a TR46/Y121F/T289A resistance mechanism, while two isolates harbored a M172V substitution in cyp51A. Fourteen azole resistant isolates had no mutations in cyp51A. We found that 41 out of 44 A. fumigatus strains with the TR34/L98H mutation, isolated from compost in 13 different Iranian cities, shared the same allele across all nine examined microsatellite loci. Clonal expansion of triazole resistant A. fumigatus in this study emphasizes the importance of establishing antifungal resistance surveillance studies to monitor clinical Aspergillus isolates in Iran, as well as screening for azole resistance in environmental A. fumigatus isolates.

A case series of non-valvular cardiac aspergillosis in critically ill solid organ transplant and non-transplant patients and systematic review.

Non-valvular cardiac aspergillosis is a rare infection of the pericardium, myocardium or endocardium and is associated with a high mortality. There is a paucity of reports of non-valvular cardiac aspergillosis in critically ill and solid organ transplant (SOT) patients. The majority of cases have been reported in haemato-oncology patients, some of whom have undergone a bone marrow transplant. We describe four cases affected by non-valvular cardiac aspergillosis in the intensive care setting including a systematic review of this extremely rare infection which is associated with high mortality. All four-patients died but presented with varying clinical, radiological and microbiological evidence of the disease. Three patients presented following complications after solid organ transplantation, two in the context of acute liver failure and emergency liver transplant and one several years after a double lung transplant. The last patient presented with necrotising gall stone pancreatitis, multi-organ failure and subsequently a prolonged intensive care unit (ICU) stay. On review of the literature, January 1955 to July 2019, 45 cases were identified, with different risk factors, clinical and radiological manifestations, treatment regimen and outcome. Antemortem diagnosis of cardiac aspergillosis is difficult and rare, with no cases reporting positive blood culture results. Galactomannan serology has poor sensitivity in solid organ transplant patients, further reduced by prophylactic antimicrobial treatment, which is common in the ICU setting especially post-transplant patients. Due to the scarcity of cases, treatment is extrapolated from invasive aspergillosis management, with emphasis on early treatment with combination therapy.

Screening for triazole resistance in clinically significant Aspergillus species; report from Pakistan

BackgroundBurden of aspergillosis is reported to be significant from developing countries including those in South Asia. The estimated burden in Pakistan is also high on the background of tuberculosis and chronic lung diseases. There is concern for management of aspergillosis with the emergence of azole resistant Aspergillus species in neighbouring countries in Central and South Asia.Hence the aim of this study was to screen significant Aspergillus species isolates at the Microbiology Section of Aga Khan Clinical Laboratories, Pakistan, for triazole resistance.MethodsA descriptive cross-sectional study, conducted at the Aga Khan University Laboratories, Karachi, from September 2016–May 2019. One hundred and fourteen, clinically significant Aspergillus isolates [A. fumigatus (38; 33.3%), A. flavus (64; 56.1%), A. niger (9; 7.9%) A. terreus (3; 2.6%)] were included. The clinical spectrum ranged from invasive aspergillosis (IA) (n = 25; 21.9%), chronic pulmonary aspergillosis (CPA) (n = 58; 50.9%), allergic bronchopulmonary aspergillosis (ABPA) (n = 4; 3.5%), severe asthma with fungal sensitization (SAFS) (n = 4; 3.5%), saprophytic tracheobronchial aspergillosis (n = 23; 20.2%). Screening for triazole resistance was performed by antifungal agar screening method. The minimum inhibitory concentration (MIC) of 41 representative isolates were tested and interpreted according to the Clinical and Laboratory Standards Institute broth microdilution method.ResultsAll the isolates were triazole-susceptible on agar screening. MICs of three azole antifungals for 41 tested isolates were found to be ≤1 ml/L; all isolates tested were categorized as triazole-susceptible, including 4 isolates from patients previously on triazole therapy for more than 2 weeks. The minimum inhibitory concentration required to inhibit the growth of 90% organisms (MIC90) of itraconazole, voriconazole and posaconazole of the representative Aspergillus isolates was 1 mg/L, 1 mg/L and 0.5 mg/L, respectively.ConclusionTriazole resistance could not be detected amongst clinical Aspergillus isolates from the South of Pakistan. However, environmental strains remain to be tested for a holistic assessment of the situation. This study will set precedence for future periodic antifungal resistance surveillance in our region on Aspergillus isolates.

Identification of Fungal Species and Detection of Azole-Resistance Mutations in the Aspergillus fumigatus cyp51A Gene at a South Korean Hospital

PurposeWith changing fungal epidemiology and azole resistance in Aspergillus species, identifying fungal species and susceptibility patterns is crucial to the management of aspergillosis and mucormycosis. The objectives of this study were to evaluate performance of panfungal polymerase chain reaction (PCR) assays on formalin-fixed paraffin embedded (FFPE) samples in the identification of fungal species and in the detection of azole-resistance mutations in the Aspergillus fumigatus cyp51A gene at a South Korean hospital.Materials and MethodsA total of 75 FFPE specimens with a histopathological diagnosis of aspergillosis or mucormycosis were identified during the 10-year study period (2006–2015). After deparaffinization and DNA extraction, panfungal PCR assays were conducted on FFPE samples for fungal species identification. The identified fungal species were compared with histopathological diagnosis. On samples identified as A. fumigatus, sequencing to identify frequent mutations in the cyp51A gene [tandem repeat 46 (TR46), L98H, and M220 alterations] that confer azole resistance was performed.ResultsSpecific fungal DNA was identified in 31 (41.3%) FFPE samples, and of these, 16 samples of specific fungal DNA were in accord with a histopathological diagnosis of aspergillosis or mucormycosis; 15 samples had discordant histopathology and PCR results. No azole-mediating cyp51A gene mutation was noted among nine cases of aspergillosis. Moreover, no cyp51A mutations were identified among three cases with history of prior azole use.ConclusionPanfungal PCR assay with FFPE samples may provide additional information of use to fungal species identification. No azole-resistance mediating mutations in the A. fumigatus cyp51A gene were identified among FFPE samples during study period.