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Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM Introduction In-house real-time PCR (qPCR) is increasingly used for the diagnosis of endemic mycoses and diverse assays are in use in specialized laboratories. External quality control is currently lacking. Objective To compare the performance of different molecular detection protocols for the detection of Histoplasma capsulatum and Coccidioides spp. in a multicenter study involving five European laboratories. Methods Two test sample panels were sent to each laboratory which performed the analysis with their in-house assays. Recipients were blinded to sample content. The Histoplasma-panel included 14 samples representing a range of concentrations of Histoplasma DNA (n = 7), as well as a negative control and DNA from other fungi to test for specificity (Paracoccidioides lutzii n = 1; Blastomyces dermatitidis n = 1; Aspergillus fumigatus n = 1; Emergomyces spp. n = 2, and Candida albicans n = 1). The Coccidioides-panel included 10 samples representing a range of DNA concentrations of Coccidioides posadasii (n = 6), as well as a negative control and DNA from other fungi to test specificity (Uncinocarpus reesii n = 1; Trichophyton violaceum n = 1; and Candida albicans n = 1). Regarding techniques used, four laboratories used Histoplasma qPCRs, and one laboratory a conventional PCR and a broad-range PCR (brPCR) for fungal DNA. Four laboratories used different Coccidioides qPCRs and one laboratory a brPCR to detect Coccidioides DNA. Results Concerning the Histoplasma panel, qPCR assays were the most sensitives and agreement in the lowest detected amount of Histoplasma DNA was very suitable, ranging from 1 pg to 4 pg [ Conclusion Specific protocols based on qPCR showed better sensitivity than conventional and brPCR. These methods are useful for the rapid and sensitive detection Histoplasma and Coccidioides. Application of these tests on clinical samples may speed up diagnosis and potentially limit laboratory exposure to these fungi. Comparisons of in-house tests are essential to assess the performance and detect potential cross-reactivities and achieve a consensus.

Background Although most bloodstream yeast infections are caused by Candida spp., infections by rare or less common species have increased in recent years. Diagnosis of infections caused by these species is difficult due to the lack of specific symptoms and adequate diagnostic tools. Cases presentation We describe two cases of fungemia by Rhodotorula mucilaginosa within a few months of each other, in a secondary Spanish hospital. In both cases, diagnosis was challenging. Blood subcultures in conventional fungal media were persistently negatives and the use of non-conventional fungal media was essential for isolating the yeasts and achieving a correct diagnosis. 1–3 beta-d-glucan detection and a panfungal PCR assay were helpful techniques to confirm the diagnosis Conclusion It is highly important to establish an early diagnosis for fungemia. The process is challenging because often non-specific symptoms are presents. When yeasts grow in blood cultures other genera than Candida spp. could be the cause of infection. Patient risk factors should be assessed to incorporate alternative culture media and the available rapid diagnostic test, in order to provide an early recognition of the pathogen.

Opportunistic fungal pneumonias (OFP) are the main cause of death in AIDS patients worldwide. Diagnosis of these infections is often late as tuberculosis (TB) is frequently the first suspicion. In addition, diagnostic tools have limitations and are unavailable in disadvantaged regions. To perform the differential diagnosis of the main fungi causing OFP in AIDS patients (Histoplasma capsulatum, Cryptococcus neoformans/C. gattii and Pneumocystis jirovecii) vs. the Mycobacterium tuberculosis complex (MTBC), two new assays were developed: (i) a multiplex real-time PCR (MRT-PCR) and (ii) a simple and cost-effective method based on real-time PCR and the analysis of melting curves after amplification (MC-PCR). Both of the techniques were optimized and standardized "in vitro", showing a suitable reproducibility (CV ranged between 1.84 and 3.81% and 1.41 and 4.83%, respectively), a 100% specificity and detection limits between 20 and 2 fg of genomic DNA per 20 µL of reaction. A validation study was performed by retrospectively using 42 clinical samples from 37 patients with proven fungal infection or TB, and 33 controls. The overall sensitivity for the MRT-PCR assay and the MC-PCR assay was 88% and 90.4%, respectively. Both techniques were fast, sensitive and reproducible, allowing for the detection of these pathogens and the performance of a differential diagnosis. This work was supported by research projects PI14CIII/00045 and PI17CIII/00033 from Spanish Fondo de Investigaciones Sanitarias of the Instituto de Salud Carlos III. L.B-M. has a contract supported by the Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, cofinanced by the European Development Regional Fund (EDRF) “A Way to Achieve Europe” and the Spanish Network for the Research in Infectious Diseases (REIPI; RD16/CIII/0004/0003). A.C.M-A had a short fellowship from Fundación Carolina (call 2017–2018). Sí

International audience; The global burden of the endemic mycoses (blastomycosis, coccidioidomycosis, emergomycosis, histoplasmosis, paracoccidioidomycosis, sporotrichosis, and talaromycosis) continues to rise yearly and these infectious diseases remain a leading cause of patient morbidity and mortality worldwide. Management of the associated pathogens requires a thorough understanding of the epidemiology, risk factors, diagnostic methods and performance characteristics in different patient populations, and treatment options unique to each infection. Guidance on the management of these infections has the potential to improve prognosis. The recommendations outlined in this Review are part of the "One World, One Guideline" initiative of the European Confederation of Medical Mycology. Experts from 23 countries contributed to the development of these guidelines. The aim of this Review is to provide an up-to-date consensus and practical guidance in clinical decision making, by engaging physicians and scientists involved in various aspects of clinical management.

A new and easy polymerase chain reaction (PCR) multiplex strategy, for the identification of the most common fungal species involved in invasive fungal infections (IFI) was developed in this work. Two panels with species-specific markers were designed, the Candida Panel for the identification of Candida species, and the Filamentous Fungi Panel for the identification of Aspergillus species and Rhizopusarrhizus. The method allowed the correct identification of all targeted pathogens using extracted DNA or by colony PCR, showed no cross-reactivity with nontargeted species and allowed identification of different species in mixed infections. Sensitivity reached 10 to 1 pg of DNA and was suitable for clinical samples from sterile sites, with a sensitivity of 89% and specificity of 100%. Overall, the study showed that the new method is suitable for the identification of the ten most important fungal species involved in IFI, not only from positive blood cultures but also from clinical samples from sterile sites. The method provides a unique characteristic, of seeing the peak in the specific region of the panel with the correct fluorescence dye, that aids the ruling out of unspecific amplifications. Furthermore, the panels can be further customized, selecting markers for different species and/or resistance genes., This work was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145- FEDER-007569) funded by national funds through the FCT I.P., by the ERDF through the COMPETE2020, by the strategic programme UID/BIA/04050/2019 funded by national funds through the FCT I.P., and co-founded by FEDER through Programa Operacional Regional do Norte, in the scope of the project U. Norte Inova. Joana Carvalho-Pereira was funded by FCT/Ministério da Educação e Ciência, grant number SFRH/BD/113384/2015. The authors confirm independence from the sponsors; the content of the article has not been influenced by the sponsors.

The isolation of the pathogenic fungus Histoplasma capsulatum from cultures together with the visualization of typical intracellular yeast in tissues are the gold standard methods for diagnosis of histoplasmosis. However, cultures are time-consuming, require level 3 containment and experienced personnel, and usually call for an additional confirmation test. Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-ToF MS) has been established as a suitable tool for microbial identification in several clinical laboratories. A reference database has been constructed for the identification of H. capsulatum by MALDI-ToF MS by using six H. capsulatum strains previously identified by molecular methods. For validation, 63 fungal strains belonging to the Collection of the Spanish National Centre for Microbiology were tested against the new reference database combined with other commercial and in-house databases. In a blind assay, all H. capsulatum strains (n = 30) were correctly identified by the database and 86.6% had scores above 1.7. Considering both phases of the fungus for the same strain, the most reliable results were obtained with the mycelial phase, with only 13.3% of isolates having scores below 1.7. The new database was able to identify both morphological phases of the fungus. MALDI-ToF technology yields a prompt and simple identification from H. capsulatum yeast forms and early mycelial cultures. It allows for reducing response time and decreasing risk in fungus manipulation.

Onychomycosis (OM) is a nail infection caused mainly by dermatophyte species but other species of yeast and moulds are frequently involved as well. Classical diagnosis has limitations thus empirical treatment is common. The usefulness of different real time PCR (RT-PCR) assays for identifying species causing OM was assessed in samples from seventy patients and fifteen controls. Conventional methods and four different RT-PCR assays were used: a panfungal, a pandermatophyte and two specific assays for detecting Candida spp. and Aspergillus spp. Fungal elements were visualised in 58% of the samples, and 54% of cultures were positive. Panfungal and pandermatophyte RT-PCR were positive in 28% and 60%, respectively, and the sensitivity relative to positive cultures was 47% and 90%. Candida spp. were detected in 76% of samples analysed and Aspergillus spp. in 60%. These species were also present in 80% of control cases. In conclusion, molecular techniques were useful but showed limitations. The panfungal assay showed a low sensitivity, the pandermatophyte assay was sensitive and specific but did not allow for differentiation among species of dermatophytes. Finally, the role of non-dermatophyte species detected by using specific RT-PCR techniques should be carefully analysed as these species were also present in healthy nails.

Introduction A steroid-immunosuppressed rat model of invasive pulmonary aspergillosis was use to examine the usefulness of galactomannan enzyme immunoassay (GM) and quantitative real time PCR (RT-PCR) in evaluating the association between response and exposure after a high dose of prophylactic posaconazole. Methods Two different strains of Aspergillus fumigatus with different in vitro posaconazole susceptibility were used. Results Serum concentrations demonstrated similar posaconazole exposure for all treated animals. However, response to posaconazole relied on the in vitro susceptibility of the infecting strain. After prophylaxis, galactomannan index and fungal burden only decreased in those animals infected with the most susceptible strain. Conclusion This study demonstrated that both biomarkers may be useful tools for predicting efficacy of antifungal compounds in prophylaxis.

Introduction: The rapid and correct identification of pathogenic species is crucial for several reasons that differ according to the area of interest. In clinical laboratories it is important since knowing the pathogen guides appropriate treatment, dose and duration of therapy. In clinical microbiology laboratories culture and microscopic examination remain the “gold standard”. Biochemical and mass spectometry identification systems, such as the Vitek systems (BioMerieux®) or MALDI-TOF are examples of commercial systems for microbial identification with the advantage of being semi automatic. However, these methods are based on the regrowth and isolation of the microorganism from samples, which in some cases, such as from blood, is time consuming and the success rate of cultivation can be as low as 20%. Recently, several techniques based on the polymerase chain reaction (PCR) have been developed for microbial pathogenic detection and identification particularly Real-Time PCR methods. In this study we developed an alternative PCR based method for the detection of fungal pathogens involved in systemic infections. This is a multiplex PCR method that attributes to each species specific amplicon lengths and a fluoresce dye, according to previously design panels, enabling a fast and reproducible co-amplifying of several loci in a single PCR reaction. Materials and methods: First a panel for species identification, combining fluorescence with molecular weight of specific PCR fragments for Candida and Asprgillus was designed. The PCR fragments obtained are then analysed by capillary electrophoresis and GeneScan fragment analysis. This methodology was optimized using DNA extracted from strains previously identified and, in order to optimize the methodology to clinical samples, we also used serum from healthy donors spiked with different concentrations of fungal DNA. Then the method was tested in DNA extracted from different types of clinical samples, including blood, biopsies and bronchoalveolar lavages of patients with invasive fungal infections (IFI). Results: The optimization of the method, by using DNA from known strains belonging to the target species and strains form other species, showed 100% of specificity. The calculated yield from DNA extracted from serum spiked with fungal DNA was of around 80%. This DNA was then used to determine the sensitivity of the technique and results showed that we were able to obtain amplification products within a range of 1 to 10 pg of the total DNA extracted. Results obtained with DNA extracted from samples of IFI patients, showed that we were able to detect the specific fungal species in 75% of the samples. Several optimizations are being performed. Discussion and conclusions: This new methodology is a promising method since interpretation of results is easy, based on presence/absence of a particular peak of the panel, it is fast, accurate and reproducible and due to the design of the identification panel it is able to identify the pathogenic fungal species involved in mixed infections. Several optimizations are being performed to enhance sensitivity of the method., FEDER through the Programa Operacional Regional Norte, Project U. Norte Inova. JCarvalhoPereira acknowledges FCT for the SFRH/BD/113384/2015 Grant

A molecular diagnostic technique based on real-time PCR was developed for the simultaneous detection of three of the most frequent causative agents of fungal opportunistic pneumonia in AIDS patients: Pneumocystis jirovecii , Histoplasma capsulatum , and Cryptococcus neoformans / Cryptococcus gattii . This technique was tested in cultured strains and in clinical samples from HIV-positive patients. The methodology used involved species-specific molecular beacon probes targeted to the internal transcribed spacer regions of the rDNA. An internal control was also included in each assay. The multiplex real-time PCR assay was tested in 24 clinical strains and 43 clinical samples from AIDS patients with proven fungal infection. The technique developed showed high reproducibility ( r 2 of >0.98) and specificity (100%). For H. capsulatum and Cryptococcus spp., the detection limits of the method were 20 and 2 fg of genomic DNA/20 μl reaction mixture, respectively, while for P. jirovecii the detection limit was 2.92 log 10 copies/20 μl reaction mixture. The sensitivity in vitro was 100% for clinical strains and 90.7% for clinical samples. The assay was positive for 92.5% of the patients. For one of the patients with proven histoplasmosis, P. jirovecii was also detected in a bronchoalveolar lavage sample. No PCR inhibition was detected. This multiplex real-time PCR technique is fast, sensitive, and specific and may have clinical applications.

The performance of a pan-fungal PCR-based technique was evaluated to assess the aetiology of invasive fungal diseases (IFDs). A total of 89 formalin-fixed paraffin-embedded biopsy samples from 84 patients with proven IFD were studied. Culture of tissue was performed in 68 (81%) patients. The sensitivities of the PCR-based technique and microbiological culture of tissues were 89% and 56%, respectively (p

Pneumocystis jirovecii is an unculturable fungus and the causative agent of Pneumocystis pneumonia, a life-threatening opportunistic infection. Although molecular diagnosis is often based on the detection of mtLSU rRNA mitochondrial gene, the number of copies of mitochondrial genes had not been investigated. We developed and optimized six real-time PCR assays in order to determine the copy number of four mitochondrial genes (mtSSU rRNA, mtLSU rRNA, NAD1, and CYTB) in comparison to nuclear genome (DHPS and HSP70) and tested 84 bronchoalveolar fluids of patients at different stages of the infection. Unexpectedly, we found that copy number of mitochondrial genes varied from gene to gene with mtSSU rRNA gene being more represented (37 copies) than NAD1 (23 copies), mtLSU rRNA (15 copies) and CYTB (6 copies) genes compared to nuclear genome. Hierarchical clustering analysis (HCA) allowed us to define five major clusters, significantly associated with fungal load (p = 0.029), in which copy number of mitochondrial genes was significantly different among them. More importantly, copy number of mtLSU rRNA, NAD1, and CYTB but not mtSSU rRNA differed according to P. jirovecii physiological state with a decreased number of copies when the fungal load is low. This suggests the existence of a mixture of various subspecies of mtDNA that can harbor different amplification rates. Overall, we revealed here an unexpected variability of P. jirovecii mtDNA copy number that fluctuates according to P. jirovecii's physiological state, except for mtSSU that is the most stable and the most present mitochondrial gene. This work was supported by research project PI14CIII/00045 from the Spanish Fondo de Investigaciones Sanitarias of the Instituto de Salud Carlos III. CV is supported by research fellowships from the Fondo de Investigaciones Sanitarias of the Spanish Ministry of Economy and Competitiveness (FI12/00095). Sí

The diagnosis of invasive fungal infections (IFIs) is usually based on the isolation of the fungus in culture and histopathological techniques. However, these methods have many limitations often delaying the definitive diagnosis. In recent years, molecular diagnostics methods have emerged as a suitable alternative for IFI diagnosis. When there is not a clear suspicion of the fungus involved in the IFI, panfungal real-time PCR assays have been used, allowing amplification of any fungal DNA. However, this approach requires subsequent amplicon sequencing to identify the fungal species involved, increasing response time. In this work, a new panfungal real-time PCR assay using the combination of an intercalating dye and sequence-specific probes was developed. After DNA amplification, a melting curve analysis was also performed. The technique was standardized by using 11 different fungal species and validated in 60 clinical samples from patients with proven and probable IFI. A melting curve database was constructed by collecting those melting curves obtained from fungal species included in the standardization assay. Results showed high reproducibility (coefficient of variation [CV] < 5%; r > 0.95) and specificity (100%). The overall sensitivity of the technique was 83.3%, with the group of fungi involved in the infection detected in 77.8% of the positive samples with IFIs covered by molecular beacon probes. Moreover, sequencing was avoided in 67.8% of these “probe-positive” results, enabling report of a positive result in 24 h. This technique is fast, sensitive, and specific and promises to be useful for improving early diagnosis of IFIs.

Histoplasmosis and paracoccidioidomycosis are emerging infections in Spain associated with immigration and travelling. In last three decades a total of 128 cases of histoplasmosis have been reported in Spain, 59 in travellers, 63 in immigrants, three associated to drug abuse, two in laboratory workers, and one in a solid organ transplant receptor. In 1969 the first Spanish case of paracoccidioidomycosis was published and a total of 21 cases have been reported so far. Those patients suffered from the chronic form of the disease with period of latency as long as 50 years. Other endemic mycoses such as blastomycosis, coccidioidomycosis, lobomycosis, pythiosis and sporotrichosis have not increased in frequency. Microbiological cultures of endemic fungi must be handled in facilities which comply with international biosafety regulations and must also be taken into account for cultures from patients with suspected endemic mycosis.

A duplex Real Time PCR (RT-PCR) assay for detecting DNA of members of the genus Fusarium has been developed and validated by using two mouse models of invasive infection. The duplex RT-PCR technique employed two specific molecular beacon probes targeting a highly conserved region of the fungal rDNA gene. This technique showed a detection limit of 10 fg DNA per μl of sample and a specificity of 100%. The sensitivity in a total of 48 samples from a murine model of Fusarium solani infection was 93.9% for lung tissues and 86.7% for serum samples. In comparison, the sensitivity in a total of 45 samples of a F. oxysporum murine model infection was 87% for lung tissues and 42.8% for serum samples. This molecular technique could be a reliable method for the quantification and the evaluation of the disease in animal models and for the clinical diagnosis of fusariosis.

The performance of a real-time PCR-based assay was retrospectively analyzed (according to European Organization for Research and Treatment of Cancer/Mycosis Study Group criteria) in the samples of patients with invasive aspergillosis. A total of 711 serial samples (356 whole-blood and 355 serum samples) from 38 adult patients were analyzed. The Aspergillus fumigatus PCR assay results were positive for 89 of 356 (25%) whole-blood samples and 90 of 355 (25.35%) serum samples. Positive PCR results were seen in 29 of 31 (93.5%) patients for which serum was analyzed and in 31 of 33 (93.9%) cases with whole-blood specimens. Both blood and serum samples were available in 26 cases, and significant differences were not observed in this subgroup of cases. The average number of threshold cycles ( C T ) for positive blood samples was 37.6, and the average C T for serum was 37.4. The DNA concentration ranged between 2 and 50 fg per μl of sample, with average DNA concentrations of 10.2 and 11.7 fg in positive blood and serum samples, respectively ( P > 0.01). The performance of this PCR-based quantitative assay was similar for both serum and blood samples. We recommend serum samples as the most convenient hematological sample to use for Aspergillus DNA quantification when serial determinations are done.

Background. Histoplasmosis and paracoccidioidomycosis (PCM) have increased in Spain in recent years, due firstly to the migration from endemic regions and secondly to travelers returning from these regions. In non-endemic areas, diagnosis of both diseases is hampered by the lack of experience, long silent periods, and the resemblance to other diseases such as tuberculosis and sarcoidosis. Methods. A total of 39 cases of imported histoplasmosis and 6 cases of PCM diagnosed in the Spanish Mycology Reference Laboratory since 2006 were analyzed. Microbiological diagnosis was performed using classical methods and also a specific real-time polymerase chain reaction (RT-PCR) assay for each microorganism. Results. We had 9 cases of probable histoplasmosis in travelers and 30 cases in immigrants, 29 of whom were defined as proven. Paracoccidioidomycosis (PCM) cases were either immigrants or people who had lived for a long period of time in endemic regions, all of whom were classified as proven cases. Cultures showed a good sensitivity in detecting Histoplasma capsulatum in immigrants with proven histoplasmosis (73%); however, growth was very slow. The fungus was never recovered in traveler patients. Paracoccidioides brasiliensis was isolated in a culture only in one case of the proven PCM. Serological methods were not very reliable in immunocompromized patients with histoplasmosis (40%). A PCR-based technique for histoplasmosis detected 55.5% of the cases in travelers (probable cases) and 89% of the cases in immigrants (proven). The PCR method for PCM detected 100% of the cases. Conclusions. These kinds of mycoses are increasingly frequent in non-endemic areas, and newer and faster techniques should be used to reach an early diagnosis. The RT-PCR techniques developed appear to be sensitive, specific, and fast and could be helpful to detect those mycoses. However, it is also essential that physicians perform differential diagnosis in individuals coming from endemic areas.

An increase in immigration from endemic regions has resulted in a number of cases of paracoccidioidomycosis (PCM) being imported into Spain. A molecular diagnostic technique based on real-time PCR was developed for the detection of Paracoccidioides brasiliensis DNA in both culture and patients' clinical samples. A Molecular Beacon probe was used, labelled with FAM and directed at the ITS1 region of ribosomic DNA. The detection limit of the technique developed was 1 fg of fungal DNA per microl of sample. This procedure proved to be very reproducible and specific. The technique was tested with cultures of 12 clinical strains and on samples from two patients with proven PCM. Real-time PCR was positive for all the culture strains, as well as those from both patients. By samples, the technique was positive in sputum and tissue biopsies but less useful on blood samples. Samples were analyzed several months after patient treatment, detecting a small amount of fungal DNA in one respiratory sample. This technique of real-time PCR is a sensitive method for rapid diagnosis of paracoccidioidomycosis and could serve to monitor patients after treatment has begun.

A collection of 2,278 isolates belonging to 86 different fungal species was tested with micafungin and eight other drugs using the EUCAST procedures. Micafungin was active against species of Candida and Aspergillus (even azole-resistant species) as well as Penicillium spp., Scedosporium apiospermum , and Acremonium spp. It was inactive for species of Basidiomycota and Mucorales and for multiresistant species such as those of Fusarium .

A study was designed to assess the reliability of the serial detection of Aspergillus sp. DNA to diagnose invasive aspergillosis (IA) in patients with febrile neutropenia. Two blood and two serum samples were taken weekly from 83 patients. A total of 2,244 samples were analyzed by real-time quantitative PCR. Twelve (14.4%) patients were diagnosed with IA. Taking two consecutive positive results as the diagnostic criterion, PCR detected 11 cases, with 4 false positives, giving sensitivity, specificity, positive, and negative predictive values of 91.6%, 94.4%, 73.3%, and 98.5%, respectively. On analyzing in conjunction with high-resolution chest tomography (HRCT) and galactomannan (GM) testing, the combination of serial PCR and GM detected 100% of aspergillosis cases, with a positive predictive value of 75.1%. This diagnostic strategy presented, according to CART analysis, a receiver-operator curve with an area under the curve of 0.97 (95% confidence interval, 0.895 to 1.032; P < 0.01), with a relative risk of IA 6.92 times higher than the control population and with predictive success of 95.2%. As regards early diagnosis, the serial detection of Aspergillus DNA took on average 21 days less than HRCT and 68 days less than GM. The serial detection of Aspergillus DNA using real-time quantitative PCR has great diagnostic applicability, which increases when combined with GM quantification.

In recent years, the most important advances in the treatment of transplant recipients, patients with haematological neoplasm and critically ill patients have been accompanied by an increase in the incidence of common fungal diseases and the emergence of some less common ones. Although new techniques (e.g. galactomannan detection) and new antifungals have appeared, these opportunistic infections remain difficult to diagnose and have a high mortality. New diagnostic techniques could improve this outlook, although they are far from becoming available in daily practice.

Activities of 35 combinations of antifungal agents against Scedosporium spp. were analyzed by a checkerboard microdilution design and the summation of fractional concentration index. An average indifferent effect was detected apart from combinations of azole agents and echinocandins against Scedosporium apiospermum . Antagonism was absent for all antifungal combinations against both species.

Histoplasmosis is an infection that occurs when conidia of the dimorphic fungus Histoplasma capsulatum var capsulatum are inhaled into the lungs. It is the most common systemic mycosis diagnosed among European travelers returning from endemic areas of Central and South America, 1–3 and in recent years, a growing number of cases, both isolated and in clusters, have been detected in nonendemic areas such as Europe. 4–7 This rise in apparent cases of histoplasmosis is thought to be a result of increased international travel, especially tourism, cooperation, and trade. However, heightened awareness of the clinical manifestations and epidemiology of histoplasmosis by health care practitioners in these countries may have also played a part in increasing diagnosis. Published data have undoubtedly underestimated the true magnitude of this travel‐related mycosis (as well as other geographically restricted endemic mycoses such as coccidiomycosis, paracoccidioidomycosis, and penicilliosis), and many cases, especially those asymptomatic or presenting as a mild nondescript febrile illness, often go undiagnosed. Most cases of imported histoplasmosis are known to occur in small clusters with a common source of infection. Usually, the individuals affected in these outbreaks have a history of participation in leisure and work activities, which involve heavy exposure to bat or bird droppings (mostly cavers and volunteers with recent involvement in cleaning tasks or rehabilitation of old buildings). 8–12 More than 95% of immunocompetent people remain asymptomatic following low‐inoculum infection with H capsulatum . 2 In the few symptomatic cases which occur, clinical presentation includes a self‐limited benign pulmonary illness with fever, malaise, dry cough, and chest pain. Disseminated severe disease is only observed in those individuals with a high degree of prior exposure to guano or impaired cellular immunity. 6,13,14 Here, we describe an outbreak of acute histoplasmosis with unusual clinical manifestations among four previously healthy Spanish travelers who had …

Objetivos Valoracion de la utilidad de una tecnica de reaccion en cadena de la polimerasa (PCR) cuantitativa en tiempo real (PCR-TR) para el diagnostico de histoplasmosis en muestras clinicas. Metodos Para el diseno de los iniciadores y de las sondas se analizaron las secuencias de las regiones ITS (internal transcriber spacers) del ADN ribosomico de 20 cepas de Histoplasma capsulatum. Se empleo la tecnologia LightCycler (Roche Applied Science) y la sonda fue disenada mediante el sistema Fluoresce Resonance Energy Transfer (FRET). Se realizaron estudios de reproducibilidad, sensibilidad y especificidad. Ademas, se incluyo un sistema de control interno para reconocer falsos negativos por inhibicion de la reaccion de PCR. Tras ello, se testo la tecnica en 22 muestras clinicas procedentes de 14 pacientes diagnosticados de histoplasmosis probada. Ademas se analizaron 30 muestras de control, procedentes de enfermos con otras micosis, de pacientes con neutropenia febril y de voluntarios sanos. Resultados El limite de deteccion de la tecnica fue de 1 fg de ADN fungico por μl de muestra. Asi mismo fue reproducible y muy especifica. La tecnica fue positiva en 11 de los 14 enfermos (78,6%) y en 17 de las 22 muestras analizadas (77,3%). Por muestras, el 100% de las muestras respiratorias y de los aspirados de medula osea fueron positivos, pero solo el 70% de los sueros (p Conclusion Esta tecnica de PCR-TR es un metodo sensible y especifico para el diagnostico rapido de histoplasmosis, sobre todo en muestras respiratorias y aspirados de medula osea. La sensibilidad en suero es inferior, pero puede ser complementaria al cultivo y a la serologia en enfermos VIH positivos.

Aspergillus fumigatus is the most common mold involved in human infections. However, the number of non-fumigatus species able to cause disease is continuously increasing. Among them, Aspergillus lentulus is reported in hematological and cystic fibrosis patients and in those treated with corticosteroids. A. lentulus differs from A. fumigatus in some clinically relevant aspects such as virulence and antifungal susceptibility, showing high MICs to most antifungals. Previous studies proved that A. lentulus was pathogenic in immunocompromised mice, although the course of the infection was delayed compared to A. fumigatus. These differences could explain why A. lentulus is mostly found in mixed infections with A. fumigatus challenging the diagnosis and treatment. We used the alternative model host Galleria mellonella to compare virulence, host interaction, fungal burden and antifungal response when larvae were infected with A. fumigatus or A. lentulus alone, and with a mixture of both species. A. lentulus was pathogenic in G. mellonella but infected larvae did not respond to therapeutic doses of voriconazole. We were able to simultaneously detect A. fumigatus and A. lentulus by a multiplex Nested Real Time PCR (MN-PCR). Comparative analysis of larvae histological sections showed melanization of both species but presented a different pattern of immune response by haemocytes. Analysis of fungal burden and histology showed that A. lentulus survived in the G. mellonella despite the antifungal treatment in single and mixed infections. We conclude that the simultaneous presence of antifungal susceptible and resistant Aspergillus species would likely complicate the management of these infections. EM was supported by Fondo de Investigacion Sanitaria (FIS:PI12_02376). LA-F was funded by Fondo de Investigación Sanitaria with a Miguel Servet fellowship (FIS:CP11/00026). Sí

Objetivos Valoracion de la utilidad de un metodo de reaccion en cadena de la polimerasa (PCR) en tiempo real para la deteccion y cuantificacion del ADN fungico en un modelo murino de aspergilosis pulmonar. Metodos El modelo murino se realizo con ratones machos ICR libres de patogenos. Los animales se dividieron en grupos, se inmunodeprimieron y se inocularon intranasalmente con diferentes concentraciones de conidias (10 6 , 10 5 , 10 4 y 10 3 conidias/ml) de una cepa clinica de Aspergillus fumigatus . Los animales fueron sacrificados cuando se detectaron sintomas de aspergilosis pulmonar. Se extrajeron los pulmones para cultivo y deteccion de ADN fungico mediante PCR en tiempo real, con dos iniciadores que amplifican una region del ADN ribosomico de Aspergillus spp. Se calcularon el tiempo de supervivencia por grupo de experimentacion y los coeficientes de correlacion con el recuento de colonias y los resultados de la PCR. Resultados El tiempo medio de supervivencia se asocio significativamente con el tamano del inoculo empleado. El 90% de los animales mostro un recuento positivo de colonias de A. fumigatus en el tejido pulmonar, pero el numero de colonias cultivadas no se asocio significativamente con los dias de supervivencia ni con la cantidad de conidias inoculadas. La PCR en tiempo real fue positiva en el 100% de los ratones asociandose significativamente (p Conclusion La PCR en tiempo real constituye un metodo fiable para cuantificar y evaluar la infeccion pulmonar por A. fumigatus en modelo animales.

Adiaspiromycosis is primarily a necrotizing granulomatous pneumonia caused by a dimorphic fungus of the genus Emmonsia. A young crested porcupine (Hystrix cristata) found dead showed multiple fractures, chronic pleuritis, and granulomatous pneumonia. Microscopically, cystic structures were consistent with adiaspiromycosis by Emmonsia crescens. The diagnosis was confirmed using molecular methods.

African histoplasmosis, caused by Histoplasma capsulatum var. duboisii, is endemic in Africa. The disease usually involves the skin, subcutaneous tissue, and bones. A case of African histoplasmosis presenting as a cutaneous tumor and non-healing wound in a 66-year-old immunocompetent male residing in Africa, the first ever reported following mudbaths and acupuncture, is hereby reported. Diagnosis was confirmed by means of polymerase chain reaction performed on tissue material. The patient was started on long-term itraconazole therapy and he responded well. African histoplasmosis should be included in the differential diagnosis of non-healing wounds or tumor-like lesions, especially in the context of mudbaths in an endemic area.

Background New techniques, such as those based on multiplex quantitative real-time PCR (MRT-PCR), can improve the detection of invasive candidiasis (IC). Methods We prospectively studied 63 intensive care unit patients with suspected IC and 40 healthy controls. Blood cultures and MRT-PCR were performed at day 0 and +2, +7, +14 and +21 days in all patients. In addition, β-d-glucan (BDG) and Candida albicans germ tube antibody (CAGTA) were quantified. Results IC was confirmed in 27 patients. Colonization was significantly higher in patients with IC (96% versus 64%, P = 0.002). The sensitivity, specificity, positive predictive value and negative predictive value of MRT-PCR for the diagnosis of IC were 96.3%, 97.3%, 92.8% and 98.7%, respectively. The positive predictive value and specificity were significantly higher for MRT-PCR than for BDG and CATGA. MRT-PCR performed very well, especially in deep-seated IC (sensitivity 90.9% versus 45.4% for blood culture; P = 0.06). As regards the most appropriate clinical sample for DNA amplification, in this study whole blood and serum presented similar results. Conclusions MRT-PCR appears to be a useful test for confirming a diagnosis of IC in critically ill patients, especially in those with deep-seated disease. Its high sensitivity and positive predictive value make it a much more efficient tool for the management of IC than other diagnostic procedures and clinical scores.

The epidemiology of Candida parapsilosis and the closely related species C. orthopsilosis and C. metapsilosis has changed in recent years, justify the need to identify this complex at the species level. In this study we investigate the intergenic spacer 1 (IGS1) of the ribosomal DNA (rDNA) to evaluate the utility of this gene region as a phylogenetic molecular marker and the suitability of a high-resolution melting (HRM) strategy based on this region for identification of members of the C. parapsilosis spp. complex. We sequenced the IGS1 and the internal transcribed spacer (ITS) regions of the rDNA from 33 C. parapsilosis sensu lato strains. Although both regions are useful in identifying species, comparative sequence analysis showed that the diversity in the IGS1 region was higher than in the ITS sequences. We also developed an HRM analysis that reliably identifies C. parapsilosis spp. complex based on the amplification of 70 bp in the IGS1 region. All isolates were correctly identified with a confidence interval >98%. Our results demonstrate that HRM analysis based on the IGS1 region is a powerful tool for distinguishing C. parapsilosis from cryptic species.

A retrospective analysis of real-time PCR (RT-PCR) results for 151 biopsy samples obtained from 132 patients with proven invasive fungal diseases was performed. PCR-based techniques proved to be fast and sensitive and enabled definitive diagnosis in all cases studied, with detection of a total of 28 fungal species.

Organ transplant recipients under immunosuppressive therapy have a highly increased risk of opportunistic fungal infections. Cutaneous infection caused by Alternaria species are relatively rare in humans and most cases reported in the literature are in immunocompromised individuals. We report here on a 33-year old male renal transplant patient with diabetes mellitus who presented with cutaneous alternariosis caused by Alternaria infectoria, two years after the transplant. The diagnosis was performed by real-time polymerase chain reaction assay and histopathologic examination. The extension of the lesion under itraconazole treatment required treatment consisting of a combination of surgical excision and liposomal amphotericin B.

A new real-time polymerase chain reaction (RT-PCR) assay based on a Coccidioides genus–specific molecular beacon probe was developed for the detection of coccidioidomycosis and validated with tissues from animal models and clinical samples. The assay showed high analytic reproducibility (r 2 > 0.99) and specificity for cultured strains (100%); the lower limit of detection was 1 fg of genomic DNA/μL of reaction. Fungal burdens in the organs of mice infected with Coccidioides posadasii strain Silveira were more accurately quantified by RT-PCR compared to colony-forming unit for all tissues. The RT-PCR assay was positive for 97.7% of spleen and 100% of liver or lung. Progression of infection in all organs was similar by both methods ( P > 0.05). The sensitivity of the assay also was 100% for paraffin-embedded samples and samples from patients with positive cultures. Our RT-PCR assay is effective for the diagnosis and monitoring of Coccidioides infection, and its use also avoids the biohazard and time delay of identifying cultures in the clinical setting.

The activities of 10 combinations of antifungal agents against 25 clinical isolates of Scopulariopsis brevicaulis were tested by the checkerboard technique. An average indifferent effect was detected for all combinations. Synergy was observed for some isolates and combinations, particularly with posaconazole-terbinafine (68% of strains), amphotericin B-caspofungin (60%), and posaconazole-caspofungin (48%).

Background Several genotyping protocols have been described to study Candida albicans strains with different sensitivity values. In this study we have analyzed the genetic relatedness and the antifungal susceptibility of several Candida albicans strains isolated from a patient who from suffered recurrent candiduria for a period of five years. Strains were genotyped using Microsatellite Length Polymorphism (MLP) with three microsatellite markers (HIS 3, EF 3 and CDC 3), and a new method based on high resolution melting (HRM) was developed to analyze the microsatellite region. This method was compared with the conventional technique that uses capillary electrophoresis. Results MICs of the isolates showed the existence of fluconazole susceptible and resistant strains. An inter-colony test using single concentration (8 and 16 mg/l) of fluconazole revealed the coexistence of both fluconazole susceptible and resistant strains. Both genotyping analysis methods showed that all the patient’s isolates had a clonal origin. HRM analysis method developed was able to accurately establish strain relatedness and presented a discriminatory power of 0.77. Conclusions Although HRM analysis method presented a lower discriminatory power compared to methods based on capillary electrophoresis, it provided a more cost-effective and suitable alternative for genotyping C. albicans in a clinical laboratory.

Background A multicenter study was conducted. A panel containing DNA from Histoplasma capsulatum, as well as negative and cross-reaction controls, was sent to five different laboratories, members of the MICOMOL network from CYTED Program. Aims The objective was to assess the accuracy of different PCR protocols to detect H. capsulatum DNA. Methods Seven different PCR protocols were tested. They were based on PCR techniques and used unicopy and multicopy targets. Results Most of these protocols (4/7) were able to detect the smallest amounts of fungal DNA (102 fg/μl). Overall sensitivity was 86% and specificity was 100%. The protocol based on a unicopy target (SCAR220) presented lower sensitivity (43%) but 100% specificity. The real-time protocols tested were highly reproducible, sensitive, and specific. Neither false positives nor cross-reactions were detected in any protocol. Conclusions All laboratories were able to amplify H. capsulatum DNA, and real-time PCR seems to be a promising tool to efficiently detect this pathogen in clinical samples.

We have developed a two-step method based on high-resolution melting (HRM) that reliably identifies species from the Cryptococcus species complex ( Cryptococcus neoformans var. grubii , Cryptococcus neoformans var. neoformans , and Cryptococcus gattii ). Our results indicate that HRM can provide a fast protocol to identify and distinguish among the main Cryptococcus species.

Background Epidemiological studies worldwide have shown that A. fumigatus exhibits important phenotypic and genotypic diversity, and these findings have been of great importance in improving the diagnosis and treatment of diseases caused by this fungus. However, few studies have been carried out related to the epidemiology of this fungus in Latin America. This study´s aim is to report on the epidemiology of the fungus by analyzing the phenotypic variability of Aspergillus section Fumigati isolates from different Latin American countries and the relationship between this variability, the geographical origin and genotypic characteristics. Methods We analyzed the phenotypic characteristics (macro- and micromorphology, conidial size, vesicles size, antifungal susceptibility and thermotolerance at 28, 37 and 48°C) of A. section Fumigati isolates from Mexico (MX), Argentina (AR), Peru (PE) and France (FR). The results were analyzed using analysis of variance (ANOVA) and Tukey's multiple comparison test to detect significant differences. Two dendrograms among isolates were obtained with UPGMA using the Euclidean distance index. One was drawn for phenotypic data, and the other for phenotypic and genotypic data. A PCoA was done for shown isolates in a space of reduced dimensionality. In order to determine the degree of association between the phenotypic and genotypic characteristics AFLP, we calculated the correlation between parwise Euclidean distance matrices of both data sets with the nonparametric Mantel test. Results No variability was found in the macromorphology of the studied isolates; however, the micromorphology and growth rate showed that the PE isolates grew at a faster rate and exhibited the widest vesicles in comparison to the isolates from MX, AR and FR. The dendrogram constructed with phenotypic data showed three distinct groups. The group I and II were formed with isolates from PE and FR, respectively, while group III was formed with isolates from MX and AR. The dendrogram with phenotypic and genotypic data showed the same cluster, except for an isolate from FR that formed a separate cluster. This cluster was confirmed using PCoA. The correlation between the phenotypic and genotypic data of the isolates revealed a statistically significant association between these characteristics. Conclusions The PE isolates showed specific phenotypic characteristics that clearly differentiate them from the rest of the isolates, which matches the genotypic data. The correlation between the phenotypic and genotypic characteristics showed a statistically significant association. In conclusion, phenotypic and genotypic methods together increase the power of correlation between isolates.

Background: Absence or severe reduction in the amount of ergosterol in the fungal membrane and its replacement with other sterols have been described as potential antifungal resistance mechanisms in fungi. Aims and methods: The ergosterol content in a collection of 51 clinical yeast isolates, including susceptible and resistant strains to amphotericin B and azoles, was estimated by a simple chromatographic method (HPLC-UV). Results: A high content of ergosterol was detected for several strains of Candida glabrata, Candida tropicalis or Pichia membranifaciens. In contrast, strains of Cryptococcus neoformans and Dipodascus capitatus had the lowest ergosterol concentrations. No significant correlation was observed between antifungal susceptibility patterns and ergosterol content. Conclusions: We conclude from this study that ergosterol content on yeasts may not be associated with specific resistant patterns. © 2011 Published by Elsevier Espana, S.L. on behalf of Revista Iberoamericana de Micologia. Perfil de sensibilidad in vitro y contenido en ergosterol en levaduras de origen clinico

The commercial technique Vitek 2 system for antifungal susceptibility testing of yeast species was evaluated. A collection of 154 clinical yeast isolates, including amphotericin B- and azole-resistant organisms, was tested. Results were compared with those obtained by the reference procedures of both the CLSI and the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Two other commercial techniques approved for clinical use, the Etest and the Sensititre YeastOne, were included in the comparative exercise as well. The average essential agreement (EA) between the Vitek 2 system and the reference procedures was >95%, comparable with the average EAs observed between the reference procedures and the Sensititre YeastOne and Etest. The EA values were >97% for Candida spp. and stood at 92% for Cryptococcus neoformans . Intraclass correlation coefficients (ICC) between the commercial techniques and the reference procedures were statistically significant ( P < 0.01). Percentages of very major errors were 2.6% between Vitek 2 and the EUCAST technique and 1.6% between Vitek 2 and the CLSI technique. The Vitek 2 MIC results were available after 14 to 18 h of incubation for all Candida spp. (average time to reading, 15.5 h). The Vitek 2 system was shown to be a reliable technique to determine antifungal susceptibility testing of yeast species and a more rapid and easier alternative for clinical laboratories than the procedures developed by either the CLSI or EUCAST.

Scedosporium apiospermum and Scedosporium prolificans are fungal pathogens that can cause severe human infections, including disseminated mycosis in immunocompromised patients. Two real-time PCR (RT-PCR) assays for the diagnosis of these species were developed and validated for the classification of clinical strains and for the detection of DNA in clinical samples by use of a murine model of invasive infection. A total of 14 clinical strains and 141 samples, including blood, serum, and lung samples from infected CD1 mice, were analyzed. Each RT-PCR methodology used a species-specific molecular beacon probe targeting a highly conserved region of the fungal ribosomal DNA gene. Results showed 100% specificity and a detection limit of 10 fg of DNA for both assays. The sensitivities for the S. prolificans -specific PCR assay were 100% for cultured clinical strains, 95.5% for lung tissues, 85% for serum, and 83.3% for blood. For S. apiospermum , the sensitivities were 100% for clinical strains and 97.2%, 81.8%, and 54.5% for lung tissues, serum, and blood, respectively. Both techniques can be useful for clinical diagnosis, and further studies are warranted.

Evaluation of the usefulness of a quantitative real-time polymerase chain reaction-based (RT-PCR) technique for clinical diagnosis of histoplasmosis.Primers and probes were designed on the basis of sequences from the ITS regions of ribosomal DNA of 20 clinical strains of Histoplasma capsulatum. LightCycler procedures (Roche Applied Science) were used with probes marked by fluorescence resonance energy transfer (FRET). Reproducibility, sensitivity, and specificity were analyzed. In addition, an internal control was designed to identify false negative results by PCR inhibition. The RT-PCR assay was tested in 22 clinical samples from 14 patients with proven histoplasmosis. In addition, 30 samples from patients with febrile neutropenia or mycoses other than histoplasmosis, and from healthy volunteers were analyzed as controls.The limit of detection of the assay was 1 fg of genomic DNA per microl of sample. The PCR-based technique was reproducible and highly specific. Positive results were obtained in 11/14 (78.6%) patients and in 17/22 (77.3%) clinical samples. RT-PCR was positive in 100% of respiratory secretions and bone marrow samples, but only 70% of sera (p0.01). Mean fungal DNA value was 23.1 fg/microl in serum and 4.85 x 10(3) fg/microl in respiratory and bone marrow samples. RT-PCR results were positive in serum from three HIV patients for which antibody detection by immunodiffusion was negative. Specificity was 100%, since PCR results were negative for all the control samples.Thes RT-PCR technique is a sensitive, specific method for early diagnosis of histoplasmosis, particularly when respiratory secretions or bone marrow samples are analyzed. The reliability is lower in serum, but it can be used as an additional, complementary technique to culture and serology in HIV patients.