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1.
The increasing incidence of invasive fungal diseases (IFD), most of all invasive aspergillosis (IA) in immunocompromised patients emphasises the need to improve the diagnostic tools for detection of fungal pathogens. We investigated the diagnostic performance of a multifungal DNA‐microarray detecting 15 different fungi [Aspergillus, Candida, Fusarium, Mucor, Rhizopus, Scedosporium and Trichosporon species (spp.)] in addition to an Aspergillus specific polymerase chain reaction (PCR) assay. Biopsies, bronchoalveolar lavage and peripheral blood samples of 133 immunocompromised patients (pts) were investigated by a multifungal DNA‐microarray as well as a nested Aspergillus specific PCR assay. Patients had proven (n = 18), probable (n = 29), possible (n = 48) and no IFD (n = 38) and were mostly under antifungal therapy at the time of sampling. The results were compared to culture, histopathology, imaging and serology, respectively. For the non‐Aspergillus IFD the microarray analysis yielded in all samples a sensitivity of 64% and a specificity of 80%. Best results for the detection of all IFD were achieved by combining DNA‐microarray and Aspergillus specific PCR in biopsy samples (sensitivity 79%; specificity 71%). The molecular assays in combination identify genomic DNA of fungal pathogens and may improve identification of causative pathogens of IFD and help overcoming the diagnostic uncertainty of culture and/or histopathology findings, even during antifungal therapy.  相似文献   

2.
Invasive aspergillosis (IA) remains difficult to diagnose in immunocompromised patients, because diagnostic EORTC/MSG criteria are often not met. As biomarkers might elucidate the pathogen, we analysed the performance of an Aspergillus PCR assay in blood for diagnosis of IA in immunocompromised paediatric patients with suspected infections. Ninety‐five haemato‐oncological paediatric patients were included over a period of 3 years, the underlying diseases consisting of acute leukaemia, solid tumours, non‐malignant immunocompromising disorders and haematopoietic stem cell transplantation recipients. We retrospectively analysed 253 consecutive episodes of suspected infections. Thirty‐eight patients had possible IA, none of the patients fulfilled EORTC/MSG criteria of probable/proven IA. PCR positivity was observed in 97/967 analyses. Sensitivity, specificity, positive and negative predictive value of the PCR per episode were 34%, 78%, 31% and 81% using possible IA as endpoint. Taken together, an undirected blood screening by Aspergillus‐specific PCR is of little diagnostic value in a heterogenous paediatric patient cohort. Harnessing PCR for diagnosis of IA should thus be focused on blood analyses of more homogenous high‐risk patients and/or analyses of bronchoalveolar lavage, tissue or cerebrospinal fluid specimens.  相似文献   

3.
Invasive aspergillosis (IA) is an important cause of morbidity and mortality in children and adults with haematologic malignancies or undergoing allogeneic haematopoietic stem cell transplantation, and early diagnosis and adequate antifungal treatment improve outcome. However, important differences exist between children and adults regarding epidemiology, underlying disease, and comorbidities, and the value of diagnostic tools to detect IA may also differ between these patient populations. Imaging studies are important to detect IA early, but typical findings of IA in chest computed tomography of adults are not detected in the majority of children. Whereas the value of the serum marker galactomannan seems to be comparable in children and adults, data on the performance of beta‐d ‐glucan in children are too limited for firm conclusions. PCR‐based assays are a promising diagnostic approach to rapidly and reliably detect and identify Aspergillus species in various clinical samples. However, as the majority of data on PCR‐based approaches has been obtained in adult patients, the value of this method in paediatric patients has not been defined to date. The present review focuses on studies of PCR‐based methods to diagnose IA in immunocompromised paediatric patients.  相似文献   

4.
Invasive pulmonary aspergillosis (IPA) is a life‐threatening infection mainly affecting immunocompromised patients. Early diagnosis is critical, but the diagnostic gold standard (histopathology and culture) is time consuming and cannot offer early confirmation of IPA. Fungal biomarkers like galactomannan (GM) are a promising extension to the diagnostic repertoire. However, it still remains under discussion if biomarker analysis from the site of the infection is superior to testing blood samples. We retrospectively evaluated the diagnostic performance of concurrent serum GM and bronchoalveolar lavage (BAL) GM (obtained within 24 h) of immunocompromised patients at high risk of IPA. Twenty‐six proven/probable patients and eight patients with no IPA according to the EORTC/MSG 2008 criteria were included in this study. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic odds ratio were for BAL GM: 85%, 88%, 96%, 64% and 38.5, and for serum GM: 23%, 88%, 88%, 26% and 2.1 respectively. BAL GM proved to be significantly more sensitive for the detection of IPA compared to same‐day serum GM in patients at high risk of IPA (P < 0.0001). Our data show that BAL GM testing is significantly superior to serum GM implying that diagnostic efforts should focus on specimens from the site of infection.  相似文献   

5.
Molecular typing and antifungal susceptibility testing of 34 clinical Serbian Cryptococcus neoformans isolates from 25 patients was retrospectively performed. Amplified fragment length polymorphism (AFLP) fingerprinting was used for genotyping, whereas a novel real‐time PCR was used to determine the mating‐ and serotype. The antifungals amphotericin B, 5‐fluorocytosine, fluconazole, voriconazole, itraconazole and posaconazole were used to determine the antifungal susceptibility profiles. The majority of isolates belonged to genotype AFLP1/VNI (= 20; 58.8%), followed by AFLP2/VNIV (= 10; 29.4%), AFLP3/VNIII (= 3; 8.8%) and AFLP1B/VNII (= 1; 2.9%). All AFLP1/VNI isolates were mating–serotype αA, the sole AFLP1B/VNII isolate was found to be a A, whereas AFLP2/VNIV harboured serotype D isolates with either the a (= 2; 5.9%) or α (= 8; 23.5%) mating‐type allele. The isolates (= 3; 8.8%) that were found to be genotype AFLP3/VNIII had the hybrid mating‐ and serotype combination a A‐αD. In vitro antifungal susceptibility testing showed that all isolates were susceptible to amphotericin B, voriconazole and posaconazole. Low resistance level was observed for fluconazole (= 1; 2.9%) and 5‐fluorocytosine. (= 2; 5.8%). A large percentage of isolates was found to be susceptible dose dependent to itraconazole (= 16; 47.1%). AFLP1/VNI was the most common genotype among clinical C. neoformans isolates from immunocompromised patients in Serbia. C. neoformans from HIV‐negative patients were significantly less susceptible to 5‐fluorocytosine (P < 0.01). Correlation between genotypes and antifungal susceptibility was not observed.  相似文献   

6.
Autopsy studies show that IA is among the most commonly missed diagnoses in critically ill patients. And, because of lack of unequivocal diagnostic criteria, a timely diagnosis remains challenging. We investigate the epidemiology of and the clinical risk factors for IA in critically ill patients. We conducted a retrospective, observational study of all consecutive ICU patients with evidence of IA in the postmortem examination. During the period of the study (25 years), 893 postmortem examinations were performed in the ICU. Twenty‐five patients (2.8%) were diagnosed with IA in autopsy. Only ten (40%) were classified as IA ante‐mortem, based on the initiation of antifungal treatment. The most common comorbid conditions were corticosteroid treatment (n = 14, 56%), chronic obstructive pulmonary disease (COPD) (n = 11, 44%), immunosuppression (n = 6, 24%) and haematological malignancy (n = 5, 20%). Twenty‐three patients (92%) had three or more risk factors for IA. Critically ill patients with pulmonary infiltrates, treated with high doses intravenous corticosteroids (even for a short period of time), particularly COPD patients who developed worsening respiratory insufficiency despite appropriate treatment were at the highest risk of IA.  相似文献   

7.
Cryptococcus gattii species complex has evolved as a pathogen in the last two decades causing infection among both immunocompetent and immunocompromised hosts. We aimed to analyse the clinical features of CNS infection caused by C. gattii sensu lato, molecular and antifungal susceptibility profile of this pathogen. Cases diagnosed to have CNS cryptococcosis were included in the study. Cryptococcus recovered from patient's specimen was identified by standard protocol. Species confirmation, mating type and molecular type determination were performed by PCR based methods. Antifungal susceptibility was tested in VITEK2C to amphotericin B, 5‐flucytosine, fluconazole and voriconazole. Among 199 cases, 20 (10%) were due to C. gattii, comprising of 75% cryptococcal meningitis and 25% cryptococcoma cases. Young adult males were commonly affected. Headache and vomiting were prominent symptoms and 50% were immunocompromised. Among the isolates, 75%, 20% and 5% were C. tetragattii, C. gattii sensu stricto and C. bacillisporus respectively and all had mating type α. Four (20%) isolates of C. tetragattii and the only isolate of C. bacillisporus were resistant to fluconazole. The most common species isolated from south India is C. tetragattii. The study contributes to the epidemiology of C. gattii and reiterates the need for genotyping and antifungal susceptibility testing.  相似文献   

8.
Penicilliosis caused by Talaromyces marneffei is a common AIDS‐defining illness in South and Southeast Asia. Diagnosis is based on culture which can take up to 14 days for identification, leading to treatment delay and increased mortality. We developed a TaqMan real‐time PCR assay targeting the MP1 gene encoding an abundant cell wall protein specific to T. marneffei. The assay's performance was evaluated in MP1‐containing plasmids, clinical isolates, and plasma from HIV‐infected patients with and without penicilliosis. The assay consistently detected 10 copies of MP1‐containing plasmids per reaction and 100 T. marneffei yeast cells per millilitre plasma. There were no amplification with seven other Penicillium species and six other HIV‐associated fungal pathogens tested. The assay was evaluated in 70 patients with AIDS: 50 patients with culture‐confirmed penicilliosis and 20 patients with opportunistic infections other than penicilliosis. The diagnostic sensitivity was 70.4% (19/27, 95% CI: 51.5–84.1%) and 52.2% (12/23, 95% CI: 33.0–70.8%) in plasma samples collected prior to and within 48 h of antifungal therapy respectively. The diagnostic specificity was 100% (20/20, 95% CI: 83.9–100%). This assay provides a useful tool for the rapid diagnosis of T. marneffei infection and has the potential to improve the management of patients with penicilliosis.  相似文献   

9.
DNA markers for pancreatic ductal adenocarcinoma (PDAC) are urgently needed for detection of minimally invasive disease. The epigenetic relevance of the cysteine dioxygenase 1 gene (CDO1) has been never investigated in PDAC. Three studies, including cellular experiments, tissue validation, and pilot testing for pancreatic cytology, were carried out. Promoter DNA methylation value (MV) of CDO1 was quantified by quantitative methylation‐specific PCR. CDO1 expression was consistent with its promoter DNA methylation in 7 PDAC cell lines. In 160 retrospectively collected primary PDAC tumor tissues, MV was significantly higher compared to the corresponding noncancerous pancreas (area under the receiver operating characteristic curve [AUC] = 0.97, P < .0001), and CDO1 hypermethylation was highly specific to PDAC tumor tissues. CDO1 hypermethylation group (MV over 19) was significantly associated with diverse prognostic factors in PDAC. Surprisingly, it was significantly higher in prospectively collected PDAC cytology samples (n = 37), including both pancreatic juice (n = 12) and endoscopic ultrasound‐fine needle aspiration (EUS‐FNA) cytology (n = 25) compared to pancreatic benign diseases (AUC = 0.96, P < .0001). Detection of PDAC was confirmed by DNA testing in 35 of 37 patients (95% sensitivity); thus, it was more sensitive than cytology (33%) or EUS‐FNA cytology (88%). Promoter DNA methylation of CDO1 is extremely specific for PDAC tumors, and accumulates with PDAC tumor progression. It could be a definitive diagnostic marker of PDAC in pancreatic juice or EUS‐FNA cytology.  相似文献   

10.
Candidaemia is a potentially fatal infection with varied distribution of Candida species and their antifungal susceptibility profiles. The recent emergence of Candida auris in invasive candidiasis is a cause for concern. This study describes the profile of candidaemia at an Indian tertiary care hospital and reports the emergence of C. auris. All patients diagnosed with candidaemia between 2012 and 2017 were studied. The isolates were identified using conventional methods, VITEK 2 and MALDI‐TOF MS. The isolates not identified by MALDI‐TOF were sequenced. Antifungal susceptibility testing was done by the CLSI broth microdilution method and VITEK 2. A total of 114 isolates of Candida species were analysed. Candida tropicalis (39.4%) was the most common species, followed by C. auris (17.5%), C. albicans (14%) and C. parapsilosis (11.4%). Notably, Diutina mesorugosa isolates (n = 10) were not identified by MALDI‐TOF and were confirmed by sequencing. Furthermore, 45% (n = 9) C. auris strains exhibited low MICs of FLU (0.05‐4 μg/mL) and the remaining 55% (n = 11) isolates had high MICs ≥ 64 μg/mL. Also, D. mesorugosa exhibited high MICs of FLU (32 μg/mL) in 2 isolates. A high rate of errors in antifungal susceptibility was noted with the VITEK 2 as compared to the CLSI method. Candida auris was the second most prevalent species causing candidaemia warranting infection control practices to be strengthened to prevent its spread.  相似文献   

11.
Trichophyton schoenleinii is an anthropophilic dermatophyte usually causing tinea favosa. Only few studies have provided data on molecular epidemiology and antifungal profiles of this fungus due to its limited prevalence after 1950s. Forty‐nine strains from Asia (n = 27), Africa (n = 10), Europe (n = 10) and from unknown regions (n = 2) were analysed with amplified fragment length polymorphism fingerprinting (AFLP) to reveal intraspecific genetic diversity in this dataset. Amplified fragment length polymorphism fingerprinting genotyping revealed five clusters which did not correspond to geographic origins or clinical characteristics. Additionally, in vitro antifungal susceptibility to seven antifungals was provided for all strains. Terbinafine, ketoconazole, miconazole and itraconazole proved to be the most effective drugs, followed by griseofulvin. No correlation between genotypes and differences in antifungal susceptibility was observed. It is concluded that the AFLP groups are lineages within a single species.  相似文献   

12.
Early diagnosis of invasive pulmonary aspergillosis (IPA) remains difficult due to the variable performance of the tests used. We compared the performance characteristics of Aspergillus lateral flow device (LFD) in bronchoalveolar lavage (BAL) vs. BAL‐galactomannan (GM), for the diagnosis of IPA. 311 BAL specimens were prospectively collected from patients who underwent bronchoscopy from January to May 2013. Patients at risk for IPA were divided into haematological malignancy (HEM) and non‐HEM groups: solid organ transplants (SOT) (lung transplant (LT) and non‐LT SOT); chronic steroid use (CSU); solid tumour (STU) and others. We identified 96 patients at risk for IPA; 89 patients (93%) were in the non‐HEM groups: SOT 57 (LT, 46, non‐LT SOT, 11); CSU 21; STU 6, other 5. Only three patients met criteria for IA (two probable; one possible). Overall sensitivity (SS) was 66% for both and specificity (SP) was 94% vs. 52% for LFD and GM respectively. LFD and GM performance was similar in the HEM group (SS 100% for both and SP 83% vs. 100% respectively). LFD performance was better than GM among non‐HEM SOT patients (P = 0.02). Most false‐positive GM results occurred in the SOT group (50.8%), especially among LT patients (56.5%). LFD performance was superior with an overall SP of 95.6% in SOT (P < 0.002) and 97% in LT patients (P = 0.0008). LFD is a rapid and simple test that can be performed on BAL to rule out IPA.  相似文献   

13.
Aspergillus fumigatus is an opportunistic mould that causes invasive pulmonary aspergillosis (IPA), a life‐threatening infection in immunocompromised patients. During the course of IPA, localised areas of tissue hypoxia occur. Bacterial infection models revealed that hypoxic microenvironments modulate the function of host immune cells. However, the influence of hypoxia on anti‐fungal immunity has been largely unknown. We evaluated the impact of hypoxia on the human anti‐A. fumigatus immune response. Human monocyte‐derived dendritic cells (DCs) were stimulated in vitro with germ tubes of A. fumigatus under normoxia or hypoxia (1% O2), followed by analysis of DC viability, maturation and cytokine release. While DC viability was unaffected, hypoxia attenuated cytokine release from DCs and maturation of DCs upon stimulation with A. fumigatus. These data suggest that hypoxia at the site of A. fumigatus infection inhibits full activation and function of human DCs. Thereby, this study identified hypoxia as a crucial immune‐modulating factor in the human anti‐fungal immune response that might influence the course and outcome of IPA in immunocompromised patients.  相似文献   

14.
Aspergillus infections are major causes of morbidity and mortality among immunocompromised patients. This study was designed to investigate the galactomannan assay optical density (OD) indices relative to the culture results in bronchoscopic samples obtained from neutropenic and non‐neutropenic patients. Galactomannan OD indices from 1427 samples from 2005 to 2012, which were sent from 839 patients and were composed of bronchial lavage (BL = 727) and bronchoalveolar lavage fluids (BAL = 700), were retrospectively analysed. The recovery rates of Aspergillus species from these specimens were 9.4% from the combined patient group and 13.3% from the neutropenic group. Aspergillus fumigatus complex was the most frequently isolated species. The mean and median OD indices of the positive and negative culture samples are approximately 5 and 1, respectively, and 91% of all culture‐positive samples have ≥1 OD index value. The receiver‐operating characteristics curve analysis demonstrated that the feasibility of the Aspergillus galactomannan assay and Aspergillus galactomannan test has superior accuracy in BAL compared to BL fluids, and the test is not affected by the immune status of the patient. We suggest that the Aspergillus galactomannan test, which uses bronchoscopic material, leads to an earlier diagnosis and if the OD index is found ≥1, fungal growth can be expected.  相似文献   

15.
Candida auris is an emerging multidrug‐resistant yeast associated with invasive infection in healthcare settings. Recently, C auris cases in the United States have been detected in 11 states with the majority of cases in New York, New Jersey and Illinois. Rapid and accurate identification of C auris is critical for patient care and the implementation of public health measures to control the spread of infection. Our aim was to develop and validate a rapid DNA extraction method using the Roche MagNA Pure 96 instrument and a TaqMan real‐time PCR assay for reliable, high‐throughput identification of C auris. We evaluated 247 patient dermal swab samples previously analysed by culture/MALDI‐TOF. The diagnostic sensitivity and specificity were 93.6% and 97.2%, respectively. The assay was highly reproducible with a detection limit of 1 C auris CFU/10 μL. A receiver operating characteristic curve analysis of the real‐time PCR data showed an area of 0.982 under the curve, with a CT cut‐off value of ≤37.0. The turnaround time from DNA extraction to real‐time PCR results was approximately 200 samples/day. In conclusion, we successfully validated a rapid and high‐throughput method for accurate and reproducible identification of C auris with a significantly reduced turnaround time compared to culture/MALDI‐TOF based methods.  相似文献   

16.
The incidence of invasive aspergillosis (IA) has increased over the last years, especially in immuncompromised patients with high mortality rates. Because of difficulties about the diagnosis; serological methods [galactomannan (GM) antigen test] and polymerase chain reaction (PCR) developed in recent years. MycAssay Aspergillus PCR performance in the diagnosis of IA was evaluated and compared with the GM and in‐house PCR. This study was conducted with 358 serum samples obtained from 99 patient with febrile neutropenic episodes who were followed in haematology and bone marrow transplantation units. Patients were classified by the European Organization for the Research and Treatment of Cancer/Mycoses Study Group criteria, 18 of them is proven and probable IA. GM antigen test and two different real‐time PCR; one of them is fist commercial PCR for IA; Mycassay Aspergillus and the other one is in‐house real‐time PCR performed. Sensitivity values were Mycassay Aspergillus PCR, in‐house PCR, and GM 65.38%, 11.53% and 23.07%, respectively. The high sensitivity obtained from Mycassay Aspergillus PCR and sensitivity is increased by using a combination of diagnostic methods. GM antigen test and real‐time PCR could be beneficial for early diagnosis and treatment of IA. For routine usage of PCR as diagnostic assay more studies needed in future.  相似文献   

17.
Pulmonary mucormycosis (PM) is a life‐threatening infection and the diagnosis can be challenging. The objective was to retrospectively explore the value of the RHS in our cohort of 27 patients with mucormycosis and its relation to neutropenia. This was a retrospective study including all patients with a diagnosis of probable or proven invasive PM according to the 2008 EORTC/MSG criteria between September 2003 to April 2016. Fisher's exact test and Mann‐Whitney test, with a P‐value statistically significant under .05 (P<.05), were used to compare neutropenic and non‐neutropenic groups. 27 patients were eligible. The RHS could be identified in 78% of cases in the neutropenic group, and was less common in the non‐neutropenic group (31%) (P<.05). Reticulations inside ground‐glass opacity in case of RHS were present in 13 out of 15 patients (87%). Mucorales DNA detection by PCR on serum provided, a median time to the first PCR‐positive sample of 3 days (?33 to +60 days) before diagnosis was confirmed. Six patients had IPA co‐infection. In conclusion, RHS is more frequent in case of PM in neutropenic patients compare to non‐neutropenic patients. Its presence in immunocompromised patients should be sufficient to promptly start Mucorales‐active antifungal treatment, while its absence especially in non‐neutropenic cases should not be sufficient to exclude the diagnosis.  相似文献   

18.
Candida auris is a multidrug‐resistant pathogenic yeast whose recent emergence is of increasing public‐health concern. C. auris can colonise multiple body sites, including patients’ skin, and survive for weeks in the health care environment, facilitating patient‐to‐patient transmission and fueling health care‐associated outbreaks. Rapid and accurate detection of C. auris colonisation is essential for timely implementation of infection control measures and to prevent transmission. Currently, axilla/groin composite swabs, used to assess colonisation status, are processed using a culture‐based method that is sensitive and specific but requires 14 days. This delay limits the opportunity to respond and highlights the need for a faster alternative. The culture‐independent T2 Magnetic Resonance (T2MR) system is a rapid diagnostic platform shown to detect target pathogens of interest from unprocessed blood samples in <5 hours. In this study, a new C. auris‐specific T2 assay was evaluated for screening of the skin surveillance samples. Inclusivity and limit of detection of the T2 C.  auris assay were assessed with spiked samples in a representative skin flora background. The T2 C. auris assay recognised isolates from each of the 4 known clades of C. auris and consistently detected cells at 5 CFU/mL. Finally, 89 clinical axilla/groin swab samples were processed with the T2 C. auris assay. The culture‐based diagnostic assay was used as a gold standard to determine performance statistics including sensitivity (0.89) and specificity (0.98). Overall, the T2 C. auris assay performed well as a rapid diagnostic and could help expedite the detection of C. auris in patient skin swabs.  相似文献   

19.
In this study, we aimed to present the first molecular epidemiological data from Chennai, India, analyse keratitis cases that have been monitored in a university hospital during 2 years, identify the responsible Fusarium species and determine antifungal susceptibilities. A total of 10 cases of keratitis were included in the study. Fusarium isolates were identified using the second largest subunit of the RNA polymerase gene (RPB2) and the translation elongation factor 1 alpha (TEF1). Antifungal susceptibility was tested by the broth microdilution method according to the Clinical and Laboratory Standards Institute (CLSI) methodology. The aetiological agents belonged to Fusarium solani species complex (FSSC) (n = 9) and Fusarium sambucinum species complex (FSAMSC) (n = 1), and the identified species were Fusarium keratoplasticum (n = 7), Fusarium falciforme (n = 2) and Fusarium sporotrichioides (n = 1). All strains showed multidrug resistance to azoles and caspofungin but exhibited lower minimum inhibitory concentration (MIC) to natamycin and amphotericin B. Fusarium keratoplasticum and Fusarium falciforme belonging to the Fusarium solani species complex were the major aetiological agents of Fusarium keratitis in this study. Early presentation and 5% topical natamycin was associated with better patient outcome. Preventative measures and monitoring of local epidemiological data play an important role in clinical practice.  相似文献   

20.
Disseminated fusariosis is a life‐threatening, invasive, opportunistic infection in immunocompromised patients, especially those with haematological malignancies. The prognosis is poor because these fungi are resistant to many of the available antifungal agents. We present a case of disseminated fusariosis caused by Fusarium proliferatum in a patient with severe aplastic anaemia complicated by a secondary infection of Aspergillus flavus, with a fatal outcome. We also review the documented Fusarium infections in immunocompromised hosts.  相似文献   

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