59 research outputs found
Multilocus sequence typing of Scedosporium apiospermum and Pseudallescheria boydii isolates from cystic fibrosis patients
Background: Scedosporium and Pseudallescheria species are the second most common lung-colonising fungi in cystic fibrosis (CF) patients. For epidemiological reasons it is important to trace sources of infection, routes of transmission and to determine whether these fungi are transient or permanent colonisers of the respiratory tract. Molecular typing methods like multilocus sequence typing (MLST) help provide this data. Methods: Clinical isolates of the P. boydii complex (including S. apiospermum and P. boydii) from CF patients in different regions of Germany were studied using MLST. Five gene loci, ACT, CAL, RPB2, BT2 and SOD2, were analysed. Results: The S. apiospermum isolates from 34 patients were assigned to 32 sequence types (STs), and the P. boydii isolates from 14 patients to 8 STs. The results revealed that patients can be colonised by individual strains for years. Conclusions: The MLST scheme developed for S. apiospermum and P. boydii is a highly effective tool for epidemiologic studies worldwide. The MLST data are accessible at http://mlst.mycologylab.org/
Multiphasic and multifocal cryptococcal immune reconstitution inflammatory syndrome in an HIV-infected patient: interplay of infection and immunity
SummaryWe report a case of cryptococcal immune reconstitution inflammatory syndrome affecting the lungs, and 10 months later the cervical lymph nodes, in the absence of cryptococcal meningitis, in advanced HIV infection. Our report demonstrates the organ-specificity of the timing of the inflammatory response and illustrates the organ-specific interplay of immunity and infection in cryptococcal disease
Multilocus Sequence Typing Reveals Extensive Genetic Diversity of the Emerging Fungal Pathogen Scedosporium aurantiacum
Scedosporium spp. are the second most prevalent filamentous fungi after Aspergillus spp. recovered from cystic fibrosis (CF) patients in various regions of the world. Although invasive infection is uncommon prior to lung transplantation, fungal colonization may be a risk factor for invasive disease with attendant high mortality post-transplantation. Abundant in the environment, Scedosporium aurantiacum has emerged as an important fungal pathogen in a range of clinical settings. To investigate the population genetic structure of S. aurantiacum, a MultiLocus Sequence Typing (MLST) scheme was developed, screening 24 genetic loci for polymorphisms on a tester strain set. The six most polymorphic loci were selected to form the S. aurantiacum MLST scheme: actin (ACT), calmodulin (CAL), elongation factor-1α (EF1α), RNA polymerase subunit II (RPB2), manganese superoxide dismutase (SOD2), and ÎČ-tubulin (TUB). Among 188 global clinical, veterinary, and environmental strains, 5 to 18 variable sites per locus were revealed, resulting in 8 to 23 alleles per locus. MLST analysis observed a markedly high genetic diversity, reflected by 159 unique sequence types. Network analysis revealed a separation between Australian and non-Australian strains. Phylogenetic analysis showed two major clusters, indicating correlation with geographic origin. Linkage disequilibrium analysis revealed evidence of recombination. There was no clustering according to the source of the strains: clinical, veterinary, or environmental. The high diversity, especially amongst the Australian strains, suggests that S. aurantiacum may have originated within the Australian continent and was subsequently dispersed to other regions, as shown by the close phylogenetic relationships between some of the Australian sequence types and those found in other parts of the world. The MLST data are accessible at http://mlst.mycologylab.org. This is a joined publication of the ISHAM/ECMM working groups on âScedosporium/Pseudallescheria Infectionsâ and âFungal Respiratory Infections in Cystic Fibrosisâ.Peer Reviewe
Breakthrough zygomycosis on posaconazole prophylaxis after allogeneic stem cell transplantation.
Antifungal prophylaxis with posaconazole (POS) has been shown to decrease the mortality associated with invasive fungal infections in high-risk patients. We report on a patient, with severe graft-versus-host disease after allogeneic stem cell transplantation, who developed proven pneumonia due to Rhizopus microsporus after 40 days of POS prophylaxis (fasting serum levels: 691â904 ng/mL). Despite combination treatment with liposomal amphotericin B and POS for 39 days, the patient died from pulmonary hemorrhage. This case highlights the need for continued awareness of breakthrough zygomycosis in patients receiving POS
Kryptokokkose: Kasuistiken, Epidemiologie und Therapiestrategien
Die Kryptokokkose ist eine Pilzinfektion, die meist durch Cryptococcus neoformans verursacht wird. Neben den seltener werdenden Erkrankungen bei HIV-Infizierten werden zunehmend FĂ€lle bei anderen Patientenkollektiven wie Organtransplantierten, Patienten mit chronischen Organerkrankungen oder auch bei Patienten ohne Immundefekt diagnostiziert. Das Krankheitsbild reicht von lokalisierten Infektionen der Atemwege oder der Haut bis hin zur typischen Meningoenzephalitis nach hĂ€matogener Dissemination. Da aber auch alle anderen Organe beteiligt sein können, resultiert eine vielgestaltige PrĂ€sentation der Erkrankung. Daher muss die Kryptokokkose oft in die differenzialdiagnostischen Ăberlegungen einbezogen werden. Aufgrund sensitiver Labortests kann die Erkrankung bei disseminierter Infektion rasch gesichert werden. FĂŒr therapeutische Entscheidungen sind Patientenfaktoren und die jeweilige Organbeteiligung ausschlaggebend. WĂ€hrend in der ersten Therapiephase bei disseminierten oder schweren lokalen Erkrankungen in der Regel Amphotericin B-Derivate und 5-Flucytosin in Kombination eingesetzt werden, ist nach dieser Induktionstherapie oder bei leichten lokalisierten Infektionen eine Therapie mit Fluconazol indiziert. Echinocandine sind bei der Kryptokokkose nicht wirksam.Cryptococcosis is a fungal infection that is usually caused by Cryptococcus neoformans. Given the decreasing number of cases in HIV-infected patients in developed countries, infections in other patient populations, such as solid organ transplant recipients, patients with chronic organ diseases or even patients without immunodeficiency gain more attention. Due to a possible involvement of many organs, the clinical presentation varies from localized infections of the respiratory tract and the skin, to the characteristic meningoencephalitis or other organs after hematogenous dissemination. Sensitive laboratory tests allow a rapid diagnosis in patients with disseminated infection. Crucial therapeutic decisions depend on the underlying patient condition and the particular organ involvement. The induction therapy of disseminated infections or severe localised infections is based on amphotericin B in combination with 5-flucytosine. In non-severe localised infections and after induction therapy, antifungal treatment with fluconazole is indicated. Echinocandins are not effective in cryptococcosis
Infections due to Pseudallescheria/Scedosporium species in patients with advanced HIV disease â a diagnostic and therapeutic challenge
Objectives: The aim of this study is to highlight the importance of infections caused by members of the genera Pseudallescheria/Scedosporium in HIV-positive patients. Methods: We describe a case of a fatal scedosporiosis in a treatment-naĂŻve HIV patient and review all previously reported cases of pseudallescheriosis/scedosporiosis from a search of the PubMed and Deutsches Institut fĂŒr Medizinische Dokumentation und Information (DIMDI) databases, applying the terms âPseudallescheriaâ, âScedosporiumâ, âAllescheriaâ, âMonosporiumâ, âPetriellidiumâ, âboydiiâ, âprolificansâ, âinflatumâ, cross-referenced with âHIVâ and âAIDSâ. Results: Detection of Scedosporium and Pseudallescheria species has been reported in 22 HIV-positive patients. Fourteen isolates belonged to the Pseudallescheria boydii complex and eight to Scedosporium prolificans. Invasive scedosporiosis (IS) was proven in 54.5% of the patients. Among them dissemination was observed in 66.7%. Pseudallescheria/Scedosporium species were mainly isolated from male individuals. Patients with proven IS showed CD4+ cell count
Fast broad-range disinfection of bacteria, fungi, viruses and prions
Effective disinfectants are of key importance for the safe handling and reprocessing of surgical instruments. We tested whether new formulations containing SDS, NaOH and 1-propanol (n-propanol) are simultaneously active against a broad range of pathogens including bacteria, fungi, non-enveloped viruses and prions. Inactivation and disinfection were examined in suspension and on carriers, respectively, using coagulated blood or brain homogenate as organic soil. Coomassie blue staining was used to assess whether formulations did undesirably fix proteins to rough surfaces. A mixture of 0.2% SDS and 0.3% NaOH in 20% n-propanol achieved potent decontamination of steel carriers contaminated with PrPTSE, the biochemical marker for prion infectivity, from 263K scrapie hamsters, or patients with sporadic or variant Creutzfeldt-Jakob disease. 263K scrapie infectivity on carriers was decreased by â„5.5 log10 units [logs]. Furthermore, the formulation effectively inactivated poliovirus, hepatitis A virus and caliciviruses (including murine norovirus) in suspension tests. It also yielded significant titre reductions of bacteria (E. faecium, M. avium; >6 logs), fungi (spores of Aspergillus niger; >5 logs) or poliovirus (â„4 logs) embedded in coagulated blood on carriers. The formulation was not found to fix proteins more than was observed with water as cleaning reagent. SDS, NaOH and n-propanol can synergistically achieve fast broad-range disinfection
Pitfalls in Serological Diagnosis of Cryptococcus gattii Infections
The detection of cryptococcal antigen by latex agglutination tests (LATs), enzyme-linked immunoassays (ELISA), or lateral flow assay (LFA) is an important tool for diagnosis of a Cryptococcus infection. Cerebrospinal fluid and/or serum samples of 10 patients with cryptococcosis due to Cryptococcus gattii or a hybrid of Cryptococcus neoformans and C. gattii were examined by three LATs (the IMMY Latex-Crypto(Âź) test, the Pastorex(TM) Crypto Plus, and the Remel Cryptococcus Antigen Test Kit) and the LFA made by Immuno-Mycologics. LATs based on monoclonal antibodies (mAbs) like the Pastorex(TM) Crypto Plus or the Remel Cryptococcus Antigen Test Kit turned out to have an insufficient sensitivity to detect four out of 10 C. gattii infections, including one infection by a hybrid between C. gattii and C. neoformans. Reflecting the ongoing expansion of C. gattii in geographical zones outside of tropical and subtropical areas like Mediterranean countries, Vancouver Island (British Columbia, Canada) and the Pacific Northwest region (USA), these findings are alarming because of the risk of delayed diagnosis of infections caused by C. gattii. Therefore, the preliminary serological screening for cryptococcal antigen in the case of a suspected Cryptococcus infection should be performed by using an assay with a broad range specificity and sensitivity for C. neoformans and C. gattii, including their hybrids
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