Chytridiomycosis, caused by the pathogen Batrachochytrium dendrobatidis (Bd), has led to population declines and extinctions of frog species around the world. While it is known that symbiotic skin ...bacteria can play a protective role against pathogens, it is not known how these defensive bacteria are integrated into the bacterial community on amphibian skin. In this study, we used 16S rRNA gene amplicon sequencing, culturing and Bd inhibition bioassays to characterize the communities of skin bacteria on three Neotropical frog species that persist in a Bd-infected area in Panama and determined the abundance and integration of anti-Bd bacteria into the community. We found that the two treefrog species had a similar bacterial community structure, which differed from the more diverse community found on the terrestrial frog. Co-occurrence networks also revealed differences between frog species such that the treefrogs had a significantly higher number of culturable Bd-inhibitory OTUs with high centrality scores compared with the terrestrial frog. We found that culture-dependent OTUs captured between 21 and 39% of the total relative abundance revealed in culture-independent communities. Our results suggest different ecological strategies occurring within skin antifungal communities on host species that have not succumbed to Bd infections in the wild.
Background and purpose Fungal prosthetic joint infections are rare and difficult to treat. This systematic review was conducted to determine outcome and to give treatment recommendations.
Patients ...and methods After an extensive search of the literature, 164 patients treated for fungal hip or knee prosthetic joint infection (PJI) were reviewed. This included 8 patients from our own institutions.
Results Most patients presented with pain (78%) and swelling (65%). In 68% of the patients, 1 or more risk factors for fungal PJI were found. In 51% of the patients, radiographs showed signs of loosening of the arthroplasty. Candida species were cultured from most patients (88%). In 21% of all patients, fungal culture results were first considered to be contamination. There was co-infection with bacteria in 33% of the patients. For outcome analysis, 119 patients had an adequate follow-up of at least 2 years. Staged revision was the treatment performed most often, with the highest success rate (85%).
Interpretation Fungal PJI resembles chronic bacterial PJI. For diagnosis, multiple samples and prolonged culturing are essential. Fungal species should be considered to be pathogens. Co-infection with bacteria should be treated with additional antibacterial agents.
We found no evidence that 1-stage revision, debridement, antibiotics, irrigation, and retention (DAIR) or antifungal therapy without surgical treatment adequately controls fungal PJI. Thus, staged revision should be the standard treatment for fungal PJI. After resection of the prosthesis, we recommend systemic antifungal treatment for at least 6 weeks-and until there are no clinical signs of infection and blood infection markers have normalized. Then reimplantation can be performed.
Fungal pathogens can affect humans, animals, and plants, and they can be found in the environment or as part of the host microbiome. Fungal diseases present a broad clinical spectrum, ranging from ...superficial to invasive infections, and can cause outbreaks. During an outbreak investigation, the laboratory plays an essential role in verifying the diagnosis and helping to confirm the source of the outbreak. Immunodiagnostic assays are important tools and often relied upon for the diagnosis of fungal infections, since the gold standard assays of culture and histopathology are time-consuming and often require invasive procedures. Immunodiagnostic assays range from complement fixation and immunodiffusion to enzyme immunoassays and, most recently, to point-of-care lateral flow devices. In general, these assays provide results faster and offer good analytical performance. These characteristics make immunodiagnostic assays good laboratory tools for outbreak investigations. The aim of this review is to describe the principles, advantages, limitations, and availability of immunodiagnostics assays in outbreak investigations, based on the experience of a reference laboratory.
Isolation and characterization of the new species Chrysosporium ophiodiicola from a mycotic granuloma of a black rat snake (Elaphe obsoleta obsoleta) are reported. Analysis of the sequences of ...different fragments of the ribosomal genes demonstrated that this species belongs to the Onygenales and that this species is genetically different from other morphologically similar species of CHRYSOSPORIUM: This new species is unique in having both narrow and cylindrical-to-slightly clavate conidia and a strong, pungent odor.
Batrachochytrium dendrobatidis , a pathogenic chytrid fungus implicated in worldwide amphibian declines, is considered an amphibian specialist. Identification of nonamphibian hosts could help explain ...the virulence, heterogeneous distribution, variable rates of spread, and persistence of B. dendrobatidis in freshwater ecosystems even after amphibian extirpations. Here, we test whether mosquitofish (Gambusia holbrooki) and crayfish (Procambarus spp. and Orconectes virilis), which are syntopic with many amphibian species, are possible hosts for B. dendrobatidis . Field surveys in Louisiana and Colorado revealed that zoosporangia occur within crayfish gastrointestinal tracts, that B. dendrobatidis prevalence in crayfish was up to 29%, and that crayfish presence in Colorado wetlands was a positive predictor of B. dendrobatidis infections in cooccurring amphibians. In experiments, crayfish, but not mosquitofish, became infected with B. dendrobatidis , maintained the infection for at least 12 wk, and transmitted B. dendrobatidis to amphibians. Exposure to water that previously held B. dendrobatidis also caused significant crayfish mortality and gill recession. These results indicate that there are nonamphibian hosts for B. dendrobatidis and suggest that B. dendrobatidis releases a chemical that can cause host pathology, even in the absence of infection. Managing these biological reservoirs for B. dendrobatidis and identifying this chemical might provide new hope for imperiled amphibians.
The composition and antifungal activity of clove essential oil (EO), obtained from Syzygium aromaticum, were studied. Clove oil was obtained commercially and analysed by GC and GC-MS. The EO analysed ...showed a high content of eugenol (85.3 %). MICs, determined according to Clinical and Laboratory Standards Institute protocols, and minimum fungicidal concentration were used to evaluate the antifungal activity of the clove oil and its main component, eugenol, against Candida, Aspergillus and dermatophyte clinical and American Type Culture Collection strains. The EO and eugenol showed inhibitory activity against all the tested strains. To clarify its mechanism of action on yeasts and filamentous fungi, flow cytometric and inhibition of ergosterol synthesis studies were performed. Propidium iodide rapidly penetrated the majority of the yeast cells when the cells were treated with concentrations just over the MICs, meaning that the fungicidal effect resulted from an extensive lesion of the cell membrane. Clove oil and eugenol also caused a considerable reduction in the quantity of ergosterol, a specific fungal cell membrane component. Germ tube formation by Candida albicans was completely or almost completely inhibited by oil and eugenol concentrations below the MIC values. The present study indicates that clove oil and eugenol have considerable antifungal activity against clinically relevant fungi, including fluconazole-resistant strains, deserving further investigation for clinical application in the treatment of fungal infections.
Fungal infections remain a significant global health problem in humans. Fungi infect millions of people worldwide and cause from acute superficial infections to life-threatening systemic disease to ...chronic illnesses. Trying to decipher the complex innate and adaptive immune mechanisms that protect humans from pathogenic fungi is therefore a key research goal that may lead to immune-based therapeutic strategies and improved patient outcomes. In this review, we summarize how the cells and molecules of the innate immune system activate the adaptive immune system to elicit long-term immunity to fungi. We present current knowledge and exciting new advances in the context of organ-specific immunity, outlining the tissue-specific tropisms for the major pathogenic fungi of humans, the antifungal functions of tissue-resident myeloid cells, and the adaptive immune responses required to protect specific organs from fungal challenge.
Background.Prompt diagnosis of invasive pulmonary aspergillosis (IPA) remains a challenge. Galactomannan (GM) detection in bronchoalveolar lavage (BAL) fluid by the Platelia enzyme immunoassay aims ...to further improve upon the test's utility by applying it directly to specimens from the target organ. Methods.A retrospective analysis of the Platelia assay was performed on BAL samples from 99 evaluable high-risk hematology patients, including 58 with proven or probable IPA. Results.BAL GM demonstrated an improved sensitivity profile (91.3% with an optical density OD index cutoff of ⩾1.0) in comparison with culture and microscopy (50% and 53.3%, respectively). The diagnostic accuracy as given by the area under the receiver operating characteristic curve was 0.93 (95% confidence interval, 0.88–0.99); further decreasing the OD index cutoff to ⩾0.5 compromised specificity more than it improved sensitivity. Estimates of the positive and negative predictive value of the Platelia assay on BAL samples (OD index, ⩾1.0) were 76% and 96%, respectively. The mean BAL GM OD index was not different in neutropenic versus nonneutropenic case patients (3.9 and 4.5, respectively; P=.3); however, a trend toward decreased sensitivity in patients receiving mold-active prophylaxis was noted. Conclusion.BAL GM is a valuable adjunctive diagnostic tool to other conventional microbiologic and radiologic studies.
Treatment of cirrhotic patients with spontaneous peritonitis using antibiotics occasionally fails. Fungal infections may be one of the causes of antibiotic treatment failure in such patients. In this ...study we evaluated the clinical significance and characteristics of spontaneous fungal peritonitis (SFP). Consecutive cirrhotic patients with spontaneous peritonitis treated between 2000 and 2005 at a tertiary care center in Seoul, Korea, were included. We analyzed the clinical characteristics and the prognosis of SFP patients compared with patients with spontaneous bacterial peritonitis (SBP). During the study period 416 patients developed spontaneous peritonitis and 15 (3.6 %) had SFP. Compared with patients with SBP, nosocomial peritonitis (peritonitis that developed after hospitalization for >72 h) was more common and the Child–Pugh score was higher in SFP patients (both,
P
< 0.01). Ten patients were infected with
Candida
spp. (
C. albicans
, 8;
C. tropicalis
, 1;
C. glabrata
, 1), and 5 with
Cryptococcus neoformans
. Eleven patients were co-infected with bacteria that were susceptible to the antibiotics administered. Only 5 patients were treated using appropriate anti-fungal agents. The 1-month mortality rate for SFP patients was 73.3 % (11 out of 15; median time to death, 2 days range, 0–22), which was significantly higher than patients with SBP alone (28.7 %,
P
= 0.0007). SFP is severe complication related to high mortality in cirrhotic patients. A longer admission and a higher Child–Pugh score may be risk factors. Immediate anti-fungal treatment is warranted in patients with spontaneous peritonitis, once fungus is found in the ascitic fluid.
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