Risk of fungal exposure in the homes of patients with hematologic malignancies.

BACKGROUND: Patients with hematological malignancies are at a high risk of developing invasive fungal infections (IFI) because they undergo several cycles of treatment leading to episodes of neutropenia. In addition, they alternate between hospital stays and periods spent at home. Thus, when an IFI is diagnosed during their hospital stays, it is highly challenging to identify the origin of the fungal contamination. The objective of this study was to analyze at home fungal exposure of 20 patients with leukemia by taking air and water samples in their living residence. METHODS: Air was sampled in 3 rooms of each home with a portable air system impactor. Tap water was collected at 3 water distribution points of each home. For positive samples, fungi were identified by mass spectrometry or on the basis of their morphological features. RESULTS: 85 % of homes revealed the presence in air of Aspergillus spp. and those belonging to the section Fumigati presented the highest concentrations and the greatest frequency of isolation. Concerning mucorales, Rhizopus spp. and Mucor spp. were isolated in air of 20 % and 5 % of dwellings, respectively. In 4 homes, more than 70 % of the fungal species identified in air were potential opportunists; these were mainly Aspergillus spp. with concentrations greater than 20 cfu/m3. The water samples revealed the presence of Fusarium in 3 dwellings, with concentrations up to 80 cfu/L. Finally, for one patient, fungal species isolated during a period of hospitalization were phenotypically similar to those isolated in samples taken at home. For a second patient, a PCR Mucorale was positive on a sample of bronchoalveolar fluid while air samples taken at his home also revealed also the presence of mucorales. CONCLUSION: The presence of opportunistic fungal species in the air of all the explored homes suggests the need for strengthened preventive measures in the home of immunocompromised patients. It would be interesting to compare the fungi isolated (from patients and from their environment) by genotyping studies aimed at specifying the correspondence existing between fungal species present in the patients' homes and those responsible for IFI in the same patients.

First Case of Human Primary Vertebral Cystic Echinococcosis Due to Echinococcus Ortleppi.

Cystic echinococcosis (CE) is a cosmopolitan parasitic zoonosis affecting more than one million people worldwide. In humans, primary bone CE is rare and involvement of E. ortleppi is very uncommon. We report here the first case of primary vertebral cystic echinococcosis due to E. ortleppi in Burgundy, France.

Is It Time to Include CT "Reverse Halo Sign" and qPCR Targeting Mucorales in Serum to EORTC-MSG Criteria for the Diagnosis of Pulmonary Mucormycosis in Leukemia Patients?

In 23 leukemia patients with proven (n = 17) or possible (n = 6) pulmonary mucormycosis (PM), the presence of reversed halo sign on computed tomography was strongly associated with the positivity of quantitative polymerase chain reaction assays targeting Mucorales in the serum, confirming the value of these two tools for the diagnosis of PM in this setting.

Candida albicans is able to use M cells as a portal of entry across the intestinal barrier in vitro.

Candida albicans is the most frequent yeast responsible for systemic infections in humans. These infections mainly originate from the gastrointestinal tract where C. albicans can invade the gut epithelial barrier to gain access to the bloodstream. Along the gut, pathogens can use Microfold (M) cells as a portal of entry to cross the epithelial barrier. M cells are specialized cells mainly located in the follicule-associated epithelium of Peyer patches. In this study, we used scanning electron and fluorescence microscopy, adhesion and invasion assays and fungal mutants to investigate the interactions of C. albicans with M cells obtained in an established in vitro model whereby enterocyte-like Caco-2 cells co-cultured with the Raji B cell line undergo a phenotypic switch to morphologically and functionally resembling M cells. Our data demonstrate that C. albicans co-localizes with and invades preferentially M cells, providing evidence that the fungus can use M cells as a portal of entry into the intestinal barrier. In addition to active penetration, F-actin dependent endocytosis contributes to internalization of the fungus into M cells through a mechanism involving hypha-associated invasins including Ssa1 and Als3.

A prospective survey of air and surface fungal contamination in a medical mycology laboratory at a tertiary care university hospital.

BACKGROUND: Invasive filamentous fungi infections resulting from inhalation of mold conidia pose a major threat in immunocompromised patients. The diagnosis is based on direct smears, cultural symptoms, and culturing fungi. Airborne conidia present in the laboratory environment may cause contamination of cultures, resulting in false-positive diagnosis. Baseline values of fungal contamination in a clinical mycology laboratory have not been determined to date. METHODS: A 1-year prospective survey of air and surface contamination was conducted in a clinical mycology laboratory during a period when large construction projects were being conducted in the hospital. Air was sampled with a portable air system impactor, and surfaces were sampled with contact Sabouraud agar plates. The collected data allowed the elaboration of Shewhart graphic charts. RESULTS: Mean fungal loads ranged from 2.27 to 4.36 colony forming units (cfu)/m(3) in air and from 0.61 to 1.69 cfu/plate on surfaces. CONCLUSIONS: Strict control procedures may limit the level of fungal contamination in a clinical mycology laboratory even in the context of large construction projects at the hospital site. Our data and the resulting Shewhart graphic charts provide baseline values to use when monitoring for inappropriate variations of the fungal contamination in a mycology laboratory as part of a quality assurance program. This is critical to the appropriate management of the fungal risk in hematology, cancer and transplantation patients.

A new phenanthrene glycoside and other constituents from Dioscorea opposita.

Phytochemical investigation of the rhizome of Dioscorea opposita has led to the isolation of a new phenanthrene glycoside, 3,4,6-trihydroxyphenanthrene-3-O-beta-D-glucopyranoside (1), and five known compounds, soyacerebroside I (2), adenosine (3), beta-sitosterol (4), palmitic acid (5) and palmitoyloleoylphosphatidylcholine (6). Their structures were determined by spectroscopic methods, including 1D- and 2D-NMR. Compounds 1-6 exhibited no antifungal activity against the human pathogenic yeasts Candida albicans, C. glabrata and C. tropicalis.