Relationship between Fungal Colonisation of the Respiratory Tract in Lung Transplant Recipients and Fungal Contamination of the Hospital Environment.

Background: Aspergillus colonisation is frequently reported after lung transplantation. The question of whether aspergillus colonisation is related to the hospital environment is crucial to prevention.

Method: To elucidate this question, a prospective study of aspergillus colonisation after lung transplantation, along with a mycological survey of the patient environment, was performed.

Use and limits of (1-3)-β-d-glucan assay (Fungitell), compared to galactomannan determination (Platelia Aspergillus), for diagnosis of invasive aspergillosis.

This study was undertaken to examine the performance of the Fungitell β-glucan (BG) assay, to compare it with that of the galactomannan (GM) test for the diagnosis of invasive aspergillosis (IA) in patients with hematological malignancies, and to examine the rates of false-positive BG and GM test results due to β-lactam antibiotics among sera of patients with Gram-positive or Gram-negative bacteremia and selected sera with false-positive results from the GM test. Serum samples from 105 patients with proven (n = 14) or probable (n = 91) IA, 97 hematology patients at risk for invasive fungal infections, 50 healthy blood donors, and 60 patients with bacteremia were used to study the sensitivities and specificities of the assays. The GM test was more specific than the BG assay (97% versus 82%, respectively; P = 0.

Performance of the BioPlex 2200 flow immunoassay in critical cases of serodiagnosis of toxoplasmosis.

The BioPlex 2200 automated analyzer (Bio-Rad Laboratories, Hercules, CA) is a recently developed multiplex analyzer that enables the detection of anti-Toxoplasma, -rubella, and -cytomegalovirus antibodies in the same assay. The aim of this study was to compare this new technology (using the BioPlex 2200 ToRC IgG/IgM kit) in critical cases of serodiagnosis of toxoplasmosis (acute, chronic, or congenital infections and cases with discrepant results) to the technologies used in our routine practice, i.e.

Evidence of airborne excretion of Pneumocystis carinii during infection in immunocompetent rats. Lung involvement and antibody response.

To better understand the role of immunocompetent hosts in the diffusion of Pneumocystis in the environment, airborne shedding of Pneumocystis carinii in the surrounding air of experimentally infected Sprague Dawley rats was quantified by means of a real-time PCR assay, in parallel with the kinetics of P. carinii loads in lungs and specific serum antibody titres. Pneumocystis-free Sprague Dawley rats were intratracheally inoculated at day 0 (d0) and then followed for 60 days.

Bayesian development of a dose-response model for Aspergillus fumigatus and invasive aspergillosis.

Invasive aspergillosis (IA) is a major cause of mortality in immunocompromized hosts, most often consecutive to the inhalation of spores of Aspergillus. However, the relationship between Aspergillus concentration in the air and probability of IA is not quantitatively known. In this study, this relationship was examined in a murine model of IA.

Efficacy of liposomal amphotericin B for prophylaxis of acute or reactivation models of invasive pulmonary aspergillosis.

The efficacy of antifungal prophylaxis for prevention of invasive aspergillosis (IA) may depend on whether IA results from recent inhalation of spores or reactivation of latent colonisation. Compare the efficacy of liposomal amphotericin B (LAmB) for prophylaxis in acute and reactivation models of IA. In the acute model, mice immunosuppressed from day 0 were challenged at day 3 with an aerosol of Aspergillus fumigatus.

Prevalence of opportunistic intestinal parasitic infections among HIV-infected patients with low CD4 cells counts in France in the combination antiretroviral therapy era.

Background: The use of combination antiretroviral therapy (cART) has dramatically reduced the prevalence of opportunistic infections, however data on the prevalence of intestinal parasitic infections in HIV-infected patients with low CD4 cell counts in the cART era are scarce.

Methods: We performed a prospective cohort study among HIV-infected patients with CD4 cell counts <100/mm(3) seen at a university hospital in Paris. Medical records were reviewed and stool samples were obtained for macroscopic examination and detection of parasites including cryptosporidia and microsporidia, whether or not the patient had diarrhea.

Prospective evaluation of clinical and biological markers to predict the outcome of invasive pulmonary aspergillosis in hematological patients.

Early evaluation of treatment efficacy in invasive aspergillosis (IA), a leading cause of morbidity and mortality in hematological patients, remains a challenge. We conducted a prospective study to evaluate the performance of different markers in predicting the outcome of patients with IA. Both clinical and biological criteria were assessed 7, 14, 21, and 45 days after inclusion in the study, and mortality was assessed at day 60.

The strategy for the diagnosis of invasive pulmonary aspergillosis should depend on both the underlying condition and the leukocyte count of patients with hematologic malignancies.

The identification of the causative organism in invasive pulmonary aspergillosis (IPA) is recommended. We investigated whether a mycologic diagnostic strategy could be optimized based on patient characteristics. Fifty-five patients were enrolled in a prospective study.

Sequential air-liquid exposure of human respiratory cells to chemical and biological pollutants.

Although indoor air has wide ranging effects on human health, the effects of environmental, chemical, and biological pollutants on the respiratory system are not fully understood. In order to clarify the health effects of airborne pollutant exposure, it would appear that toxicological evidence is needed to complement epidemiological observations to support by providing biological plausibility. The aim of this study is to manage air-liquid successive exposures to different pollutants such as a chemical pollutant (formaldehyde--FA), and a biological contaminant (Aspergillus fumigatus--Asp) using our in vitro model.

Dynamics of Pneumocystis carinii air shedding during experimental pneumocystosis.

To better understand the diffusion of Pneumocystis in the environment, airborne shedding of Pneumocystis carinii in the surrounding air of experimentally infected rats was quantified by means of a real-time polymerase chain reaction assay, in parallel with the kinetics of P. carinii loads in their lungs. P.

Accumulation and transport of microbial-size particles in a pressure protected model burn unit: CFD simulations and experimental evidence.

Background: Controlling airborne contamination is of major importance in burn units because of the high susceptibility of burned patients to infections and the unique environmental conditions that can accentuate the infection risk. In particular the required elevated temperatures in the patient room can create thermal convection flows which can transport airborne contaminates throughout the unit. In order to estimate this risk and optimize the design of an intensive care room intended to host severely burned patients, we have relied on a computational fluid dynamic methodology (CFD).

Quantification and spread of Pneumocystis jirovecii in the surrounding air of patients with Pneumocystis pneumonia.

Background: Airborne transmission of Pneumocystis has been demonstrated in animal models and is highly probable in humans. However, information concerning burdens of Pneumocystis jirovecii (human-derived Pneumocystis) in exhaled air from infected patients is lacking. Our objective is to evaluate P.

Disseminated infection with a new genovar of Encephalitozoon cuniculi in a renal transplant recipient.

Disseminated microsporidiosis is a life-threatening opportunistic infection. Here, we report about a previously undescribed genovar of Encephalitozoon cuniculi causing disseminated infection in a non-HIV-infected renal transplant recipient. Disseminated microsporidiosis must be considered in the differential diagnosis of chronic fever in renal allograft recipients, even those without urinary symptoms.

Identification of cryptosporidium species infecting humans in Tunisia.

Prevalence and species distribution of Cryptosporidium spp. were determined among 633 immunocompetent children less than five years of age and 75 patients hospitalized for immunodeficiency who lived in northern Tunisia. Microscopy was used for initial screening to detect positive samples and a nested polymerase chain reaction and restriction fragment length polymorphism analysis was used to determine the species.

Restoration of Toxoplasma gondii-specific immune responses in patients with AIDS starting HAART.

Objective: To study the kinetics and identify factors associated with Toxoplasma-specific immune responses in patients with AIDS starting antiretroviral therapy.

Methods: A prospective study of 38 HIV-infected patients seropositive for Toxoplasma who started antiretroviral therapy with CD4 T cells less than 200 cells/microl. T-cell and B-cell phenotypes, anti-Toxoplasma antibodies titers, Th-1 and Th-2 cytokine production and lymphocyte proliferative responses (LPRs) to Toxoplasma were assessed over 12 months.

Treatment of parasitic diarrhea in HIV-infected patients.

Parasitic infections responsible for diarrhea have a worldwide distribution, overlapping with AIDS in most countries. Indeed, highly active antiretroviral therapy has markedly reduced the incidence of most parasitic opportunistic infections, but parasite-related diarrhea remains frequent and probably underestimated in developing countries. In this review, we focus on the advances in molecular epidemiology, diagnosis and current treatment of the most prevalent parasitic infections in HIV-infected patients.

Effects of ozone and ultraviolet radiation treatments on the infectivity of Toxoplasma gondii oocysts.

Clinical toxoplasmosis in humans has been epidemiologically linked to the consumption of drinking water contaminated by Toxoplasma gondii oocysts. We evaluated killing of T. gondii oocysts after ultraviolet (UV) or ozone treatments by bioassay in mice and/or cell culture.

In vitro susceptibility of various genotypic strains of Toxoplasma gondii to pyrimethamine, sulfadiazine, and atovaquone.

Sulfadiazine, pyrimethamine, and atovaquone are widely used for the treatment of severe toxoplasmosis. Their in vitro activities have been almost exclusively demonstrated on laboratory strains belonging to genotype I. We determined the in vitro activities of these drugs against 17 strains of Toxoplasma gondii belonging to various genotypes and examined the correlations among 50% inhibitory concentrations (IC50s), growth kinetics, strain genotypes, and mutations on drug target genes.

New active drugs against liver stages of Plasmodium predicted by molecular topology.

We conducted a quantitative structure-activity relationship (QSAR) study based on a database of 127 compounds previously tested against the liver stage of Plasmodium yoelii in order to develop a model capable of predicting the in vitro antimalarial activities of new compounds. Topological indices were used as structural descriptors, and their relation to antimalarial activity was determined by using linear discriminant analysis. A topological model consisting of two discriminant functions was created.

Contribution of the (1-->3)-beta-D-glucan assay for diagnosis of invasive fungal infections.

Diagnosis of invasive fungal infection (IFI) remains a challenge. A retrospective study was performed on 279 patients at three French university hospitals to evaluate the performance of the (1-->3)-beta-D-glucan assay (BG assay; Fungitell; Associates of Cape Cod, Inc.) for the diagnosis of IFI.

Pilot-scale evaluation of UV reactors' efficacy against in vitro infectivity of Cryptosporidium parvum oocysts.

An experimental protocol was developed to assess the efficacy of two UV reactors (medium-pressure UVaster), and a low-pressure reactor) on the infectivity of Cryptosporidium parvum oocysts under conditions mimicking small- or medium-size water distribution units. The protocol included purification of large amounts of viable oocysts from experimentally infected calf feces, pilot spiking, sample concentration and purification after UV radiation, oocyst quantification and in vitro evaluation of oocyst infectivity on HCT-8 cells. Water samples were collected at intervals upstream and downstream from the UV reactor after spiking.