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R Grillot

Publications and source records attributed to R Grillot.

At least 37 records · Page 2Linked to original sources

[Epidemiology of fungemia in a university hospital; therapeutic incidence].

Twenty-two candidemia happened in our hospital from January 1997 to may 1998. We studied the clinical evolution of the patients and the sensitivity of the yeasts to antifungal therapy (Fungitest and E-Test method). We found 11 Candida albicans (CA), 10 Candida non albicans (CNA) (3 C. glabrata, 2 C. parapsilosis, 4 C. tropicalis, 1 C. krusei) and 1 Saccharomyces cerevisiae. The mean age of the patients was 56.4 years. There were 13 men and 9 women. We found one group of 8 (36.4%) oncohematological patients, one group of 8 (36.4%) patients with abdominal surgery, one group of 3 (13.6%) children and one group of 3 adults (13.6%) who spent more than 10 days in an intensive care unit. Ten times, these candidemia were associated with bacteriemia, 4 times with several bacteria. Three patients died because of the candidemia, 2 times with CNA and one time with CA. There wasn't any resistance to amphotericin B or ketoconazole. All the CA and 3 CNA (30%) remained sensitive to the four antifungal drugs we used (amphotericin B, ketoconazole, fluconazole, itraconazole). The 3 C. glabrata and the C. krusei were resistant or limit to fluconazole. Since the generalization of the use of fluconazole, the epidemiology is marked by the emergence of new strains of CA with high level of resistance to azols, and of CNA. In our hospital, the CA remain preponderant and only the CNA are resistant to fluconazole making difficult the choice of empiric treatment for serious fungemia.

Adult↗

Use of simulated blood cultures to compare a specific fungal medium with a standard microorganism medium for yeast detection.

The aim of this study was to compare the performance of a specific blood culture medium recently developed to detect fungi on the Bactec 9240 system (Mycosis IC/F; Becton Dickinson Diagnostic Instrument Systems, USA) with that of the standard medium used for detection of bacteria (Aerobic Plus/F; Becton Dickinson). Simulated blood cultures were performed on 43 strains belonging to ten fungal species using the two media. The mean time to yeast detection using the Mycosis IC/F medium was 29.03+/-13.99 h, in contrast to a mean time of 73.92+/-56.74 h using the Aerobic Plus/F medium. These results show that the Mycosis IC/F medium clearly reduces the time to yeast detection on the Bactec 9240.

Automation↗

A monoclonal antibody specific to surface antigen on Candida krusei.

A monoclonal antibody (MAb; MAb 6B3) which reacts specifically with a cell wall antigen found in all strains or isolates of Candida krusei was developed. MAb 6B3 was extensively tested by immunofluorescence assay for cross-reaction with many Candida, Cryptococcus, Saccharomyces, Trichosporon, and Rhodotorula species and was found to react only with the species C. krusei. The specific epitope is expressed on the surface of fungal cells and appears to reside on a protein moiety. Taking into account the increasing importance of fluconazole-resistant strains in nosocomial fungal infections, the very high degree of specificity of this MAb for C. krusei could be useful for the routine detection of C. krusei in culture or in tissue samples.

Animals↗

[Fungal and parasitic nosocomial infections: importance and limitations of disinfection methods].

Due to the increase of opportunistic mycosis and parasitosis for several years, the management of fungal and parasitic risk in hospital has become a necessity and an obligation. The authors remind the main rules and knowledges essential to an optimal management of the fungal and parasitic disinfection in hospital. They summarize the efficiency of different disinfection processes in relation to yeasts, filamentous fungi, Pneumocystis carinii, Cryptosporidia and Microsporidia involved in hospital pathology.

Animals↗

Does hydrocortisone modify the in vitro susceptibility of Aspergillus fumigatus to itraconazole and amphotericin B?

To analyse if hydrocortisone could modify the in vitro susceptibility of Aspergillus fumigatus to antifungal drugs, we developed a procedure to test the susceptibility of an A. fumigatus strain to amphotericin B and itraconazole, grown in the presence and in the absence of hydrocortisone. Conidia were germinated in the presence or the absence of hydrocortisone in Czapek medium without antifungal drug. A dilution of these cultures (5x10(3) conidia ml(-1)) was spread onto Czapek-agarose plates containing both antifungal drug and hydrocortisone. The cfu per plate were enumerated and compared. A therapeutic concentration of hydrocortisone induced a significant increase in the susceptibility to itraconazole. Conversely, the susceptibility to amphotericin B was not significantly modified when this antifungal drug was associated with hydrocortisone.

Amphotericin B↗

Aspergillus and lung transplant recipients: a mycologic and molecular epidemiologic study.

BACKGROUND: After lung transplantation, filamentous fungi and more particularly Aspergillus fumigatus are commonly isolated, although the origin of contamination is unclear. METHODS: To investigate the fungal flora in bronchoscopic fluids, we retrospectively reviewed 20 cases of lung transplant recipients. Using sequence-specific DNA primers analysis, we typed the clinical strains of A. fumigatus isolated from 6 lung transplant recipients. For 4 of them, the strains of this species were isolated from their environment. RESULTS: At least once 90% of patients had filamentous fungi, and A. fumigatus was the most frequently isolated. Bronchial colonization was detected in 14 patients, invasive bronchial mycosis was diagnosed in 4 others, and no case of invasive pulmonary fungal infection was detected. Genome typing of the 47 clinical strains revealed that a given patient could be affected by several different strains. A very extensive polymorphism existed among the 38 environmental strains. Origin of contamination at home was possible in 1 case and in the hospital in 3 cases. CONCLUSIONS: Bronchial colonization is frequent after lung transplantation. Although the clinical strains show a polymorphism, it is less widespread than the polymorphism of environmental strains. The origin of acquisition may be in the patient's community.

Adult↗

Molecular typing of Aspergillus fumigatus strains by sequence-specific DNA primer (SSDP) analysis.

A PCR typing method has been developed and tested to investigate the polymorphism of clinical strains of Aspergillus fumigatus. Firstly, the DNA fragments from random amplified polymorphic DNA (RAPD) patterns of nine epidemiologically and geographically non-related monosporal strains of A. fumigatus were cloned and sequenced. The pairs of five sequence-specific DNA primers (SSDP), characteristic of the 5' and 3' extremities of the RAPD products, were then used in high stringency PCR to type 43 clinical strains of A. fumigatus from 13 patients, according to the presence or absence of a single amplified band. This original approach, which uses the advantages of PCR, has made it possible to overcome the difficulties resulting from the low stringency amplification. The SSDP analysis of 51 A. fumigatus strains (9 unrelated monosporal strains and 43 clinical strains from 13 patients) can be classed into 22 different types with a high reproducibility and a high level of discrimination (D = 0.96). The results suggest that seven lung transplant patients with necrotizing aspergillosis, bronchitis aspergillosis and bronchial colonization were infected by multiple strain genotypes, whereas three patients with invasive aspergillosis seem to have been infected by a single strain.

Aspergillosis↗

Variation in virulence of Aspergillus fumigatus strains in a murine model of invasive pulmonary aspergillosis.

The diversity in virulence of different Aspergillus fumigatus strains was studied in an experimental murine model of invasive pulmonary aspergillosis (IPA) and the results were correlated with possession of a putative molecular marker of virulence. Seven strains from different patients with non-invasive or invasive aspergillosis and four environmental strains were typed by PCR with specific primers and scored as positive or negative, according to whether or not a 0.95-kb DNA fragment was amplified. Immunosuppressed mice were inoculated intranasally with A. fumigatus conidia from these different strains. The mortality curves revealed differences in virulence between the strains. The environmental strains produced a weaker infection than the strains from patients and the 0.95-kb-positive patient strains caused significantly higher mortality rates in mice than the 0.95-kb-negative patient strains. These findings support the hypothesis that certain isolates of A. fumigatus are more virulent than others and that their virulence appears to be associated with the 0.95-kb molecular marker.

Animals↗

Multicentric epidemiological study of Aspergillus fumigatus isolates by multilocus enzyme electrophoresis.

The genotypes of 63 isolates of Aspergillus fumigatus obtained from three hospitals in different geographical areas and of eight culture collection strains were determined by multilocus enzyme electrophoresis. Twelve of the 17 enzymatic loci studied were polymorphic, giving rise to 48 different electrophoretic types. The existence of fixed multilocus genotypes, significant heterozygote deficits and excesses at the different loci, and linkage disequilibria within subpopulations strongly suggests a clonal reproduction mode for A. fumigatus. Numerical analysis of the comparison and disposition of the different electrophoretic types demonstrates a significant genetic differentiation between the three sampling sites. However, no correlation could be found between geographical distances and genetic differentiation. On account of the multiple discriminatory markers, multilocus enzyme electrophoresis typing seems to be a very powerful tool for epidemiological and reproductive mode studies of A. fumigatus.

Aspergillosis↗

Comparison of the new API Candida system to the ID 32C system for identification of clinically important yeast species.

API Candida was evaluated in comparison with the ID 32C system for the identification of 619 yeast isolates. The sensitivity of API Candida for the identification of the 15 species it claims to identify with and without additional tests was 97.4% (593 of 609) and 75.2% (458 of 609), respectively. The API Candida system is easy to use and rapid (result in 18 to 24 h).

Candida↗

[Aspergillus fumigatus: from saprophytism to virulence. Phenotypic and genotypic biodiversity].

During the last two decades, deep changes have arised in aspergillosis. Thus, this fungal infection mainly due Aspergillus fumigatus is becoming a serious public health-hazard in the growing population of immunocompromised patients. From literature and their own experience, the authors present a synthesis of phenomenons promoting this evolution: the host predisposing factors, environment and potential contamination sources, then the fungus itself. Genetic research developed into the disease-causing organism could be of major interest in epidemiology of aspergillosis and to identify new targets of prophylaxis.

Aspergillosis↗

Virulence of Aspergillus fumigatus strains investigated by random amplified polymorphic DNA analysis.

A possible relationship between the ability of Aspergillus fumigatus strains to invade tissues and genetic polymorphism was studied by random amplified polymorphic DNA (RAPD) analysis. One hundred randomly designed oligonucleotide decamers were examined with DNA of three reference strains, eight environmental isolates and 21 isolates from two distinct clinical situations: non-invasive aspergillosis (predominantly aspergilloma) and invasive aspergillosis. One primer (OPQ 6) was found to generate a reproducible amplification product that enabled distinction between the two groups according to the presence or absence of a 0.95-kb fragment that correlated with the nature of the infection (non-invasive or invasive) and immune status of the patient. The results indicated that the pathogenicity of A. fumigatus was related not only to the host's immune status but also to the virulence of the strain of A. fumigatus.

Aspergillosis↗

Specific antibody detection in invasive aspergillosis by analytical isoelectrofocusing and immunoblotting methods.

Aspergillus fumigatus antigens have been tested to determine their potential as aids in the diagnosis of invasive aspergillosis (IA). Immunoglobulin G (IgG) antibodies to these antigens were detected by analytical isoelectrofocusing in conjunction with immunoblotting. A total of 12 antigenic fractions, including culture filtrates and surface and mycelial extracts of A. fumigatus, were investigated. Eleven were reactive with serum specimens from patients with aspergilloma, which served as positive controls for the evaluation of a specific IgG response. Eight of 12 antigens showed good responses with serum specimens from patients with allergic bronchopulmonary aspergillosis, which were used to assess the sensitivity of IgG detection. No measurable reactivity was detected in 18 negative control serum specimens, while 11 of 13 patients with proven, highly probable, or probable cases of IA had anti-Aspergillus IgG to multiple antigenic preparations. Patients with IA who were capable of mounting a substantial humoral response to Aspergillus antigens gave an antibody profile with five antigenic preparations which seemed to be characteristic of the disease. Data show that this method is highly sensitive and may allow the selection of fractions which are both highly antigenic and specific for the detection of antibodies to Aspergillus antigens. They also indicate that the use of a spectrum of antigenic molecules is advisable, given the variability observed in the immune responses of individual patients.

Antibodies, Fungal↗

Auxacolor, a new commercial system for yeast identification: evaluation of 182 strains comparatively with ID 32C.

The incidence of deep candidiasis, particularly in immunocompromised patients, and the emergence of less sensitive yeast species to new antifungal agents explain the interest of their rapid identification. A new identification system, Auxacolor (Sanofi Diagnostics Pasteur), has been evaluated, comparatively to ID 32C strip taken in reference (bioMérieux SA). These systems include respectively 13 and 29 carbohydrate assimilation tests. One hundred and sixty-nine strains belonging to 17 common yeast species isolated from biological specimens were identified. Moreover, 13 strains belonging to seven species rarely isolated and not included in the Auxacolor data base were tested. Correct biochemical profiles were obtained with 95.2% of the strains from the first panel. These profiles alone permit correct identification of 62.7% of them (n = 106). The remainders (Candida glabrata, Candida krusei, Candida guilliermondii, Candida inconspicua and Candida lipolytica) require time consuming additional morphological observations for a definitive identification. However, the time needed to obtain the biochemical profiles of these 106 strains was shorter when using Auxacolor: 77.4% of the strains were identified at 24 h with Auxacolor and 47.1% were identified at 24 h with ID 32C. Species from the second panel were not identified (seven strains) or incorrectly identified (six strains). The Auxacolor system was found to be reliable when performed in conjunction with morphological tests and easy to use for the identification of most medically important yeasts.

Evaluation Studies as Topic↗

[A very up-to-date stage in the fate of infectious diseases: parasitic and fungal opportunistic infections].

Opportunistic parasitosis and mycosis are becoming ever more widespread, mainly under the influence of major immunodeficiencies, either acquired (AIDS) or therapeutic. In this general overview, their main aspects, both clinical and epidemiological, are underlined. In terms of epidemiology, three types of phenomena have been observed: 1) emergence of human parasitosis unknown before (microsporidiosis due to Enterocytozoon bieneusi, Encephalitozoom hellem or Septata intestinalis); 2) among the human parasites already known, identification of very pathogenic strains (Toxoplasma gondii, Aspergillus fumigatus, Cryptococcus neoformans); 3) origin probably or certainly nosocomial of certain infections (pneumocystosis; toxoplasmosis and visceral leishmaniasis transmitted during bone-marrow or organ transplantations). The development of deep mycosis (invasive aspergillosis) is particularly promoted by granulopenia and alterations in the phagocytosis. On the other hand, opportunistic protozoosis (toxoplasmosis and leishmaniasis) and helminthiasis (strongyloidosis due to Strongyloides stercolaris) are related, above all, to disorders in cellular immunity (deficit of CD4+, mainly). Finally, several of these infections may be characterised by a variety of clinical pictures and outcome, depending on the contributory factors (immunodeficit or not) which led to the development of the infection.

AIDS-Related Opportunistic Infections↗