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Cystic fibrosis (CF) is the most common inherited genetic disease in Caucasian populations. Besides bacteria, many species of fungi may colonize the respiratory tract of these patients, sometimes leading to true respiratory infections. In this study, an oligonucleotide array capable of identifying 20 fungal species was developed to directly detect fungi in the sputum samples of CF patients. Species-specific oligonucleotide probes were designed from the internal transcribed spacer (ITS) regions of the rRNA operon and immobilized on a nylon membrane. The fungal ITS regions were amplified by PCR and hybridized to the array for species identification. The array was validated by testing 182 target strains (strains which we aimed to identify) and 141 nontarget strains (135 species), and a sensitivity of 100% and a specificity of 99.2% were obtained. The validated array was then used for direct detection of fungi in 57 sputum samples from 39 CF patients, and the results were compared to those obtained by culture. For 16 sputum samples, the results obtained by the array corresponded with those obtained by culture. For 33 samples, the array detected more fungal species than culture did, while the reverse was found for eight samples. The accuracy of the array for fungal detection in sputum samples was confirmed (or partially confirmed) in some samples by cloning and resequencing the amplified ITS fragments. The present array is a useful tool for both the simultaneous detection of multiple fungal species present in the sputa of CF patients and the identification of fungi isolated from these patients.

Resume Le diagnostic de lupus erythemateux dissemine repose sur un faisceau de signes cliniques et biologiques. Au premier chef, la recherche d'anticorps (Ac) anti-acide desoxyribonucleique (ADN) double brin (db). Plusieurs methodes sont disponibles, mais elles ne sont pas interchangeables, car chacune d'entre elles ne detecte qu'une population d'Ac. Comparer les resultats obtenus par huit techniques de routine debouche sur cinq conclusions. (1) L'immunofluorescence indirecte (IFI) sur Crithidia luciliae et le test Farrzyme™ selectionnent les Ac anti-ADN dont l'affinite est la plus forte. (2) La sensibilite de l'enzyme-linked immunosorbent assay et de l'analyse cytofluorimetrique par technologie Luminex™ a l'aide de billes coiffees d'ADN est meilleure que celle de l'IFI sur C. luciliae, mais c'est aux depens de leur specificite. (3) Ce qui est decisif pour que l'ADN capte efficacement les Ac correspondants, ce n'est pas l'organisme dont il provient, mais la qualite de sa presentation dans le test. (4) La contamination de la preparation d'ADN ≪double brin ≫ par de l'ADN ≪ simple brin ≫ ou par de l'acide ribonucleique explique que certains Ac d'affinite negligeable soient abusivement retenus et assimiles a des Ac anti-ADN de forte affinite. (5) Un titre eleve d'Ac et une positivite confirmee par plusieurs techniques indiquent que la maladie se trouve dans une phase active.

Objective Anti–double-stranded DNA (anti-dsDNA) antibodies may contribute to the pathogenesis of glomerulonephritis (GN) by cross-reacting with α-actinin in murine models and in some patients with systemic lupus erythematosus (SLE). We therefore sought to determine possible disease associations with serologic and clinical features and to characterize this new autoantibody specificity. Methods One hundred patients with SLE were recruited into this multicenter study, as well as 100 rheumatic disease controls and 2,100 healthy blood donors. Clinical disease was evaluated by the SLE Disease Activity Index (SLEDAI; excluding the anti-DNA component). Anti-dsDNA antibodies were detected by conventional enzyme-linked immunosorbent assay (ELISA) and by a commercial enzyme immunoassay (EIA). Anti–α-actinin antibodies were detected by ELISA, and their specificity was confirmed by Western blotting and by indirect immunofluorescence using rat kidney sections and mesangial cells as substrates. Highly positive sera were selected for absorption experiments and were affinity-purified for cross-reactivity studies and measurement of antibody avidity. Results Sera from 62 of the SLE patients had anti-dsDNA antibodies; 21 of these sera also had anti–α-actinin antibodies, as compared with 1 of the 38 sera without anti-dsDNA antibodies. Of the 22 patients with anti–α-actinin antibodies, 10 had GN, as compared with 14 of the 78 without anti–α-actinin antibodies (P < 0.01). In patients with GN, anti–α-actinin, but not anti-dsDNA, antibodies correlated with the SLEDAI score (minus the anti-DNA component) and with treatment. The fraction of serum anti-dsDNA antibodies that cross-reacted with α-actinin exhibited high avidity for dsDNA, as determined using a commercial EIA for high-avidity anti-dsDNA antibodies and an in-house conventional ELISA. Conclusion The α-actinin–binding antibodies are significantly associated with GN in SLE. Whether such autoantibodies may anticipate the development of this complication of SLE remains to be verified.

International audience; INTRODUCTION: Most studies dealing with automated hematology analyzers (HAs) and malaria diagnosis are conducted in endemic countries.METHODS: We retrospectively studied cell blood counts (CBCs) performed with Sysmex XE-2100 and XE-5000 HAs in our center (Angers, France) regarding 67 patients returning from endemic areas and infected with various Plasmodium species.RESULTS: In 83% of infected samples with Plasmodium vivax (Pv), ovale (Po), or malariae (Pm), extra clouds of dots were present in neutrophil and/or eosinophil area(s) on routine differential (DIFF) scattergrams. In contrast, samples infected with Plasmodium falciparum (Pf) failed to show such DIFF scattergrams, or any other suggesting malaria infection (0/ 49 pts). Abnormal areas from DIFF scattergrams were related to the presence of mature schizonts and gametocytes, undestroyed by lysis agent, the latter not observed in Pf-infected patients from our series. The internal parameter WBC[DIFF]-WBC[BASO] raised in parallel to parasitemia in Pv, Po, and Pm samples but could not be used as a surrogate for parasitemia. In Pf infection, reticulocyte/ immature reticulocyte fraction (IRF) ratio showed a significant correlation with parasitemia (PCONCLUSION: Using SYSMEX analyzers, Pv, Po, and Pm infections are easy to ascertain as DIFF scattergrams are almost specific (specificity=99.9%). Pf infection diagnosis by CBC may be a more promising tool.

International audience