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BACKGROUND: Globally distributed with variable prevalence depending on geography, toxoplasmosis is a zoonosis caused by an obligate intracellular protozoan parasite, Toxoplasma gondii. This disease is usually benign but poses a risk for immunocompromised people and for newborns of mothers with a primary infection during pregnancy because of the risk of congenital toxoplasmosis (CT). CT can cause severe damage to fetuses-newborns. To our knowledge, no study has been conducted in sub-Saharan Africa on toxoplasmosis seroprevalence, seroconversion and CT in a large longitudinal cohort and furthermore, no observation has been made of potential relationships with malaria. METHODS: We performed a retrospective toxoplasmosis serological study using available samples from a large cohort of 1,037 pregnant women who were enrolled in a malaria follow-up during the 2008-2010 period in a rural area in Benin. We also used some existing data to investigate potential relationships between the maternal toxoplasmosis serological status and recorded malaria infections. RESULTS: Toxoplasmosis seroprevalence, seroconversion and CT rates were 52.6%, 3.4% and 0.2%, respectively, reflecting the population situation of toxoplasmosis, without targeted medical intervention. The education level influences the toxoplasmosis serological status of women, with women with little or no formal education have greater immunity than others. Surprisingly, toxoplasmosis seropositive pregnant women tended to present lower malaria infection during pregnancy (number) or at delivery (presence) and to have lower IgG levels to Plasmodium falciparum Apical Membrane Antigen 1, compared to toxoplasmosis seronegative women. CONCLUSIONS: The high toxoplasmosis seroprevalence indicates that prevention against this parasite remains important to deploy and must be accessible and understandable to and for all individuals (educated and non-educated). A potential protective role against malaria conferred by a preexisting toxoplasmosis infection needs to be explored more precisely to examine the environmental, parasitic and/or immune aspects.
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Anticuerpos Antiprotozoarios/sangre , Malaria Falciparum/epidemiología , Plasmodium falciparum/aislamiento & purificación , Complicaciones Parasitarias del Embarazo/epidemiología , Mujeres Embarazadas , Toxoplasma/aislamiento & purificación , Toxoplasmosis/epidemiología , Adolescente , Adulto , Anticuerpos Antiprotozoarios/inmunología , Benin/epidemiología , Femenino , Humanos , Recién Nacido , Malaria Falciparum/sangre , Malaria Falciparum/parasitología , Embarazo , Complicaciones Parasitarias del Embarazo/parasitología , Estudios Retrospectivos , Estudios Seroepidemiológicos , Toxoplasmosis/sangre , Toxoplasmosis/parasitología , Adulto JovenRESUMEN
Serum (1â3)-ß-D-glucan (BDG), an pan fungal antigen, is detected in some invasive fungal diseases (IFDs). We compared two commercial kits, the Fungitell assay (FA) (colorimetric) and the Wako assay (WA) (turbidimetric) over a 4-month period to prospectively test 171 patients who mainly had hematological conditions (62%) and experienced episodes (n = 175) of suspected invasive fungal infection. Twenty-three episodes due to BDG-producing fungi were diagnosed (pneumocystosis, n = 12; invasive aspergillosis, n = 5; candidemia, n = 3; invasive fusariosis, n = 2; hepato-splenic candidiasis, n = 1).Both assays provided similar areas under the curves (AUC = 0.9). Using the optimized positivity thresholds (≥120 pg/ml for FA and ≥ 4 pg/ml for WA), the sensitivity and specificity were 81.8% (CI95: 61.5-92.7), 94.8% (90.1-97.3) for FA and 81.8% (61.5-92.7), 95.4% (90.9-97.8) for WA. Negative predictive value was 97.3% (93.3-99.0) for both tests. If the manufacturer's positivity threshold (≥11 pg/ml) was applied, the WA sensitivity decreased to 50%. Among 71 patients with bacterial infections, 21.1% were FA-positive and 5.6% were WA-positive (p < 10-2).The WA performed similarly as compared to the FA with an optimized cutoff value. The WA is a single sample test that is clinically relevant when a prompt therapeutic decision is required. LAY SUMMARY: Serum (1â3)-ß-D-glucan testing is dominated by two kits including Fungitell colorimetric assay (FA) and the Wako turbidimetric assay (WA). We compared them prospectively and observed that they both perform similarly when selecting their optimal threshold (≥120 pg/ml for FA and ≥ 4 pg/ml for WA).
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Colorimetría/métodos , Técnicas y Procedimientos Diagnósticos , Inmunoturbidimetría/métodos , Infecciones Fúngicas Invasoras/diagnóstico , Micosis/diagnóstico , Proteoglicanos/sangre , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
Amoebic liver abscess (ALA) is regularly seen in travelers or immigrants from tropical countries. The diagnosis relies on liver imaging that is not specific and on the detection of anti-Entamoeba histolytica antibodies, which cannot distinguish an acute from a former infection. We tested whether E. histolytica DNA detection in serum can improve the diagnosis of ALA. We retrospectively tested available serum samples taken from patients with ALA and non-ALA space-occupying lesions of the liver between 1 January 2010 and 30 November 2019. The quantitative PCR (qPCR) assay tested specifically amplifies a 99-bp fragment of the small-subunit rRNA gene of E. histolytica We analyzed 76 samples (19 ALA and 57 non-ALA samples) collected from 76 patients within 6 days before and after the antiamoebic treatment. Serum qPCR results were positive for 17 of 19 ALA patients and for none of the control patients (sensitivity and specificity were 89.5% and 100%, respectively). In parallel, the sensitivity and specificity of anti-E. histolytica antibody detection were 100% and 89.5%, respectively. The two false-negative qPCR results may be explained by ongoing metronidazole treatment or a possible persistent seropositivity that was not caused by the current liver abscess. Additionally, of 12 abscess pus aspirates (5 from ALA and 7 from non-ALA samples) tested, 5 were qPCR positive and 7 were qPCR negative, with concordant results in serum. This study demonstrates that cell-free circulating E. histolytica DNA can be detected in serum in ALA. This may assist in both positive diagnoses and treatment efficacy follow-up. The origin of this circulating DNA remains to be investigated.
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Entamoeba histolytica , Absceso Hepático Amebiano , Anticuerpos Antiprotozoarios , Entamoeba histolytica/genética , Humanos , Absceso Hepático Amebiano/diagnóstico , Estudios Retrospectivos , Pruebas SerológicasAsunto(s)
Anticuerpos Antifúngicos/sangre , Hidradenitis Supurativa/inmunología , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inflamación/inmunología , Saccharomyces cerevisiae/fisiología , Adulto , Anciano , Femenino , Francia/epidemiología , Hidradenitis Supurativa/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios SeroepidemiológicosRESUMEN
BACKGROUND: A high incidence of acute hepatitis C virus (HCV) (AHCV) infection has been reported among at-risk HIV-negative MSM. The optimal strategy for early diagnosis of AHCV in this population is not clearly defined. METHODS: In the ANRS IPERGAY PrEP trial, among high-risk HIV-negative MSM, HCV serology and serum alanine aminotransferase (ALT) were used for screening at enrollment and during follow-up. Behavioral risk factors were compared at baseline between participants who were diagnosed with AHCV during the study compared with those who did not. In participants with a positive HCV serology, we used stored sera to perform the following tests at diagnosis and on previous visits: HCV-antibodies rapid tests, plasma HCV viral load and HCV antigen immunoassay. We evaluated the sensitivity of each test for AHCV diagnosis. RESULTS: Among 429 enrolled participants, 14 were diagnosed with AHCV infection, with a median follow-up of 2.1 (interquartile range, 1.5-2.8) years. AHCV incidence was 1.40 per 100 person-years (95% confidence interval, 0.74-2.39). Patients with AHCV reported a significantly higher number of sexual acts and/or partners, and more frequent recreational drug use at baseline. At the prior visit before AHCV diagnosis (median of 2 months earlier), sensitivities of HCV RNA and HCV antigen tests were, respectively, 100 and 89%, whereas none of the patients had a positive serology, and only 25% had elevated ALT. CONCLUSION: HCV antigen and RNA tests were positive within a median of 2 months before the detection of antibodies and ALT elevation. These tests could be considered for HCV screening in high-risk MSM.
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Infecciones por VIH/prevención & control , Hepatitis C/diagnóstico , Hepatitis C/epidemiología , Enfermedad Aguda , Adulto , Alanina Transaminasa/sangre , Diagnóstico Precoz , Infecciones por VIH/complicaciones , Hepatitis C/transmisión , Anticuerpos contra la Hepatitis C/sangre , Antígenos de la Hepatitis C/sangre , Homosexualidad Masculina , Humanos , Masculino , Profilaxis Pre-Exposición , ARN Viral/sangre , Factores de Riesgo , Carga ViralRESUMEN
BACKGROUND: Time to positivity (TTP) and differential time to positivity (DTTP) between central and peripheral blood cultures are commonly used for bacteraemia to evaluate the likelihood of central venous catheter (CVC)-related bloodstream infection. Few studies have addressed these approaches to yeast fungaemia. OBJECTIVES: This study aimed to evaluate TTP and DTTP to assess CVC-related yeast fungaemia (CVC-RYF). PATIENTS/METHODS: We retrospectively analysed the results from 105 adult patients with incident fungaemia, with CVC removed and cultured, collected from 2010 to 2017. The bottles were incubated in a BioMérieux BacT/ALERT 3D and kept for at least 5 days. RESULTS: Of the 105 patients included, most were oncology patients (85.7%) and had of long-term CVC (79.6%); 32 (30.5%) had a culture-positive CVC (defined as CVC-RYF) with the same species as in blood culture, and 69.5% had culture-negative CVC (defined as non-CVC-RYF, NCVC-RYF). Candida albicans represented 46% of the episodes. The median TTP was statistically different between CVC-RYF and NCVC-RYF (16.8 hours interquartile range (IQR) [9.7-28.6] vs 29.4 hours [IQR 20.7-41.3]; P = .001). A TTP <10 hours had the best positive likelihood ratio (21.5) for CVC-RYF, although the sensitivity was only 28%. DTTP was available for 52 patients. A DTTP >5 hours had a sensitivity of 100% and a specificity of 71% for CVC-RYF. CONCLUSIONS: Since the median TTP was 17 hours and the most performing DTTP >5 hours, these delays are too long to take a decision in the same operational day. More rapid methods for detecting infected catheters should be tested to avoid unnecessary CVC withdrawal.
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Candida albicans/aislamiento & purificación , Candidemia/sangre , Infecciones Relacionadas con Catéteres/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cultivo de Sangre , Cateterismo Venoso Central , Femenino , Hospitales Universitarios , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
Primary Sjögren's syndrome (pSS) is characterized by B cell hyperactivation, production of autoantibodies and increased risk of B cell lymphomas. Serological profile of Epstein-Barr virus (EBV) reactivation and increase EBV DNA levels in exocrine glands are observed in pSS, but whether these abnormalities are accompanied with disturbed systemic EBV control or have any association with pSS activity remains to be investigated. In this observational study, we initially explored anti-EBV antibodies and cell-free DNA in 395 samples from a cross-sectional plasma collection of pSS patients included in ASSESS French national cohort. Results were assessed in relation with disease activity. Further, to assess cell-associated EBV DNA we organized a case-control study including 20 blood samples from pSS patients followed in University Hospital Center of Montpellier. Results were compared with matched controls. Robust response against EBV early antigen (EA) was observed in pSS patients with anti-SSA/B (Sjögren's syndrome A and B) and anti-SSA autoantibodies compared to anti-SSA/B negatives (P < 0.01 and P = 0.01, respectively). Increased beta-2 microglobulin, kappa and lambda light chains, and immunoglobulin G levels were more frequently observed in anti-EA seropositive pSS subjects compared to anti-EA negative subjects (P < 0.001; P = 0.001; P = 0.003, respectively). Beta-2 microglobulin was independently associated with anti-EA positivity in multivariate analysis (P < 0.001). Plasma cell-free EBV DNA and EBV cellular reservoir was not different between pSS patients and controls. We conclude that serological evidence of EBV reactivation was more frequently observed and more strongly associated with anti-SSA/B status and B cell activation markers in pSS. However, serological profile of EBV reactivation was not accompanied by molecular evidence of systemic EBV reactivation. Our data indicated that EBV infection remains efficiently controlled in the blood of pSS patients.
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Anticuerpos Antinucleares/sangre , Anticuerpos Antivirales/sangre , Infecciones por Virus de Epstein-Barr/complicaciones , Herpesvirus Humano 4/fisiología , Síndrome de Sjögren/inmunología , Activación Viral , Adulto , Anciano , Autoantígenos/inmunología , Linfocitos B/inmunología , Biomarcadores , Estudios de Casos y Controles , ADN Viral/análisis , ADN Viral/sangre , Infecciones por Virus de Epstein-Barr/virología , Glándulas Exocrinas/virología , Femenino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/inmunología , Humanos , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Ribonucleoproteínas/inmunología , Síndrome de Sjögren/sangre , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/virología , Microglobulina beta-2/análisis , Antígeno SS-BRESUMEN
[This corrects the article DOI: 10.3389/fmicb.2018.02369.].
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Background: The protozoan Toxoplasma gondii presents a risk for reactivation of latent cysts in immunocompromised patients. Anti-T. gondii antibodies are therefore usually screened before chemotherapy or transplantation to propose prophylactic measures against this parasite. We analyzed the results obtained in our hospital to study the epidemiological trend of T. gondii infection. Methods: We collected all the anti-Toxoplasma antibody titers from January 1, 1997 to December 31, 2013 using the Platelia IgG ELISA assay (Bio-Rad). The results were classified as positive when titers reached a concentration of ≥10 UI/ml. Only the first result obtained at entry for each patient was considered. T. gondii seroprevalence was estimated using a multivariate logistic regression model accounting for age, sex, and year in which the sample was collected. Results: A total of 21,480 patient samples were analyzed. The seroprevalence continuously decreased over time, from 64.5% in 1997 to 54.7% in 2013 (i.e., an average of 1.3% per year, p < 0.001). The decrease was 5.0% per year for patients <20 years. After 2013, the model predicts that the seroprevalence would continuously decrease. We also observed a higher proportion of seropositive men than women in the 15- to 45-year-old group (58.5% versus 52.0%, p < 10-3). Conclusion: The overall seroprevalence of toxoplasmosis at our hospital showed an accelerating downward trend over 17 years. The reason for this continuous decline is likely associated with the lower parasite presence within meat. Thus, although young immunocompromised patients are increasingly less at risk of reactivation in the near future, older immunocompromised patients will remain at high risk of reactivation. The reasons of the higher prevalence in men remain to be explored.
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The performance of antigen galactomannan (GM) for diagnosing invasive aspergillosis (IA) is hampered by the occurrence of false-positive results. Quantitative PCR has been proposed to improve the diagnosis of IA. Therefore, we analyzed the value of performing a PCR test to the GM-positive serum sample. Using a quantitative PCR assay specific for Aspergillus fumigatus 28S ribosomal DNA, we retrospectively tested 422 GM-positive (Platelia Bio-Rad kit) serum samples collected over 1 year from 147 patients. The cases were classified based on EORTC criteria as "proven," "probable," and "no-IA" before availability of the PCR results. After exclusion of 65 samples for non-reproducibility of GM positivity (n = 62) or PCR inhibition (n = 3), 75 (21.0%) of the remaining 357 samples were PCR-positive. GM and fungal DNA showed a significantly positive correlation (p < 0.0001, R2 = 0.27, slope = 0.98 ± 0.19). At least one PCR-positive result was observed in 63.3% (31/49) of IA patients and in 13.2% (13/98) of non-IA patients (p < 0.0001). The PCR positivity was also associated with the presence of other microbiological criteria among the 44 patients with IA and complete mycological workup (p = 0.014), as well as a higher mortality rate at six months among the 135 patients with hematological conditions (p = 0.0198). Overall, we found a quantitative correlation between serum GM and circulating DNA with an increased likelihood of IA when both were positive. A PCR-positive result also supported a higher fungal load when GM was already positive. We advocate adding a PCR test for every confirmed GM-positive serum sample.
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Pneumocystis jirovecii is an airborne human-specific ascomycetous fungus responsible for Pneumocystis pneumonia (PCP) in immunocompromised patients, affecting >500,000 patients per year (www.gaffi.org). The understanding of its epidemiology is limited by the lack of standardised culture. Recent genotyping data suggests a limited genetic diversity of P. jirovecii. The objective of the study was to assess the diversity of P. jirovecii across European hospitals and analyse P. jirovecii diversity in respect to clinical data obtained from the patients. Genotyping was performed using six already validated short tandem repeat (STR) markers on 249 samples (median: 17 per centre interquartile range [11-20]) from PCP patients of 16 European centres. Mixtures of STR markers (i.e., ≥2 alleles for ≥1 locus) were detected in 67.6% (interquartile range [61.4; 76.5]) of the samples. Mixture was significantly associated with the underlying disease of the patient, with an increased proportion in HIV patients (78.3%) and a decreased proportion in renal transplant recipients (33.3%) (p<0.001). The distribution of the alleles was significantly different (p<0.001) according to the centres in three out of six markers. In analysable samples, 201 combinations were observed corresponding to 137 genotypes: 116 genotypes were country-specific; 12 in two; six in three; and two in four and one in five countries. Nine genotypes were recorded more than once in a given country. Genotype 123 (Gt123) was significantly associated with France (14/15, p<0.001) and Gt16 with Belgium (5/5, p<0.001). More specifically, Gt123 was observed mainly in France (14/15/16 patients) and in renal transplant patient (13/15). Our study showed the wide population diversity across Europe, with evidence of local clusters of patients harbouring a given genotype. These data suggest a specific association between genotype and underlying disease, with evidence of a different natural history of PCP in HIV patients and renal transplant recipients.
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ADN de Hongos/genética , Técnicas de Genotipaje/métodos , Pneumocystis carinii/clasificación , Neumonía por Pneumocystis/microbiología , Adulto , Anciano , Europa (Continente) , Femenino , Variación Genética , Humanos , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Filogenia , Filogeografía , Pneumocystis carinii/genética , Pneumocystis carinii/aislamiento & purificaciónRESUMEN
BACKGROUND: Human T-cell lymphotropic virus type 1 and 2 (HTLV-1/2) immunoassays are used for blood screen- ing from blood products, milk, and organ donors. METHODS: We assessed the performance of the DiaSorin Liaison® XL murex recHTLV-I/II immunoassay relative to the Abbott Architect® rHTLV-I/II immunoassay and with the Innogenetics immunoblot as confirmation. RESULTS: A panel of HTLV positive (n = 66) and negative (n = 30) sera was tested in both techniques within the same freeze/thaw cycle. The specificity and sensitivity of DiaSorin immunoassay were 100% and 78.8%, respectively. Abbott and DiaSorin immunoassays showed a correlation in chemiluminiscent signals to cutoff (S/CO) (Pearson r = 0.92). Half of the samples (34/66) from the seropositive panel were not confirmed by immunoblot (S/CO < 5 in both techniques). CONCLUSIONS: Our data confirmed that the DiaSorin Liaison® XL murex recHTLV-I/II immunoassay is an effective platform for HTLV screening. Due to false-positive reaction, especially for samples with low S/CO, each seropositive sample should be confirmed by immunoblot.
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Anticuerpos Antivirales/análisis , Infecciones por HTLV-I/diagnóstico , Virus Linfotrópico T Tipo 2 Humano , Inmunoensayo , Donantes de Sangre , Reacciones Falso Positivas , Virus Linfotrópico T Tipo 1 Humano , Humanos , Pruebas Inmunológicas , Sensibilidad y Especificidad , SueroRESUMEN
Tinea capitis (TC) is a highly contagious fungal infection of the scalp due to dermatophytes in children. To obtain information on the epidemiology of TC in the urban area of Paris, we analysed the microbiological results of 3090 patients seen with suspected TC from October 2010 to September 2015 at Saint Louis hospital, Paris, France. A peak of TC was observed in 3-6 year-old children, followed by a progressive decrease until 16 years of age. Of the 1311 positive cultures, 95% (1246) yielded one of the three anthropophilic species [Trichophyton tonsurans (33.5%), Trichophyton soudanense (38.3%), or Microsporum audouinii (28.2%)]. When considering one TC case per family, we observed a significant increase of T. tonsurans (P = .018) during these 5 years. The increase was more pronounced (P = .0047) in patients of West-African descent (n = 666), and was at the expense of M. audouinii and T. soudanense. On the other hand, the Caribbean patients (n = 85) remained predominantly (72.9%) infected by T. tonsurans. Our results show a better virulence of T. tonsurans over other species as already reported. Since T. tonsurans has not been reported in Africa, the infection of patients of West-African descent probably took place in the Paris area by exchanges with Caribbean patients. This increase of TC due to T. tonsurans was observed in the context of griseofulvin being the only licensed paediatric treatment for TC in France, which should deserve reappraisal because terbinafine may be more efficacious.
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Tiña del Cuero Cabelludo/epidemiología , Tiña del Cuero Cabelludo/microbiología , Trichophyton/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antifúngicos/uso terapéutico , Niño , Preescolar , Femenino , Griseofulvina/uso terapéutico , Humanos , Lactante , Masculino , Microsporum/aislamiento & purificación , Persona de Mediana Edad , Naftalenos/uso terapéutico , Paris/epidemiología , Estudios Retrospectivos , Terbinafina , Tiña del Cuero Cabelludo/diagnóstico , Tiña del Cuero Cabelludo/tratamiento farmacológico , Trichophyton/patogenicidad , Virulencia , Adulto JovenRESUMEN
In a prospective bicentric study, Pneumocystis jirovecii excretion and diffusion was explored in air samples collected in the rooms occupied by 17 Pneumocystis-colonized patients. P. jirovecii DNA was detected by real-time PCR in the air collected from 3 patients' rooms (17.6%), with identical genotypes in corresponding clinical and air samples. Pneumocystis DNA was detected for 2/3 patients with autoimmune disease treated with corticosteroids versus 1/6 patients with hematologic disease and 0/5 kidney transplant recipients. These data confirm the possible excretion of the fungus by Pneumocystis-colonized patients and thus bring additional arguments for the prevention of airborne transmission in hospital wards.
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Microbiología del Aire , Infección Hospitalaria/transmisión , Pneumocystis carinii/aislamiento & purificación , Pneumocystis carinii/fisiología , Neumonía por Pneumocystis/microbiología , Neumonía por Pneumocystis/transmisión , Adulto , Anciano , Infección Hospitalaria/microbiología , ADN de Hongos/genética , ADN de Hongos/aislamiento & purificación , Femenino , Genotipo , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Pneumocystis carinii/genética , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Riesgo , Adulto JovenRESUMEN
Pneumocystis jirovecii is an unculturable fungus and the causative agent of Pneumocystis pneumonia, a life-threatening opportunistic infection. Although molecular diagnosis is often based on the detection of mtLSU rRNA mitochondrial gene, the number of copies of mitochondrial genes had not been investigated. We developed and optimized six real-time PCR assays in order to determine the copy number of four mitochondrial genes (mtSSU rRNA, mtLSU rRNA, NAD1, and CYTB) in comparison to nuclear genome (DHPS and HSP70) and tested 84 bronchoalveolar fluids of patients at different stages of the infection. Unexpectedly, we found that copy number of mitochondrial genes varied from gene to gene with mtSSU rRNA gene being more represented (37 copies) than NAD1 (23 copies), mtLSU rRNA (15 copies) and CYTB (6 copies) genes compared to nuclear genome. Hierarchical clustering analysis (HCA) allowed us to define five major clusters, significantly associated with fungal load (p = 0.029), in which copy number of mitochondrial genes was significantly different among them. More importantly, copy number of mtLSU rRNA, NAD1, and CYTB but not mtSSU rRNA differed according to P. jirovecii physiological state with a decreased number of copies when the fungal load is low. This suggests the existence of a mixture of various subspecies of mtDNA that can harbor different amplification rates. Overall, we revealed here an unexpected variability of P. jirovecii mtDNA copy number that fluctuates according to P. jirovecii's physiological state, except for mtSSU that is the most stable and the most present mitochondrial gene.
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BACKGROUND: Invasive wound mucormycosis (IWM) is associated with an extremely poor outcome among critically ill burn patients. We describe the detection of circulating Mucorales DNA (cmDNA) for the early diagnosis of IWM in those patients and report the potential value of detecting cmDNA for treatment guidance. METHODS: Severely ill burn patients admitted to our tertiary referral center between October 2013 and February 2016 were included. Retrospective plasma samples were tested for the presence of cmDNA by quantitative real-time polymerase chain reaction (qPCR). Patients were then prospectively screened twice a week, and liposomal amphotericin-B therapy initiated based on a positive qPCR. The primary endpoint was the time between cmDNA detection and standard diagnosis. Secondary endpoints were the time from cmDNA detection and treatment initiation and mortality. RESULTS: Seventy-seven patients (418 samples) were included. The average age was 46 (28-60) years, abbreviated burn severity index was 8 (7-10), and simplified acute physiology score was 33 (23-46). The total body surface area was 33% (22%-52%). cmDNA was detected 11 (4.5-15) days before standard diagnosis. The in-hospital mortality was 62% for patients with IWM and 24% for those without (P = .03). The mortality due to IWM was 80% during period A and 33% during period B (P = .46). CONCLUSIONS: This study suggests that the detection of cmDNA allows earlier diagnosis of IWM in severely ill burn patients and earlier initiation of treatment. Further studies are needed to confirm the impact of earlier treatment initiation on patient outcome.
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Quemaduras/microbiología , ADN de Hongos/sangre , Mucorales/genética , Mucormicosis/diagnóstico , Adulto , Anciano , Quemaduras/complicaciones , Quemaduras/epidemiología , Enfermedad Crítica , Diagnóstico Precoz , Femenino , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Mucormicosis/complicaciones , Mucormicosis/epidemiología , Técnicas de Tipificación Micológica , Estudios RetrospectivosRESUMEN
Droplet digital PCR (ddPCR) after DNA digestion yielded a 28S rDNA copy number of 61 to 86 copies/genome when testing 10 unrelated Aspergillus fumigatus isolates, higher than with quantitative PCR. Unfortunately, ddPCR after DNA digestion did not improve the sensitivity of our PCR assay when testing serum patients with invasive aspergillosis.
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Aspergillus fumigatus/genética , Variaciones en el Número de Copia de ADN , ADN Ribosómico/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Aspergilosis/diagnóstico , Aspergilosis/microbiología , ADN Ribosómico/aislamiento & purificación , Humanos , ARN Ribosómico 28S/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/instrumentación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sensibilidad y EspecificidadRESUMEN
During Epstein-Barr virus (EBV) latency, the EBV genome is largely silenced by methylation. This silencing is overturned during the switch to the lytic cycle. A key event is the production of the viral protein Zta which binds to three Zta-response elements (ZRE) from the Rta promoter (Rp), two of which (ZRE2 and ZRE3) include three CpG motifs methylated in the latent genome. The bisulphite pyrosequencing reaction was used to quantify the methylation of ZRE2, ZRE3a, and ZRE3b in EBV-positive cell lines and in ex vivo samples of EBV-related diseases, in order to assess whether the level of methylation in these ZREs could provide additional information to viral DNA load and serology in the characterization of EBV-associated diseases. In PBMC from two patients with infectious mononucleosis, over time Rp became increasingly methylated whereas EBV load decreased. In tonsil from patients with chronic tonsillitis, the methylation was less than in EBV-associated tumors, regardless of the viral load. This was even more striking when only the ZRE3a and ZRE3b were considered since some samples presented unbalanced profiles on ZRE2. EBV reactivation in cell culture showed that the reduction in the overall level of methylation was closely related to the production of unmethylated virions. Thus, an assessment of the level of methylation may help to better characterize EBV replication in PBMC and in biopsies with high EBV load, during infectious mononucleosis and EBV-associated cancers. J. Med. Virol. 88:1814-1820, 2016. © 2016 Wiley Periodicals, Inc.
Asunto(s)
Metilación de ADN , Infecciones por Virus de Epstein-Barr/virología , Proteínas Inmediatas-Precoces/química , Proteínas Inmediatas-Precoces/genética , Regiones Promotoras Genéticas , Transactivadores/química , Transactivadores/genética , Carga Viral , Línea Celular , ADN Viral/genética , Infecciones por Virus de Epstein-Barr/sangre , Infecciones por Virus de Epstein-Barr/inmunología , Regulación Viral de la Expresión Génica , Genoma Viral , Herpesvirus Humano 4/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Proteínas Inmediatas-Precoces/metabolismo , Mononucleosis Infecciosa/virología , Leucocitos Mononucleares/virología , Tonsila Palatina/virología , Saliva/virología , Transactivadores/metabolismo , Latencia del Virus/genéticaRESUMEN
Invasive fungal infections (IFIs) are life-threatening complications of hematological malignancies that must be diagnosed early to allow effective treatment. Few data are available on the performance of serum (1-3)-ß-D-glucan (BG) assays for diagnosing IFI in patients with hematological malignancies admitted to the intensive care unit (ICU). In this study, 737 consecutive patients with hematological malignancies admitted to 17 ICUs routinely underwent a BG assay at ICU admission. IFIs were diagnosed using standard criteria applied by three independent specialists. Among the 737 patients, 439 (60%) required mechanical ventilation and 273 (37%) died before hospital discharge. Factors known to alter BG concentrations were identified in most patients. IFIs were documented in 78 (10.6%) patients (invasive pulmonary aspergillosis, n = 54; Pneumocystis jirovecii pneumonia, n = 13; candidemia, n = 13; and fusarium infections, n = 3). BG concentrations (pg/mL) were higher in patients with than without IFI (144 (77-510) vs. 50 (30-125), < 0.0001). With 80 pg/mL as the cutoff, sensitivity was 72%, specificity 65%, and area-under-the-curve 0.74 (0.68-0.79). Assuming a prevalence of 10%, the negative and positive predictive values were 94% and 21%. By multivariable analysis, factors independently associated with BG > 80 pg/mL were IFI, admission SOFA score, autologous bone-marrow or hematopoietic stem-cell transplantation, and microbiologically documented bacterial infection. In conclusion, in unselected critically ill hematology patients with factors known to affect serum BG, this biomarker showed only moderate diagnostic performance and rarely detected IFI. However, the negative predictive value was high. Studies are needed to assess whether a negative BG test indicates that antifungal de-escalation is safe.
Asunto(s)
Enfermedad Crítica/terapia , Neoplasias Hematológicas/complicaciones , Infecciones Fúngicas Invasoras/sangre , beta-Glucanos/sangre , Adulto , Biomarcadores/sangre , Enfermedad Crítica/mortalidad , Femenino , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Infecciones Fúngicas Invasoras/complicaciones , Infecciones Fúngicas Invasoras/diagnóstico , Tiempo de Internación/estadística & datos numéricos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Proteoglicanos , Sensibilidad y EspecificidadRESUMEN
Candida glabrata is a major pathogenic yeast in humans that is known to rapidly acquire resistance to triazole and echinocandin antifungal drugs. A mutator genotype (MSH2 polymorphism) inducing a mismatch repair defect has been recently proposed to be responsible for resistance acquisition in C. glabrata clinical isolates. Our objectives were to evaluate the prevalence of antifungal resistance in a large cohort of patients in Saint-Louis hospital, Paris, France, some of whom were pre-exposed to antifungal drugs, as well as to determine whether MSH2 polymorphisms are associated with an increased rate of fluconazole or echinocandin resistance. We collected 268 isolates from 147 patients along with clinical data and previous antifungal exposure. Fluconazole and micafungin minimal inhibition concentrations (MICs) were tested, short tandem repeat genotyping was performed, and the MSH2 gene was sequenced. According to the European Committee on Antimicrobial Susceptibility breakpoints, 15.7% of isolates were resistant to fluconazole (MIC > 32 mg/L) and 0.7% were resistant to micafungin (MIC > 0.03 mg/L). A non-synonymous mutation within MSH2 occurred in 44% of the isolates, and 17% were fluconazole resistant. In comparison, fluconazole resistant isolates with no MSH2 mutation represented 15% (P = 0.65). MSH2 polymorphisms were associated with the short tandem repeat genotype. The rate of echinocandin resistance is low and correlates with prior exposure to echinocandin. The mutator genotype was not associated with enrichment in fluconazole resistance but instead corresponded to rare and specific genotypes.