PubMed Health⌕ Search

Biomedical subjects

A Dewilde

Publications and source records attributed to A Dewilde.

At least 19 recordsLinked to original sources

Routine CMV screening during pregnancy.

Cytomegalovirus (CMV) screening during pregnancy has been widely discussed for several years, but still no consensus has been agreed. With a number of live births of 750,000 per year in France, we would expect 7500 infected infants at birth per year (rate of congenital infection of 1%). Among infected infants at birth, the number of severely infected foetuses would be approximately 75, the number of infants with severe sequelae would be 480, 675 approximately would present with hearing loss and the number of asymptomatic infants would be 6270. Five different preventive methods for congenital CMV infection are possible: (1) Routine CMV screening at the beginning of pregnancy for primary prevention. (2) Secondary prevention by antenatal diagnosis of congenital CMV infection complications. (3) Tertiary prevention by serological testing during pregnancy. (4) Tertiary prevention by serological screening at birth. (5) Tertiary prevention: Hearing loss screening at birth. The aims of this review are to define the advantages and disadvantages of these different methods of CMV screening during pregnancy and to determine if the current available information would make systematic testing acceptable.

Cytomegalovirus Infections↗

Role of viruses and atypical bacteria in exacerbations of asthma in hospitalized children: a prospective study in the Nord-Pas de Calais region (France).

We studied the role of viruses and atypical bacteria in children hospitalized with exacerbated asthma by a prospective study of children with acute asthma admitted to the Department of Pediatrics in Lille, and to 15 hospitals in the Nord-Pas de Calais region, from October 1, 1998-June 30, 1999. We included children aged 2-16 years with active asthma, defined as three or more recurrent episodes of reversible wheezing. The severity of asthma and of asthmatic exacerbations was recorded. Immunofluorescence assays (IFA) on nasopharyngeal secretions (NPS), serological tests, or both, were used for detection of influenza virus, respiratory syncytial virus (RSV), adenovirus, parainfluenza virus, and coronavirus. Polymerase chain reaction (PCR) assays on NPS were used for rhinovirus and enterovirus. Serological tests for Chlamydia pneumoniae and Mycoplasma pneumoniae were performed. A control group of asymptomatic asthmatic outpatients was examined for respiratory viruses (using IFA and PCR). Eighty-two symptomatic children (mean age, 7.9 years) were examined. Viruses were detected in 38% (enterovirus, 15.8%; rhinovirus, 12%; RSV, 7.3%). Serological tests for atypical bacteria were positive in 10% of patients (C. pneumoniae, 5%; M. pneumoniae, 5%). Among the 27 control subjects (mean age, 7.9 years), one PCR was positive for enterovirus. There was no correlation between severity of chronic asthma or asthmatic exacerbations and the diagnosis of infection. Atypical bacterial pathogen infections were linked with prolonged asthmatic symptoms. In conclusion, we confirmed the high incidence of viral infection in acute exacerbations of asthma, especially enteroviruses or rhinoviruses. Persistent clinical features were more frequently associated with atypical bacterial infections, suggesting that these infections should be investigated and treated in cases of persistent asthmatic symptoms.

Adolescent↗

Value of human papillomavirus testing after conization by loop electrosurgical excision for high-grade squamous intraepithelial lesions.

OBJECTIVE: The aim of the study was to evaluate human papillomavirus (HPV) testing during the follow-up of patients after conization by loop electrosurgical excision for high-grade squamous intraepithelial lesion. METHODS: A prospective study was conducted on 205 patients who underwent conization for high-grade squamous intraepithelial lesion (CIN 2 or 3). Loop electrosurgical excision procedure (LEEP) was used in all cases. High-risk HPV testing was realized by the Hybrid Capture II system before and 3 months after conization. RESULTS: Of the 205 patients, 193 (94.1%) were positive for the HPV test before conization. Seventy-one were HPV positive after conization (34.6%). The margins were positive in 36.1%. Residual disease was observed in 27 cases (13.2%). Four patients (2%) developed a recurrence after a mean follow-up of 18.1 months (+/-12). There was no correlation between pretreatment HPV testing and the residual disease or recurrence. Patients with positive margins were significantly more likely to have residual disease than those with negative margins (P < 0.0001). Residual disease was more likely to occur when the posttreatment HPV test was positive (P < 10(-7)). All recurrences were observed in patients with a positive posttreatment HPV test (P < 0.05). Residual disease and recurrence were correctly predicted with a sensitivity of 81 and 100%, respectively, and a negative predictive value of 96 and 100%. CONCLUSION: Posttreatment HPV testing could be useful in the follow-up of patients after conization. In case of negative posttreatment HPV testing, the frequency of follow-up could be reduced, particularly in those patients with free margins.

Adolescent↗

[Purpura fulminans and coxsackie B2 co-infection].

INTRODUCTION: During septic shock in children, myocardial deficiency usually lasts 3 to 6 days. When prolonged, an other etiology should be looked for. OBSERVATION: A 29 month-old child presented with purpura fulminans, probably due to Neisseria meningitidis. Positivity of the serodiagnostic for coxsackie B2, performed because of persisting myocardial deficiency, evoked diagnosis of a coxsackie B2 co-infection. DISCUSSION: Abnormally prolonged myocardial deficiency during purpura fulminans must lead to the search for a congenital, metabolic or infectious cardiomyopathy.

Child, Preschool↗

Differential detection of rhinoviruses and enteroviruses RNA sequences associated with classical immunofluorescence assay detection of respiratory virus antigens in nasopharyngeal swabs from infants with bronchiolitis.

To define the role of enteroviruses and human rhinoviruses as etiological agents in childhood bronchiolitis, clinical aspirates from 84 infants admitted to hospital with symptoms of obstructive bronchiolitis were tested by picornavirus RT-PCR assay, adenovirus PCR assay and classical immunofluorescence antigen detection of common respiratory viral agents. Respiratory syncytial viruses (A&B) were detectable in 45 of 84 (53.6%) nasopharyngeal aspirates from infants with bronchiolitis, whereas coronaviruses, influenza viruses, and parainfluenza viruses were not detectable in the same samples. Adenoviruses were detectable by PCR in 11 of 84 (13.1%) nasopharyngeal swabs. By using a picornavirus RT-PCR assay followed by a differential molecular hybridisation, rhinovirus and enterovirus RNA sequences were detected in 16 of 84 (19%) and in 10 of 84 (11.9%) of the nasopharyngeal swabs tested. Positive human rhinovirus or enterovirus RT-PCR assay, however, was the only evidence of respiratory infection in 8 of 84 (9.5%) and in 7 of 84 (8.33%) of the studied patients. Respiratory syncytial viruses, human rhinoviruses, adenoviruses, and enteroviruses occur in dual infections detected in 18 of 84 (21.4%) respiratory samples tested. The median duration of stay in hospital was not significantly different between the patients demonstrating a single viral infection and those with a dual viral infection (6.22 +/- 2.07 vs. 5. 04 +/- 0.95 days; P > 0.05). In summary, combination of molecular and classical detection assays of common viruses can be used to demonstrate enterovirus and human rhinovirus respiratory infection in childhood bronchiolitis, and provides an improved approach to obtain new insights into concomitant viral respiratory tract infection in infants.

Antigens, Viral↗

Simultaneous detection of 6 human herpesviruses in cerebrospinal fluid and aqueous fluid by a single PCR using stair primers.

A Herpes Consensus allows the simultaneous detection of 6 human herpesviruses: herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), human cytomegalovirus (HCMV), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), and human herpes virus 6 (HHV-6). This technique was used first to examine retrospectively 100 DNA extracts from 95 CSF and 5 aqueous fluids, prepared by treatment by saturated NaCl followed by ethanol precipitation (n = 63) or by simple boiling (n = 37) and stored at -80 degrees C, and secondly to test prospectively 38 CSF samples for which two DNA extracts were prepared with commercially available DNA extraction kits. In all cases, the results were compared with those of an "in-house" PCR. Concordant results between both PCR and the Herpes Consensus techniques were obtained in 61 of 63 DNA extracts prepared by treatment by saturated NaCl (97%) and in only 31 of 37 boiled samples (84%). Both commercially available methods of DNA extraction examined appear to be suitable for Herpes Consensus PCR, although they cannot remove completely PCR inhibitors that must be sought in case of negative results. This preliminary study shows that the Herpes Consensus method should be of value for rapid diagnosis of herpesvirus infections on condition that it is performed on purified DNA extracts.

Aqueous Humor↗

Human polyomavirus JC latency and reactivation status in blood of HIV-1-positive immunocompromised patients with and without progressive multifocal leukoencephalopathy.

BACKGROUND: Human polyomavirus JC (JCV) induces human progressive multifocal leukoencephalopathy (PML) in patients with AIDS. Peripheral blood mononuclear cells (PBMC) of HIV-1-positive immunocompetent and immunocompromised patients can harbour JCV genome, but their precise role in JCV latency or reactivation status before the onset of PML remains hypothetical. OBJECTIVES: To assess JCV latency or reactivation status in PBMC of HIV-1-positive immunocompromised patients without PML. DESIGN: A group of 82 HIV-1-positive immunocompromised patients who did not have PML were compared with 10 patients with AIDS and PML and with 69 HIV-1-positive immunocompetent patients without PML. METHODS: DNA and total RNA were extracted from PBMC. The presence of JCV DNA was demonstrated by a semi-nested polymerase chain reaction (PCR). By using primer pairs specific for an early gene,T, and a late gene, VP1, the expression of both early and late gene mRNA in PBMC could be identified using reverse transcriptase (RT) PCR. RESULTS: JCV DNA was detected by PCR in 17.4% of 69 HIV-1-positive immunocompetent patients, in 23.2% of 82 HIV-1-positive immunocompromised patients, and in 60% of 10 patients with AIDS and PML. No correlation could be drawn between the detection of JCV DNA in the PBMC and the clinical or biological status of the HIV-1-positive patients. By using RT-PCR procedures, no expression of JCV early and late mRNA in PBMC was found in any patients. CONCLUSIONS: JCV DNA is detectable in the PBMC of 20.5% of 151 HIV-1-infected patients independently of the CDC (Centers for Disease Control and Prevention) stages of the infection. Moreover, our results suggest that active replication of JCV in PBMC appears to be absent or at least a very rare event in HIV-1-positive immunocompromised patients with and without PML.

Acquired Immunodeficiency Syndrome↗

A clinical and epidemiological study of human parvovirus B19 infection in fetal hydrops using PCR Southern blot hybridization and chemiluminescence detection.

Ninety-eight samples from 80 cases of spontaneous abortions after fetal death or hydrops fetalis from 12,000 pregnant women were examined using PCR. DNA was extracted from amniotic fluid, fetal blood, ascitic fluid and fetal biopsies or placenta specimens using QIA amp kits (QIAGEN). A 270-bp length fragment located within the B19 gene NS1 was amplified using PCR followed by electrophoresis and southern-blot hybridization assay using a horseradish peroxidase-labelled probe and chemiluminescence detection. This assay was able to detect 1 to 10 DNA copies in a 10 microliters sample. Parvovirus B19 was identified in 11 cases (14% of fetal hydrops; 1 case for 1,100 pregnancies). Amniotic fluid was the most common and reliable sample to assess the diagnosis. Gestational age ranged from 17 to 28 weeks (mean 23 weeks). IgM antibodies were detected in 3 maternal sera, 2 patients of which reported an exposure to B19 infection during pregnancy. In 2 cases, intrauterine blood transfusions led to the cessation of symptoms and to birth of normal babies.

Adolescent↗

Comparison of use of cerebrospinal fluid, serum, and throat swab specimens in diagnosis of enteroviral acute neurological infection by a rapid RNA detection PCR assay.

A PCR assay for detection of enterovirus RNA in multiple specimen types from patients with neurological infections was evaluated. Combined PCR assay of cerebrospinal fluid and serum (systemic specimens) was more sensitive than assaying either specimen alone in children but not in adults. Compared with PCR in systemic specimens, detection of enterovirus RNA in throat swabs showed a sensitivity of 62.5% and a specificity of 75.6%.

Adult↗

[Comparison of the in vitro sensitivity to cidofovir and ganciclovir of clinical cytomegalovirus isolates. Coordinated Action Group 11].

Cidofovir (CDF) or Vistid is a monophosphate nucleoside analogue that inhibits the DNA polymerase of herpes viruses including the cytomegalovirus (CMV). CDF is active on GCV-resistant strains with a mutation on the phosphotransferase gene (UL97). However, DNA polymerase gene mutations that induce resistance to GCV are responsible for cross-resistance to CDF. Resistance phenotypes to GCV and CDF were determined for 57 CMV strains isolated from blood and urine samples. Sixteen strains were recovered after CDF therapy. Of the remaining 41 CDF-naive strains, 34 were susceptible and seven resistant to GCV. Fifty percent inhibitory concentrations (IC50) for CDF were in the 0.2-2.6 microM range for CDF-naive strains susceptible to GCV. For GCV-resistant strains, IC50 values for CDF were < or = 3 microM for strains with a low level of resistance to GCV (GCV IC50 < 30 microM) and > or = 6 microM for three of the five strains with a high level of resistance to GCV (GCV IC50 > or = 30 microM).

Antiviral Agents↗

Inactivation of intracellular and non-enveloped viruses by a non-ionic naphthalene endoperoxide.

Singlet oxygen (1O2, 1delta(g)) selectively oxidizes many biological targets, some of which, such as viruses, are located intracellularly under in vivo conditions. Considering the short lifetime of 1O2 in aqueous media, it is essential to generate this species in close proximity to the targets. Therefore, a water-soluble and non-ionic carrier of 1O2, DHPNO2, has been designed to convey 1O2 through lipid membranes. In contrast to the known anionic carrier NDPO2, which inactivates only extracellular enveloped viruses, the new compound exhibits virucidal activity on all types of viruses, enveloped (HIV) and non-enveloped (Poliovirus), extracellular and intracellular. HIV inactivation can also be achieved in the presence of red blood cells, suggesting the possible use of DHPNO2 in the decontamination of cellular blood products.

Animals↗

Detection of enteroviral RNA by polymerase chain reaction in endomyocardial tissue of patients with chronic cardiac diseases.

Enteroviruses are suspected to be etiologic agents in myocarditis and cardiomyopathy. The prevalence of enteroviral (EV) heart infection in patients with chronic cardiomyopathy was determined through detection of specific EV genomic sequences using reverse transcription and polymerase chain reaction (RT-PCR) followed by slot blotting. Endomyocardial biopsies from the explanted hearts of 19 patients with dilated cardiomyopathy (DCM) and 14 patients with chronic coronary disease (CCD) were examined. EV genome was detected in 11 of 19 patients with DCM and in 8 of 14 patients with CCD. Ventricular biopsies from the control group, which included 35 healthy heart patients and 33 patients with myocardial infarction, were negative by EV RT-PCR. The percentage of patients showing presence of EV-RNA was almost similar in the DCM (57.9%) and CCD (57.1%) groups. The present study demonstrates that enterovirus RNA sequences persist in the myocardium in a significant proportion of patients suffering from end-stage ischaemic and dilated cardiac diseases and supports the hypothesis of a possible direct link between EV infection and the pathogenesis of chronic heart disease.

Adult↗

Relationship between CMV and graft rejection after heart transplantation.

This study, which included 153 heart transplant patients, was designed to determine whether the cytomegalovirus (CMV) status of both donor and recipient may influence graft rejection. The follow-up was 1 year and they all received the same triple-drug immunosuppressive regimen with induction (antilymphocyte serum). There was no difference in the total rejection rate, but an increase in repeated rejection rate was shown in transplant recipients with hearts from CMV seropositive donors (P < 0.05). These data strongly suggest the impact of CMV in enhancement but not in induction of rejection. To prevent iterative rejection in the CMV seropositive donor group, antiviral therapy could be proposed during enhancement of antirejection therapy.

Cytomegalovirus Infections↗

Rapid detection of enterovirus in clinical specimens using PCR and microwell capture hybridization assay.

A rapid detection method of enteroviral RNA in clinical samples using PCR and a microwell capture hybridization assay is described. PCR products were labelled directly by digoxigenin-dUTP during the amplification step. The labelled amplicons were hybridized with a biotinylated oligo-probe and captured on commercially available test microwells coated with streptavidin. The hybridized amplicons labelled with digoxigenin were detected using anti-digoxigenin Fab fragments conjugated to peroxidase and colorimetric reaction automatically measured. This method detected as few as 0.01 PFU/100 microl of biological sample with a result obtained within 8 h. Using this method, we were able to detect enteroviral RNA in 23 of 35 clinical specimens from 16 of 17 patients with suspected acute or chronic enteroviral infection. The samples included cerebrospinal fluid, broncho-pulmonary lavage, pericardial effusion, throat swabs, stools, sera, muscular and myocardial biopsies. In contrast, virus was isolated in cell culture in only 8 of 28 clinical specimens from 6 of the 17 patients. This easy-to-perform assay has useful potential in the rapid detection of enterovirus in acute or chronic infection. This methodology could be used for a rapid qualitative detection of other RNA viruses.

Enterovirus↗

Virucidal activity of pure singlet oxygen generated by thermolysis of a water-soluble naphthalene endoperoxide.

Using the water-soluble naphthalene carrier of singlet oxygen NDPO2, we have shown that pure singlet oxygen is able to inactivate enveloped viruses (human immunodeficiency virus type 1, herpes simplex virus type 1, cytomegalovirus, vesicular stomatitis virus), but has no effect on non-enveloped viruses (adenovirus and poliovirus 1). These results are related to the experiments on photoinactivation of viruses by hydrophobic photosensitizers (merocyanine 540, hypericin, phthalocyanines, hematoporphyrin and benzoporphyrin derivatives) and they strengthen the hypothesis that singlet oxygen plays a predominant role in this process.

Adenoviruses, Human↗

Cell membrane bound N-acetylneuraminic acid is involved in the infection of fibroblasts and phorbol-ester differentiated monocyte-like cells with human cytomegalovirus (HCMV).

We focused on the role of membrane bound sugar residues in the infection of fibroblasts and monocyte-like cells with human cytomegalovirus (HCMV). Treatment of phorbol 12-myristate 13-acetate (PMA) differentiated monocyte-like cells THP-1 or human fibroblasts MRC-5 with lectins specific for N-acetylneuraminic acid (NeuAc) blocked infection with HCMV. HCMV failed to infect sialidase-treated differentiated THP-1 cells or MRC-5 cells. By using NeuAc, N-glycolylneuraminic acid (NeuGl) and alpha 2-3, but not alpha 2-6, sialyl-oligosaccharide, the infection of cells was less efficient. NeuAc was more potent inhibitor than NeuGl. These observations suggest that the sialic acid specificity and the nature of the interglycosidic linkage at the end of the complex carbohydrates may play an important role. Analogous experiments indicated that HCMV binds to N-acetylglucosamine (GlcNAc) in addition to NeuAc. Human cytomegalovirus infection in differentiated THP-1 cells and in human fibroblasts was inhibited by incubation of the virus with 20 micrograms/ml of heparin before and during the adsorption period. Treatment of the cells with heparinase or heparitinase inhibited infection with HCMV. We emphasized the role of NeuAc and GlcNAc and heparan sulfate proteoglycans at the surface of the cells, in the early steps of infection of both human fibroblasts and PMA differentiated monocyte-like cells with HCMV.

Acetylglucosamine↗

[Current status of human cytomegalovirus disease].

Human cytomegalovirus (HCMV) can establish lifelong persistence after primary infection with reactivation occurring as a result of immunosuppression. There is much evidence that molecular interactions between the immune system and the HCMV are responsible for immune escape. HCMV in many cells especially in mononuclear blood cells during latency are frequently the source of transmission and spreading and results in a variety of disorders. In this review some data about acute infection in immunocompetent host (mononucleosis, hepatitis), about intrauterine HCMV infection, about infection and endogenous reinfection in bone marrow and solid organ transplant recipients (pneumonitis) and about HCMV disease in AIDS patients (encephalitis, neuropathy, retinitis, colitis) are investigated. Moreover, HCMV associated vasculitis is described in patients with myocarditis, rheumatoid arthritis or polyradiculopathy. HCMV could play an important role in atherosclerosis. Several types of human malignancy have been linked to HCMV and it has been shown that HCMV ie genes upregulate expression of cellular oncogenes. The diagnosis of HCMV infection is carried out by viremia in cell culture using immediate early antigen staining, by antigenaemia which appears to be an early quantitative and predictive tool, by HCMV DNA detection using hybridization and PCR, and by IgM and IgG antibody evaluation. Two antiviral drugs are used for treatment: ganciclovir and phosphonoformic acid; few resistant clinical isolates have been reported. Specific gammaglobulin activity is discussed. HCMV vaccine is not available.

Adult↗