Jean-Luc Bailly

Impact of rapid enterovirus molecular diagnosis on the management of infants, children, and adults with aseptic meningitis

Enteroviruses (EV) are the main etiological agents of aseptic meningitis. Diagnosis is made by detecting the genome using RT‐PCR. The aim of the study was to evaluate the impact of a positive diagnosis on the management of infants, children, and adults. During 2005, 442 patients were admitted to hospital with suspected meningitis. Clinical and laboratory data and initial treatment were recorded for all patients with enteroviral meningitis. The turnaround time of tests and the length of hospital stay were analyzed. The results showed that EV‐PCR detected EV in 69 patients (16%), 23% (16/69) were adults. About 18% of CSF samples had no pleocytosis. After positive PCR results, 63% of children were discharged immediately (mean 2 hr 30 min) and 95% within 24 hr. Infants and adults were discharged later (after 1.8 and 2 days, respectively). The use of antibiotics was significantly lower in children than in infants and adults. The PCR results allowed discontinuation of antibiotics in 50–60% of all patients treated. Patients received acyclovir in 16% of cases (7% children vs. 50% adults) and 23% (11% vs. 69%) underwent a CT scan. Clinical data were compared between patients whose positive EV‐PCR results were available within 24 hr (n = 32) and those whose results were available > 24 hr after collection of CSF (n = 14). Duration of antibiotic treatment (difference: 2.3 days; P = 0.05) was reduced between the two groups. No statistical difference in the length of stay was observed. The EV‐PCR assay should be performed daily in hospital laboratory practice and considered as part of the initial management of meningitis. J. Med. Virol. 81:42–48, 2009.

Prospective identification of enteroviruses involved in meningitis in 2006 through direct genotyping in cerebrospinal fluid.

ABSTRACT Enterovirus infections were investigated with special emphasis on performing rapid molecular identification of enterovirus serotypes responsible for aseptic meningitis directly in cerebrospinal fluid (CSF). Enterovirus genotyping was carried out directly with specimens tested for the diagnostic procedure, using two seminested PCR assays designed to amplify the complete and partial gene sequences encoding the VP1 and VP4/VP2 capsid proteins, respectively. The method was used for identifying the enterovirus serotypes involved in meningitis in 45 patients admitted in 2005. Enterovirus genotyping was achieved in 98% of the patients studied, and we obtained evidence of 10 of the most frequent serotypes identified earlier by genotyping of virus isolates. The method was applied for the prospective investigation of 54 patients with meningitis admitted consecutively in 2006. The enterovirus serotypes involved were identified with the cerebrospinal fluid (CSF) of 52 patients (96%) and comprised 13 serotypes within the human enterovirus B species and 1 within the human enterovirus A species. The three most common serotypes were echovirus 13 (E13; 24%), E6 (23%), and coxsackievirus B5 (11.5%), a pattern different from that observed in 2005. Genotyping of virus isolates was also performed in 35 patients in 2006 (meningitis, n = 31; other diseases, n = 4). By comparison, direct genotyping in CSF yielded a more complete pattern of enterovirus serotypes, thereby allowing the detection of rare serotypes: three less common serotypes (CB2, E21, and E27) were not detected by indirect genotyping alone. The study shows the feasibility of prospective enterovirus genotyping within 1 week in a laboratory setting.

High Prevalence of Hepatitis C Virus Type 5 in Central France Evidenced by a Prospective Study from 1996 to 2002

ABSTRACT From 1996 to 2002, hepatitis C virus (HCV) typing was prospectively performed for 1,281 unselected HCV-infected and viremic patients, irrespective of their clinical status. Eighty-three patients (6.5%) were coinfected with human immunodeficiency virus (HIV) and HCV. A total of 1,195 strains were identified by a serotype screening (Murex HCV Serotyping 1-6 assay) and/or genotyping (Inno-LiPA HCV II) test. The distribution of HCV types showed an unusually high rate of type 5 (14.2%) that was stable over time and was the third most frequent type, after type 1 (59.1%) and type 3 (15.1%). HCV type 5 was more frequent in patients who were older than 50 (P = 10−6), but its frequency did not differ significantly by gender (P = 0.21). Serotyping was performed for 1,160 strains but failed for 30.2% of them. The efficiency depended on HIV status (for HCV-HIV-coinfected patients, half of the strains were untypeable) and HCV type. Genotyping was performed for 428 samples, with an overall efficiency of 99.3%. It failed in three cases, which were subsequently identified as HCV type 2. Serotyping and genotyping results for 39 patients showed discrepancies between the two methods for 4 patients, who had HCV type 2, type 6, or mixed infections. Thus, HCV type 5 may also be encountered frequently in Western countries. Its apparent confinement to a restricted area raises the question of how it emerged and underscores the need for further studies of HCV type prevalence, routes of transmission, pathogenicity, and responses to treatment.

Phylogeography of circulating populations of human echovirus 30 over 50 years: Nucleotide polymorphism and signature of purifying selection in the VP1 capsid protein gene

A comprehensive set of 443 1D gene sequences (encoding the VP1 capsid protein) was analyzed to investigate the phylogenetic relationships and evolutionary patterns among strains of human echovirus 30 (E30; genus Enterovirus, family Picornaviridae) characterized over 50 years. Maximum-likelihood (ML) phylogenetic trees of complete and nonredundant 1D gene sequences (total length=876 nucleotides) showed evidence of distinct lineages related to the isolation period of virus strains. Virus transportation was confirmed as a major epidemiological factor in the appearance of epidemics since recurrence of aseptic meningitis outbreaks in a given geographic area was associated with distinct E30 variants detected earlier in distant regions. Detection of the codon changes associated with E30 evolution was investigated with methods implemented in the Datamonkey web server. Evolution of the 1D gene was dominated by continual negative (purifying) selection against nonsynonymous substitutions at most codon sites, as determined by dN/dS ratio. Amino acid polymorphism was maintained at a limited number of sites (10/292) in the VP1 protein (within loops connecting beta strands and C-terminus). Amino acid changes are allowed at these sites because they are likely exposed on the virion particle and nonsynonymous substitutions are observed in the corresponding codons because negative selection is relaxed.

Epidemiology of human enterovirus 71 infections in France, 2000-2009

BACKGROUND Human enterovirus 71 (EV-71) emerged as a significant pathogen able to cause large outbreaks involving severe neurological cases and children fatalities in Asia. OBJECTIVES To describe epidemiology of EV-71 infections in France. STUDY DESIGN Fifty-nine patients admitted in 12 different hospitals from 1994 to 2009 were included. The entire VP1 coding gene of 58 EV-71 strains was sequenced and phylogenetic analyses were performed to assign strains to genogroups/subgenogroups and to compare French isolates to European and worldwide isolates. RESULTS The median age of the patients was 1.04 years (9 days to 7 years). Among 46 documented EV-71 infections, 39 were self-limited. Seven children developed severe sepsis-like, respiratory or neurological complications. Among them, 2 children died from acute respiratory distress syndrome. All the EV-71 strains belonged to genogroup C: 31 isolates belonged to subgenogroup C1, 26 to subgenogroup C2 and 1 to subgenogroup C4. All the strains were genetically related to other European strains isolated at the same period of time. Although C1 isolates were predominant between 1994 and 2005, C2 strains have been predominant since 2007. No association was found between any genotype and the age or the clinical symptoms. CONCLUSIONS The C4 subgenogroup, which was associated with large outbreaks in China, did not spread in France. It is important to monitor more carefully the EV-71 strains circulating in France to detect the introduction of new genetic variants that could be associated with major outbreaks.

Prospective analysis of 61 cases of enteroviral meningitis: interest of systematic genome detection in cerebrospinal fluid irrespective of cytologic examination results

BACKGROUND Enteroviruses are the most commonly identified cause of viral meningitis. Detection of the enterovirus genome in cerebrospinal fluid (CSF) using reverse-transcription polymerase chain reaction (PCR) has proved to be useful in diagnosis and is more rapid and sensitive than viral cultures. In routine practice, cytologic examination results of CSF are obtained swiftly and PCR indication is performed as a second step. OBJECTIVES The aim of this study was to determine, by analysis of complete data from CSF results for 61 cases of proven enteroviral meningitis, whether cytologic CSF findings can be used to establish viral etiology and to indicate if PCR assay should be performed. STUDY DESIGN From a prospective study of children admitted during 1997 for suspected enterovirus meningitis in which PCR and viral cultures of CSF were systematically performed, we selected 61 patients with proven enterovirus meningitis. We compared global white cell count (WCC), relative percentage of lymphocytes/neutrophils, PCR and culture for enterovirus, patient age, and clinical data. RESULTS 92% of patients (56/61) had positive PCR in CSF and in 48% (29/61) enterovirus was isolated in CSF. Nine patients (14.75%) had WCC<10/mm(3); eight of them had positive PCR and two had positive culture. There were comparable numbers of CSF with a predominance of lymphocytes (n=25) and CSF with a predominance of neutrophils (n=22), and of positive PCR and positive cultures of CSF in the two groups. Results were not influenced by the age of the patients. CONCLUSION Irrespective of other CSF parameters, it seems difficult to dispense with PCR assay for enterovirus genome detection. It should be introduced as a true rapid routine test. Early reporting of a positive PCR result could result in a considerable saving in health resources.

Molecular Evidence of Persistent Echovirus 13 Meningoencephalitis in a Patient with Relapsed Lymphoma after an Outbreak of Meningitis in 2000

ABSTRACT Enteroviral meningoencephalitis was diagnosed in a patient with an immunodeficiency syndrome acquired after treatment with rituximab for a relapsed primary B-cell lymphoma. A second meningoencephalitic episode was diagnosed 6 months later and was successfully treated with a combination of immunoglobulins and pleconaril. The infection was persistent since the enterovirus genome was detected in five sequential specimens of cerebrospinal fluid collected over 9 months. An echovirus 13 isolate was isolated in the first three samples. The viral sequence encoding the VP1 capsid protein of the three isolates was determined and was compared with that of four control viruses. The virus isolates recovered from the patient shared >99% nucleotide sequence similarity with one another. In a phylogenetic tree, they were directly related to a control virus obtained from a patient hospitalized in 2000 during an outbreak of enterovirus meningitis. The epidemiological origin of a chronic echovirus infection in a patient with immune deficiency suggests that the echovirus had been continuously circulating in the general population after the outbreak that had revealed its emergence.

Fatal adenovirus infection in a neonate and transmission to health-care workers

BACKGROUND Human adenovirus (HAdV) infections, while common in infancy and childhood, occur rarely in the neonatal period but may be fatal. OBJECTIVES To describe a transmission of HAdV from a patient with fatal pneumonia to heath-care workers that could be considered as a model of respiratory virus transmission in a care unit. STUDY DESIGN Case report with virologic studies. RESULTS A 10-day-old neonate developed pneumonia with acute respiratory distress, external pulmonary bleeding and coagulopathy and died 36h after admission of multivisceral failure. An adenovirus was isolated from pulmonary biopsy and detected by PCR in blood and respiratory secretions. Ten days later, three members of medical staff in charge of this infant, who used neither masks nor glasses for close patient contact, developed keratoconjunctivitis. Molecular analysis of the infants and one of the pediatricians isolates identified a species D HAdv and showed 100% identity, thereby demonstrating viral transmission. CONCLUSION In view of the serious outcome, HAdV infections should be considered in the differential diagnosis of pneumonia in neonates. This case illustrates the epidemic potential of viruses with respiratory transmission and underlines the importance of complying with standard precautions to prevent viral spread in routine practice.

Repeated genomic transfers from echovirus 30 to echovirus 6 lineages indicate co-divergence between co-circulating populations of the two human enterovirus serotypes.

Human echovirus types 6 (E-6) and 30 (E-30) cause seasonal epidemics of aseptic meningitis. These two enteroviruses are frequently observed in co-circulation, an epidemiological pattern that is prerequisite for the occurrence of dual infections, which can lead to recombination between co-infecting virus strains. Viral sequences were determined at loci 1D (VP1 capsid protein) and 3CD (non structural proteins) in 49 E-6 strains recovered in a single geographical region in France from 1999 to 2007, during the epidemiological survey of enterovirus infections. They were compared with previously recorded sequences of E-30 strains to investigate their evolutionary histories and possible recombination patterns. Phylogenetic analyses identified two distinct E-6 populations and different subpopulations. Assuming a relaxed molecular clock model and a Bayesian skyline demographic model in coalescent analyses with the BEAST program, the substitution rate in E-6 was estimated at 8.597×10(-3) and 6.252×10(-3) substitution/site/year for loci 1D and 3CD respectively. Consistent estimates of divergence times (t(MRCA)) were obtained for loci 1D and 3CD indicating that two distinct E-6 populations originated in 1997 and 1999. Incongruent phylogenetic patterns inferred for the two loci were indicative of recombination events between the two populations. Phylogenies including the E-30 3CD sequences showed close genetic relationships between E-6 and discrete E-30 subpopulations. Recombination breakpoints were located with statistical significance in E-6 and E-30 genomes. Estimates of t(MRCA) of phylogenetic recombinant clades indicated directional genetic transfers from E-30 to E-6 populations and their co-divergence over the time period studied.

Prospective genotyping of human rhinoviruses in children and adults during the winter of 2009–2010

BACKGROUND About 100 serotypes of human rhinovirus (HRV), classified into two species, have been identified by 1990. Uncultivable HRV variants have recently been identified and designated a new species. Recent improved diagnosis has led to a re-appraisal of the clinical impact of HRV infections in lower respiratory diseases. OBJECTIVES To characterise clinical features in hospitalised patients with positive HRV RNA detection and to determine the distribution of HRV species in respiratory infections diagnosed during the winter of 2009-2010. STUDY DESIGN Prospective virus typing was conducted by sequencing the VP4/VP2 genomic regions, and clinical data were collected. RESULTS Fifty-eight patients (for 63 respiratory specimens) were included. Phylogenetic analysis identified 52% of HRV species A, 6% of species B and 40% of species C, and revealed the co-circulation of 34 different HRV types during the study period. Three infants had successive infections with two or three different types. Five patients were admitted to an intensive care unit, four of them on arrival. Bronchiolitis, pneumonia and exacerbation of asthma were observed in 34/45 children. Pneumonia and severe exacerbation of chronic lung disease were observed in 8/13 adults, of whom 1, with immunocompromised status, died of multivisceral failure. CONCLUSIONS This study underlines the diversity of co-circulating strains and the potential severity of clinical presentations associated with HRV infections.