Claudine Buffet-Janvresse

Epidemiology of Acute Viral Gastroenteritis in Children Hospitalized in Rouen, France

This study assessed the epidemiologic characteristics of acute viral gastroenteritis in hospitalized children. A stool sample obtained from each child was analyzed for the presence of astrovirus, calicivirus, rotavirus, adenovirus, enterovirus, and digestive bacteria. Of the 438 stool samples obtained, 138 tested positive for > or =1 pathogen during the winters of 1997-1998 and 1998-1999 (P<.001). Virologic tests revealed rotavirus in 17.3% of samples, calicivirus in 7.3%, astrovirus in 6.8%, adenovirus in 0.7%, and > or =1 virus in 5.4%. Median age was higher for patients with rotavirus gastroenteritis than it was for those with astrovirus or calicivirus gastroenteritis (P=.014). Mean duration of hospitalization was statistically significantly lower for children with rotavirus gastroenteritis (P=.022), despite the more-frequent dehydration observed among children with rotavirus versus those with astrovirus or calicivirus gastroenteritis (P=.007). In contrast, enteral rehydration was more rapidly achieved in patients with gastroenteritis due to rotavirus.

Genotypic and Phenotypic Resistance Patterns of Human Immunodeficiency Virus Type 1 Variants with Insertions or Deletions in the Reverse Transcriptase (RT): Multicenter Study of Patients Treated with RT Inhibitors

ABSTRACT Genomic rearrangements in the 5′ part of the human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) have been involved in multidrug resistance to nucleoside RT inhibitors (NRTI). We carried out a retrospective, multicenter study to investigate the prevalence, variability, and phenotypic consequences of such rearrangements. Data concerning the HIV-1 RT genotype and the biological and clinical characteristics of NRTI-treated patients were collected from 10 virology laboratories. Sensitivities of the different HIV-1 variants to RT inhibitors were analyzed in a single-cycle recombinant virus assay. Fifty-two of 2,152 (2.4%) RT sequences had a rearrangement in the 5′ part of the RT, with an extensive molecular variation. The number of codons inserted between positions 68 and 69 ranged from 1 (3 samples) or 2 (41 samples) to 5 and 11 in one case each. In four cases, codon 67 was deleted. High levels of phenotypic resistance to zidovudine (AZT), lamivudine (3TC), stavudine (d4T), abacavir (ABC), and didanosine (ddI) were found in 95, 92, 72, 62, and 15% of the 40 samples analyzed, respectively. Resistance to AZT, d4T, and ABC could be found in the absence of the T215Y/F mutations. Resistance to 3TC could develop in the absence of specific mutations. Low-level resistance to ddI was noticed in 40% of the patients. The deletions of codon 67 seemed to have little effect on NRTI sensitivity. Most of the rearrangements were shown to contribute to cross-resistance to NRTI. The results regarding susceptibility to ddI raise the question of the interpretation of the phenotypic data concerning this drug.

Prevalence of resistance mutations in antiretroviral-naive chronically Hiv-infected patients in 1998: a French nationwide study

ObjectiveTo estimate the prevalence of resistance-conferring mutations to antiretroviral drugs in previously untreated patients with chronic HIV-1 infection as a basis for French recommendations on viral genotyping before antiretroviral treatment initiation. DesignResistance mutations were sought in samples from 404 patients seen in 23 specialized centres throughout metropolitan France in 1998. MethodsThe protease and reverse transcriptase (RT) genes of plasma virions were sequenced. Primary and secondary protease and RT gene mutations were identified from the International AIDS Society resistance testing – USA panel. ResultsThe prevalence of patients with primary and secondary mutations were 3.7% (95% CI 1.7–5.7) and 50.3% (95% CI 45.0–55.6), respectively. The prevalence of patients with mutations associated with resistance to nucleoside RT inhibitors (NRTI) and non-nucleoside RT inhibitors was 3.3% (95% CI 1.5–5.1) and 0.8% (95% CI 0.0–1.7), respectively. The prevalence of patients with NRTI primary mutations differed according to whether seropositivity had been diagnosed more or less than one year previously (0.2 versus 2.2%P = 0.023). Primary mutations associated with protease inhibitor resistance occurred at a prevalence of 1.9% (95% CI 0.5–3.4) with no difference according to the duration of known seropositivity. ConclusionIn France, in 1998, the prevalence of patients with primary mutations associated with resistance to antiretroviral drugs was low. Genotyping before the initiation of therapy was not recommended in chronically HIV-1-infected naive patients. A national sentinel survey of resistance in this clinical setting is performed regularly to update the recommendations for resistance testing.

Detection and genotyping of the hepatitis C RNA in tear fluid from patients with chronic hepatitis C

Tear fluid from 51 patients with chronic hepatitis C virus (HCV) infection was analyzed for the presence of the hepatitis C RNA to assess the potential role of this fluid in virus transmission. HCV sequences were amplified from sera and tear fluids by nested polymerase chain reaction using primers from the 5′ non coding region of the virus genome. Positive samples were genotyped by the LiPATM procedure. HCV RNA was detected in 76.5% (39/51) of the sera and in 9.8% (5/51) of the tear fluid samples. The presence of the RNA in the tear fluid was independent of the severity of the hepatitis and of the viral load as measured by the branched DNATM assay. The genotypes of the tears and serum isolates were different for two patients. For another patient, the HCV RNA was positive in the tear sample but negative in the serum sample. These findings suggest that tear fluid may transmit HCV but the source of HCV RNA in this fluid needs to be better understood. J. Med. Virol. 51:231–233, 1997.

Expertise of French Laboratories in Detection, Genotyping, and Quantification of Hepatitis C Virus RNA in Serum

ABSTRACT Before initiating new large-scale therapeutic trials for hepatitis C virus (HCV)-infected patients, the French Health Authorities for HCV research decided to organize an evaluation of the expertise of laboratories that could be engaged to undertake molecular biology assays in such trials; 21 experienced laboratories participated in this national evaluation of laboratory expertise, which was performed in two successive rounds. The first round evaluated the laboratories for their abilities to detect HCV RNA in serum, determine genotypes, and quantify HCV RNA loads. The results observed by qualitative assays for HCV RNA detection were 100% sensitivity and 100% specificity for all laboratories. The genotyping results were 100% concordant for 9 laboratories and greater than 90% for 10 laboratories. By contrast, large coefficients of variation were observed for quantitative determination of HCV RNA loads, leading to a second round with standardized quantitative assays only. The dispersion of the results was larger by the AMPLICOR HCV Monitor assay than by the branched-DNA assay (mean coefficients of variation, 57.4 and 16.9%, respectively). In the majority of cases, discrepancies between the results of the two tests were found for samples with high viral loads. These results indicate the usefulness of validating, by controlling for expertise, both the reliabilities of laboratories involved in multicenter work and the standardized assays chosen for use in the evaluation of the biological impacts of new therapies.

Salivary transmission in an intrafamilial cluster of hepatitis B.

The major modes of transmission of hepatitis B virus are sexual contact, parenteral drug use, transfusion, and vertical transmission. Horizontal transmission has been demonstrated, but its mechanisms remain poorly understood. We report intrafamilial infection in which two siblings were infected by horizontal transmission, probably from ingestion of contaminated saliva. Acute hepatitis B virus (HBV) infection was diagnosed in a child, a father, and two mothers from an African family that included 17 children, all living together in France. Family serologies revealed that a second child had subclinical acute HBV infection, nine siblings were chronic HBV carriers, and five other siblings had infections that resolved spontaneously. The last child, a 1-month-old neonate, was healthy and had been immunized at birth. Horizontal transmission of (HBV) was suspected in the two children with acute disease; no other mode of contamination was suspected. These children were too old to have been contaminated from direct mother-tochild transmission and had not been transfused. They had no percutaneous skin wounds and had not recently traveled. Their infection was probably explained by this African family’s habit of eating meals with their fingers from the same bowl. Means of transmission could not be determined for the other siblings because their period of acute infection was unknown. This case demonstrates intrafamilial HBV contamination and supports the hypothesis that this virus can be transmitted by human saliva.

Infection à virus respiratoire syncytial. Amplification génomique, immunofluorescence et culture

Summary Respiratory syncytial virus (RSV) is the most common cause of respiratory illness during human infancy, particularly among infants under 6 months of age. At the laboratory of Virology at the CHR-Rouen we have developed a method of viral detection based on reverse transcription (RT) and amplification of viral nucleic acid sequences by the polymerase chain reaction (PCR). This procedure was used to screen for RSV in nasopharyngeal aspirates from children with suspected respiratory infections between January and May 1993. Sixty patients under one year of age were included in the study. The PCR approach was compared to classic methods of diagnosis : the results were in good agreement. PCR also identified whether the virus was type A or B. But PCR is laborious, difficult and very expensive. It is still better suited to research than diagnosis.