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R Quentin

Publications and source records attributed to R Quentin.

At least 55 records · Page 3Linked to original sources

Urogenital, maternal and neonatal isolates of Haemophilus influenzae: identification of unusually virulent serologically non-typable clone families and evidence for a new Haemophilus species.

A collection of 117 strains of Haemophilus influenzae, including 112 non-typable isolates recovered predominantly in the USA and France from genital, obstetric and neonatal sources, was characterized by the electrophoretic mobilities of 10 metabolic enzymes. Eighty-six distinctive multilocus chromosomal genotypes (electrophoretic types, ETs) were distinguished on the basis of allele profiles at the enzyme loci. Isolates of five allied biotype IV ETs were highly divergent from all other strains and hybridization of chromosomal DNA revealed that they undoubtedly represent a previously unrecognized species of Haemophilus. Isolates representing these ETs were recovered predominantly from obstetric infections and serious neonatal diseases and apparently possess specific tropism for the genital tract. Strains of these five ETs were present in samples from both the USA and France, but only in the USA did they cause bacteraemia and meningitis, an occurrence which probably reflects differences in patient management between the two countries. Although strains assigned to H. influenzae (sensu stricto) were strongly polymorphic in multilocus enzyme genotype, 69% of isolates recovered from patients with meningitis and/or septicaemia were assigned to only two clone families, a result suggesting that some serologically nontypable strains of H. influenzae originating from the genital tract are unusually virulent.

Alleles↗

Identification of a high-virulence clone of type III Streptococcus agalactiae (group B Streptococcus) causing invasive neonatal disease.

Chromosomal genotypes of 128 isolates of six serotypes (Ia, Ib, Ic, II, Ic/II, and III) of Streptococcus agalactiae (group B Streptococcus) recovered predominantly from human infants in the United States were characterized by an analysis of electrophoretically demonstrable allelic profiles at 11 metabolic enzyme loci. Nineteen distinctive electrophoretic types (ETs), representing multilocus clonal genotypes, were identified. Mean genetic diversity per locus among ETs of isolates of the same serotype was, on average, nearly equal to that in all 19 ETs. Cluster analysis of the ETs revealed two primary phylogenetic divisions at a genetic distance of 0.65. A single clone (ET 1) represented by 40 isolates expressing type III antigen formed division I. Division II was composed of 18 ETs in three major lineages diverging from one another at distances greater than 0.35 and included strains of all six antigenic classes. The type III organisms in division I produce more extracellular neuraminidase and apparently are more virulent than the type III strains in division II, which are related to strains of other serotypes that cause disease much less frequently. The existence of this unusually virulent clone accounts, in major part, for the high morbidity and mortality associated with infection by type III organisms.

Genotype↗

Typing of urogenital, maternal, and neonatal isolates of Haemophilus influenzae and Haemophilus parainfluenzae in correlation with clinical source of isolation and evidence for a genital specificity of H. influenzae biotype IV.

Over a period of 6 years, 114 strains of Haemophilus influenzae and Haemophilus parainfluenzae were isolated from genital, mother-infant, or neonatal infections. Their serotypes, biotypes, antibiotic resistance phenotypes, and outer membrane protein (OMP) electrophoretic patterns were characterized and correlated with the various clinical outcomes. Genital H. influenzae and H. parainfluenzae appeared to behave mostly as opportunistic pathogens; for instance, 62% of the cases of endometritis or pelvic inflammatory disease were related to the presence of an intrauterine device. However, as seen clearly in one case, the strains may be sexually transmitted. The analysis of OMP patterns proved to be a very convenient method to seek evidence for the sexual origin of the infection. H. influenzae was more often involved in complicated genital infections than was H. parainfluenzae. Nontypeable and biotype II H. influenzae strains were the more frequent isolates, except in pelvic inflammatory diseases, in which biotype I prevailed, and in mother-infant infections, in which one-fourth of the cases were due to biotype IV. Characterization of H. influenzae isolates did not support a general concept of specific genital strains. However, strains of biotype IV clearly stood out with two characteristics: (i) a peritrichous fimbriation and (ii) a very peculiar homogeneous OMP pattern comprising an OMP of molecular weight approximately 18,000 unique to this biotype. These characteristics were also found in H. influenzae biotype IV strains isolated from genital infections in the United States and used as controls. H. influenzae biotype IV strains may thus correspond to a group somewhat adapted to the genital tract.

Female↗

In vitro activities of five new quinolones against 88 genital and neonatal Haemophilus isolates.

In vitro activities of five new quinolones against 88 strains of Haemophilus influenzae and H. parainfluenzae isolated from genitourinary or neonatal infections were studied. All strains were susceptible, and MICs were similar to those for respiratory tract isolates. However, H. influenzae biotype IV appeared to be more susceptible to norfloxacin, enoxacin, and ciprofloxacin than the other biotypes were.

Anti-Bacterial Agents↗

[Maternal-fetal Haemophilus influenzae infections].

In a systematic screening programme for neonatal infections involving 16,008 births, Haemophilus influenzae was isolated in 14 mother-infant couples (0.8 to 1,000 births). Comparisons with other series published in the U.S.A. showed similar circumstances of occurrence and initial clinical manifestations. However, the course of the infection was different, since there was no septicaemia or meningitis in our series. This raises the question of whether the strains responsible for the disease in the U.S.A. have a particular aggressiveness that is unidentifiable by serotype or biotype. In view of the post-partum occurrence of pelvic infections after isolation of H. influenzae during high risk deliveries, asymptomatic parturient women should be treated prophylactically. The 14 strains of H. influenzae isolated, most of them non capsulated and 2/3 of them of biotype IV, probably were of genital origin, although there was no evidence of cervico-vaginal infection. These results are consistent with the concept of genitotropic H. influenzae.

Female↗

[Gastrointestinal infections in children. A strategy for searching pathogenic agents].

From a bacteriological and virological study of 2056 stool samples obtained from 1595 children we have attempted to derive epidemiological arguments leading to an algorithm of coprodiagnosis. We believe that Rotavirus should be systematically searched for at any age, as it is the most frequent pathogen encountered (27% of children with positive detection). If the test is positive, no other test needs to be performed in patients staying less than 4 days in hospital. If the test is negative, or if the child's clinical condition requires prolonged hospitalization, conventional bacteriology must be carried out, including a search for Salmonella, Shigella and Yersinia. The search for Campylobacter should be limited to infections occurring in children under five.

Adolescent↗

[Development of the sensitivity to antibiotics in strains of Neisseria gonorrhea isolated in Touraine over a 5-year period].

347 Neisseria gonorrhoeae strains isolated in Touraine, France, from December 1978 to March 1984 were tested for susceptibility to seven antibiotics using an agar dilution method. Percentage of strains with a penicillin G MIC = 0.06 micrograms/ml rose from 58% in 78-80 to 69% in 82-84. Consistent amoxicillin MICs were found throughout the survey (MIC 50: 0.125 and MIC 90: 0.5 micrograms/ml). Three penicillinase-producing strains were recovered from patients contaminated outside the study area. For tetracycline, minocycline, chloramphenicol and spectinomycin, variations of MICs 50 and 90 did not exceed one dilution either way. For spiramycin, MICs 50 and 90 fell from 2 and 8 micrograms/ml respectively in 78-80 to 1 and 2 micrograms/ml in 82-84. Our findings show that susceptibility of Gonococci to the main antibiotics used for treating gonococcal infections in our area has not changed significantly over the last five years. Moreover, implantation and diffusion of penicillinase-producing strains has failed to occur.

Anti-Bacterial Agents↗

[Acute gonococcal salpingitis].

The authors describe their experience in handling cases of acute salpingitis in a retrospective study that lasted six years. The protocol of investigation in particular consisted in routine laparoscopy and a complete bacteriological investigation. 266 patients had laparoscopy on suspicion of salpingitis and the diagnosis was confirmed in 199 cases (64.8%). Out of the 134 patients who were fully explored bacteriologically and kept in the study the principal group consisted of cases of gonococcal salpingitis (41.8%), whereas 29.8% of the cases had infection with opportunistic pathogens and 28.3% were of doubtful aetiology or where no bacteria were discovered. The figures for recovery of gonococcal bacteria were constant throughout the six years of the study. Gonococcal salpingitis occurred more often in younger women (the mean age was 24.4 years). The signs that were statistically most frequent were: discharge, metrorrhagia and a raised sedimentation rate. The differences that concerned the epidemiology of the cases as well as the clinical and bacteriological data as given in our series and in the literature are presented and discussed.

Adolescent↗

[Haemophilus influenzae orchitis in an adult].

This article reports the case of an adult suffering from orchitis due to Haemophilus influenzae. The difficulties encountered in isolating this bacteria when the correct techniques are not used may explain the apparent rarity of Haemophilus influenzae infections of the genital tract. The physiopathological mechanisms of this infection are discussed in relation to the characteristics of the strain isolated.

Adult↗

[Haemophilus influenza infections in infants and mothers. Three cases (author's transl)].

The three cases reported were diagnosed at the time of contamination by direct examination and culture, at birth, of placental tissue, gastric fluid and peripheral specimens. The culture media included a chocolate agar medium favourable to the growth of H. influenzae. One of the isolates was beta-lactamase producer and therefore resistant to the group A penicillins usually prescribed. Determination of the M.I.C.s of eight antibiotics showed that cefotaxime constitutes, for the time being, a suitable alternative to penicillins against such strains. Early detection of H. influenzae perinatal infections make it possible to treat neonates before complications develop. Among the 19 cases published, there were 4 cases of meningitis, 8 cases of septicaemia and 1 case of arthritis.

Adult↗