In vitro antimicrobial susceptibility of Helcococcus kunzii and molecular analysis of macrolide and tetracycline resistance.

Thanks to the recent advent of matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) technology, Helcococcus kunzii is now easily identifiable and considered as an opportunistic pathogen. However, data about antimicrobial susceptibilities remain very limited. The aim of the study was, then, to assess its in vitro susceptibility to 18 antimicrobial agents and to investigate the genetic basis of macrolide and tetracycline resistance. Thirty-nine human clinical isolates of H. kunzii collected from 2008 to 2013 were studied, as well as the type strain ATCC 51366(T). Minimum inhibitory concentrations (MICs) of penicillin G, amoxicillin, cefotaxime, imipenem, gentamicin, erythromycin, clindamycin, quinupristin-dalfopristin, ciprofloxacin, levofloxacin, tetracycline, tigecycline, vancomycin, teicoplanin, linezolid, daptomycin, cotrimoxazole and rifampin were determined by the microdilution method. Screening for macrolide [erm(A) including erm(TR), erm(B), erm(C), erm(F), erm(T), erm(X), msr(A) and mef(A)] and tetracycline [tet(L), tet(M) and tet(O)] resistance genes was performed, as well as the detection of mutations in 23S rRNA. Except for one strain resistant to cefotaxime, all strains were categorised as susceptible to ß-lactams, glycopeptides, linezolid, daptomycin and tigecycline. Whereas ciprofloxacin and gentamicin exhibited limited activity, 95% of strains were categorised as susceptible to levofloxacin. Concerning erythromycin, a bimodal distribution was observed, with 29 'wild-type' strains (MICs from 0.25 to 2 mg/L) and 11 'resistant' strains (MICs ≥ 256 mg/L), including ten harbouring erm(TR). Two isolates exhibited acquired tetracycline resistance (MICs of 16 mg/L) by the production of tet(M). This large study on the in vitro antimicrobial susceptibility of H. kunzii suggests that ß-lactams (especially penicillins) should be preferred for the treatment.

Faecal carriage of oxyiminocephalosporin-resistant Enterobacteriaceae among paediatric units in different hospitals in the south of France.

The aim of this study was to determine the presence of oxyiminocephalosporin-resistant (OCR) Gram-negative bacilli and extended-spectrum ß-lactamase (ESBL)-producing isolates in stool specimens obtained from paediatric patients hospitalised for acute diarrhoea. We conducted a prospective, multicentre study over a period of 6 months in seven hospitals in the south of France. Samplings were carried out from infants admitted for acute diarrhoea with no previous antibiotic treatment in the last week. Bacteria in stool specimens were screened for the presence of OCR Gram-negative bacilli on Drigalski agar supplemented with ceftazidime and ESBL CHROMagar® media, and confirmed by the Rosco tablets test. Genetic detection was performed by the Check MDR® microarray and by polymerase chain reaction (PCR) and sequencing with bacterial DNA extracted from isolates. The presence of OCR enterobacteria was markedly high (177/1,118 patients, 15.2 %), with an important community origin (66.1 %). The majority of multidrug-resistant (MDR) bacteria were Enterobacter cloacae (106, 59.9 %) and Escherichia coli (61, 34.5 %). The prevalence of ESBL and CTX-M producers represented 5.2 and 4.3 % of the isolates, respectively. The main proportion of these ESBL carriers was found in children less than 1 year of age (53.4 %). One carbapenemase (IMP-1) was detected. The study revealed the wide dissemination of MDR bacteria in infants attending hospitals in the south of France during a non-outbreak situation, in particular, the spread of cefotaximase and the detection of a carbapenemase. This worrisome situation must reinforce the use of hygiene procedures and appropriate antibiotics to control the emergence and spread of OCR organisms.

[Recurrent fever and skin eruption revealing chronic meningococcemia]. / Fièvre prolongée associée à une éruption cutanée diffuse révélant une méningococcémie chronique.

INTRODUCTION: Chronic meningococcemia is an unusual clinical presentation within the spectrum of infections due to Neisseria meningitidis. CASE REPORT: We report a 32-year-old man who presented with a 15-day history of fever and maculopapular skin rash, in the absence of meningeal irritation or severe sepsis manifestation. Blood culture identified N. meningitidis. Clinical course was uneventful after antibiotic treatment was initiated. CONCLUSION: Early diagnosis of chronic meningococcemia is crucial for optimal management of the patient and his/her contacts. Such a diagnosis should be suspected in the presence of the characteristic clinical triad (recurrent fever, skin rash and arthralgia), and this clinical presentation should be distinguished from systemic vasculitis as inadequate prescription of corticosteroids may be deleterious.

An outbreak of airborne tularaemia in France, August 2004.

Fifteen tularaemia cases were identified after a holiday spent at a converted mill in the Vendee region in France, between 9 and 12 August 2004. The mill was visited, and descriptive, retrospective cohort and environmental investigations were conducted. The 39 people who had stayed at the mill between 24 July and 11 August were asked about symptoms, exposure to food and animals, and leisure activities. A case was defined as a person with evidence of fever and a positive serology (seroconversion or significant rise in antibody titre, or a single titre) = 40. Culture for Francisella tularensis and polymerase chain reaction (PCR) diagnosis was carried out for drinking water, firewood, and domestic animals at the mill. Fifteen cases of tularaemia (38%) were confirmed. Twelve of the cases (80%) had the pulmonary form. None of the patients was admitted to hospital. There was a strong association between infection and participation in a dinner at the mill on 4 August (p < 10(-8)). One of the three dogs present in the dining room was serologically positive for F. tularensis. Results of analysis of environmental samples were negative. These investigations confirmed the occurrence of a cluster of 15 tularaemia cases, in patients who were infected on the evening of 4 August, in a mill in VendAe, an endemic area for tularaemia. The investigations highlight the existence of nonspecific and benign pulmonary forms of the illness in France. The pulmonary form of infection in the human cases and the positive serology of the dog suggest contamination by inhalation of contaminated particles from the dogos fur disseminated by the dog shaking itself.

An outbreak of airborne tularaemia in France, August 2004.

Fifteen tularaemia cases were identified after a holiday spent at a converted mill in the Vendee region in France, between 9 and 12 August 2004. The mill was visited, and descriptive, retrospective cohort and environmental investigations were conducted. The 39 people who had stayed at the mill between 24 July and 11 August were asked about symptoms, exposure to food and animals, and leisure activities. A case was defined as a person with evidence of fever and a positive serology (seroconversion or significant rise in antibody titre, or a single titre) = 40. Culture for Francisella tularensis and polymerase chain reaction (PCR) diagnosis was carried out for drinking water, firewood, and domestic animals at the mill. Fifteen cases of tularaemia (38%) were confirmed. Twelve of the cases (80%) had the pulmonary form. None of the patients was admitted to hospital. There was a strong association between infection and participation in a dinner at the mill on 4 August (p<10-8). One of the three dogs present in the dining room was serologically positive for F. tularensis. Results of analysis of environmental samples were negative. These investigations confirmed the occurrence of a cluster of 15 tularaemia cases, in patients who were infected on the evening of 4 August, in a mill in Vend¨¦e, an endemic area for tularaemia. The investigations highlight the existence of nonspecific and benign pulmonary forms of the illness in France. The pulmonary form of infection in the human cases and the positive serology of the dog suggest contamination by inhalation of contaminated particles from the dog¡¯s fur disseminated by the dog shaking itself.

[Tularemia. The disease and its epidemiology in France]. / La Tularémie. La maladie et son épidémiologie en France.

OBJECTIVE: This study had for aim to determine whether the epidemiologic features of animal and human tularemia observed in France could explain its re-emergence since 1993. MATERIALS AND METHODS: A retrospective study was made of outbreaks in animals and human cases and contamination. RESULTS: Twenty to sixty animal outbreaks were recorded every year but the number of cases was under-estimated. This indicates an increase in animal cases. Human cases or contaminations were associated with areas where animal cases had been recorded, except for a few cases more difficult to explain. Several factors are implicated: the disease is not known, except by hunters. Tularemia is more often described in hares but the disease may be present in other species. The disease and its forms should be documented for clinicians and biologists for an adequate clinical and bacteriological diagnosis. COMMENTS: Several factors in the epidemiology of the animal diseases have changed since 1993. It is necessary to be increasingly vigilant, for animal cases and human contamination. It is necessary to strengthen medical and veterinary supervision especially since Francisella tularensis may be used for bioterrorism.

Reemergence of gentamicin-susceptible strains of methicillin-resistant Staphylococcus aureus in France: a phylogenetic approach.

The reemergence of gentamicin-susceptible (Gen(s)) methicillin-resistant Staphylococcus aureus (MRSA) isolates in France between 1992 and 1996 was investigated using a phylogenetic approach (multiprimer randomly amplified polymorphic DNA typing). Eighty-six percent (65 of 85) of the French strains were grouped into one phylogenetic cluster within which all but one Gen(s) strain were grouped into a subcluster. Thus, the reemergence of Gen(s) MRSA strains in France was likely due to the spread of one specific clone which belonged to a cluster comprising most French gentamicin-resistant (Gen(r)) strains. This suggests that the Gen(s) clone has emerged from a Gen(r) strain of this cluster.

Variation in Bordetella bronchiseptica lipopolysaccharide during human infection.

We previously reported the case of a human chronic Bordetella bronchiseptica respiratory infection, due to contact with infected rabbits. Lipopolysaccharides of the human isolates, of one rabbit isolate and of isolate from other origins were analyzed with sera from infected mice, rabbit and human. Antigenicity and length of the lipopolysaccharide molecules varied between isolates. We showed a progressive loss of O-chain during infection, associated with an enhanced susceptibility of the isolates to the bactericidal effect of normal serum. This observation suggests the existence of an intracellular niche which selects for strains with distinct lipopolysaccharide types.

[Partial properdin deficiency revealed by a septicemia caused by Neisseria meningitidis]. / Déficit partiel en properdine révélé par une septicémie à Neisseria meningitidis.

Properdin is one of the regulatory proteins of the alternative pathway of the complement system. Human properdin deficiency is an X-linked disorder strongly predisposing to meningococcal disease. Total deficiency (type I), partial deficiency (type II), and deficiency due to a dysfunctional molecule (type III) can be differentiated immunochemically. Four males in a family showed a selective partial deficiency of properdin. These individuals had 10% of normal properdin concentration in plasma, as measured by ELISA, while the other complement components were normal. Two of the properdin-deficient individuals in two generations had meningococcal infections. Two were clinically healthy at the time of investigation. Measurement of plasma levels of properdin has to be performed in the case of Neisseria meningitidis, especially where there is a previous history of severe bacterial infections in the same family as measurement of CH50 activity is ineffective for screening properdin deficiency.

Human Bordetella bronchiseptica infection related to contact with infected animals: persistence of bacteria in host.

Within a period of 2 1/2 years, Bordetella bronchiseptica was isolated four times from a 79-year-old woman with bronchopneumonia. We have demonstrated by pulsed-field gel electrophoresis that this infection was related to contact with infected rabbits. The initial human B. bronchiseptica isolate had a phenotype characteristic of usual B. bronchiseptica clinical isolates; it produced toxin and adhesins, such as adenylate cyclase-hemolysin, filamentous hemagglutinin, and pertactin, and was able to induce lethality in a murine respiratory model. By contrast, although the three successive human isolates produced adhesins, they did not express adenylate cyclase-hemolysin and were unable to induce lethality. This implies that adenylate cyclase-hemolysin is required to induce lethality. We suggest that B. bronchiseptica may persist in the host, with expression of adenylate cyclase-hemolysin being essential for the initiation of infection and expression of adhesins being essential for persistence.