Epidemiological investigation of Pseudomonas aeruginosa isolates including Multidrug-Resistant serogroup O12 isolates, by use of a rapid and simplified Multiple-Locus Variable-Number of Tandem Repeats Analysis and Whole Genome Sequencing

BACKGROUND

Clustered cases of Pseudomonas aeruginosa infection in immunocompromised patients' wards require rapid characterization of a potential epidemic to guide investigations and identify the potential source of contamination.

AIM

To design and evaluate a rapid and simple typing method for P. aeruginosa in comparison to whole genome sequencing (WGS).

METHODS

We designed and used a simplified PCR based on multiple locus tandem variable number analysis (MLVA) to investigate cases of P. aeruginosa infection and colonization in a paediatric haematology department. The method was compared to WGS by using Illumina method.

FINDINGS

On the 17 isolates recovered from 15 children (8 from blood cultures, 3 from urinary tract infections, 1 from sputum and 5 stool isolates) MLVA distinguished 10 different profiles and 7 isolates from 6 children shared the same profile. Analysis by WGS revealed that these 7 isolates belonged to sequence type ST111 and serotype O12 and permitted to further distinguish at least 3 different genotypes among them. Five environmental strains had 3 MLVA profiles, one shared with a clinical isolate but WGS excluded any relationship.

CONCLUSION

The simplified and inexpensive MLVA method permitted to exclude, in less than five hours, most of unrelated isolates and to focus investigations on a small number of cases while WGS, taking several days of work, drew definitive conclusions concerning the outbreak and the genetic relationships of the ST111 isolates circulating in the department. We conclude that sequential use of both methods is the optimal strategy to investigate grouped cases of P. aeruginosa infections.

Shiga toxin-producing Escherichia coli strains isolated from dairy products - Genetic diversity and virulence gene profiles

Shiga toxin-producing Escherichia coli (STEC) are widely recognized as pathogens causing food borne disease. Here we evaluate the genetic diversity of 197 strains, mainly STEC, from serotypes O157:H7, O26:H11, O103:H2, O111:H8 and O145:28 and compared strains recovered in dairy products against strains from human, meat and environment cases. For this purpose, we characterized a set of reference-collection STEC isolates from dairy products by PFGE DNA fingerprinting and a subset of these by virulence-gene profiling. PFGE profiles of restricted STEC total DNA showed high genomic variability (0.9976 on Simpson's discriminatory index), enabling all dairy isolates to be differentiated. High-throughput real-time PCR screening of STEC virulence genes were applied on the O157:H7 and O26:H11 STEC isolates from dairy products and human cases. The virulence gene profiles of dairy and human STEC strains were similar. Nevertheless, frequency-wise, stx1 was more prevalent among dairy O26:H11 isolates than in human cases ones (87% vs. 44%) while stx2 was more prevalent among O26:H11 human isolates (23% vs. 81%). For O157:H7 isolates, stx1 (0% vs. 39%), nleF (40% vs 94%) and Z6065 (40% vs 100%) were more prevalent among human than dairy strains. Our data point to differences between human and dairy strains but these differences were not sufficient to associate PFGE and virulence gene profiles to a putative lower pathogenicity of dairy strains based on their lower incidence in disease. Further comparison of whole-genome expression and virulence gene profiles should be investigated in cheese and intestinal tract samples.

Haemolytic-uraemic syndrome with bacteraemia caused by a new hybrid Escherichia coli pathotype

We describe a new atypical Shiga-toxin-producing Escherichia coli (STEC) responsible for a severe episode of haemolytic–uraemic syndrome in an adult with a relapse associated with bacteraemia. This STECs train of serotype O80:H2 harboured stx2c and stx2d gene subtypes, the rare eae ξ variant and a ColV plasmid with a conserved virulence plasmidic region involved in virulence of human and avian extraintestinal pathogenic E. coli. This atypical hybrid pathotype, which represents a new threat, is a further demonstration that STEC may be a recipient for extraintestinal virulence factors and raises again the question of antibiotic therapy during STEC infection.

Shopper cards data and storage practices for the investigation of an outbreak of Shiga-toxin producing Escherichia coli O157 infections

INTRODUCTION

An outbreak of shiga-toxin producing Escherichia coli infections occurred in southwest France in June 2012. The outbreak was investigated to identify the source of infection, and guide control measures.

METHODS

Confirmed outbreak cases were patients who developed bloody diarrhoea or haemolytic uremic syndrome (HUS) between 28 May and 6 July 2012, with E. coli O157 isolates showing indistinguishable patterns on pulse field gel electrophoresis (PFGE). A standardized questionnaire was administered to patients to document food consumption and other risk exposures. Their purchase was checked through their supermarket shopper card data.

RESULTS

Six patients (four with HUS and two with bloody diarrhea) were confirmed outbreak cases. Fresh ground beef burgers from one supermarket were the only common food exposure, identified by interviews and shopper card data. The PFGE profile of shiga toxin-producing E. coli O157 isolated from the suspected beef burgers was identical to those from the human cases. The suspected beef burgers were no longer on sale at the time of investigation but three patients confirmed as outbreak cases had deep-frozen some at home.

CONCLUSION

Shopper card data was particularly useful to obtain precise and reliable information on the traceability of consumed food. Despite the expired use-by date, a recall was issued for the beef burgers. This contributed to preventing other cases among consumers who had deep-frozen the beef burgers.

[Escherichia coli 0104:H4: a hybrid pathogen]

In 2011, an outbreak linked to a entero-haemorrhagic Escherichia coli strain, affecting adults more frequently, occurred in Germany, with 4320 bloody diarrhea cases, 850 cases of hemolytic uremic syndrome (HUS) and 82 deaths. Meanwhile, an epidemic affecting 24 patients took place in Bègle with similar epidemiological characteristics. These two strains were associated with consumption of contaminated seeds fenugreck by a particularly virulent strain belonging to a rare serotype, E. coli serotype O104:H4. This strain is a triple hybrid : it produces a shigatoxin, the adhesion at the gastrointestinal mucosa is related to the presence of fimbriae as enteroaggregants E. coli (ECAA), and has virulence factors of E. coli outer intestinal (EXPEC). In addition, it produced a ß-lactamasetype extended-spectrum CTXM15.

A new highly discriminatory multiplex capillary-based MLVA assay as a tool for the epidemiological survey of Pseudomonas aeruginosa in cystic fibrosis patients

Multiple locus variable number of tandem repeats (VNTR) analysis (MLVA) has been shown to provide a high level of information for epidemiological investigations and the follow-up of Pseudomonas aeruginosa chronic infection. In the present study, an automatized MLVA assay has been developed for the analysis of 16 VNTRs in two multiplex polymerase chain reactions (PCRs), followed by capillary electrophoresis. The result in the form of a code is directly usable for clustering analyses. This MLVA-16(Orsay) scheme was applied to the genotyping of 83 isolates from eight cystic fibrosis patients, demonstrating that the same genotype persisted during eight years of chronic infection in the majority of cases. Comparison with pulsed-field gel electrophoresis (PFGE) analysis showed that both methods were congruent, MLVA providing, in some cases, additional informativity. The evolution of strains during long-term infection was revealed by the presence of VNTR variants.

Household transmission of haemolytic uraemic syndrome associated with Escherichia coli O104:H4, south-western France, June 2011

Following the outbreak of haemolytic uraemic syndrome (HUS) on June 2011 in south-western France, household transmission due to Escherichia coli O104:H4 was suspected for two cases who developed symptoms 9 and 10 days after onset of symptoms of the index case. The analysis of exposures and of the incubation period is in favour of a secondary transmission within the family. Recommendations should be reinforced to prevent person-to-person transmission within households.

Household transmission of haemolytic uraemic syndrome associated with Escherichia coli O104:H4, south-western France, June 2011

Following the outbreak of haemolytic uraemic syndrome (HUS) on June 2011 in south-western France, household transmission due to Escherichia coli O104:H4 was suspected for two cases who developed symptoms 9 and 10 days after onset of symptoms of the index case. The analysis of exposures and of the incubation period is in favour of a secondary transmission within the family. Recommendations should be reinforced to prevent person-to-person transmission within households.

Outbreak of haemolytic uraemic syndrome and bloody diarrhoea due to Escherichia coli O104:H4, south-west France, June 2011

Binary file ES_Abstracts_Final_ECDC.txt matches

Community-wide outbreak of Escherichia coli O157:H7 associated with consumption of frozen beef burgers

On 24-25 October 2005 a cluster of five haemolytic uraemic syndrome (HUS) cases was reported in southwest France. An investigation was undertaken to identify the outbreak source and implement control measures. Cases were defined as individuals with HUS or diarrhoea with isolation of Escherichia coli O157:H7 in stools or a positive antibody response to E. coli O157 lipopolysaccharide, resident in southwest France with symptom onset after 19 September 2005. Sixty-nine identified patients had symptom onset between 5 October and 3 November 2005, including 17 cases of HUS. One brand of frozen beef burgers produced on 22 August 2005 was consumed by all patients in the week before symptom onset. E. coli O157:H7 strains from patients, patients' burgers and the manufacturing plant were genetically related. This is the largest community-wide outbreak of E. coli O157:H7 in France to date and the first associated with consumption of contaminated frozen beef burgers.

[Epidemiology of acute otitis media caused by Streptococcus pneumoniae: emergence of serotype 19A]

In this study, the authors report the distribution of serogroups/serotypes and their susceptibility profiles of Streptococcus pneumoniae causing recurrent and difficulties to treat acute otitis media (AOM) in children obtained at the ENT outpatient clinic of Robert Debré Hospital in Paris, between 2002-2008 after the implementation of the 7-valent pneumococcal conjugate vaccine. In this retrospective study, 126 S. pneumoniae isolates were obtained by tympanocentesis from 126 children with AOM during three different periods: 2002-2003 (period 1), 2004-2005 (period 2), and 2006-2008 (period 3). In period 1, the most common serotype was 19F. Between period 1 and period 3, the proportion of serotype 19F decreased from 39 to 13% (P=0.03). In contrast, the proportion of serotype 19A increased from 25 to 60% (P=0.03). So, they observed that vaccine-related serotype 19A became dominant among young children with AOM in 2006-2008. Overall, 15.1% of the isolates were penicillin susceptible, 73.8% intermediate and 11.1% were resistant. Most (94%) of the S. pneumoniae serotype 19A were penicillin intermediate.

[Monitoring serum vancomycin concentrations in the treatment of Staphylococcus infections in children]

INTRODUCTION

Vancomycin is the cornerstone of therapy against methicillin-resistant Staphylococcus in both community- and hospital-acquired infections. Monitoring vancomycin concentration is essential to prevent over- or underdosing of pediatric patients. However, only initial trough vancomycin concentrations may be needed to optimize dosages. The optimal rate of the trough serum level to the minimal inhibitory concentration (MIC) should be equal to or greater than 8 in severe infections.

OBJECTIVES

The aim of this study was to analyze the initial trough serum levels of vancomycin obtained from pediatric patients treated with vancomycin for suspected or confirmed Staphylococcus infections in combination with MIC determination.

PATIENTS

We reviewed the medical records of 3759 children aged, more than 1 month, and 358 neonate patients during a period of 10 years in Robert-Debré Hospital, Paris.

METHODS

Serum levels were determined using the polarization fluorescence method. MIC was determined using the E-test method.

RESULTS AND CONCLUSION

Of the 3759 children studied, 55% had a through serum level less than 10mg/L and 24% had greater than 15 mg/L. Of the 358 neonates, 43% had a trough serum level less than 10mg/L and 31% greater than 15 mg/L. Among these children, 425 had documented Staphylococcus bacteremia with vancomycin MIC determination. Determining the trough level concentration in infected pediatric patients remains mandatory to optimize the vancomycin regimen. The rate of the trough serum level to MIC was less than 4 in 50% of the patients and more than 10 in 5% of the patients.

[Rotavirus infections in a paediatric hospital during 5 years]

Rotavirus is the major cause of gastroenteritis in children and the main cause of hospital acquired-infection in paediatric unit. We report the epidemiology of gastroenteritis in our hospital during five consecutive years. Rotavirus was involved in 13% of the patients. Seasonal peaks were observed in January and 45.8% of the patients were less than 6 month old. The rotavirus infection was hospital-acquired in 1/3 of the cases. During the winter period, the incidence of rotavirus nosocomial infection was 4.4%.

Phylogenetic groups and virulence factors of Escherichia coli strains causing pyelonephritis in children with and without urinary tract abnormalities

Escherichia coli isolates causing acute pyelonephritis in 93 children (25% with urinary tract abnormalities) were tested for nine virulence factors (papC, papGII, papGIII, sfa/foc, hlyC, cnf1, iucC, fyuA and iroN) and their phylogenetic groups were determined. Isolates lacking papGII were more frequent among patients with urinary tract abnormalities (58% vs. 10%, p 0.0003), as were non-virulent phylogenetic group A isolates (25% vs. 5%, p 0.043). Pyelonephritis caused by less virulent E. coli strains was more frequent among patients with significant urinary tract abnormalities. Further studies are required to determine whether screening for E. coli virulence factors may help to identify children warranting anatomical investigations.

[Pseudomonas aeruginosa: resistance to antibiotics]

Pseudomonas aeruginosa antibiotic resistance mechanisms are both innate and acquired, different according to the considered antibiotic; epidemiological follow-up of AB resistance for this pathogen is managed through ONERBA network (www.onerba.org); therapeutic approaches must limit resistant strains diffusion and resistant mutants emergence.

[Two cases of Pseudomonas aeruginosa neonatal meningitis treated by ciprofloxacine]

Two cases of Pseudomonas aeruginosa neonatal meningitis are reported. Case 1 occurred on day 6 of life, at home, in a full term newborn. Favourable outcome was obtained with a treatment associating ceftazidime, 21 days, gentamicin, 10 days and ciprofloxacin, 10 days. Case no 2 was a nosocomial meningitis in a 32 weeks and 4 days gestational age premature newborn. Despite in vitro effective antibiotherapy with ceftazidime, netilmicine and ciprofloxacine, six cerebral abscesses were observed during the second week of treatment. Ceftazidime was stopped after 6 weeks and ciprofloxacine prolonged until neuroradiological cure of cerebral lesions at one year of age. Normal outcome was observed at 3 and 4 and half year of age. Therapeutic indications and clinical tolerance of ciprofloxacine in neonatal meningitis are discussed.

Escherichia coli O157 outbreak associated with fresh unpasteurized goats' cheese

A family cluster of three cases of Escherichia coli O157 infection was identified in France. Two cases developed haemolytic-uraemic syndrome. The source was fresh unpasteurized goats' cheese, produced by an independent producer. Three E. coli O157 strains, isolated from one HUS case and faeces of one cow and one goat, were indistinguishable by toxin type and PFGE pattern.

Ethmoïdites aiguës extériorisées de l'enfant : à propos d'une série de 125 cas

Acute ethmoiditis are bacterial infections of ethmoid sinuses, which may spread to the orbital or the endocranial spaces. It is essential to fit the antibiotherapy to the bacteria responsible for these infections.

POPULATION AND METHODS

The charts of children hospitalized from 1995 to 2003 for an acute ethmoiditis were reviewed, particularly the results of bacterial exams and the antibiotics delivered.

RESULTS

Over this 9-year period, 125 children (mean age 4.5 years) were hospitalized for acute ethmoiditis. Eighty were checked for blood cultures, which were sterile in 73 cases, and in the other cases, grew Staphylococcus, S. Pneumoniae or Streptococcus pyogenes. Seric soluble antigens were absent in the 5 cases where they were looked for. Ten children had a puncture of a subperiostal abscess: it was sterile in 5 cases, Staphylococcus was found in 4 cases, S. pneumoniae in the last case. Most children received an association of cefotaxim and fosfomycine for a mean duration of 5.6 days. Thirteen per cent of the children received 3 or 4 antibiotics.

DISCUSSION

It is always difficult to found the bacteria responsible for an acute ethmoiditis. In our serie as in others, the most frequent bacteria were Staphylococcus, S. pneumoniae and S. pyogenes.

CONCLUSION

In view of the bacteria responsible for these infections and their antibiotic resistance, we suggest the association of cefotaxim and fosfomycin for the first line of treatment of acute ethmoiditis.

Ureaplasma urealyticum, Mycoplasma hominis et pathologiesnéonatales : Données personnelles et revue de la littérature

Ureaplasma urealyticum and Mycoplasma hominis colonized 20-40% of newborns and are more frequent in premature. They are responsible for localized infections such as pleural effusion, pneumopathy, adenopathy, abscess or systemic sepsis. An important hyperleukocytosis is often associated with pulmonary infections. Their responsibility, as pathogen agents, is questionable in some non bacterial meningitis. There is large controversy for their role as cofactor, in chronic lung disease (bronchopulmonary dysplasia) and periventricular leukomalacia, because of a too low number of newborns in prospective trials. Genital mycoplamas are resistant to beta lactamines. Macrolides have a good sensitivity, particularly josamycine, but Mycoplasma hominis is resistant to erythromycin. For systemic sepsis, fluoroquinolones such as ciprofloxacine have less deleterious effects than IV erythromycin.

Émergence de la résistance aux macrolides chez Streptococcus pyogenes en pédiatrie

A total of 206 recent throat isolates of Streptococcus pyogenes collected between 2002 and 2004 from children were tested for their susceptibility to penicillin, amoxycillin, erythromycin, clarythromycin and clindamycin. The erythromycin resistant isolates were further studied for their genetic mechanism of resistance by means of PCR. In all, 14.5% of the strains were erythromycin resistant and 13.5 and 1% expressed the constitutive MLS(B) and M resistance phenotypes and harbored the ermB and mef A genes respectively.

Sensibilité actuelle en France de Streptococcus pyogenes responsable d’angine aiguë

OBJECTIVE

Current guidelines recommend that only tonsillopharyngitis due to group A beta-haemolytic streptococcus (GABHS) diagnosed by rapid diagnostic test should be treated with antibiotics. Empirical antibiotic therapy must be based on epidemiological surveillance of resistance of GABHS to antibiotics. The aim of our study was to assess the activity of antimicrobial agents currently recommended for the treatment of GABHS tonsillopharyngitis. Method The activity of penicillin G, amoxicillin, cefaclor, cefpodoxime, cefuroxime, erythromycin, clarithromycin and clindamycin was determined against 93 consecutive GABHS isolates collected in 2002. MIC50 and MIC90 of antibiotics tested were determined by agar dilution method according to CA-SFM guidelines. Macrolide resistance genes (ermA, ermB, mef) were detected by PCR. Genetic diversity of erythromycin-resistant isolates was analysed by pulsotypic method after digestion by SmaI (Finger-printing II, Biorad).

RESULTS

The activity of beta-lactam agents tested was similar and no resistant strain was detected (0%). Nevertheless, this study shows an increasing emergence of erythromycin-resistant GABHS strains reaching 14% in 2002 (vs. 6.2% in a previous study carried out in 1996-1999).

CONCLUSION

The empirical antibiotic therapy of tonsillopharyngitis must consider, on the one hand, the high risk of GABHS eradication failure associated with in vitro resistance to erythromycin and clarithromycin, and on the other hand, the sustained susceptibility of GABHS to beta-lactam agents. These results reinforce the recommendations to use beta-lactam agents as first line treatment of GABHS tonsillopharyngitis.

Adénites cervicales suppurées chez l’enfant

OBJECTIVE

To review the bacteriological features and treatment of suppurative cervical lymphadenitis in children in order to achieve optimal treatment.

PATIENTS AND METHODS

Forty-five children were hospitalized. Time of hospitalization was evenly distributed over Year and between Years. Age ranged from 2.5 Months to 13.5 Years (median 1 Year 10 Months). Twenty-nine patients had received prior antibiotic treatment. Bacteriological samples were sterile in 15 out of 45 children and were positive for Staphylococcus (all meti-S) in 20. Cefotoxim and fosfomycin were prescribed and was sufficient in 14 children (with needle aspiration). Surgical drainage was performed in the other cases.

CONCLUSION

Staphylococcus aureus is the predominant causal agent for acute suppurative lymphadenitis in children. Antibiotic therapy in the outpatient setting does not always prevent abscess formation and surgical drainage may be required.

Infections néonatales à Candida

Candida infections in newborns are classified, as bacterial ones, in early onset or maternofoetal infections and late onset diseases, primitive and nosocomial. Candida infections are responsible of less than 1% of early onset sepsis. Their diagnosis is facilitated by suggestive cutaneous lesions which can be associated or not with systemic infection. Candida nosocomial infections are the most frequent, 7% in premature infants < 1500 g; they are associated with a central venous catheter or with cutaneous infection in extremely low birth weight infants. C. albicans is the predominant species in maternofoetal infections, contrary to nosocomial ones where C. parapsilosis is predominant, 60%. Both species are sensitive to fluconazole. Amphotericin B and its lipidic derivative Ambisome is the reference drug. Because of its lower toxicity and simplicity of administration, fluconazole is preferable for sensitive species. Its prophylactic use in colonized premature infants has been recently proposed.

Bactéries pathogènes dans la mucoviscidose

Since the CF gene identification in 1989 and despite the improvement of our knowledge in the physiopathology of the disease, bronchopulmonary infection determines the vital prognosis. Following Staphylococcus aureus infection, patients are colonized or colonized by Pseudomonas aeruginosa, greatly involved in the pulmonary deterioration. Other bacteria may be involved Burkholderia cepacia, Stenotrophomonas maltophilia, Alcaligenes sp. Intensive antibiotic treatment of primocolonisation helps to prevent or delay chronic colonisation. Chronic colonization needs a rational long term antibiotic strategy to prevent the occurrence of multiresistant germs; antibiotic cures are performed every 3 or 4 months before pulmonary exacerbation symptoms.

Clonal relationship between U.S. and French serotype V group B streptococcus isolates

We examined the genetic diversity of serotype V group B streptococcus (GBS) isolates in the Paris area and compared them with the predominant American serotype V clone. Pulsed-field gel electrophoresis yielded 11 patterns for 64 French GBS. One pattern was obtained with 60% of the isolates tested and was indistinguishable from that of the predominant American clone.

Genotypic characterization of Pseudomonas aeruginosa strains recovered from patients with cystic fibrosis after initial and subsequent colonization

Chronic infection by Pseudomonas aeruginosa (PA) in patients with cystic fibrosis (CF) is preceded by a period of colonization and acute infection. Early aggressive antibiotic treatment of initial colonisation may prevent or at least delay chronic pulmonary infection. We initiated treatment with a combination of IV beta-lactam tobramycin, followed by nebulized colistin when PA was first isolated from patients with CF. Subsequent serial PA isolates obtained from these colonized CF patients were characterized by means of molecular methods to determine whether they were genetically related to the initial strain. Initial colonization was eradicated in all 19 patients. All patients reacquired PA within 3-25 months during the 3 years of follow-up. Fourteen patients acquired a new PA strain with a distinct genotypic profile, suggesting a new source of contamination. Five patients had two PA isolates with identical genotypes, suggesting either previous undetected respiratory tract colonization or a persistent environmental source of contamination.

[Tympanostomy tube otorrhea: microbiological epidemiology, pathogen susceptibility to local antibiotics and bactericidal power of the rifamycin-olfloxacin combination]

OBJECTIVE

We studied the microbiological epidemiology of tympanostomy tube otorrhea, rifamycin and ofloxacin sensitivity of pathogens isolated from these otorrheas, and the bactericidal power of the rifamycine-ofloxacin combination.

MATERIAL AND METHODS

A prospective study was conducted in 1997 with cultures of otorrhea aspirates, in vitro study of pathogen resistance to rifamycin and ofloxacin, bacteriocidal study of the rifamycin-ofloxacin combination.

RESULTS

One hundred eight aspirates were obtained from 98 children (mean age 5 years). Ten aspirates were sterile, 32 had more than one pathogen. The more frequent pathogens were Pseudomonas aeruginosa (Pa) (n=35), Staphylococcus aureus (Sa) (n=27), Haemophilus influenae (Hi) (n=12) and Streptococcus pneumoniae (Sp) (n=9). All Hi, all Sp, 86.3% of the Sa (MIC(90) 0.25 mg/l) and none of the Pa were rifamycin sensitive. All Hi, 97.7% of the Pa (MIC(90) 0.5 mg/l), 73,1% of the Sa (MIC(90) 0.24 mg/l) and none of the Sp were ofloxacin sensitive. The rifamycin-ofloxacin combination led to a 4 log CFU/ml decrease in 6 hours for Sp, and in 24 hours for Pa, Hi and Sa.

CONCLUSION

The rifamycin-ofloxacin combination is bactericidal for bacteria causing tympanostomy tube otorrhea. Otic drops with this combination should be considered as the first line treatment for such otorrhea.

[Hemolytic-uremic syndrome: microbiological aspects]

Escherichia coli O157: H7 became an important pathogen starting in the early 1980s. It has caused epidemics and sporadic cases of often bloody diarrhea which may progress to severe hemolytic and uremic syndrome or thrombotic thrombocytopenia purpura. E. coli O157: H7 is mainly transmitted in food, water and interhuman transmission, but direct animal-to-man transmission has also been documented. E. coli O157: H7 can adhere tightly to the enterocyte brush border (eae gene) and produce verotoxins or Shiga-like toxins and hemolysine (ehxA gene). Diagnosis of E. coli O157: H7 infections is based on evidencing the germ in stools and/or by identifying the genes coding for verotoxins or by serology which increased serum titre of specific antilipopolysaccharide antibodies. Antidiarrheal drugs and antibiotics have little place in the treatment of bloody diarrhea. This public health problem, requires careful identification of animal reservoirs and improved population education in food hygiene.

Breast milk transmission of a Panton-Valentine leukocidin-producing Staphylococcus aureus strain causing infantile pneumonia

We report on a 38-day-old infant who developed pleuropneumonia due to a Staphylococcus aureus strain responsible for familial furunculosis, which was acquired by maternal breast-feeding. All isolates from the infant and parents were genetically related by randomly amplified polymorphic DNA analysis and produced Panton-Valentine leukocidin.

[New spectra of resistance of the main bacteria of the respiratory tract]

Management of acute pneumonia requires knowledge of current etiologic agents. Haemophilus influenzae and Streptococcus pneumoniae are the main responsible pathogens. Changes in epidemiology particularly occur in the susceptibility of antibiotics to S pneumoniae which is the main target of antimicrobial therapy.

[Urinary tract infection in the newborn infant]

Urinary tract infection in the first month of life may be revealed by isolated fever, poor weight gain or severe sepsis. It is more frequent in male infants. Escherichia coli is the most common infecting agent. A urinary tract malformation is found in approximately 30% of the cases. In most cases intravenous treatment with an association of cephalosporin and aminoside is efficient. However, because of the possible involvement of an enterococcus, amoxicillin must be added until the result of the urine culture is available. Prophylaxis with oral administration of antibiotics is recommended in case of urinary tract malformation.

Haemolytic uraemic syndrome and Shiga toxin-producing Escherichia coli infection in children in France. The Société de Néphrologie Pédiatrique

We conducted a study to determine the incidence of haemolytic uraemic syndrome (HUS) in children in France and to assess the role of Shiga-toxin-producing Escherichia coli (STEC) infection in the aetiology of HUS. In collaboration with the Société de Néphrologie Pédiatrique we undertook a retrospective review of all cases of HUS hospitalized from January 1993 to March 1995 and a 1-year prospective study (April 1995-March 1996) of epidemiological and microbiological features of cases of HUS. The polymerase chain reaction (PCR) procedure was used to detect stx, eae, e-hlyA genes directly from case stool samples. Serum samples from cases were examined for antibodies to lipopolysaccharide (LPS) of 26 major STEC serogroups. Two hundred and eighty-six cases were reported. The average incidence per year was 0.7/10(5) children < 15 years and 1.8/10(5) children < 5 years. During the prospective study, 122/130 cases were examined for evidence of STEC infection using PCR and/or serological assays and 105 (86%) had evidence of STEC infection. Serum antibodies to E. coli O157 LPS were detected in 79 (67%) cases tested. In conclusion, this study showed that STEC infection is an important cause of HUS in children in France, with a high proportion related to the O157 serogroup.

[Escherichia coli O157:H7, an emerging pathogen]

AN EMERGING PATHOGEN: Escherichia coli O157:H7 became an important pathogen starting in the early 1980s. It has caused epidemics and sporadic cases of often bloody diarrhea which may progress to severe hemolytic and uremic syndromes or thrombotic thrombocytopenic purpura.

TRANSMISSION

E. coli O157:H7 is mainly transmitted in food. Water and inter-human transmission as well as direct animal-to-man transmission has also been documented.

VIRULENCE

E. coli O157:H7 can adhere tightly to the enterocyte brush border (eae gene) and produce verotoxins or Shiga-like toxins and hemolysine (ehxA gene).

DIAGNOSIS

Diagnosis of E. coli O157:H7 infections is based on evidencing the germ in stools and/or by identifying the genes coding for verotoxins or by serology which increased serum titre of specific antilipopolysaccharide antibodies.

TREATMENT AND PREVENTION

Anti-diarrheal drugs and antibiotics have little place in the treatment of bloody diarrhea. This public health problem, requires careful identification of animal reservoirs and improved population education in food hygiene.

[Bacterial concentration in the cerebrospinal fluid in childhood meningitis]

OBJECTIVES

The aim of this study was to analyze the epidemiological evolution of causal germs in meningitis in children aged 1 day to 15 years and determine the relationship between pretreatment concentrations of bacteria in cerebral spinal fluid (CSF), patient age, bacterial species and bacteriological eradication.

PATIENTS AND METHODS

A quantitative analysis of germs was performed in 212 children with bacterial meningitis (mean age 19.8 months).

RESULTS

Bacterial counts ranged from 2.10(1) to 4.10(9) CFU/ml in CSF. Among the 212 patients, 52 (24.5%) had counts 10(7)/ml. Infants had significantly higher counts than the other age groups. Mean counts for Hoemophilus influenzoe serotype B were not different from those for Streptococcus pneumoniae but were significantly higher than for Neisseria meningitidis. Compared with initial germ counts, 98.5% of the CSF specimens were sterile at 24 and 48 hours and 100% at 72 hours.

CONCLUSION

Germ counts were higher in infants.

Enteroaggregative, Shiga toxin-producing Escherichia coli O111:H2 associated with an outbreak of hemolytic-uremic syndrome

Shiga toxin-producing Escherichia coli O111:H2 strains from an outbreak of hemolytic-uremic syndrome showed aggregative adhesion to HEp-2 cells and harbored large plasmids which hybridized with the enteroaggregative E. coli probe PCVD432. These strains present a novel combination of virulence factors and might be as pathogenic to humans as the classic enterohemorrhagic E. coli.