One-day prevalence of asymptomatic carriage of toxigenic and non-toxigenic Clostridioides difficile in 10 French hospitals.

BACKGROUND: Asymptomatic faecal carriage of Clostridioides difficile has been widely evaluated, but its prevalence across a wide range of clinical departments and related risk factors are not well described. The objectives of the PORTADIFF study were to evaluate the prevalence and identifying risk factors leading to asymptomatic carriage of both toxigenic and non-toxigenic C. difficile. METHODS: The PORTADIFF study was a 1-day prevalence study carried out in 10 different French hospitals. Adult patients, who agreed to participate, were included in this study and provided a fresh stool sample. C. difficile strains isolated from carriage were characterized by polymerase chain reaction (PCR) detection of tcdA, tcdB, cdtA and cdtB, and PCR ribotyping. RESULTS: In total, 721 patients were included in this study. The median age was 73 years (range 18-101 years) and the male/female ratio was 1.06. C. difficile (either toxigenic or non-toxigenic strains) was isolated from 79 (11%) patients; 42 (5.8%) strains were toxigenic. The prevalence rates of asymptomatic carriage ranged from 5% on surgical wards to 19% on long-term care wards. The main risk factors associated with asymptomatic carriage were antibiotic treatment within the preceding 3 months (81.8% vs 53.7%; P<0.01), hospitalization within the preceding 2 months (55.8% vs 33%; P<0.01), cumulative duration of hospital stay before study inclusion (mean 50.1 vs 34.5 days; P<0.047), and hospitalization on a ward with high global incidence of C. difficile infection. CONCLUSION: Eleven percent of hospitalized patients were asymptomatic carriers of toxigenic or non-toxigenic C. difficile, and may constitute a potential reservoir of C. difficile strains.

Carriage of ESBL-producing Enterobacteriaceae in French hospitals: the PORTABLSE study.

BACKGROUND: Currently, contact precautions are recommended for patients colonized or infected with extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE). Recent studies have challenged this strategy. This study aimed to assess the rate of ESBL-PE faecal carriage among hospitalized patients according to type of hospital ward, and to identify risk factors associated with carriage. METHODS: A point prevalence study was conducted in five different types of hospital ward [medical, surgical, intensive care unit (ICU), after care and rehabilitation, and geriatric] in eight French hospitals. All patients included in the study provided a fresh stool sample. RESULTS: In total, 554 patients were included in the study, with a median age of 73 years (range 60-82 years). The overall faecal carriage rate of ESBL-PE was 17.7%. The most frequently encountered species among ESBL-PE was Escherichia coli (71.4%), followed by Klebsiella pneumoniae (14.3%). Risk factors associated with ESBL-PE faecal carriage on univariate analysis were: living in the Paris region (P<0.01) and hospitalization on a geriatric ward (P<0.01). Interestingly, the cumulative duration of hospital stay before screening was not associated with a significantly higher prevalence of ESBL-PE carriage, regardless of ward type. The ESBL-PE colonization rate was much higher for patients hospitalized on geriatric wards (28.1%) and ICUs (21.7%) compared with those for patients hospitalized on surgical wards (14.8%), medical wards (12.8%) or aftercare and rehabilitation (11.2%). CONCLUSION: The overall prevalence of ESBL-PE faecal carriage was 17.7%, with only 21% of patients identified previously as carriers. The delay between admission and screening was not associated with an increase in ESBL-PE faecal carriage.

[Comparison of three Clostridium difficile culture media: interest of enhancing spore germination media?]. / Comparaison de trois milieux pour la culture de Clostridium difficile: intérêt des milieux favorisant la germination des spores?

AIM: Clostridium difficile is the most common agent of postantibiotic and nosocomial bacterial diarrhoea. Since the emergence of the highly virulent and epidemic strain NAP1/027 in Europe, it appears necessary to isolate C. difficile strains to realize an epidemiologic follow-up by molecular typing. The aim of this work was to compare three selective culture conditions for the isolation of C. difficile. METHODS: One hundred and thirty stools collected from patients hospitalized at Jean Verdier were swabbed on the commercial medium CLO (BioMérieux) and on a medium prepared at the laboratory (CCTa: Columbia, cefoxitine 8 mg/l, cycloserine 250 mg/l, horse blood 5 %, sodium taurocholate 0.1 %) with and without preliminary alcoholic shock (EtOH). C. difficile was isolated from 38 stools and colonies were counted on each medium. RESULTS: The fluorescence intensity of C. difficile colonies is comparable on CLO and CCTa-EtOH media, however their aspect is more characteristic on CLO. This medium appears very selective contrary to the CCTa medium on which an associated flora obstructs the fluorescence reading and requires a new isolation of the suspect strains. On average 30 times more colonies of C. difficile are counted on CCTa+/-EtOH than on CLO, suggesting the presence of great proportions of spores in the stools. CONCLUSIONS: The medium CLO is successful for the isolation of C. difficile despite of its selectivity. Nevertheless, it appears interesting to associate a medium enhancing spore germination as the CCTa medium inoculated after alcoholic shock to increase the sensitivity of detection while being freed from conservation and transport conditions.

[Pregnancy associated Plasmodium falciparum malaria discovered fortuitously: report of two cases]. / Découverte fortuite de paludisme àPlasmodium falciparum au cours de la grossesse : à propos de deux cas.

We report two cases of pregnancy-associated Plasmodium falciparum malaria discovered fortuitously. These two women were born in Africa and their last visit in an endemic area was more than one year before. It is well known that pregnancy is one of major risks of late onset of P. falciparum malaria. In the two cases reported in this study, clinical signs of malaria were not specific and we will describe the interest to detect more systematically pregnant African women, first arrival immigrants.

New trends in Clostridium difficile virulence and pathogenesis.

The disease spectrum caused by Clostridium difficile infection ranges from antibiotic-associated diarrhoea to life-threatening clinical manifestations such as pseudomembranous colitis. C. difficile infection is precipitated by antimicrobial therapy that causes a disruption of the normal colonic microbiota, predisposing to C. difficile intestinal colonisation. The pathogenicity of C. difficile is mediated by two exotoxins, TcdA and TcdB, both of which damage the human colonic mucosa and are potent cytotoxic enzymes. C. difficile must first be implanted in the gut and attach to epithelial cells, which are protected by a layer of dense mucus. Confirmed and putative accessory virulence factors that could play a role in adherence and intestinal colonisation have been identified and include proteolytic enzymes and adhesins. Recently, the epidemiology of C. difficile infection has radically changed and an increased incidence is associated with outbreaks in North America and Europe. Several reports suggest that disease severity is increasing to include sepsis syndrome and toxin megacolon. Elderly, debilitated patients in hospitals and nursing homes are particularly vulnerable. A hypervirulent, epidemic strain has been associated with the changing epidemiology and severity of disease. Here, we review the characteristics of the epidemic NAP1, PCR ribotype 027 C. difficile strain that could explain its hypervirulence and epidemic spread.

[Epidemiological study of Clostridium difficile strains isolated in Jean-Verdier-René-Muret hospitals from 2001 to 2007]. / Evolution épidémiologique de souches de Clostridium difficile isolées d'infections dans le CHU Jean-Verdier-René-Muret entre 2001 et 2007.

Clostridium difficile is the most common agent of nosocomial bacterial diarrhoea in adults. In 2006, C. difficile outbreaks were described in France with the highly virulent strain PCR-ribotype 027, which is also resistant to moxifloxacin and erythromycin. The aim of this study is to perform a phenotypic and molecular characterization of C. difficile strains isolated in Jean-Verdier-René-Muret hospitals. Thirty three C. difficile toxigenic strains isolated in symptomatic patients from 2001 to 2007 were studied. Toxins A and B detection was performed with an immunoenzymatic method (ICTAB, Meridian). The agar diffusion method was performed for determination of antibiotic susceptibility for metronidazole, vancomycin, erythromycin and moxifloxacin. The E-test was performed for determination of metronidazole, vancomycin and tigecycline MIC. Binary toxin genes cdtA and cdtB were detected by PCR. PCR-ribotyping was performed according to Bidet et al. From 2001 to 2007, all the isolates studied were susceptible to metronidazole, vancomycin and tigecyclin. We observed a significant decrease of susceptibility to moxifloxacin (100% in 2001 versus 28.5% in 2007) and to erythromycin (60% in 2001 versus 14% in 2007). Toxins A/B were detected in all the isolates. Fifteen per cent of the isolates studied produced the binary toxin not correlated with a specific PCR-ribotype. Ribotype 18 was the most prevalent PCR-ribotype detected since 2006. The isolates displaying this PCR-ribotype were resistant to erythromycin and moxifloxacin and were principally isolated in the same ward, suggesting cross infection. This study showed that: (1) over a six-year period, the susceptibility to metronidazole and vancomycin remained stable; (2) different clones of C. difficile circulated during these six years. Recently an epidemic strain resistant to erythromycin and moxifloxacin of ribotype 18 has emerged in the gastroenterology unit where fluoroquinolones are frequently used demonstrating the role of antibiotic selection pressure. The emergence of these isolates could explain the significant decrease of susceptibility to moxifloxacin and erythromycin observed in 2007. However, today, no isolate with a PCR-ribotype 027 was detected.

Comparative in vitro activities of caspofungin and micafungin, determined using the method of the European Committee on Antimicrobial Susceptibility Testing, against yeast isolates obtained in France in 2005-2006.

The in vitro activities of caspofungin and micafungin against 1,038 yeast isolates have been determined. The caspofungin and micafungin MICs were lower for Candida albicans, Candida glabrata, and Candida tropicalis than for Candida parapsilosis, Candida guilliermondii, and Candida krusei. A clear correlation was seen between the MICs for the two drugs.

[Interest of the disk diffusion method for screening Clostridium difficile isolates with decreased susceptibility to antibiotics]. / Evaluation de l'antibiogramme par diffusion en milieu gélosé pour le dépistage de souches de Clostridium difficile de sensibilité diminuée aux antibiotiques.

AIM: In vitro determination of Clostridium difficile susceptibility to antibiotics is not routinely performed. The aim of this study was to evaluate the performance of antibiotic susceptibility determination with the disk diffusion method for screening C. difficile isolates with decreased susceptibility to antibiotics. METHODS: Thirty-six C. difficile isolates (toxigenic or not) isolated in 2005 and 2006 from three hospitals Assistance publique-Hôpitaux de Paris (Jean-Verdier, René-Muret, Beaujon) were studied by disk diffusion method with 14 antibiotics. Mueller-Hinton agar supplemented with sheep blood (Bio-Rad*) were swabbed with a C. difficile suspension at 1 McFarland. To check the results obtained with the disk diffusion method, Minimal Inhibitory Concentration (MIC) were performed respectively with E-test for glycopeptides and metronidazole and with the agar dilution reference method and E-test for new molecules with a potential activity against anaerobes: imipenem, ertapenem, linezolid and moxifloxacin. RESULTS: The decreased susceptibility (resistant and intermediate) observed was 40% for amoxicillin-clavulanate, 60% for piperacillin-tazobactam, 100% for ceftriaxone, 81% for imipenem, 61% for ertapenem, 2% for chloramphenicol, 34% for erythromycin, 90% for lincomycin, 2% for linezolid, 98% for levofloxacin, 17% for moxifloxacin and 0% for vancomycin, teicoplanin and metronidazole. The results obtained with the disk diffusion method were compared to MICs obtained with E-test and reference method. CONCLUSION: The disk diffusion method seems to be a good method to detect isolates suspected to have a decreased susceptibility and consequently to reduce MIC determinations.

[In vitro activity of moxifloxacin (8-methoxyquinolone) alone or in combination with cefotaxime against group B streptococci]. / Activité in vitro de la moxifloxacine (8-méthoxyquinolone) seule ou en association avec le céfotaxime sur les streptocoques du groupe B.

AIM OF THE STUDY: Our objective is to determine in vitro efficiency of moxifloxacin (MXF) alone or in combination with cefotaxime (CTX) on Group B streptococcus (GBS). MATERIALS AND METHODS: For 21 strains of GBS isolated from newborn invasive infections (6 meningitis and 15 bacteraemia), the bacterial growth in Mueller Hinton broth with MXF and/or CTX leaded to the determination of MIC and MBC, the determination of tolerance for CTX and the evaluation of the bacteriostatic action of these antibiotics combination by calculating the FIC index. Time-kill studies were conducted for MXF and CTX alone or in combination for the first four hours, with concentrations likely reached in CSF. RESULTS: Study of GBS growth with crossed concentrations of MXF and CTX showed no resistant strains, no tolerant strains, and no antagonism between MXF and CTX. Killing curves demonstrated that MXF is ten-fold more active than CTX in the first four hours. DISCUSSION: MXF is an interesting antibiotic for its good activity on the GBS, suggesting that MXF is a good candidate for further evaluation in GBS meningitis in animal model.

[Evaluation of four immunoenzymatic tests for detecting Clostridium difficile toxins A and B]. / Evaluation de quatre réactifs immunoenzymatiques pour la recherche des toxines A et B de Clostridium difficile.

Four immunoenzymatic tests for detecting Clostridium difficile toxins A and B were studied: two rapid tests (Tox A/B QUIK CHEK-Techlab and NoviView Toxine-A-Hiss diagnostics) and two Elisa tests (C. difficile TOX A/B II -Techlab and Toxin A+B Elisa Test, Novitec-Hiss diagnostics). The results were compared to those obtained with ImmunoCard Tox A+B -ICTAB (Meridian), C. difficile Toxine A (Oxoid) for rapid test and Elisa Premier A+B Meridian for Elisa. A total of 41 stools and 16 isolates were studied with rapid tests. On stools, the sensitivity and specificity of QUIK CHEK test was 94.1% and 100% respectively compared to the test ICTAB. On the isolates, sensitivity and specificity was 100%. With the Noviview test, the sensitivity on stools and isolates was respectively 88.2 and 85.7% and the specificity was 100% compared to Oxoid. A total of 38 stools were studied with Elisa tests. With Techlab test compared to the test Premier, sensitivity and specificity was 100%. The Novitec test gave five false negative reactions with consequently a sensitivity of 70.6%.

Report of a case of congenital malaria Plasmodium malariae in France.

Congenital malaria (CM) has been considered to be rare, even in malaria-endemic areas but the disease can result in significant neonatal morbidity. Because of its rarity, the disease may go undiagnosed for a prolonged period in a seriously ill infant. We report the first case of Plasmodium malariae CM from a HIV mother. HIV could have facilitated the transfer of erythrocytic persistent P. malariae through the placenta to the fetus.

[Congenital malaria as a result of Plasmodium malariae in an infant born to a HIV-seropositive woman]. / Paludisme congénital à Plasmodium malariae chez un nouveau-né de mère séropostive pour le VIH.

Congenital malaria is uncommon in France. The purpose of this report is to describe a case involving a six-week-old infant who was hospitalized with fever, hepatosplenomegaly, anemia and thrombopenia. Thick and thin blood smears were positive for Plasmodium malariae. The infant responded favorably to chloroquine. Based on this experience, we performed a search of the literature to find case reports on congenital malaria in France and compare clinical and epidemiologic data with series reported in the United States and from endemic areas. The placenta appears to provide an effective barrier against Plasmodium since infection is much more common than disease. The delay for onset of clinical symptoms is longer in temperate zones than in endemic areas. The type of parasite could account for this difference since African congenital malaria are due to Plasmodium falciparum while most cases described in the United States are due to Plasmodium vivax. We also discuss the possible implications of coinfection by HIV in the mother.

[Epidemiology and antimicrobial resistance of Streptococcus pneumoniae strains isolated in Ile de France area during 2001]. / Epidémiologie et résistance aux antibiotiques de Streptococcus pneumoniae en Ile de France en 2001.

OBJECTIVE: The authors wanted to assess the level of Streptococcus pneumoniae antibiotic resistance in Ile de France. METHOD: In 2001, 637 clinical strains of S. pneumoniae were prospectively collected from 32 microbiology laboratories. RESULTS: Fifty one percent of strains were isolated from children under 15 years of age and 49% from adults. In children, 76% of strains came from otitis media, 20% from blood culture, in adults most strains (92%) came from blood culture. The overall prevalence of non-susceptible penicillin pneumococci was 61% higher in children (73%) than in adults (50%). Among the non-susceptible penicillin pneumococci 21.8% were resistant (CMI > 1 mg/l). Strains with decreased susceptibility to amoxicillin and cefotaxime were 38% and 17% respectively. Resistant strains to these two drugs (CMI > 2 mg/l) were rare 2.6% and 0.4% respectively. Among other antimicrobial agents, rate of resistance was 63% to erythromycin, 47% to cotrimoxazole, 40% to tetracycline, and 23% to chloramphenicol. The most frequent serogroups were serogroups 19 and 14, respectively 23% and 18%. Serotypes included in heptavalent vaccine covered 90% of children strains under 2 years of age. CONCLUSIONS: The prevalence of resistance to penicillin was high in children particularly in otitis media pus (76%).

[Susceptibility of Clostridium difficile to metronidazole using the E-test: effect of the culture medium]. / Sensibilité de Clostridium difficile au métronidazole par le E-test: influence du milieu de culture.

The treatment of intestinal Clostridium difficile infections rests on administration of either a glycopeptide or metronidazole. Given the current shifts in resistance patterns of anaerobes to antimicrobials, a study of the susceptibility of C. difficile to metronidazole was timely. The objective of this study was to evaluate the influence of the culture medium on the Minimal Inhibitory Concentration (MIC) of metronidazole as determined using the E-test. Thirty-one strains were grown on three different media supplemented with 5% horse blood, namely Columbia agar, Wilkens Chalgren agar, and Brucella agar. Results were compared to those obtained using the reference agar dilution method (ADM). As recommended by the French Society for Microbiology, susceptibility was defined as an MIC < or = 4 mg/L. When used on strains susceptible by the ADM, the E-test yielded lower values than the ADM with all three media. Furthermore, findings suggest that E-test results obtained with strains whose MIC is in the 4 to 8 mg/L range by the ADM should be interpreted with caution and, in some cases, tested using the ADM.

Protease activity of Clostridium difficile strains.

The production of proteolytic enzymes by 10 Clostridium difficile isolates of varying toxigenicity and clinical origin was studied to determine if all isolates secreted proteases. Different protease substrates were studied: gelatin, collagen, phenylazobenzyloxycarbonyl-leucyl-glycyl-L-prolyl-D-arginine (Pz-peptide), casein, azocasein, and azocoll. All isolates degraded gelatin, collagen, and azocoll. The supernatants of all isolates contained an enzyme capable of attacking gelatin incorporated in a polyacrylamide gel (zymograms) and forming two closely spaced lytic bands with an estimated molecular mass of 35-40 kDa. Polyclonal antibodies, produced against the C. difficile gelatinase, revealed in Western blots a 35-kDa protein in the culture supernatants of all C. difficile isolates. In the same manner, Clostridium perfringens collagenase polyclonal antibodies detected a 120-kDa protein in the culture supernatants of all isolates; this suggests that at least two proteases may exist in C. difficile. The protease activities of the 10 strains examined did not seem strikingly different quantitatively but were in general weak and their role in pathogenicity is suspect.

Acute respiratory distress syndrome due to falciparum malaria in a pregnant woman.

We report the case of a pregnant woman (29th week), living in a Paris suburb, about 20 miles from an international airport. She presented with septic shock and severe acute respiratory distress syndrome (ARDS). A few parasitized erythrocytes were discovered in a hemorrhagic bronchoalveolar lavage (BAL), specimen and many were found on examination of the placenta after a caesarean section had been performed. The patient's condition dramatically improved once given quinine therapy. This is an uncommon case on account of: (1) the unusual clinical course with no organ failure but ARDS, (2) the unusual way the diagnosis was made, (3) the very unusual way the patient became contaminated (airport malaria), (4) the pregnant condition of the patient.

Evaluation of a rapid agglutination test for detection of group B streptococci in the gastric aspirates of neonates.

A rapid commercial agglutination test (Bactigen Strepto B) for detection of group B streptococci in gastric aspirates of neonates was evaluated. One hundred and sixty-one gastric samples were analyzed with conventional bacteriological techniques and with the commercial test after modification of the extraction technique. The sensitivity of the test relative to the culture technique was 90.4%, the specificity 94.2%, the positive predictive value 70.3% and the negative predictive value 98.5%. The commercial test could be performed in one hour and showed good sensitivity and specificity. If a test result was negative colonization could be excluded, obviating the need for empirical antibiotic therapy, whereas a positive result suggested colonization or neonatal infection with group B streptococci.

Corynebacterium diphtheriae osteomyelitis in an immunocompetent child: a case report.

UNLABELLED: Septic osteomyelitis of the hip in a previously healthy child is described. A weakly toxigenic Corynebacterium diphtheriae strain was isolated from the bone aspirate. The results of the treatment were rapidly satisfactory, after surgical drainage and antibiotic therapy with pristinamycin. CONCLUSION: This case report shows that C. diphtheriae has not disappeared in the developed world and can be responsible of systemic infections.

Enterobacter cloacae cross-colonization in neonates demonstrated by ribotyping.

The intestinal colonization by Enterobacter cloacae strains with a derepressed cephalosporinase was studied in a paediatric ward between February 1990 and January 1991. Environmental sampling was performed simultaneously. Fifty-two isolates were recovered from 200 neonates (stool, blood) and 14 strains were isolated from the neonatal environment. An epidemiological study based on the typing of 36 Enterobacter cloacae isolates was carried out using antibiotyping, biotyping and ribotyping methods. The isolates selected were from 21 neonates (24 isolates), the neonatal ward environment (8 isolates) and from other wards (4 isolates). Thirty-two isolates had the same antibiotic resistance pattern, corresponding to a derepressed cephalosporinase and resistance to the following aminoglycosides: kanamycin, gentamicin, tobramycin and netilmicin. No predominant biotyping pattern could be established. Ribotyping done with two endonucleases (EcoRI and BamHI) showed 28 Enterobacter cloacae isolates to have a single pattern. Ribotyping was the most discriminating method used in this study, permitting identification of cross-contamination with Enterobacter cloacae in the paediatric ward.