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G Claeys

Publications and source records attributed to G Claeys.

At least 19 recordsLinked to original sources

Effect of fluconazole consumption on long-term trends in candidal ecology.

BACKGROUND: Fluconazole is an antifungal agent that is widely used for the treatment of Candida infection. Because of its favourable safety profile it is extensively used for prophylaxis in patient populations with a substantial risk for Candida infection. At the individual patient level, exposure to fluconazole selects for Candida non-albicans strains such as Candida glabrata and Candida krusei, with reduced susceptibility or intrinsic resistance to fluconazole. The effect of the volume of consumption of fluconazole on candidal ecology, however, is poorly investigated. OBJECTIVES: The long-term effect of fluconazole consumption on distribution of species causing candidaemia was investigated in a university hospital during an 11 year period (1994-2004). METHODS: In a historical cohort the incidence of nosocomial candidaemia (expressed per 100,000 patient days) was linked with volume consumption of fluconazole [expressed as defined daily doses (DDDs) per 100,000 patient days] and evaluated over time. RESULTS: During the study period 308 episodes of candidaemia occurred (63.3% caused by Candida albicans). The incidence of candidaemia varied from 6.0 to 13.8 per 100,000 patient days. The percentage candidaemia caused by Candida non-albicans spp. varied between 21% and 50%. No trends in the number of candidaemias or in the proportion of C. albicans versus Candida non-albicans spp. were observed. Fluconazole consumption was high but stable ranging from 5013 to 6807 DDDs per 100,000 patient days. No relationship could be demonstrated between volume of fluconazole consumption and Candida spp. distribution (Pearson's correlation coefficient: -0.083; P=0.808). CONCLUSIONS: Despite long-term exposure to fluconazole, no change in candidal ecology was observed.

Antifungal Agents↗

Head to head comparison of N-terminal pro-B-type natriuretic peptide and B-type natriuretic peptide in patients with/without left ventricular systolic dysfunction.

BACKGROUND: Human pro-B-type natriuretic peptide is cleaved into the active B-type natriuretic peptide (BNP) and the inactive fragment NT-proBNP. It is unclear if, similar to BNP, NT-proBNP can be used as a marker of impaired left ventricular (LV) ejection fraction (EF). This study evaluated the analytical performance of both assays to detect LV systolic dysfunction. METHODS: In 72 patients with various degrees of left ventricular systolic dysfunction (LVSD), blood analysis for BNP and NT-proBNP was performed prior to cardiac catheterization, using a point-of-care analyzer (Biosite) and a fully automated laboratory analyzer (Roche-Elecsys), respectively. The within-run and between-run imprecision for BNP and NT-proBNP was calculated. RESULTS: Both markers were able to detect impaired LV EF with the largest area under the receiver-operating-characteristic curve for NT-proBNP (NT-proBNP: 0.851 (0.747-0.924); BNP: 0.803 (0.692-0.887) 95% confidence interval; P = 0.07). A significant correlation was observed between BNP and NT-proBNP (r = 0.9; P < 0.0001). Estimating the within-run imprecision, the coefficient of variance for BNP was 3.14% (n = 20, mean 316 ng/L) to 3.32% (n = 20, mean 820 ng/L) and for NT-proBNP 0.9% (n = 20, mean 4390.8 ng/L) to 1.4% (n = 20, mean 225 ng/L). The between-run imprecision for NT-proBNP ranged between 2.1% (n = 20, mean 224.6 ng/L) and 2% (n = 20, mean 4391 ng/L). Optimal discriminator values for BNP and NT-proBNP were 139 ng/L and 358 ng/L, respectively. However, adjusting the BNP cut-off value to 54 ng/L improved the negative predictive value and sensitivity of the assay. CONCLUSION: Similar to BNP, NT-proBNP is a promising marker in identifying LVSD. Although both assays are reliable and have good analytical performance, their diagnostic cut-off value is dynamic and population-dependent. The slightly wider detection range and the more stable structure of NT-proBNP compared to the BNP assay suggest that NT-proBNP could play an additional role in the evaluation of patients with LV systolic dysfunction.

Adult↗

Epidemiology of Pseudomonas aeruginosa in a cystic fibrosis rehabilitation centre.

Pseudomonas aeruginosa is the leading pathogen in cystic fibrosis (CF) lungs. Since there is great concern about clonal spread in CF centres, this study examined the P. aeruginosa genotypes of colonised residents of a CF rehabilitation centre. The isolates from the sputum of 76 P. aeruginosa-colonised patients were genotyped by fluorescent amplified fragment length polymorphism on arrival and departure. A total of 71 different P. aeruginosa genotypes were identified from 749 isolates. Forty-nine patients had one genotype, 20 had two genotypes and seven had three. Forty-four patients had one or more genotypes in common with other patients (i.e. cluster types). Thirty-two patients were colonised by a single genotype not shared by any other patient. Thirty-eight of the 44 patients with a cluster type already carried their cluster type strain(s) on arrival. Patient-to-patient transmission could not be excluded for eight patients. For five of these, this infection was transient. None of the environmental P. aeruginosa isolates had a genotype similar to the patients' genotypes. In summary, most patients were colonised by only one or two P. aeruginosa genotypes and the risk of persistent patient-to-patient transmission was low during the study period (4%). Most patients with a cluster-type strain carried this strain on arrival, indicating that transmission could have happened in the past. No environmental contamination could be established.

Adolescent↗

Ten years phage-typing of Belgian clinical methicillin-resistant Staphylococcus aureus isolates (1992-2001).

Gradual changes have been observed in the phage-types of methicillin-resistant Staphylococcus aureus (MRSA) isolates from Belgian hospitals. A total of 6551 isolates, collected in 93 Belgian hospitals over 10 years (1992-2001), was examined. A decreasing incidence of the main early Belgian epidemic phage-types ([A], [B], [H]*, Jo*) was observed. Since 1997 and 2000, a new series of phage-types ([Hv]*, [J]*, [O]*), which were likely related to the previous group [H]*, have been noted. The general trends were confirmed in two particular hospitals. Local epidemic and/or endemic phage-types were also encountered.

Aged↗

Investigation of the effect of the coronal restoration quality on the composition of the root canal microflora in teeth with apical periodontitis by means of T-RFLP analysis.

AIM: To investigate the effect of the radiographic and clinical quality of coronal restorations on the composition of the root canal flora of teeth with necrotic pulps and teeth with root fillings associated with apical periodontitis. METHODOLOGY: Twenty-eight necrotic pulps and 35 root filled canals with signs of apical periodontitis were studied. Both the coronal filling (presence of radiographically or clinically deficient margins and/or secondary caries) and the root filling (homogeneity and length) were scored. Bacterial root canal samples were taken with sterile paper points under rubber dam and using measures to prevent contamination. A DNA-based nonculture bacterial identification technique was used, namely terminal restriction fragment length polymorphism (T-RFLP) analysis. RESULTS: Twelve samples were negative for bacterial DNA. A total of 33 different terminal restriction fragments (TRFs) were detected. The Fusobacterium nucleatum/Streptococcus mitis group was the most frequently encountered TRF. The mean number of TRFs per necrotic pulp was 6.2 and 5.8 for the groups with acceptable and unacceptable coronal restorations, respectively. This difference was not significant. In the root filled group, these values (respectively, 5.2 and 8.6) were statistically significantly different (P < 0.05). The following parameters in root filled teeth had no significant influence on the mean numbers of TRFs detected: the length and homogeneity of the root filling and the type of tooth (anterior-premolar-molar). CONCLUSION: T-RFLP allowed the rapid assessment of bacterial biodiversity in root canal samples. The technique revealed the presence of bacteria that have rarely been described in the root canals of teeth with apical periodontitis. Biodiversity in the root filled group was high, as compared with culture-dependent studies where monoinfections were more frequently reported. Only in root filled teeth did defective coronal restorations have a statistically significant influence on the mean numbers of detected TRFs per sample.

Adult↗

Towards a Belgian consensus for prevention of perinatal group B streptococcal disease.

BACKGROUND & OBJECTIVES: In Belgium, as in many other countries, group B Streptococcus (GBS) is still the leading cause of sepsis and meningitis in neonates. In 2001, though no Belgian guidelines for their prevention were available, in some hospitals, obstetrical programmes included a GBS prevention policy. With an aim to reach a Belgian consensus for the prevention of perinatal group B streptococcal disease, a national consensum meeting was organized in 2001. We report here our experience and findings of this meeting. METHODS: In November 2001, obstetricians, neonatologists, microbiologists and infectious diseases specialists were invited to participate in a GBS symposium. International and Belgian speakers presented epidemiological aspects, argued comparative cost-effectiveness of different approaches for prevention and debated technical and practical problems. Management of neonates with risk factors for GBS disease and progress in GBS vaccines were also included in the programme. Further results about Belgian obstetricians' practice and compliance to a policy for prevention of neonatal GBS diseases, as answered in two mail surveys, were commented and discussed. In an interactive session at the end, each participant was asked to vote on the key points related to the different steps of the ideal prevention strategy to recommend. RESULTS: For the main questions, 94 per cent of participants choose a screening-based approach and 94 per cent shifted from the current use of ampicillin to penicillin as first choice for antimicrobial prophylaxis. Further, 79 per cent voted for an approach with integrated neonatal prophylaxis for selected neonates at high risk for GBS disease and 47 per cent voted for a strategy based on an intrapartum rapid screening-based approach. INTERPRETATION & CONCLUSION: The state of the question by different speakers, the data from Belgian epidemiology, and the debate about cost-effectiveness of different approaches led to a massive vote in favour of the universal screening-based approach. Based on these results, a working group has been appointed by the Ministry of Health to draft and edit Belgian recommendations for the prevention of perinatal GBS disease.

Belgium↗

Evaluation of six commercial assays for the rapid detection of Clostridium difficile toxin and/or antigen in stool specimens.

OBJECTIVE: To evaluate six commercially available assays for the detection of Clostridium difficile toxin and/or antigen in stool samples: one latex agglutination test (Culturette brand CDT, Becton Dickinson), two ELISAs (Culturette brand Toxin CD, Becton Dickinson, and Ridascreen C. difficile Toxin A/B, R-biopharm), two chromatographic assays (Clearview C. difficile A, Oxoid, and ColorPac Toxin A, Becton Dickinson) and one enzyme immunoassay for the simultaneous detection of C. difficile common antigen and toxin A (Triage C. difficile Panel, Biosite). METHODS: Over a period of 3 months, 366 liquid or semi-liquid stool samples were tested using cell-culture cytotoxin assay as standard, ethanol shock stool culture and latex agglutination (Culturette brand CDT). Of these, 78 samples, positive with at least one of these three methods, and 98 randomly selected negative samples were further evaluated using the other five kits. PCR was also performed on positive cultures to confirm the presence of toxin A and B genes. RESULTS: Triage C. difficile Panel had the best sensitivity (95%), followed by Clearview C. difficile and ColorPac Toxin A (both 89%), Culturette brand Toxin CD (73%), Ridascreen C. difficile Toxin A/B (57%) and Culturette brand CDT (23%). For Triage, the sensitivity of C. difficile antigen detection was 93%, and the sensitivity of toxin detection was lower (77%). Most false-positive results were obtained with the Triage C. difficile Panel (25 specimens) and Clearview C. difficile A (20 specimens). Culturette brand CDT had the best specificity (99%); followed by Ridascreen C. difficile Toxin A/B (97%), Culturette brand Toxin CD (95%), ColorPac Toxin A (89%), Clearview C. difficile A (83%) and Triage C. difficile Panel (75%). The positive predictive values ranged from 68% to 94%, and the negative predictive values from 83% to 98%. CONCLUSIONS: The sensitivity is much higher for Triage and the two new chromatographic assays than for the conventional EIAs. These tests also have a high negative predictive value. For Triage, C. difficile antigen-positive, toxin A-negative results can be obtained; the clinical value of these must be established by additional studies. Overall, the new-generation assays are still less sensitive than the cytotoxin assay; however, they provided same-day results, could be used as a screening test and may be useful in laboratories without tissue-culture facilities. Our results do not allow the recommendation of one single assay for the diagnosis of C. difficile-associated diarrhea. It remains the case that laboratory results must be correlated and interpreted with the clinical presentation of the patient.

Antigens, Bacterial↗

Modified Granada Agar Medium for the detection of group B Streptococcus carriage in pregnant women.

OBJECTIVES: To improve the detection rate of group B streptococci (GBS) in pregnant women, aiming at the prevention of early-onset septicemia in the newborn. METHODS: The yield from culturing two sites, vaginal and anorectal, on a Modified Granada Medium (MGM) was compared with our standard approach of culturing a vaginal swab on blood agar (BA). RESULTS: Samples were processed from 430 consecutive pregnant women. GBS was isolated from the vagina in 11.6% with BA, and in 13.7% with MGM. In 17.0% of anorectal samples, GBS was identified with MGM. The combination of both sites and media had a yield of 20.0%. MGM identified all but six (2%) of 310 GBS strains after aerobic incubation, with use of a cover slide, and missed only three strains (1%) after anaerobic incubation. CONCLUSIONS: Separate culture of vaginal and anorectal samples using the same MGM agar plate resulted in an increase in detection rate for GBS of 76% as compared to BA alone. The technique is simple and results are available after overnight incubation. MGM was confirmed as a specific medium for the identification of GBS, with a sensitivity of 98-99%.

Anal Canal↗

Sexually transmitted infections and reproductive health in Azerbaijan.

BACKGROUND: Little is known about the prevalence of sexually transmitted infections (STIs) and about sexual and reproductive health in Central and Eastern Europe. However, it is clear that major epidemics of STIs currently exist. GOAL: To provide baseline information for the development of national guidelines on the management of STIs in Azerbaijan. STUDY DESIGN: A prevalence study on STIs, including a questionnaire on sexual and reproductive health, in two regions of Azerbaijan targeted three groups: (1) pregnant women, (2) gynecology patients, and (3) men attending a dermatovenereology clinic. RESULTS: The 407 pregnant women in this study had a mean of 1.47 abortions and 1.40 births per woman. Of these women, 12% reported condom use and 41% previous symptoms of a sexually transmitted infection. Active syphilis was found in 1.7% of the women. The 326 gynecology patients had a mean of 2.54 abortions and 2.63 births per woman. Of these patients, 11% reported use of modern contraceptives, 18.3% previous condom use, and 63% previous symptoms of an STI. The prevalence of active syphilis was 2.2%, Chlamydia trachomatis 3.1%, Neisseria gonorrhoeae 2.8%, Trichomonas vaginalis 7.1%, Candida 33.1%, and bacterial vaginosis 32.5%. Of the 197 male patients, 67% reported multiple partners in the past 3 months, 62% money exchanged for sex, 37% condom use ever, and 40% a history of STIs. Active syphilis was found in 9.5% of the men, C trachomatis in 5.9%, N gonorrhoeae in 17%, and T vaginalis in 4.4%. CONCLUSIONS: The data show high-risk behavior in the men attending STI clinics, poor sexual and reproductive health status in the women, and underreporting of official data.

Adolescent↗

Case of catheter sepsis with Ralstonia gilardii in a child with acute lymphoblastic leukemia.

Acute lymphoblastic leukemia was diagnosed in a 7-year-old girl. Two months after insertion of a central venous catheter, she developed fever and complained of headache and abdominal pain. Physical examination revealed no focus of infection. A gram-negative nonfermenting bacillus was recurrently cultured from blood. Extensive biochemical testing and 16S ribosomal DNA sequencing led to the identification of Ralstonia gilardii.

Bacteremia↗

One case each of recurrent meningitis and hemoperitoneum infection with Ralstonia mannitolilytica.

Two clinical cases of infection with Ralstonia mannitolilytica are described: a recurrent meningitis on an implanted intraventricular catheter and an infected hemoperitoneum as a complication of a cholangiocarcinoma. The strains were first misidentified as Pseudomonas fluorescens and Burkholderia cepacia. Further testing lead to the identification as Ralstonia pickettii biovar 3/"thomasii," which was recently shown to represent a separate species, R. mannitolilytica (List editor N. Weiss, Int. J. Syst. Evol. Microbiol. 51:795-796, 2001), originally described as R. mannitolytica (De Baere et al., Int. J. Syst. Evol. Microbiol. 51:547-558, 2001). R. mannitolilytica can be distinguished from all described Ralstonia species by its acidification of D-arabitol and mannitol and by its lack of nitrate reduction and of alkalinization of tartrate. In order to determine the true prevalence of infections with this species, colistin-resistant "P. fluorescens" strains and strains growing on B. cepacia selective medium deserve further attention.

Adult↗

Isolations of Leclercia adecarboxylata from a patient with a chronically inflamed gallbladder and from a patient with sepsis without focus.

Leclercia adecarboxylata was isolated from a patient with a chronically inflamed gallbladder, together with Enterococcus sp. The organism was considered clinically significant and was susceptible to all antibiotics tested. Another strain of L. adecarboxylata was cultured from blood, together with Escherichia hermannii and E. faecalis, from a patient with sepsis.

Aged↗

Turnover of Haemophilus influenzae isolates in otitis-prone children.

Arbitrarily primed PCR with primer ERIC2 and RAPD Ready-to-Go beads was applied to study the epidemiology of non-typable Haemophilus influenzae (NTHI) isolated from the nasopharynx of children with recurrent otitis media (otitis-prone children). Thirty-five otitis-prone children (OP-children) were included. Three pairs of siblings were identified in the study population. This study is part of a large prospective multicentric trial investigating the efficacy of a new conjugated pneumococcal vaccine in OP-children (OMAVAX trial). During a 2-year study period, NTHI strains were isolated from nasopharyngeal swabs and, when possible, middle ear aspirates were collected in OP-children between 1 and 6 years of age. In 20 out of the 35 children, 48 H. influenzae isolates were obtained simultaneously from different sites (left and/or right ear and/or nasopharynx) of the same child as well as from siblings or during initial and follow-up visits of the same child. Subsequent genotyping indicated substantial genetic diversity among the H. influenzae isolates studied, since for a total of 48 isolates in 20 OP-children, 29 different genotypes were observed. Simultaneous isolation for different sampling sites (ear or nasopharynx) as well as for siblings resulted mostly in identical fingerprints. Longitudinal follow-up of H. influenzae isolates in the nasopharynx almost always resulted in different genotypes. We can therefore conclude that both cross colonization (between sampling sites within the same patient and between siblings) and turnover of H. influenzae isolates are high in OP-children.

Belgium↗

Turnover of Haemophilus influenzae isolates in otitis-prone children.

INTRODUCTION: Previous studies have suggested a direct relationship between the nasopharyngeal carriage of potential middle ear pathogens and the development of middle ear disease. It has been shown that otitis-prone (OP) children tend to be colonized more often than non-OP children. To study the turnover of nontypeable Haemophilus influenzae (NTHI) in the nasopharynx of OP children, arbitrarily primed PCR was applied to NTHI strains isolated nasopharyngeal swabs collected prospectively during a 2-year study period from 35 OP children under 4 years of age at fixed intervals. METHODOLOGY/MATERIALS: In 20 patients, H. influenzae could be isolated from different sites (left and/or right ear and/or nasopharynx) or at different occasions during follow-up. Forty-eight H. influenzae isolates of different sites (left and/or right ear and/or nasopharynx) of the same patient as well as from siblings were typed using arbitrarily primed PCR with primer ERIC2 and RAPD Ready-to-Go beads (Pharmacia Biotech, Uppsala, Sweden). RESULTS: Typing with arbitrarily primed PCR enabled to differentiate 29 genotypes among the 48 H. influenzae isolates. Sixteen of these fingerprints were observed only once. Thirteen of these fingerprints appeared on two or more occasions. In the three pairs of siblings the same strain was identified at one moment. Genetically identical NTHI strains from unrelated individuals were never identified. In 11 of 14 cases for which isolates were obtained simultaneously from different sites (throat and/or left ear and/or right ear) or from three pairs of siblings, identical fingerprints were observed. In nine cases whereby isolation was separated by a period of more than 4 weeks (maximum 28 weeks) the fingerprints of the isolates were different from the original isolate. CONCLUSION: Typing with arbitrarily primed PCR indicated substantial genetic diversity among the H. influenzae isolates studied, since for a total of 48 isolates of 20 different patients, 29 different genotypes were observed. Since simultaneous isolation for different sampling sites (ear or nasopharynx) as well as for both of siblings, resulted mostly in identical fingerprints, and since sampling of the same site of the same patient, separated by an interval of more than 1 month, almost always resulted in different genotypes, one could conclude that both cross colonization (between sampling sites within the same patient and between siblings) and turnover are high. The relation between acquisition and development of disease needs further attention.

Child, Preschool↗

Isolation of Moraxella canis from an ulcerated metastatic lymph node.

Moraxella canis was isolated in large numbers from an ulcerated supraclavicular lymph node of a terminal patient, who died a few days later. Although the patient presented with septic symptoms and with a heavy growth of gram-negative diplococci in the lymph node, blood cultures remained negative. M. canis is an upper-airway commensal from dogs and cats and is considered nonpathogenic for humans, although this is the third reported human isolate of this species.

DNA, Ribosomal↗