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J L Koeck

Publications and source records attributed to J L Koeck.

At least 19 recordsLinked to original sources

Clinical evaluation of the gen-probe amplified mycobacterium tuberculosis direct test for rapid diagnosis of tuberculosis lymphadenitis.

This prospective study evaluated the performance of the Amplified Mycobacterium Tuberculosis Direct Test (MTD) for the diagnosis of lymph node tuberculosis in Djibouti, Republic of Djibouti. Of 197 specimens sampled from 153 patients, 123 were from 95 tuberculous patients. The sensitivity and specificity of MTD were 93 and 100%, respectively. The sensitivity of culture was 89%.

Culture Media↗

[Outbreak of tropical phagedenic ulcers after the rainy season in Dijibouti].

The incidence of cutaneous ulcers was observed after the rainy season in Djibouti in 1997. Based on the study of epidemiologic, clinical, biological, and therapeutic features these lesion were classified as phagedenic ulcers. While direct examination showed numerous fusiform bacilli, cultures performed in one patient, led to isolation of numerous colonies of Prevotella loescheii. Though less common, two other anaerobic bacterial species were detected, i.e., Peptostreptococcus anaerobius and Peptostreptococcus sp.

Adolescent↗

[Antibiotic sensitivity of Salmonella isolated in army hospitals between 1998-1999].

OBJECTIVES: Monitor the evolution in France of antibiotic sensitivity of non-typhoid salmonella isolated in fecal cultures conducted in army hospital laboratories. METHODS: A prospective study was performed from January 1998 to December 1999 in all the biology departments of the 11 army hospitals in France. All the non-repetitive strains were sent to an official center for serotyping and determination of the minimum inhibiting concentrations, by dilution in Mueller Hinton's gelose. The antibiotics currently used in treatment were tested and interpretation endpoints followed the recent recommendations of the Antibiogram committee of the French society of microbiology. Identification of beta-lactamase was conducted by iso-electric focalization and polymerization by chain reaction (PCR). For Salmonella Typhimurium, research for the specific resistance locus of the DT104 clone was made using PCR. RESULTS: Two hundred and twenty-two non-repetitive salmonella strains were isolated. The principle serotypes found were: Salmonella Enterididis (23.9%), S. Typhimurium (21.2%) and S. Hadar (10.8%). All the strains were sensitive to ciprofloxacin and cefotaxim, whereas one third exhibited reduced sensitivity to aminopenicillin. Depending on the serotype, Typhimurium and Hadar serotypes exhibited significantly lesser sensitivity to aminopenicillin, nalidixic acid and tetracycline. For S. Typhimurium, resistance is related to the diffusion of the multiresistant DT104 clone, which involves half of the strains of this serotype. For S. Hadar, 18 out of 24 strains (75%) were resistance to nalidixic acid, and 5 of them exhibited reduced resistance to ciprofloxacin. There was no difference in sensitivity to antibiotics between the strains responsible for diarrhea and those isolated in systematic examinations for capacity to work in the food trade (respectively 54 and 46% of strains). CONCLUSION: Non-typhoid salmonella are frequently isolated in diarrhea of infectious origin. The increasing resistance to antibiotics is primarily related to the diffusion of the DT104 clone, regarding S. Typhimurium and to the increase in resistance to quinolone, regarding S. Hadar.

Anti-Bacterial Agents↗

Surveillance of methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE) in Northern France: a five-year multicentre incidence study.

In order to measure the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and of Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE), and to evaluate the impact of the national guidelines for multidrug-resistant bacteria (MDRB) prevention in hospitals of Northern France, a multicentre study was conducted for three months every year starting in 1996, in volunteer hospital laboratories. All clinical specimens positive for MRSA and ESBLE were prospectively surveyed. During the five-year surveillance period, the overall proportion of MRSA was 38.4% in the 28,534 strains of S. aureus, and that of ESBLE was 11.4% in the 6121 strains of Klebsiella pneumoniae and 47.7% in the 2353 strains of Enterobacter aerogenes. The overall incidence rates of clinical specimens positive for MRSA, ESBL-K. pneumoniae and E. aerogenes were 0.84. 0.05 and 0.12/1000 hospital-days (HD), respectively. In the 23 hospitals that participated in the survey every year, the proportion and incidence of ESBLE decreased. Hence, despite recommendations as for isolation precautions, MRSA remains poorly controlled and requires more effective measures.

Anti-Bacterial Agents↗

[Epidemiology of resistance to antituberculosis drugs in Mycobacterium tuberculosis complex strains isolated from adenopathies in Djibouti. Prospective study carried out in 1999].

Tuberculosis is a major cause of death in the Republic of Djibouti. Tuberculous lymphadenitis represents about 25% of the clinical forms of tuberculosis in this country. Between January 1999 and April 1999, 196 lymph node specimens were consecutively collected from 153 patients living in Djibouti. Testing of susceptibility to the major anti-tuberculosis drugs was performed by the proportion method. Growth of Mycobacterium tuberculosis complex strains was obtained from specimens of 85 patients including 9 with prior treatment. Strains were identified as Mycobacterium tuberculosis in 78 cases, Mycobacterium canetti in 3, Mycobacterium africanum in 3, and Mycobacterium bovis in 1. Prevalence of HIV infection was 15%. Assessment of primary resistance demonstrated that the overall resistance rate, i.e., resistance to 1 or more drugs, was 18 (21.2%). Results showed resistance to isoniazid (H) in 6 cases (7.1%), rifampicin (R) in 3 (3.5%), ethambutol (E) in 1 (1.2%), streptomycin (S) in 13 (15.3%) and pyrazinamide (Z) in 1 (1.2%). Multidrug resistance (MDR) was found in 2 cases (2.4%). Assessment of acquired resistance demonstrated resistance to H in 4 cases (44%), R in 2 (22%), S in 2 (22%), E in 0, Z in 0 and MDR in 1 (11%). These findings were not significantly different from data obtained from sputum samples analysed between 1997 and 2000 or from those described in a study conducted in 1985.

Antitubercular Agents↗

[Status of resistance of HIV-1 strains in Africa: what is the role of viral surveillance networks?].

The human immunodeficiency virus (HIV-1) epidemic has spread dramatically in sub-Saharan African countries. Implementation of active antiretroviral (ARV) therapy programs is urgently needed. However this emergency situation must not extenuate the importance of preliminary studies on ARV resistance of African HIV-1 isolates. Findings show that genetic mutations underlying the resistance of African strains are generally identical to those observed in HIV-1 subtype B in industrialized countries. However the incidence of some mutations associated with mild resistance to protease inhibitors (PI) appears higher in African isolates. The potential impact of these mutations for development of frank resistance to PI is still unclear. The incidence of high-grade resistance markers in untreated subjects is low. While these results do not compromise use of ARV therapy in Africa, they underline the need to set up local networks for patient follow-up and to carry out epidemiological surveillance of HIV-1 resistance. Success of ARV therapies in Africa will also depend on economic and social programs.

Africa↗

[Sensitivity to antibiotics of bacteria from nosocomial infections. Evolution in resuscitation services of military hospitals].

OBJECTIVE: The aim of this study, conducted in the French Military hospitals, was to monitor the course of the antimicrobial sensibility of bacteria isolated from nosocomial infection in intensive care units. PATIENTS AND METHODS: A prospective study has been conducted from January to December 1998 in all the intensive care units of the French Army. All the non-repetitive strains isolated from nosocomial infection were collected and sent to a reference centre. Antimicrobial susceptibility was determined by the agar dilution method. Beta-lactamase were identified by iso-electro-focalisation. Antibiotics choice and interpretative criteria were those of the "Comité Français de l'Antibiogramme de la Société Française de Microbiologie". RESULTS: A total of 849 strains are included in this study. Pseudomonas aeruginosa was the most frequently isolated bacterium (20%) followed by Escherichia coli (19%) Staphylococcus aureus (15%), coagulase-negative Staphylococci (CoNS) (11%) and Enterococci (7%). Imipenem was the most effective antibiotic against enterobacteriaceae (336 isolates; 100% susceptibility). Gentamicin (92%), amikacin (92%) third generation cephalosporins (83%), aztreonam (83%) and ciprofloxacin (78%) were also very effective. Resistance to III generation cephalosporins was correlated with an extended spectrum beta-lactamase (BLSE) in 36% of cases. This BLSE could be associated with an over production of the constitutive cephalosporinase. The most frequent species producing BLSE were Enterobacter aerogenes (75% of BLSE) and Klebsiella pneumoniae (17%). Among the 172 P. aeruginosa isolated, antimicrobial susceptibility were respectively: 71% for imipenem, 62%: tobramycin, 60%: amikacin 59%: ciprofloxacin 59% piperacillin + tazobactam, 55% piperacillin, 53%: ceftazidime and 44% for ticarcillin. Seventy per cent of the 96 CoNS and 50.2% of the 126 S. aureus isolated were resistant to methicillin. A strain of S. aureus and 2 CoNS strains had intermediate resistance to teicoplanin. Twenty per cent of the 59 Enterococci strains isolated were resistant to aminopenicillins (10/11 strains of E. faecium), and 9% presented a high level of resistance to gentamicine. One strain of E. faecium was resistant to vancomycin. CONCLUSION: The evolution of the susceptibility to antibiotics in intensive care units reflects the antibiotic pressure and level of cross-transmission. High rates of meticillin-resistance among staphylococci, of resistance to beta-lactams antibiotics among P. aeruginosa and of ciprofloxacin among Enterobacteriaceae are shown in this study. The implementation of appropriate strategies for surveillance and prevention is necessary.

Bacterial Infections↗

[First confirmed case of laryngeal diphtheria in Djibouti].

The first bacteriologically confirmed case of laryngeal diphtheria in Djibouti was reported in 1998. It involved a three-year-old native-born infant who had been vaccinated during the first year of life with three doses of a combined vaccine against diphtheria, tetanus, poliomyelitis, and pertussis. A rapid clinical improvement was observed under erythromycin treatment. Other cases of laryngeal diphtheria have been observed. It is important to reverse decreasing vaccinal coverage in Djibouti and to warn incoming travelers of the need to be adequate immunized against diphtheria. Enhanced epidemiologic surveillance of this disease is also needed.

Child, Preschool↗

[Discovery of a focus of intestinal bilharziasis in te Republic of Djibouti].

An unprecedented pocket of intestinal schistosomiasis was discovered in the Republic of Djibouti in 1997. The first cases were diagnosed in French and Djiboutian tourists who presented initial symptoms of bilharzian infection after bathing in the fresh-water basin under Hassan Gari Bira Falls, near Randa. Seventeen cases were subsequently confirmed by detection of anti-schistosome antibodies using indirect hemagglutination (IH) and indirect immunofluorescence (IIF) and/or detection of Schistosoma mansoni eggs in the stool. Further testing was performed in 35 village inhabitants, mostly children, who had been exposed by bathing in the basin. The IH reaction was positive in 28 patients (80 p. 100) including 17 (49 p. 100) with levels greater than 1/64. In 92 p. 100 of cases, IH findings were confirmed by IIF which indicated that association with hypereosinophilia was common. Schistosoma mansoni eggs were found in stools from 7 patients (19 p. 100) who generally displayed mild hypereosinophilia. Information concerning the zone of risk was distributed and control measures were undertaken as widely as possible in Djibouti and abroad.

Adolescent↗

[Topicality of serologic screening of human immunodeficiency virus infections in adults].

Enzyme immunoassay is the basic method for the detection of antibodies to the Human Immunodeficiency Virus (HIV). In spite of the apparent facility of the serological screening, the difficulties are real at all stages of the analysis. Specimen treatment needs defined rules to avoid contamination. The products authorized are listed by the "French Drug Agency". The specificity cannot be less than 99.5%, and the sensitivity must be of 100%. Each biologist have to acquire its own experience of the tests utilised. To the very recent seroconversions, he must define decision criteria for the pursuit or not of the investigations. False positive have been observed for patients with autoimmune pathology, but was usually related to a disparity between kit lots.

AIDS Serodiagnosis↗

A plasmid-mediated CMY-2 beta-lactamase from an Algerian clinical isolate of Salmonella senftenberg.

Multiresistance to antibiotics including beta-lactams, e.g. cefoxitin, was transferred by conjugation to Escherichia coli strain C1a from a clinical isolate of Salmonella senftenberg recovered from stools of an Algerian child. The susceptibility pattern to beta-lactams was similar to the profile mediated by an AmpC-type beta-lactamase. By biochemical analysis, typical AmpC-type enzyme substrate and inhibition profiles were obtained. Finally, an ampC plasmid-encoded beta-lactamase gene was cloned and sequenced. Its deduced amino acid sequence confirmed its identity as a class C beta-lactamase. It showed 99.5% sequence identity with the plasmid-mediated beta-lactamase CMY-2. The differences in the amino acid sequences of the two enzymes were located in the signal peptide.

Algeria↗

[Antibiotic sensitivity of aerobic gram-negative bacilli isolated from severe infections in 1992: results of a French multicenter study. Groupe d'Etude d'Infections à bacilles à Gram Négatif (GEIGN)].

OBJECTIVES: Antibiotic susceptibility of 649 gram-negative bacilli involved in severe infections and isolated in 18 teaching hospitals from January to December 1992 was evaluated. METHODS: Minimal Inhibitory Concentrations were determined by agar dilution method for piperacillin, piperacillin+ tazobactam and imipenem, and by a microdilution method for 11 other antibiotics (amoxicillin, amoxicillin + clavulanic acid, cefotaxime, ceftazidime, aztreonam, ticarcillin, ciprofloxacin, fosfomycin, tobramycin, gentamicin, amikacin). Criteria of Comité Français de l'Antibiogramme de la Société Française de Microbiologie were followed for interpretation. Betalactamases were identified by isoelectric focusing and overproduction of cephalosporinase was defined by the resistance phenotype. The main species isolated were Escherichia coli (45%), Pseudomonas aeruginosa (14%), Klebsiella pneumoniae (7.8%), Salmonella spp. (7.5%), Enterobacter cloacae (4%) and Klebsiella oxytoca (4%). Most of the strains were isolated from blood culture (72.3%), respiratory tract (11.4%) and intraabdominal infections (8.6%). Most of the enterobacteria isolates were susceptible to imipenem, aztreonam, amikacin and ciprofloxacin (percentages of susceptibility were respectively 99.3, 98, 98.3 and 96.3); in most of cases clavulanic acid did not entirely restore sensitivity to amoxicillin of penicillinase-producing strains. Among 89 P. aeruginosa strains, 82% were susceptible to imipenem and ceftazidime, 81% to the association piperacillin + tazobactam and 51% to ticarcillin. Resistance rates are very high for Acinetobacter baumannii except for imipenem. CONCLUSION: Production of TEM-type penicillinase and over-production of the chromosomal cephalosporinase are the most widely observed mechanisms of resistance (respectively 22% and 9% of 649 strains). Prevalence of extended spectrum betalactamases was low (1%) and essentially observed for K. pneumoniae.

Anti-Bacterial Agents↗