Pseudomonas aeruginosa outbreak linked to mineral water bottles in a neonatal intensive care unit: fast typing by use of high-resolution melting analysis of a variable-number tandem-repeat locus.

Pseudomonas aeruginosa is an opportunistic pathogen that causes nosocomial infections in intensive care units. Determining a system of typing that is discriminatory is essential for epidemiological surveillance of P. aeruginosa. We developed a method for the typing of Pseudomonas aeruginosa, namely, multiple-locus variable-number tandem-repeat (VNTR) typing with high-resolution melting analysis (HRMA). The technology was used to genotype a collection of 43 environmental and clinical strains isolated during an outbreak in a neonatal intensive care unit (NICU) that we report. Nineteen strains isolated in other departments or outside the hospital were also tested. The genetic diversity of this collection was determined using VNTR-HRMA, with amplified fragment length polymorphism (AFLP) analysis as a reference. Twenty-five and 28 genotypes were identified, respectively, and both techniques produced congruent data. VNTR-HRMA established clonal relationships between the strains of P. aeruginosa isolated during the outbreak in the NICU and proved, for the first time, the role of mineral water as the inoculum source. VNTR typing with one primer pair in association with HRMA is highly reproducible and discriminative, easily portable among laboratories, fast, and inexpensive, and it demonstrated excellent typeability in this study. VNTR-HRMA represents a promising tool for the molecular surveillance of P. aeruginosa and perhaps for molecular epidemiologic analysis of other hospital infections.

[Pseudomonas aeruginosa infections in a neonatal care unit at Reunion Island]. / Infections nosocomiales à Pseudomonas aeruginosa en néonatalogie à l'île de la Réunion.

OBJECTIVE: To investigate an outbreak of Pseudomonas aeruginosa (PA) hospital-acquired infections in neonates. METHODS: Incidences were assessed retrospectively in the neonatal care units of the Groupe Hospitalier Sud-Réunion, from January 2003 to September 2005. Environmental survey, audit of health care workers and case-control study were performed to reinforce staff training and to determine risk factors. RESULTS: Of 1432 neonates, 40 were infected (median gestational age: 29 weeks, median birth weight: 1195 g), accounting for an attack rate of 2.8%. Between January 2003 and January 2004, incidence rates were less than 2 infections per 1000 hospitalisation days. In the last trimester of year 2004, the incidence rose to 5.6 infections per 1000 hospitalisation days and PA was found in all ocular swabs, leading to diagnose an epidemic. However, it was only 3 months later, after 3 new deaths of very preterm neonates, that the implementation of control measures and an audit of health care practices focused on water utilisation ruled out the outbreak. The overall fatality rate was 25%, and of 71% in severe diseases (septicemia or pneumonia). The epidemic pattern argued for a common unique source. Two risk factors were identified by logistic regression: exposure to mechanical ventilation beyond 4 days (OR 3.3; CI 95%: 1.3-8.4) and very preterm birth (OR 2.7; CI 95%: 1.0-7.7). CONCLUSION: Our findings highlight the need for a close collaboration between neonatologists and hygienists to improve health care practices and surveillance.

[Antimicrobial resistance of Streptococcus pneumoniae strains isolated in the Reunion Island during 2004]. / Résistance aux antibiotiques de Streptococcus pneumoniae à la Réunion en 2004.

OBJECTIVE AND METHOD: Available data from the Southern Reunion Island Medical Group was processed to assess the evolution of Streptococcus pneumoniae resistance to antibiotics since 1994 when the first penicillin-non-susceptible S. pneumoniae (PNSSP) was identified. In addition, 249 strains, isolated between 1998 and 2004, were tested against telithromycin and moxifloxacin. RESULTS: Between 1994 and 2004, the percentage of PNSSP increased from 0 to 59.2%. Among PNSSP, 13.9% were resistant strains in 2004 with MICs<4 microg/ml. Before 2001 the rate of resistance to penicillin was superior to 50%. In 2004, 15.8 and 8.7% of the isolated strains were of decreased susceptibility to amoxicillin and cefotaxime respectively while none were resistant to either treatment. Other antibiotics followed the pattern of resistance to penicillin. Between 1998 and 2004, resistance to erythromycin decreased from 42.5 to 35.1%, from 35.1 to 22.8% for cyclins, from 18.8 to 8.8 for chloramphenicol, and from 38.3 to 12.3% for cotrimoxazole. All tested strains were susceptible to both telithromycin and moxifloxacin. CONCLUSION: Amoxicillin remains efficient for all strains isolated in the Reunion Island in 2004. The presence of strains with decreased susceptibility to third generation cephalosporins implies combination with vancomycin for empirical treatment of pneumococcal meningitis. Moxifloxacin can be used when using a fluoroquinolone is justified. Telithromycin is efficient even on strains resistant to erythromycin and consequently this molecule can be prescribed in the case of a required macrolide treatment.

[Bacteriological and epidemiological data on Streptococcus pneumoniae in the hospital of southern Reunion Island]. / Données bactériologiques et épidémiologiques pour Streptococcus pneumoniae à l'hôpital Sud de La Réunion.

We studied the epidemiology of Streptococcus pneumoniae in southern Reunion Island from 1993 to 1998. Data were collected from the Centre hospitalier Sud Reunion. Incidence of pneumonia was calculated by applying published ratios to two different types of data (bacteriological, clinical). Survey of pneumococci showed that antimicrobial resistance of S. pneumoniae to penicillin G appeared in 1994 and reached high levels in 1998. We confirmed the increase of multiresistant strains among penicillin resistant S. pneumoniae. Serotyping the penicillin resistant S. pneumoniae has shown that these strains belonged to serogroups 9, 14, 19, 23. The MIC determined in PRP showed that imipenem was the most active agent among beta-lactamin antibiotics followed by ceftriaxone. Strains with high resistance to amoxicillin are rare. Annual incidence of meningitis was almost 0.4 per 100,000 inhabitants. Estimation of pneumonia incidence was between 44 and 78 per 100,000 inhabitants. Incidence in Reunion Island is twice to three times lower than the incidence in France. Death rate from pneumoniae (10%) is similar to that in France. In the course of the study, the number of isolated S. pneumoniae increased. Changing socio-economic conditions are probably associated with the emergence of PRP since 1994 and the increase in numbers of infections. Pneumococcal infections in Reunion Island are becoming a public health problem of the same importance as in France.

[Seasonal trends of respiratory syncytial virus infections on Réunion Island gathering data among hospitalized children]. / Répartition saisonnière des infections dues au virus respiratoire syncytial à l'île de La Réunion à partir de données recueillies auprès d'enfants hospitalisés.

Little is known about the epidemiology of respiratory syncytial virus (RSV) infections in tropical countries and in particular in tropical islands of the Indian Ocean. Our study reviewed all cases of RSV infections diagnosed among hospitalized children in the Hospital de Saint Pierre de la Réunion, from January 1993 to December 1999. 849 cases were identified of which 67.7% were infants under 6 months old. Most cases occurred from December to May (89% of all cases), showing a significant correlation with the hot and rainy season. These data confirm the previous studies and support the existence of seasonal trends of RSV infections in the tropics.

[Antibiotic resistance of Helicobacter pylori in Reunion Island: therapeutic consequences]. / Résistance aux antibiotiques de Helicobacter pylori à l'île de La Réunion: conséquences thérapeutiques.

The aims of this paper were to assess resistance of Helicobacter pylori to antibiotics included in the so-called French triple regimens and to identify the possible causes of therapeutic failure in Reunion island. Antibiotic resistance was determined for 109 strains. All the strains were sensitive to amoxicillin and tetracycline, 93.6% were sensitive to ciprofloxacin, 92.7% to erythromycin and 60.6% to metronidazole. Fifty three patients who had previously tested positive for H. pylori received for one week regimen of amoxicillin (1 g bd), clarithromycin (0.5 g bd) and omeprazole (20 mg bd). Eradication rate after therapy was of 73.6%. Therapeutic failure was analysed for 9 patients using random amplified polymorphic DNA and the presence or not of antibiotic resistance. One cause of failure is clarithromycin resistance. These data show that triple therapy can be used in Reunion Island. In case of failure, sensitivity must be detected because the rate of resistance to metronidazole is over 30%.

[Evolution of resistance to antibiotics from 1997 to 2005 in the Reunion Island]. / Évolution de la résistance aux antibiotiques de 1997 à 2005 à la Réunion.

OBJECTIVE: The groupe hospitalier Sud Reunion (GHSR) is a 1130-bed hospital center, located on the Reunion Island, (Indian Ocean). We studied the profiles of antibiotic resistance in 2005, and compared those with previous data collected in 1997-1998, and with Metropolitan France and European data. MATERIAL AND METHODOLOGY: All bacteriological strains isolated from diagnostic samples in 2005 were analyzed according to CA-SFM recommendations. RESULTS: Since 1997, the rates of resistance to enterobacteria (betalactam, aminoside, quinolone, trimethoprim-sulfamethoxazole), Pseudomonas aeruginosa (ticarcillin, amikacin, ciprofloxacin, fosfomycin), Acinetobacter baumanii (amikacin) has decreased significantly. The rate of methicillin-resistant Staphylococcus aureus (1997: 3.6 %, 2005: 13.4 %) has increased but less than in Metropolitan France. The rate of Streptococcuspneumonia with decreased susceptibility to penicillin has increased (1997: 25.5 %, 2005: 42.9 %), as for Haemophilusinfluenzae which present an important increase of betalactam resistance (1997: 15.5 %, 2005: 37.8 %). CONCLUSION: By comparing our data to 1997 and Metropolitan French data, it seems that the GHSR has managed to protect its hospital-based microbial ecology. However, community germs showed increasing resistance, probably because of an increasing antibiotic pressure, but with resistance rates often inferior to Metropolitan French ones.

Use of enzyme-linked immunosorbent assay and enzyme-linked immunoelectrotransfer blot for the diagnosis and monitoring of neurocysticercosis.

A total of 70 proven cases of neurocysticercosis from la Réunion (Indian Ocean) were studied with enzyme-linked immunoassay (ELISA) and immunoelectrotransfer blot (EITB) to detect specific antibodies in serum and cerebrospinal fluid (CSF). Absorbance levels of antibody to crude Taenia solium cyst extract as an antigen were compared with EITB banding-pattern and computed tomography-scan results. The EITB analysis of sera and CSF from patients with active neurocysticercosis, confirmed with characteristic brain-scan imaging and highest ELISA absorbance, regularly revealed two bands with molecular weights of 13 and 14 kDa, respectively. These low-molecular-weight fractions are potential markers of active cerebral cysticercosis, a result obtained in the simple epidemiological situation of La Réunion (Indian Ocean). A parallel study is underway in Madagascar, where cross-reactivities with other parasitic diseases, including Schistosoma infections, may interfere.

[Value of immunodiagnosis by ELISA and Western blotting for the diagnostic and therapeutic management of neurocysticercosis]. / Intérêt du diagnostic immunologique par ELISA et EITB pour la conduite diagnostique et therapeutique d'une neurocysticercose.

The humoral immune response in neurocysticercosis was studied in seventy patients from the Reunion Island (Indian Ocean). In the serum and the cerebrospinal fluid, specific antibodies were quantified using an enzyme-linked (ELISA) and Western-blot (EITB) technique. It was found that two antigenic fractions, of 13 and 14kd molecular weight, are highly specific of an active disease, for which the treatment is recommended. This new result, established in the quite simple epidemiologic environment of the Reunion island, is under validation in Madagascar.