Breastmilk donations: Bacteriological assessment, analysis of causes of non-compliance and suggestions for improvement.

A total of 1099 breastmilk donations received by the milk bank at the Amiens University Hospital from January to June 2016 were assessed for bacteriological contamination according to French regulations. This consisted in enumerating the total aerobic flora before and after heat treatment as well as the specific enumeration of coagulase-positive staphylococci. Results above the mandatory limits for at least one of these parameters were found in 25.9% of the donations, resulting in the destruction of approximately one-quarter of the volume of the donations (∼195L). This is a huge loss in both economic and health-related terms for neonates, especially for pre-terms. To identify ways to improve the bacteriological assessment results and reduce the percentage of discarded milk, an analysis of the causes was conducted. The two main causes of non-compliance were the detection of a cultivable aerobic flora after heat treatment and the presence of coagulase-positive staphylococci above the mandatory limit (11.7% and 11.2% of the tested donations, respectively). Bacillus spp. were the leading cause of post-heat-treatment non-compliance. Therefore, the implementation of better environmental control could help reduce this kind of contamination. As for samples harboring coagulase-positive staphylococci, a further detection of toxins using molecular biology techniques could help discriminate actual health-hazardous donations that have to be destroyed while enabling the use of toxin-negative donations. Nevertheless, the economic viability of this proposal needs to be further assessed because these techniques are costly. Finally, a change in breastmilk dilutions used to enumerate the total aerobic flora to better reflect the actual level of these bacteria in the milk was proposed. Indeed, the comparison of various combinations of milk dilutions led to the conclusion that the association of the 1/10 and 1/100 dilutions was the best compromise between technical ease of enumeration and ensuring the safety of the donations. Implementing these suggestions would help reduce the rate of non-compliance and give better access to safe breastmilk donations for neonates.

[A sensitive, specific and predictive isolation medium developed for Stenotrophomonas maltophilia study in healthcare settings]. / La mise au point d'un milieu sensible, spécifique et prédictif de recherche de Stenotrophomonas maltophilia dans l'environnement des soins.

BACKGROUND: Stenotrophomonas maltophilia (Smalto) is a prominent nosocomial pathogen, commonly isolated in the hospital environment. Multiple Smalto nosocomial outbreaks have been linked to contaminated water sources. This study aimed to develop a medium able to ease healthcare environment Smalto isolation. METHODS: Financed, from March 2007 to June 2008, by a university hospital of Amiens' clinical research program, this study allowed Stenotrophomonas maltophilia selective medium with coloured indicator (SM2i) development. SM2i is constituted of Mueller Hinton agar (MH), maltose, DL-methionine, bromothymol blue. The mixture sterilized is refreshed at 50 degrees C, its pH adjusted to 7.1, and render selective by addition of vancomycin, imipenem and amphotericin B. Then, SM2i agar is sunk into 90 cm diameter Petri dish dated and stored at 4 degrees C for 4 weeks. SM2i is developed using Pasteur Institute culture type collection (CIP) strains of Smalto, Burkholderia cepacia, Pseudomonas aeruginosa (Psa) and a Smalto strain of our hygiene laboratory collection. It was validate on Psa imipenem-resistant and Enterococcus faecium vancomycin-resistant strains, then, tested on cold water first jet and faucet cotton-swabs samples. SM2i tests were made in comparison with the MH agar, MH agar plus four paper disks loaded 10 microg of imipenem and Cetrimed agar. Its sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, accuracy, likehood-ratio (LR) and Youden index have been determined. RESULTS: SM2i agar is better in culturing Smalto test-strains. On SM2i, Smalto colonies are smooth, round, greeny, olive or lime green, have a green olive centre with a peripheral lighter or a dark green centre with an olive green suburb surrounded by a blue halo. SM2i is a selective, specific, predictive, accurate medium to search for Smalto in healthcare environment. In 122 pairs of cold water first jet and taps cotton-swabs samples, Smalto was isolated from 14.8% of water samples, 10.7% of cotton-swabs samples. It was isolated alone in 6.6% of water samples and 2.5% of swab samples. Thus, smalto has biocontaminated 17.2% of cold water taps. Compared to MH agar, SM2i sensitivity, specificity, PPV, NPV, accuracy, LR were 100, 100, 100, 100, 100% and infinity, and 87.5, 100, 100, 98.1, 98.4% and infinity for water and cotton-swabs samples respectively. CONCLUSION: SM2i is a selective, specific, predictive medium which can allow easily isolating and identifying accurately Smalto in environmental samples. Its evaluation on clinical samples is on going.

[Stenotrophomonas maltophilia and Pseudomonas aeruginosa water-associated microbiologic risk assessment in Amiens' University Hospital Centre]. / Evaluation des risques microbiologiques hydriques associés à Stenotrophomonas maltophilia et Pseudomonas aeruginosa au CHU d'Amiens.

BACKGROUND: Pseudomonas aeruginosa (Psa) and Stenotrophomonas maltophilia (Smalto) are major opportunistic waterborne pathogens causing hospital-acquired infections. This study aimed to assess the biocontamination level of cold water used in Amiens' university hospital wards, from March to June 2008. METHODS: We cultivated 122 pairs of cold water first jet and taps cotton-swabs on Cetrimide agar for Psa, on Stenotrophomonas maltophilia selective medium with coloured indicator (SM2i) for Smalto, on Mueller Hinton agar used as isolation medium reference for both, 48h at 30 degrees C. Data analysed with Epi-Info 6.04dFr were compared with chi(2) test, significant at p<.05. RESULTS: Psa and Smalto were isolated in 26.2 and 14.8% of water samples and in 21.3 and 10.7% of swab samples respectively. They were associated in 11.5% of water samples and 5% of swab samples. Psa was alone in 13.1% of water samples and 7.4% of swab samples whereas Smalto was found in 6.6% of water and 2.5% of swabs. Psa and Smalto were isolated from 14.8% of water samples and 8.2% of swab samples of the same tap. Finally, respectively 35.2 and 17.2% of the cold water taps were biocontaminated by Psa and Smalto. In fact, microbiologic water taps contamination risk was two-fold higher for Psa than for Smalto, p<.001, without variation between wards. CONCLUSION: Sm2i and Cetrimide are suited and efficient medium respectively for Smalto and Psa isolation. Cold-water samples are sufficient for waterborne pathogens biocontamination risk appraisal. Our results urged healthcare workers on efficient water fittings microbiologic risk control to prevent healthcare associated waterborne infections, notably due to Psa and Smalto.

[Extended-spectrum betalactamases producing Escherichia coli: a new health-care associated infection threat?]. / Escherichia coli producteurs de bêtalactamases à spectre étendu: de nouvelles menaces nosocomiales ?

OBJECTIVES: Study the health-care associated infection risk due to Extended-Spectrum Betalactamases Producing Escherichia coli (ESBL Esc) isolated from diagnostic samples. METHODS: Descriptive, longitudinal and prospective study of 104 diagnostic isolates of ESBL Esc, one per patient, identified in Amiens university hospital between February 1999 and December 2005. Patients (sex, age, contamination risk factor, antecedent hospitalization) and microbiological data were progressively collected, entered into EPI INFO 6.04dFr software (ENSP, France) database, and compared using the chi-square test and Wilcoxon rank sum test, as appropriate. A p value of less than 0.05 was considered significant. RESULTS: Diagnostic ESBL Esc isolates raised, per 1000 isolates of Esc, from 1.2 in 1999 to 6 in 2005. Global and acquired isolates number of ESBL Esc varied from 7 and 3 in 2002 to 25 and 19 in 2003 (P=0.22). ESBL Esc global and acquired incidence per 10(5) patient-days were, 0.8 and 0.6 in 1999 and 4.99 and 3.4 in 2005 (P<10(-6)), but rose from 0.6 acquired isolate in 2002 to 3.9 in 2003 (P=0.002). ESBL Esc, isolated from urines, stools, pulmonary, blood and surgical site samples of patients of>/=65 years aged (68.3%), were imipenem and latamoxef sensitive. Their acquisition risk factors found were hospitalization during the last 6 month period (40/104) and transfer from other institutions (20/104). CONCLUSION: ESBL Esc isolates, among ESBL-producing Enterobacteriaceae, constitute an escalating health-care associated risk in our institution. The research at admission time of ESBL-producing Enterobacteriaceae, mainly in acute geriatric wards, strict isolation precaution and hand hygiene observance, rational antibiotic usage, are the key actions to control their cross transmission. Nonetheless, other studies are needed to determine whether we are in front of an ESBL Esc new clone emergence.