[Stenotrophomonas maltophilia and Pseudomonas aeruginosa water-associated microbiologic risk assessment in Amiens' University Hospital Centre].
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.


CONCLUSIONS
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.
Adjidé
C C
CC
Unité d'hygiène et épidémiologie hospitalière, service d'épidémiologie hygiène hospitalière et santé publique, CHU d'Amiens, 1, place Victor-Pauchet, 80054 Amiens cedex 01, France. crespin.adjide@chu-amiens.fr
De Meyer
A
A
Weyer
M
M
Obin
O
O
Lamory
F
F
Lesueur
C
C
Trouillet
L
L
Biendo
M
M
Eb
F
F
Ganry
O
O
D001431:Bacteriological Techniques; D003428:Cross Infection / Q000517:prevention & control; D003470:Culture Media; D004866:Equipment Contamination; D005602:France; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000517:prevention & control*; D006785:Hospitals, University; D006801:Humans; D010362:Patients' Rooms; D011552:Pseudomonas Infections / Q000453:epidemiology / Q000517:prevention & control*; D011550:Pseudomonas aeruginosa / Q000254:growth & development / Q000302:isolation & purification*; D018570:Risk Assessment; D017751:Safety Management; D012498:Sanitary Engineering / Q000295:instrumentation; D020615:Stenotrophomonas maltophilia / Q000254:growth & development / Q000302:isolation & purification*; D014871:Water Microbiology; D014876:Water Pollution; D014881:Water Supply
D003470:Culture Media