Table 4. Validated alarms emitted by MARSS and investigations from May 21, 2013, through June 4, 2014, Marseille, France*.
| Pathogen | Alarm date | Abnormal event observed | Investigation | Result | Intervention |
|---|---|---|---|---|---|
| Klebsiella pneumoniae | 2013 Jul 9 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| K. pneumoniae | 2013 Jul 30 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| K. pneumoniae | 2013 Aug 20 | Abnormal increase in no. strains with ESBLphenotype | Additional investigations led to conclusion that increase was due to a technical problem in MARSS | False alarm | Technical problem was immediately corrected |
| K. pneumoniae | 2013 Sep 9 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| Salmonella spp. | 2013 Sep 10 | 3 strains isolated from 3 patients | Additional investigations did not identify any links between infected patients | False alarm | No intervention |
| K. pneumoniae | 2013 Sep 10 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| Citrobacter koseri | 2013 Sep 17 | Various strains isolated with same antibiotic-resistance profile | Additional investigations did not identify any links between infected patients | False alarm | No intervention |
| Enterobacter cloacae | 2013 Sep 20 | Isolation from 1 patient of E. cloacae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| K. pneumoniae | 2013 Sep 24 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| Enterobacter aerogenes | 2013 Oct 4 | Isolation from 1 patient of E. aerogenes strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| Staphylococcus epidermidis | 2013 Oct 8 | Abnormal increase in no. S. epidermidis strains highly resistant to methicillin | Additional investigations did not identify any links between infected patients, and no clones were identified with MALDI-TOF spectra analysis | False alarm | No intervention |
| Salmonella spp. | 2013 Oct 8 | Abnormal increase in no. strains isolated from patients hospitalized in same hospital | Additional investigations did not identify any links between infected patients, and no clones were identified by MALDI-TOF spectra analysis | False alarm | No intervention |
| K. pneumoniae | 2013 Oct 15 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| K. pneumoniae | 2013 Oct 15 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| K. pneumoniae | 2013 Nov 22 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| K. pneumoniae | 2013 Dec 10 | Abnormal increase in no. strains with ESBL resistance phenotype | Additional investigations did not identify any links between infected patients, and no clones were identified by MALDI-TOF spectra analysis | False alarm | No intervention |
| K. pneumoniae | 2013 Jan 3 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and report sent to ARS |
| E. cloacae | 2014 Jan 7 | Abnormal increase in no. E. cloacae strains with wild resistance phenotype isolated for week of 2013 Nov 25p[ | Additional investigations did not identify any links between infected patients, and no clones were identified by MALDI-TOF spectra analysis | False alarm | No intervention |
| Morganella morganii | 2014 Jan 7 | Abnormal increase in no. M. morganii strains isolated with inhibitor-resistant penicillinase phenotype | Additional investigation allowed us to conclude it was a wild phenotype strain | False alarm | No intervention |
| Pseudomonas aeruginosa | 2014 Jan 7 | Abnormal increase in no. P. aeruginosa strains with wild-type resistance phenotype isolated for 28/10/2013 week | Additional investigations did not identify any links between infected patients, and no clones were identified by MALDI-TOF spectra analysis | False alarm | No intervention |
| K. pneumoniae | 2014 Jan 21 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| Proteus mirabilis | 2014 Jan 25 | Isolation from 1 patient of P. mirabilis strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing did not confirm that strain was carbapenemase producing | False alarm | No intervention |
| Enterobacter aerogenes | 2014 Apr 8 | Abnormal increase in no. strains with high level cephalosporinase resistance phenotype | Additional investigations did not identify any links between infected patients, and no clones were identified with MALDI-TOF spectra analysis | False alarm | No intervention |
| Escherichia coli | 2014 Apr 8 | Abnormal increase in no. strains with inhibitor-resistant penicillinase phenotype | Additional investigations did not identify any links between infected patients, and no clones were identified with MALDI-TOF spectra analysis | False alarm | No intervention |
| P. mirabilis | 2014 Apr 8 | Abnormal increase in no. strains with wild phenotype | Additional investigations did not identify infected patients, and no clones were identified with MALDI-TOF spectra analysis | False alarm | No intervention |
| Streptococcus agalactiae | 2014 Apr 8 | Abnormal increase in no. strains with methicillin-resistant phenotype | Additional investigations did not identify any links between infected patients, and no clones were identified with MALDI-TOF spectra analysis | False alarm | No intervention |
| E. coli | 2014 Apr 8 | Abnormal increase in no. strains with inhibitor-resistant phenotype | Additional MALDI-TOF spectra analysis did not identify clones | True alarm | No explanations were found. First results from ongoing investigations show that most infections come from community-acquired urinary tract infections in women |
| E. cloacae | 2014 Apr 8 | Isolation from 1 patient of E. cloacae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| K. pneumoniae | 2014 May 21 | Isolation from 1 patient of K. pneumoniae strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
| Serratia marcescens | 2014 Jun 3 | Isolation from 1 patient of S. marcescens strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing did not confirm that strain was carbapenemase producing | False alarm | No intervention |
| P. mirabilis | 2014 Jun 4 | Isolation from 1 patient of P. mirabilis strain that seemed to produce carbapenemases | Additional antibiotic susceptibility testing confirmed that strain was carbapenemase producing | True alarm | Patient isolated and resport sent to ARS |
*MARSS, Marseille Antibiotic Resistance Surveillance System; ESBL, extended spectrum β-lactamase;ARS, MALDI-TOF, matrix-assisted laser desorption ionization time of flight; ARS, Agence Régionale de Santé.