Sending instructions for Gram Negative Bacilli

1. Selection criteria

For Enterobacteriaceae:

• Suspicion of CPE: K.pneumoniae or E. coli with decreased susceptibility (intermediate or resistant) to meropenem or another carbapenem (e.g.: ertapenem) by local susceptibility testing method.
  Other species of Enterobacteriaceae should not be sent except in case of suspicion of outbreaks (more than one sporadic case).
• Suspicion of ESBL: strain cefotaxime,ceftriaxone and/or ceftazidime resistant.

For Pseudomonas and Acinetobacter spp:

• Strains with decreased susceptibility to imipenem and/or meropenem (not ertapenem which intrinsically lacks significant  activity against these two organisms)
• Strain resistant to all antibiotics

2. Sending of the strains

• Fresh (<24h) and pure culture subcultured from a single colony on a non-chromogenic, non-selective media and antibiotics-free media (including disk diffusion plates which should be avoided). Preferred culture on blood agar plate with individual colonies visualized and avoid use of agar tube.

• The completed isolate submission form and a copy of the susceptibility results performed locally must be attached to the strain, please correctly specify the address and the email address of the contact person from the referring laboratory.

• Please join the following submission form to your strain(s)

Request of characterization of resistance mechanisms :download “CPE _submission form"

Request of molecular typing :download “Typing _submission form"

• Strains can be sent at room temperature to the following address:

3. Unacceptable request

The NRC may reject the strain for analysis for the following reasons:

• Absence or incomplete submission forms
• Culture specimen without a copy of the susceptibility results or/and without identification reference
• Damaged sample (broken tubes, crushed agar plates)
• Contamination of the received culture specimen
• Misidentification (discrepancy between the identification provided on the isolate form and the identification obtained on the strain received)
• Duplicate bacterial isolate (same species, same susceptibility profil from several repeated sampling or several anatomical sites in the same patient)
• Bacterial isolate susceptible to all carbapenems
• Bacterial isolate confirmed CPE by commercial testing (antigen or molecular test) in your laboratory
• Bacterial isolate belonging to a species/genus other than Enterobacteriaceae, Pseudomonas spp.,Acinetobacter spp.

4. Communication of results

The NRC is committed to meeting the following deadlines:

• Within 3 working days after receipt of the strain for the temporary protocol containing the result of screening for carbapenemase production. The protocol is sent by email.
• Within 8 working days after receipt of the strain for the definitive protocol with the complete final results. The definitive protocol is sent by post.