Reaction medium for methicillin-resistant Staphylococcus aureus (MRSA) bacteria

• US 8,415,115 B2
• Filed: 10/07/2009
• Issued: 04/09/2013
• Est. Priority Date: 10/08/2008
• Status: Active Grant

• Current Assignee: Biomerieux B.V. (Compagnie Merieux Alliance SAS)
• Original Assignee: Biomerieux B.V. (Compagnie Merieux Alliance SAS)
• Inventors: Orenga, Sylvain, Robichon, Denis, Zambardi, Gilles
• Primary Examiner(s): Hanley, Susan
• Assistant Examiner(s): NGUYEN, NGHI V
• Application Number:
  US13/062,768
• Publication Number:
  US 20110165604A1
• Time in Patent Office: 1,280 Days
• Field of Search: 435/18, 435/36
• US Class Current: 435/18
• CPC Class Codes: C12Q 1/045 Culture media therefor
• CPC Class Codes: C12Q 1/14 Streptococcus; Staphylococcus

Abstract

A reaction medium for detecting and/or identifying Methicillin-resistant Staphylococcus aureus (MRSA) bacteria, comprising a predetermined combination of two antibiotics, a first antibiotic which belongs to the cephalosporin family and a second antibiotic, said first and second antibiotics each being at a sub-inhibitory concentration.

Claims

1. A reaction medium for detecting and/or identifying Methicillin-resistant Staphylococcus aureus (MRSA) bacteria, comprising

a) a predetermined combination of two antibiotics, a first antibiotic which belongs to the cephalosporin family and a second antibiotic, wherein said first and second antibiotics are each at a sub-inhibitory concentration for Methicillin-sensitive Staphylococcus aureus (MSSA);

and

b) a substrate for detecting an enzymatic or metabolic activity of said MRSA.

2. The reaction medium according to claim 1, wherein said first antibiotic belongs to the cephamycin subfamily.

3. The reaction medium according to claim 1, wherein said second antibiotic belongs to the carbapenem family.

4. The reaction medium according to claim 1, wherein said second antibiotic belongs to the cephalosporin family.

5. The reaction medium according to claim 1, wherein said substrate is for detecting a glycosidase, esterase or peptidase enzymatic activity.

6. The reaction medium according to claim 5, wherein said substrate is for detecting an alpha-glucosidase enzymatic activity.

7. The reaction medium according to claim 1, wherein said substrate is for detecting carbohydrate metabolic activity.

8. The reaction medium according to claim 1, further comprising a second substrate for detecting an enzymatic or metabolic activity.

9. The reaction medium according to claim 8, wherein said second substrate is for detecting an alpha-glucosidase enzymatic activity.

10. The reaction medium according to claim 4, wherein said first and/or second antibiotic(s) belonging to the cephalosporin family is selected from:

a first-generation cephalosporin;

a second-generation cephalosporin;

a third-generation cephalosporin; and

a fourth-generation cephalosporin.

11. The reaction medium according to claim 3, wherein said second antibiotic belonging to the carbapenem family is selected from Meropenem, Ertapenem and Imipenem.

12. The reaction medium according to claim 1, wherein the combination of two antibiotics is a) Cefoxitin and Cefotaxime;

or b) Cefoxitin and Ertapenem.

13. A method for detecting and/or identifying Methicillin-resistant Staphylococcus aureus (MRSA) bacteria, in a biological sample, comprising:

a) inoculating the biological sample on a reaction medium according to claim 1;

b) incubating the biological sample; and

c) identifying colonies on the reaction medium as being MRSA colonies when MRSA bacteria is present in the biological sample.