ERP Micro December 2019

Table 2017.09C. Summary of results for the identification of Gram-negative organisms– Salmonella : Exclusivity

Incorrectly identified as Salmonella spp.

Correctly identified

Total

Other reference incorrectly identified

MALDI Biotyper not tested

Organism a

MALDI Biotyper Reference MALDI Biotyper Reference

MALDI Biotyper Reference

Providencia stuartii Ad1575 Citrobacter braakii Ad2701 Cronobacter sakazakii Ad1418 Yersinia enterocolitica A00C066 Aeromonas hydrophila Ad1570 Escherichia hermanii Ad457 Plesiomonas shigelloides Ad673 Serratia marcescens Ad447

45 45 45 44 42 45 44 45

15 12 15 14 14

0 0 0 0 0 0 0 0 0

0 3 0 0 0 0 0 0 3

0 0 0 1 1

0 0 0 1 3 0 1 0 5

45 45 45 44 42 45 44 45

15 15 15 15 15 15 15 15

5

10

15 15

0 0

 Total isolates

355

105

12

355 b

120 c

a  ADRIA Development Collection (Quimper, France). b  Total numbers represent isolates analyzed on the three recommended culture media: TSA, XLD, and RAPID’ Salmonella . c  Reference method performed from TSA agar only.

( a ) Microflex LT/SH MALDI-MS System (Cat. No. 8269956) or MALDI Biotyper Smart System (Cat. No. 1853665). ( b ) MBT Compass Library.— Version with 6903 MSPs or higher . Cat. No. 1829023.

(in the nanosecond range) between pulsed acceleration and the corresponding detector signal of the ions, and the time is converted into an exact molecular mass. The highly abundant microbial ribosomal proteins result in a mass spectrum with a characteristic mass and intensity distribution pattern. This pattern is species-specific for many bacteria, yeasts, and molds and can be used as a ‘molecular fingerprint’ to identify a test organism. The mass spectra are transformed into peak lists by the MALDI Biotyper software and are compared to the patterns in the reference library. B. Apparatus and Reagents Items ( a )–( j ) are available from Bruker Daltonik GmbH (Bremen, Germany).

( c ) MBT Compass software.— Cat. No. 1843241. ( d ) MBT Explorer module.— Cat. No. 1828476. ( e ) Barcode scanner .—Cat. No. 8268821 (optional).

( f ) Holder for barcode scanner.— Cat. No. 8276754 (optional). ( g ) MSP 96 target polished steel BC (Cat. No. 8280800), MSP 48 target polished steel BC (Cat. No. 8281817), or MBT Biotarget 96 (Cat. No. 1840375) with the MSP adapter MALDI Biotarget (Cat. No. 8267615). ( h ) α-Cyano-4 hydroxyinnamic acid (HCCA) matrix .—Portioned (Cat. No. 8255344) or MBT Galaxy HCCA Matrix GPR (Cat. No. 1823405).

Table 2017.09D. Summary of results for the confirmation of Gram-negative organisms– Salmonella : Exclusivity

Incorrectly confirmed as Salmonella spp.

Correctly confirmed

Total

MALDI Biotyper not tested

Organism a

MALDI Biotyper

Reference MALDI Biotyper

Reference

MALDI Biotyper

Reference

Providencia stuartii Ad1575 Citrobacter braakii Ad2701 Cronobacter sakazakii Ad1418 Yersinia enterocolitica A00C066 Aeromonas hydrophila Ad1570 Escherichia hermanii Ad457 Plesiomonas shigelloides Ad673 Serratia marcescens Ad447

45 45 45 44 42 45 44 45

15 12 15 15 15 15 15 15

0 0 0 0 0 0 0 0 0

0 3 0 0 0 0 0 0 3

0 0 0 1 3 0 1 0 5

45 45 45 44 42 45 44 45

15 15 15 15 15 15 15 15

 Total isolates

355

117 b

355 c

120 d

a  ADRIA Development Collection (Quimper, France). b  Isolates correctly confirmed as non- Salmonella (117) and isolates correctly identified (105). c  Total numbers represent isolates analyzed on the three recommended culture media: TSA, XLD, and RAPID’ Salmonella . d  Reference method performed from TSA agar only.

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