ERP Micro December 2019

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

Correctly identified

Incorrectly identified

Total

Selective media no growth

Organism

MALDI Biotyper Reference MALDI Biotyper

Reference

MALDI Biotyper Reference

Citrobacter farmeri ATCC 51633 a Citrobacter freundii QL 11007.10 b Escherichia coli ATCC 10536

42 40 42 42 36 42 37 41

12 14 13 14 14 10 14 14

0 0 0 0 0 0 0 1 1

2 0 1 0 0 4 0 0 7

0 2 0 0 6 0 5 0

42 40 42 42 36 42 37 42

14 14 14 14 14 14 14 14

Hafnia alvei ATCC 51815

Klebsiella pneumoniae ATCC 10031 Pseudomonas aeruginosa ATCC 35032

Salmonella Hadar ATCC 51956 Serratia marcescens QL 11007.1

 Total isolates

322

105

13

323 c

112 d

a  ATCC = American Type Culture Collection biological materials resource (Manassas, VA, USA). b  QL = Q Laboratories Collection (Cincinnati, OH, USA). c  Total numbers represent isolates analyzed on the three recommended culture media: TSA, CCI, and ESIA. d  Reference method performed from TSA agar only.

( 3 )  Target cleaning procedure (conduct in a fume cabinet).— ( a ) Transfer the target into a suitable container, e.g., a 100 mm glass Petri dish, and pour in enough 70% aqueous ethanol (prepared as described above) to cover the target plate surface. ( b ) Incubate for 5 min at room temperature (20–25°C). ( c ) Remove the target plate and rinse thoroughly under running tap water. ( d ) Using a fiber-free cloth, clean the target plate thoroughly with 70% aqueous ethanol. ( e ) Rinse the target with tap water and wipe with a fiber-free cloth. ( f ) Transfer the MALDI target plate to a fume hood, cover the target plate with a layer of 80% aqueous trifluoroacetic acid (prepared as described above) by adding 100 μL with a pipet, and thoroughly wipe all target plate positions with a fiber-free cloth or gloved hand.

( g ) Rinse the target plate with HPLC grade water and wipe dry with a fiber-free cloth. ( h ) Let the target plate dry completely for at least 15 min at room temperature (20–25°C). ( i ) Store the clean target plate in the container provided. Cleaned targets plates can be stored before use in a dry place at room temperature (20–25°C) in the container provided. Avoid exposing cleaned target plates to potential contamination (e.g., dust) or corrosive atmospheres. Note : Do not place any adhesive labels on the target. Do not drop or scratch the target plate. ( b )  GdnHCl procedure.— Before each run, ensure that the target plate being used has been cleaned properly. Prepare the solutions required for cleaning targets as follows: ( 1 ) Preparation of 70% aqueous ethanol.— ( a ) To prepare 100 mL solution, measure 30 mL deionized water with a graduated cylinder. ( b ) Transfer the water into a beaker.

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

Correctly confirmed

Incorrectly confirmed

Total

Selective media no growth

Organism

MALDI Biotyper Reference MALDI Biotyper

Reference

MALDI Biotyper Reference

Citrobacter farmeri ATCC 51633 a Citrobacter freundii QL 11007.10 b Escherichia coli ATCC 10536

42 40 42 42 36 42 37 42

12 14 13 14 14 10 14 14

0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0

0 2 0 0 6 0 5 0

42 40 42 42 36 42 37 42

14 14 14 14 14 14 14 14

Hafnia alvei ATCC 51815

Klebsiella pneumoniae ATCC 10031 Pseudomonas aeruginosa ATCC 35032

Salmonella Hadar ATCC 51956 Serratia marcescens QL 11007.1

 Total isolates

323

105

13

323 c

112 d

a  ATCC = American Type Culture Collection biological materials resource (Manassas, VA, USA). b  QL = Q Laboratories Collection (Cincinnati, OH, USA). c  Total numbers represent isolates analyzed on the three recommended culture media: TSA, CCI, and ESIA. d  Reference method performed from TSA agar only.

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