Table 2.

Comparison of total cost to result for 927 clinical bacterial isolates^a

Organism group	No. of isolates	Cost (AUD$)		Cost savings per group (AUD$)
		Current method	Using MALDI-TOF MSb
Anaerobes	12	126.00	5.40	120.60
Enterobacteriaceae	298	3,314.64	1,010.78c	2,303.86
Gram-positive rods	33	833.91	344.85d	489.06
Gram-positive cocci	429	3,714.21	527.56e	3,186.65
Miscellaneous gram-negatives	78	1,471.82	35.10	1,436.72
Non-fermentative gram-negative rods	77	893.43	34.65	858.78
Total	927	10,354.01	1,958.34	8,395.67

^aIncludes reagent and labor costs based upon one identification attempt per isolate.

^bOnly six isolates required crude extraction to provide an acceptable identification. This added an additional AUD$2.70 to the total cost of the MALDI-TOF identifications.

^cIncludes the cost of conventional identification methods (including serological confirmation) for 28 isolates that could not be identified by MALDI-TOF MS.

^dIncludes the cost for the identification of three isolates by 16S rRNA analysis.

^eIncludes the cost for additional identification methods such as optochin susceptibility for 38 isolates.