Table 3.
Mean score and standard deviation of MALDI-TOF MS analysis of Gram-positive isolates using four direct-smear methods
| Organism | No. of isolates | Direct-smear typea |
|||
|---|---|---|---|---|---|
| Heavy | Light | H+FA | L+FA | ||
| Overall | 239 | 2.096 (0.188) | 2.124 (0.186) | 2.204 (0.193)b | 2.110 (0.269) |
| Streptococcus spp. | 81 | 2.100 (0.200) | 2.150 (0.164) | 2.234 (0.180) | 2.100 (0.194) |
| Staphylococcus spp. | 69 | 2.104 (0.138) | 2.111 (0.142) | 2.195 (0.173) | 2.107 (0.187) |
| Enterococcus spp. | 24 | 2.131 (0.272) | 2.177 (0.313) | 2.303 (0.228) | 2.254 (0.263) |
| Bacillus spp. | 12 | 2.015 (0.080) | 1.990 (0.159) | 2.056 (0.204) | 2.019 (0.320) |
| Corynebacterium spp. | 20 | 2.137 (0.212) | 2.167 (0.191) | 2.217 (0.200) | 2.202 (0.213) |
| Miscellaneous Gram-positive rods | 23 | 1.980 (0.164) | 2.020 (0.166) | 2.084 (0.169) | 1.953 (0.216) |
| Miscellaneous Gram-positive cocci | 10 | 2.037 (0.166) | 2.117 (0.134) | 2.135 (0.205) | 2.091 (0.217) |
a
Data are presented as the means ± SD.
b
H+FA achieved the highest overall score, which was statistically higher than all other direct-smear methods (P < 0.0001).