TABLE 1.
Effect of syringing and sonication on the viable count and clumping of M. tuberculosisa
| Treatment | Batch 1
|
Batch 2
|
||||||
|---|---|---|---|---|---|---|---|---|
| Viable count (CFU/ml) | Clumping (%)
|
Viable count (CFU/ml) | Clumping (%)
|
|||||
| 1 or 2 | 2-10 | >10 | 1 or 2 | 2-10 | >10 | |||
| None | 2.6 × 107 | 30 | 45 | 25 | 4.3 × 107 | 55 | 34 | 11 |
| Syringed | 4.3 × 107 | 73 | 25 | 2 | 8.6 × 107 | 68 | 29 | 3 |
| Sonication | ||||||||
| Three 30-s bursts | 6.0 × 107 | 90 | 9 | 1 | 9.2 × 107 | 85 | 15 | 0 |
| 5 min | 3.9 × 106 | 97 | 2 | 1 | 1.0 × 107 | 79 | 14 | 7 |
a
Two batches of M. tuberculosis were suspended in binding medium and left untreated, syringed 10 times through a 25 gauge needle, or sonicated. The numbers of viable CFU were assessed for each sample. In addition, smears of each sample were fixed and stained, and clumping was assessed microscopically.