TABLE 7.
Comparison of culture results according to smear result and mycobacterial group
| AFB type | Smear categorya | Total no. of culture-positive AFB specimens | No. of specimens with culture result by decontamination methodb
|
||
|---|---|---|---|---|---|
| NALC/NaOH only | CB-18 only | Both methods | |||
| MTBC | Positive | 27 | 3 | 0 | 24 |
| Negative | 2 | 1 | 1 | 0 | |
| Total | 29 | 4 | 1 | 24 | |
| MOTT | Positive | 34 | 2 | 9 | 23 |
| Negative | 43 | 7 | 31 | 5 | |
| Total | 77 | 9 | 40 | 28 | |
A specimen was considered smear positive if it was reported as positive when processed by either the NALC/NaOH method, the CB-18 method, or both processing methods.
The culture sensitivities among all smear-positive specimens were 85.2% for NALC/NaOH and 91.8% for CB-18 (P > 0.05). The culture sensitivities among all smear-negative specimens were 28.9% for NALC/NaOH and 82.2% for CB-18 (P < 0.01). The culture sensitivities among smear-positive MTBC specimens were 100% for NALC/NaOH and 88.9% for CB-18 (P > 0.05). The culture sensitivities among smear-negative MTBC specimens were 50.0% for NALC/NaOH and 50.0% for CB-18 (P > 0.05). The culture sensitivities among smear-positive MOTT specimens were 73.5% for NALC/NaOH and 94.1% for CB-18 (P < 0.05). The culture sensitivities among smear-negative MOTT specimens were 27.9% for NALC/NaOH and 83.7% for CB-18 (P < 0.01).