TABLE 4.
Summary of data for smear-positive isolates classified according to species and processing method
| Species | Total no. of culturepositive AFB specimens | No. of specimens with smear result by decontamination methoda
|
||
|---|---|---|---|---|
| NALC/NaOH only | CB-18 only | Both methods | ||
| MTBC | 29 | 0 | 7 | 20 |
| MAC | 29 | 1 | 7 | 8 |
| M. kansasii | 5 | 0 | 0 | 5 |
| M. chelonae | 12 | 0 | 2 | 4 |
| M. fortuitum | 8 | 0 | 2 | 0 |
| M. gordonae | 8 | 0 | 0 | 0 |
| M. avium-M. intracellulareM. scrofulaceum | 3 | 0 | 0 | 0 |
| Other | 5 | 0 | 2 | 0 |
| Unknown | 3 | 0 | 2 | 0 |
| Lost | 4 | 0 | 1 | 0 |
| Total (no. smear positive and culture negative) | 106 | 1 (0) | 23 (14) | 37 (1) |
A specimen was considered smear positive if the smear value was 1+ or greater, independent of the culture results, or if a smear result was reported as ± by that method and the specimen could be confirmed by culture (solid or liquid media) by any processing method (either NALC/NaOH, CB-18, or both). See Materials and Methods for smear reporting criteria. The overall smear sensitivities were 35.8% for NALC/NaOH and 56.6% for CB-18 (P < 0.01). The overall smear specificities were 99.8% for NALC/NaOH and 96.8% for CB-18. The MTBC smear sensitivities were 69.0% for NALC/NaOH and 93.1% for CB-18 (P < 0.01). The MOTT smear sensitivities were 23.4% for NALC/NaOH and 42.9% for CB-18 (P < 0.01).