Table 3.
Sensitivity of the Urine Antigen Assay
| Species | n (%) B. dermatitidis | n (%) B. gilchristii | P value1 |
|---|---|---|---|
| True positives | 26 (72) | 31 (79) | |
| False negatives | 10 (28) | 7 (18) | |
| Unknown | 0 (0) | 1 (3) | |
| Total cases | 36 (100) | 39 (100) | |
| Study site | MCHS | UWHC | |
| True positives | 38 (75) | 19 (79) | |
| False negatives | 12 (24) | 5 (21) | |
| Unknown | 1 (2) | 0 (0) | |
| Total cases | 51 (100) | 24 (100) | |
| Disease location | Isolated pulmonary | Disseminated | |
| True positives | 43 (81) | 14 (64) | |
| False negatives | 9 (17) | 8 (36) | |
| Unknown | 1 (2) | 0 (0) | |
| Total cases | 53 (100) | 22 (100) | |
| Testing timeframe | ≤ 7 days post-diagnosis | > 7 days post-diagnosis | |
| True positives | 48 (83) | 9 (53) | |
| False negatives | 9 (16) | 8 (47) | 0.0071 |
| Unknown | 1 (2) | 0 (0) | |
| Total cases | 58 (100) | 17 (100) |
1
Fisher’s exact test (Yates correction) with significance defined as P ≤ 0.05.