Table 3.
Sensitivity, specificity, and accuracy values associated with different skin layers and real-time polymerase chain reaction thresholds.
| Threshold | Sample | Multibacillary | Paucibacillary | ||||
|---|---|---|---|---|---|---|---|
| Sensitivity—positive/leprosy (95%CI) | Specificity—negative/control (95%CI) | Accuracy (95%CI) | Sensitivity—positive/leprosy (95%CI) | Specificity—negative/control (95%CI) | Accuracy (95%CI) | ||
| Any bacillus threshold | Epidermis | 81.82% – 18/22 (61.48, 92.69) | 76.09% – 35/46 (62.06, 86.09) | 77.94% (66.74, 86.15) | 40.63% - 13/32 (25.52, 57.74) | 76.09% – 35/46 (62.06, 86.09) | 61.54% (50.44, 71.55) |
| Upper dermis | 90.91% – 20/22 (72.18, 97.47) | 73.91% – 34/46 (59.74, 84.4) | 79.41% (68.36, 87.32) | 37.50% – 12/32 (22.93, 54.75) | 73.91% – 34/46 (59.74, 84.4) | 58.97% (47.89, 69.22) | |
| Inferior dermis | 90.48% – 19/21 (71.09, 97.35) | 77.27% – 34/44 (63.01, 87.16) | 81.54% (70.45, 89.11) | 37.50% – 12/32 (22.93, 54.75) | 77.27% – 34/44 (63.01, 87.16) | 60.53% (49.29, 70.75) | |
| Hypodermis | 80% – 16/20 (58.4, 91.93) | 83.72% – 36/43 (70.03, 91.88) | 79.25% (66.54, 88) | 38.71% – 12/31 (23.73, 56.18) | 83.72% – 36/43 (70.03, 91.88) | 64.86% (53.5, 74.76) | |
| Nasal swab | 36.84% – 7/19 (19.15, 58.96) | 100% – 28/28 (87.94, 100) | 74.47% (60.49, 84.75) | 10.34% – 3/29 (3.581, 26.39) | 100% – 28/28 (87.94, 100) | 54.39% (41.59, 66.63) | |
| 0.1 bacillus threshold | Epidermis | 68.18% – 15/22 (47.32, 83.64) | 89.13% – 41/46 (76.96, 95.27) | 82.35% (71.64, 89.61) | 18.75% – 6/32 (8.889, 35.31) | 89.13% – 41/46 (76.96, 95.27) | 60.26% (49.16, 70.39) |
| Upper dermis | 72.73% – 16/22 (51.85, 86.85) | 86.96% – 40/46 (74.33, 93.88) | 82.35% (71.64, 89.61) | 18.75% – 6/32 (8.889, 35.31) | 86.96% – 40/46 (74.33, 93.88) | 58.97% (47.89, 69.22) | |
| Inferior dermis | 80.95% – 17/21 (60, 92.33) | 84.09% – 37/44 (70.63, 92.07) | 83.08% (72.18, 90.28) | 28.13% – 9/32 (15.56, 45.37) | 84.09% – 37/44 (70.63, 92.07) | 60.53% (49.29, 70.75) | |
| Hypodermis | 80% – 16/20 (58.4, 91.931) | 93.02% – 40/43 (81.39, 97.6) | 88.89% (78.8, 94.51) | 16.13% – 5/31 (7.093, 32.63) | 93.02% – 40/43 (81.39, 97.6) | 60.81% (49.42, 71.14) | |
| Nasal swab | 21.05% – 4/19 (8.508, 43.33) | 100% – 28/28 (87.94, 100) | 68.09% (53.83, 79.6) | 0.0% – 0/29 (0.0, 11.7) | 100% – 28/28 (87.94, 100) | 49.12% (36.62, 61.74) | |
| 1 bacillus threshold | Epidermis | 45.45% – 10/22 (26.92, 65.34) | 100% – 46/46 (92.29, 100) | 82.35% (71.64, 89.61) | 9.375% – 3/32 (3.24, 24.22) | 100% – 46/46 (92.29, 100) | 62.82% (51.73, 72.71) |
| Upper dermis | 68.18% – 15/22 (47.32, 83.64) | 93.48% – 43/46 (82.5, 97.76) | 85.29% (75, 91.81) | 9.375% – 3/32 (3.24, 24.22) | 93.48% – 43/46 (82.5, 97.76) | 58.97% (47.89, 69.22) | |
| Inferior dermis | 66.67% – 14/21 (45.37, 82.81) | 95.45% – 42/44 (84.86, 98.74) | 86.15% (75.73, 92.54) | 6.25% – 2/32 (1.731, 20.15) | 95.45% – 42/44 (84.86, 98.74) | 57.89% (46.68, 68.35) | |
| Hypodermis | 60% – 12/20 (38.66, 78.12) | 97.67% – 42/43 (87.94, 99.59) | 85.71% (75.03, 92.3) | 9.677% – 3/31 (3.346, 24.9) | 97.67% – 42/43 (87.94, 99.59) | 60.81% (49.42, 71.14) | |
| Nasal swab | 15.79% – 3/19 (5.52, 37.57) | 100% – 28/28 (87.94, 100) | 65.96% (51.67, 77.83) | 0.0% – 0/29 (0.0, 11.7) | 100% – 28/28 (87.94, 100) | 49.12% (36.62, 61.74) | |
Analysis performed in the subgroups of paucibacillary and multibacillary patients according to the Ridley and Jopling classification.