TABLE 3.
Clinical sensitivity and specificity of the PCR assays for the detection of enteric pathogens
| Organism | Stool type | No. of strains/total no. of strains (%) |
Pf | |
|---|---|---|---|---|
| Sensitivity | Specificity | |||
| C. jejuni/C. colia | Any stool type | 49/51 (96) | 336/341 (99) | 0.26 |
| Fresh stool | 23/23 (100) | 266/270 (99) | 0.05 | |
| Cary Blair stool | 26/28 (93) | 70/71 (99) | 0.56 | |
| Salmonella spp. (HE)b | Any stool type | 34/34 (100) | 355/358 (99) | 0.08 |
| Fresh stool | 12/12 (100) | 281/281 (100) | 1.00 | |
| Cary Blair stool | 22/22 (100) | 74/77 (96) | 0.08 | |
| Salmonella spp. (SE+HE)c | Any stool type | 37/42 (88) | 350/350 (100) | 0.03 |
| Fresh stool | 12/17 (71) | 276/276 (100) | 0.03 | |
| Cary Blair stool | 25/25 (100) | 74/74 (100) | 1.00 | |
| Shigella spp.d | Any stool type | 6/6 (100) | 386/386 (100) | 1.00 |
| Fresh stool | 5/5 (100) | 288/288 (100) | 1.00 | |
| Cary Blair stool | 1/1 (100) | 98/98 (100) | 1.00 | |
| Yersinia spp.e | Any stool type | 4/5 (80) | 387/387 (100) | 0.32 |
| Fresh stool | 1/2 (50) | 291/291 (100) | 0.32 | |
| Cary Blair stool | 3/3 (100) | 96/96 (100) | 1.00 | |
C. jejuni(n = 49) and C. coli(n = 2).
HE, direct culture to Hektoen enteric agar.
Salmonella enterica serovars Typhimurium(n = 11), II 2:b:enxz15(n = 1), I 6,8:NM(n = 1), I 45:b:minus(n = 1), Hadar(n = 1), Montevideo(n = 2), Enteritidis(n = 5), II 58:Iz13z28:26(n = 1), Litchfield (n = 1), Hartford(n = 1), Nigeria(n = 2), Muenchen(n = 1), Agona(n = 1), I 4,5,12:i:(n = 1), Saintpaul(n = 1), Anatum(n = 2), Reading(n = 1), and unknown(n = 8). SE+HE, selenite enrichment and subculture to HE agar.
S. flexneri(n = 1), S. boydii(n = 1) and S. sonnei(n = 4).
Y. enterocolitica(n = 3), Y. fredricksenii(n = 1), and Y. intermedia(n = 1).
That is, the P value determined using McNemar's test comparing the culture and PCR results.