TABLE 2.
Comparison of BioCode GPP and reference methods in the positive identification of 17 GI pathogensa,b
| BioCode GPP results | Reference method results | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Target organism | Unpreserved frozen | Unpreserved fresh | Cary-Blair fresh | Prospective total | Reference method | Unpreserved frozen | Unpreserved fresh | Cary-Blair fresh | Prospective total | Total specimens |
| Campylobacter spp. | 19 | 3 | 13 | 35 | a | 3 | 1 | 3 | 7 | 1,553 |
| C. difficile | 0 | 28 | 41 | 69 | b | 0 | 27 | 38 | 65 | 597 |
| Escherichia coli O157 | 5 | 0 | 2 | 7 | c | 2 | 0 | 0 | 2 | 1,554 |
| STEC | 4 | 2 | 2 | 8 | d | 3 | 0 | 0 | 3 | 1,520 |
| EAEC | 28 | 1 | 22 | 51 | e | 29 | 1 | 18 | 48 | 1,542 |
| ETEC | 12 | 6 | 15 | 33 | e | 10 | 3 | 14 | 27 | 1,543 |
| Salmonella spp. | 26 | 5 | 6 | 37 | c | 22 | 3 | 5 | 30 | 1,554 |
| Shigella/EIEC | 15 | 4 | 4 | 23 | c | 5 | 1 | 2 | 8 | 1,554 |
| Vibrio parahaemolyticus | 2 | 1 | 0 | 3 | a | 0 | 0 | 0 | 0 | 1,555 |
| Vibrio spp. (not V. parahaemolyticus) | 0 | 0 | 0 | 0 | a | 0 | 0 | 0 | 0 | 1,554 |
| Yersinia enterocolitica | 5 | 1 | 4 | 10 | a | 0 | 0 | 0 | 0 | 1,554 |
| Cryptosporidium spp. | 7 | 1 | 5 | 13 | e | 7 | 1 | 3 | 11 | 1,542 |
| Entamoeba histolytica | 0 | 0 | 0 | 0 | e | 0 | 0 | 0 | 0 | 1,542 |
| Giardia lamblia | 8 | 1 | 2 | 11 | e | 2 | 0 | 1 | 3 | 1,542 |
| Adenovirus 40/41 | 10 | 2 | 0 | 12 | e | 10 | 0 | 0 | 10 | 1,542 |
| Norovirus GI/GII | 43 | 1 | 6 | 50 | f | 39 | 1 | 7 | 47 | 1,553 |
| Rotavirus A | 27 | 2 | 1 | 30 | f | 20 | 1 | 1 | 22 | 1,553 |
| Total positives | 211 | 58 | 123 | 392 | 152 | 39 | 92 | 283 | ||
a, culture; b, FDA-cleared NAAT (Xpert C. difficile); c, enrichment culture; d, enrichment culture + FDA antigen test (EIA); e, composite result of PCR/sequencing (Applied BioCode); f, composite result of PCR/sequencing (CDC). STEC, Shiga toxin-producing E. coli; EAEC, enteroaggregative E. coli; ETEC, enterotoxigenic E. coli; EIEC, enteroinvasive E. coli. NAAT, Nucleic Acid Amplification Test, CDC, Centers for Disease Control and Prevention.
Unpreserved stool specimens were tested fresh for C. difficile, culture, and EIA and were either collected and tested fresh or frozen at ≤−65°C prior to testing with BioCode GPP or PCR/sequencing. Reference method for each pathogen is described in the footnotes. Results for C. difficile were tabulated only from fresh specimens.