TABLE 1.
Results of PCR amplification of 18S rRNA, COWP, and TRAP-C1 genes of C. parvum from DNA extracted from the feces of 218 patients diagnosed as having cryptosporidiosis
| Gene amplified by PCR and PCR result | No. (%) of patients with the following relative no. of oocysts observed by immunofluorescencea:
|
Total no. of patients positive (sensitivity [%]) by PCRb | ||||
|---|---|---|---|---|---|---|
| None | ± | + | 2+ | 3+ | ||
| 18S rRNA | ||||||
| Positive | 0 | 22 (96) | 98 (95) | 80 (99) | 4 (100) | 204 (97) |
| Negative | 7 | 1 | 5 | 1 | 0 | |
| COWP | ||||||
| Positive | 0 | 17 (74) | 91 (88) | 79 (98) | 4 (100) | 191 (91) |
| Negative | 7 | 6 | 12 | 2 | 0 | |
| TRAP-C1 | ||||||
| Positive | 0 | 14 (61) | 64 (62) | 57 (70) | 4 (100) | 139 (66) |
| Negative | 7 | 9 | 39 | 24 | 0 | |
| Genotypec | ||||||
| 1 | 3 | 32 | 37 | 2 | ||
| 2 | 16 | 60 | 42 | 2 | ||
a
Percentages were calculated on the basis of the proportion of the samples positive by PCR in each category.
b
Calculated only for samples in which oocysts were observed by immunofluorescence. Sensitivity is equal to number of samples PCR positive/total number of samples.
c
Results for 194 samples: 191 samples analyzed for the COWP gene plus an additional 3 samples analyzed for the TRAP-C1 gene (Table 2).