Table 2. Discordance between microscopy and PCR in microscopy-positives.
| Parasite species | Number of microscopy-positive cases being PCR-negative (number of parasites observed per technique) | Total number of microscopy-positives | |||||
|---|---|---|---|---|---|---|---|
| Direct smear | FEC | Kato smear | Baermann | Coproculture | Total | ||
| S. stercoralis | 1 (1) | 0 | NA | 7 a | 5 (6–141) a | 12 | 100 |
| Hookworm | 0 | 1 (2) b | 3 (1–47) b | NA | 7 (2–1000) b | 9 | 98 |
| A. lumbricoides | 2 (1) | 5 (1–4) | 0 | NA | NA | 7 | 161 |
| S. mansoni | 0 | 0 | 1 (1) c | NA | NA | 1 | 5 |
| G. intestinalis d | 0 | 1 (1–10) | NA | NA | NA | 1 | 24 |
FEC, Formal-ether concentration; NA, Not applicable
a One case was detected by coproculture as well as the Baermann method. In addition to stool, Baermann medium and coproculture medium were analyzed by PCR in the 7 Baermann-positives and 3/5 coproculture-positives, respectively. These samples also tested negative.
b One case was detected by FEC, Kato smear as well as coproculture.
c In addition, 3 S. haematobium eggs were observed
d Parasite numbers were determined semi-quantitatively.