TABLE 2.
Prevalence of Pfmrp1 genotypes for amino acid positions 876 and 1466 and Pfdhfr Pfdhps haplotypes in P. falciparum infections at baseline (D0) and at times of recurrent parasitemia after SP treatment
| Gene(s) and amino acid encoded or haplotype description | No. of positive samples/total no. of samples successfully tested (ratio)a at:
|
||
|---|---|---|---|
| D0d | Time of recrudescence | Time of reinfection | |
| Pfmrp1 | |||
| 1466K | 52/101 (0.515) | 12/14 (0.857)* | 14/21 (0.667) |
| 1466R | 25/101 (0.248) | 0/14 (0.000)* | 2/21 (0.095) |
| 1466K/R | 24/101 (0.238) | 2/14 (0.143) | 5/21 (0.238) |
| 876I | 75/104 (0.721) | 12/13 (0.923) | 18/23 (0.783) |
| 876V | 13/104 (0.125) | 1/13 (0.077) | 2/23 (0.087) |
| 876I/V | 16/104 (0.154) | 0/13 (0.000) | 3/23 (0.130) |
| Pfdhfr and Pfdhpsb | |||
| Wild type | 3/96 (0.031) | 0/15 (0.000) | 0/22 (0.000) |
| Single mutant | 1/96 (0.010) | 0/15 (0.000) | 0/22 (0.000) |
| Double mutant | 21/96 (0.219) | 0/15 (0.000) | 1/22 (0.046) |
| Triple mutant | 36/96 (0.375) | 1/15 (0.067) | 0/22 (0.048) |
| Quadruple mutant | 15/96 (0.157) | 0/15 (0.000) | 4/22 (0.182) |
| Quintuple mutantc | 20 (3 + 17)/96 (0.208) | 14 (0 + 14)/15 (0.933)** | 17 (3 + 14)/22 (0.773)* |
*, P < 0.05;**, P ≤ 0.001. Fisher's exact two-tailed test was used to evaluate if there was a difference in SNP prevalence between the baseline and the recrudescence and reinfection samples.
Pfdhfr Pfdhps haplotypes were defined according to the nomenclature proposed by Kublin and colleagues (12).
The numbers of samples with mixed and pure quintuple mutants (mixed + pure), respectively, are shown.
The frequencies prior to the administration of the drug at D0 are based on samples from all of the patients enrolled in the study, independent of which treatment arm they were allocated to.