title: PCR assay in malaria diagnosis using filter paper samples from Jazan region, Saudi Arabia.
abstract: PCR assay using designed primers was evaluated in detecting human malaria infection from whole blood and/or on Whatman filter-paper compared to conventional microscopy. Two DNA extraction methods were used for dried blood-spots; QIAamp mini kit and methanol-fixation/heat-extraction. A total of 118 cases were collected from 4 hospitals at Jazan district. Microscopic examination showed positivity in 66/118 samples (56%). Thin films showed parasitaemia from 1+ to 4+. In PCR assay, 79 samples (70%) were positive for the genus Plasmodium given 153 base pair PCR product. All microscopy positive samples were PCR positive but PCR detected 13 cases missed by microscopy. As for filter-paper spot samples, 68 samples (57.6%) were PCR positive when DNA was extracted by QIAamp mini kit whereas 49 (41.5%) by methanol-fixation/heat-extracion method. PCR sensitivity decreased by using DNA extracted from filter-paper compared to microscopy and whole blood PCR. But the DNA isolated from filter paper detected parasites in many microscopy negative samples.
authors.affiliation: Department of Medical Parasitology, Faculty of Medicine, Umm Al-Qura University, Makkah, Kingdom of Saudi Arabia. alharthi@uqu.edu.sa
authors.forename: Saeed A
authors.initials: SA
authors.lastname: Al-Harthi
authors.forename: Manal B
authors.initials: MB
authors.lastname: Jamjoom
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001800:Blood Specimen Collection / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D016054:DNA, Protozoan / Q000032:analysis* / Q000737:chemistry / Q000235:genetics; D005260:Female; D005374:Filtration; D006801:Humans; D007223:Infant; D008288:Malaria / Q000175:diagnosis* / Q000469:parasitology; D008297:Male; D008853:Microscopy; D008875:Middle Aged; D018512:Parasitemia / Q000175:diagnosis* / Q000469:parasitology; D010961:Plasmodium / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods*; D012529:Saudi Arabia; D012680:Sensitivity and Specificity; D013045:Species Specificity; D055815:Young Adult
chemical_list: D016054:DNA, Protozoan