title: Antigen persistence of rapid diagnostic tests in pregnant women in Nanoro, Burkina Faso, and the implications for the diagnosis of malaria in pregnancy.
abstract: OBJECTIVE
  To evaluate persistence of several Plasmodium antigens in pregnant women after treatment and compare diagnostics during treatment follow-up.
  
  
  METHODS
  Thirty-two pregnant women (N = 32) with confirmed malaria infection by a histidine-rich protein 2 (HRP2)-based rapid diagnostic test (RDT) and microscopy were followed for 28 days after artemisinin-based combination therapy (ACT). A Plasmodium lactate dehydrogenase (pLDH)-based RDT and two ELISAs based on the detection of dihydrofolate reductase-thymidylate synthase (DHFR-TS) and haeme detoxification protein (HDP) were compared with each other and to RT-PCR at each visit.
  
  
  RESULTS
  The mean visit number (95% confidence interval) on which the HRP2-based RDT was still positive after treatment was 3.4 (2.7-4.1) visits with some patients still positive at day 28. This is significantly later than the pLDH-based RDT [0.84 (0.55-1.1)], microscopy (median 1, range 1-3), DHFR-TS-ELISA [1.7 (1.1-2.3)] and RT-PCR (median 2, range 1-5) (P < 0.05), but not significantly later than HDP-ELISA [2.1 (1.6-2.7)]. Lower gravidity and higher parasite density at day 0 resulted in significantly longer positive results with most tests (P < 0.05).
  
  
  CONCLUSIONS
  HRP2 can persist up to 28 days after ACT treatment; therefore, this test is not suitable for treatment follow-up in pregnant women and can generate problems when using this test during intermittent preventive treatment (IPTp). DHFR-TS is less persistent than HRP2, making it a potentially interesting target for diagnosis.
authors.affiliation: Koninklijk Instituut Voor de Tropen, Amsterdam, The Netherlands. e.kattenberg@kit.nl
authors.forename: Johanna H
authors.initials: JH
authors.lastname: Kattenberg
authors.forename: Christian M
authors.initials: CM
authors.lastname: Tahita
authors.forename: Inge A J
authors.initials: IA
authors.lastname: Versteeg
authors.forename: Halidou
authors.initials: H
authors.lastname: Tinto
authors.forename: Maminata
authors.initials: M
authors.lastname: Traoré-Coulibaly
authors.forename: Henk D F H
authors.initials: HD
authors.lastname: Schallig
authors.forename: Petra F
authors.initials: PF
authors.lastname: Mens
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D000890:Anti-Infective Agents / Q000627:therapeutic use; D000953:Antigens, Protozoan / Q000097:blood*; D037621:Artemisinins / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood; D002050:Burkina Faso; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D016778:Malaria, Falciparum / Q000175:diagnosis* / Q000188:drug therapy / Q000276:immunology*; D009097:Multienzyme Complexes / Q000097:blood; D010963:Plasmodium falciparum / Q000469:parasitology; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic / Q000175:diagnosis* / Q000188:drug therapy / Q000276:immunology*; D015800:Protozoan Proteins / Q000097:blood; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D013762:Tetrahydrofolate Dehydrogenase / Q000097:blood; D013940:Thymidylate Synthase / Q000097:blood; D016896:Treatment Outcome
chemical_list: D000890:Anti-Infective Agents; D000953:Antigens, Protozoan; D037621:Artemisinins; D015415:Biomarkers; C529576:HDP protein, Plasmodium falciparum; D009097:Multienzyme Complexes; D015800:Protozoan Proteins; C056930:thymidylate synthase-dihydrofolate reductase; C031327:artemisinin; D007770:L-Lactate Dehydrogenase; D013762:Tetrahydrofolate Dehydrogenase; D013940:Thymidylate Synthase