Persistence of P. falciparum diagnostic antigens after treatment with artemisinins: association with parasite stage and mechanism of clearance
Issued Date
2014
Resource Type
Language
eng
Rights
Mahidol University
Suggested Citation
Elizabeth A Ashley, Kasia Stepniewska, Carole Fogg, Marion Barends, Roger Twesigye, Lily Keereecharoen, James Kiguli, Carit ler Moo, Carolyn Nabasumba, Anchalee Jaidee, Vincent Batwala, Khin Maung Lwin, Patrice Piola, Rose McGready, Philippe J Guerin, Kesinee Chotivanich, เกศินี โชติวานิช, Hugh Kingston, Arjen Dondorp, Nicholas J White, François Nosten, Charles J Woodrow (2014). Persistence of P. falciparum diagnostic antigens after treatment with artemisinins: association with parasite stage and mechanism of clearance. Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/63145
Title
Persistence of P. falciparum diagnostic antigens after treatment with artemisinins: association with parasite stage and mechanism of clearance
Author(s)
Elizabeth A Ashley
Kasia Stepniewska
Carole Fogg
Marion Barends
Roger Twesigye
Lily Keereecharoen
James Kiguli
Carit ler Moo
Carolyn Nabasumba
Anchalee Jaidee
Vincent Batwala
Khin Maung Lwin
Patrice Piola
Rose McGready
Philippe J Guerin
Kesinee Chotivanich
เกศินี โชติวานิช
Hugh Kingston
Arjen Dondorp
Nicholas J White
François Nosten
Charles J Woodrow
Kasia Stepniewska
Carole Fogg
Marion Barends
Roger Twesigye
Lily Keereecharoen
James Kiguli
Carit ler Moo
Carolyn Nabasumba
Anchalee Jaidee
Vincent Batwala
Khin Maung Lwin
Patrice Piola
Rose McGready
Philippe J Guerin
Kesinee Chotivanich
เกศินี โชติวานิช
Hugh Kingston
Arjen Dondorp
Nicholas J White
François Nosten
Charles J Woodrow
Abstract
The most sensitive rapid diagnostic tests of P. falciparum are based on
detection of histidine-rich protein 2 (HRP2), but HRP2 persists in the
blood after treatment and cannot be used to assess treatment response.
We measured antigen levels over a 4-week period in ACT-treated hyperparasitaemic
patients with P. falciparum in Uganda and Thailand (prior to the emergence of
artemisinin resistance). Antigen clearance was quantified by calculation of area-undercurve
(AUC) after normalization to baseline antigen level. Whole blood HRP2 levels
showed a wide range of AUCs: Uganda median 415 d·% (range 48–2588); Thailand
590 d·% (33–1534). The primary determinant of AUC was admission stage; in patients
presenting with >75% tiny/small rings (32/40 in Uganda, 24/38 in Thailand), median
HRP2 AUCs were respectively 6.4 and 10.7-fold higher than cases with later stages
(p=0.0005, <0.0001). Stage was also a key determinant of the time for the Paracheckä
RDT to become negative during follow-up. These data support the hypothesis that
the mechanism for HRP2 persistence is pitting in the spleen since once-infected
erythrocytes returning to the circulation can provide a source for persistently high
levels of HRP2 and ongoing positivity of HRP2-based RDTs.
Description
Joint International Tropical Medicine Meeting 2014: 3D perspectives on tropical medicine: drivers, diversity and determination the 8th seminar on food-and water-borne parasitic zoonoses: 2-4 December 2014: Centara Grand Bangkok Convention Center at Central World, Bangkok, Thailand. Bangkok: Faculty of Tropical Medicine, Mahidol University; 2014. p. 227.