title: Changes in the total leukocyte and platelet counts in Papuan and non Papuan adults from northeast Papua infected with acute Plasmodium vivax or uncomplicated Plasmodium falciparum malaria.
abstract: BACKGROUND
  There are limited data on the evolution of the leukocyte and platelet counts in malaria patients.
  
  
  METHODS
  In a clinical trial of chloroquine vs. chloroquine plus doxycycline vs. doxycycline alone against Plasmodium vivax (n = 64) or Plasmodium falciparum (n = 98) malaria, the total white cell (WCC) and platelet (PLT) counts were measured on Days 0, 3, 7 and 28 in 57 indigenous Papuans with life long malaria exposure and 105 non Papuan immigrants from other parts of Indonesia with limited malaria exposure.
  
  
  RESULTS
  The mean Day 0 WCC (n = 152) was 6.492 (range 2.1-13.4) x 10(9)/L and was significantly lower in the Papuans compared to the non Papuans: 5.77 x 10(9)/L vs. 6.86 x 10(9)/L, difference = -1.09 [(95% CI -0.42 to -1.79 x 10(9)/L), P = 0.0018]. 14 (9.2%) and 9 (5.9%) patients had leukopaenia (<4.0 x 10(9)/L) and leukocytosis (>10.0 x 10(9)/L), respectively. By Day 28, the mean WCC increased significantly (P = 0.0003) from 6.37 to 7.47 x 10(9)/L (73 paired values) and was similar between the two groups. Ethnicity was the only WCC explanatory factor and only on Day 0.The mean Day 0 platelet count (n = 151) was 113.0 (range 8.0-313.0) x 10(9)/L and rose significantly to 186.308 x 10(9)/L by Day 28 (P < 0.0001). There was a corresponding fall in patient proportions with thrombocytopaenia (<150 x 10(9)/L): 119/151 (78.81%) vs. 16/73 (21.92%, P < 0.00001). Papuan and non Papuan mean platelet counts were similar at all time points. Only malaria species on Day 0 was a significant platelet count explanatory factor. The mean D0 platelet counts were significantly lower (P = 0.025) in vivax (102.022 x 10(9)/L) vs. falciparum (122.125 x 10(9)/L) patients.
  
  
  CONCLUSIONS
  Changes in leukocytes and platelets were consistent with other malaria studies. The Papuan non Papuan difference in the mean Day 0 WCC was small but might be related to the difference in malaria exposure.
authors.affiliation: The US Navy Medical Research Unit no. 2, Jakarta, Indonesia. btaylor@oucru.org
authors.forename: Walter R J
authors.initials: WR
authors.lastname: Taylor
authors.forename: Hendra
authors.initials: H
authors.lastname: Widjaja
authors.forename: Hasan
authors.initials: H
authors.lastname: Basri
authors.forename: Colin
authors.initials: C
authors.lastname: Ohrt
authors.forename: Taufik
authors.initials: T
authors.lastname: Taufik
authors.forename: Emiliana
authors.initials: E
authors.lastname: Tjitra
authors.forename: Samuel
authors.initials: S
authors.lastname: Baso
authors.forename: David
authors.initials: D
authors.lastname: Fryauff
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Hoffman
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Richie
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D054242:Emigrants and Immigrants; D005260:Female; D006801:Humans; D007214:Indonesia; D007958:Leukocyte Count; D007964:Leukocytosis; D007970:Leukopenia; D016778:Malaria, Falciparum / Q000150:complications* / Q000473:pathology; D016780:Malaria, Vivax / Q000150:complications* / Q000473:pathology; D008297:Male; D010976:Platelet Count; D044382:Population Groups; D013921:Thrombocytopenia; D055815:Young Adult