title: Prognostic significance of reduced red blood cell deformability in severe falciparum malaria.
abstract: Severe falciparum malaria is associated with microvascular obstruction resulting from sequestration of erythrocytes containing mature stages of the parasite. Since reduced red blood cell deformability (RBC-D) can contribute to impaired microcirculatory flow, RBC-D was measured in 23 patients with severe falciparum malaria (seven of whom subsequently died), 30 patients with uncomplicated malaria, and 17 healthy controls. The RBC-D, measured by ektacytometry, was significantly reduced in severe malaria and was particularly low in all fatal cases. At a low shear stress of 1.7 Pascal (Pa), a red blood cell elongation index less than 0.21 on admission to the hospital predicted fatal outcome with a sensitivity of 100% (confidence interval [CI] = 59-100%) and a specificity of 88% (CI = 61-98%). The reduction in the RBC-D appeared to result mainly from changes in unparasitized erythrocytes. Reduced deformability of unparasitized red blood cells in severe malaria may contribute to impaired microcirculatory flow and a fatal outcome in severe falciparum malaria.
authors.affiliation: Department of Internal Medicine,Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: A M
authors.initials: AM
authors.lastname: Dondorp
authors.forename: B J
authors.initials: BJ
authors.lastname: Angus
authors.forename: M R
authors.initials: MR
authors.lastname: Hardeman
authors.forename: K T
authors.initials: KT
authors.lastname: Chotivanich
authors.forename: K
authors.initials: K
authors.lastname: Silamut
authors.forename: R
authors.initials: R
authors.lastname: Ruangveerayuth
authors.forename: P A
authors.initials: PA
authors.lastname: Kager
authors.forename: N J
authors.initials: NJ
authors.lastname: White
authors.forename: J
authors.initials: J
authors.lastname: Vreeken
mesh_terms: D000328:Adult; D004907:Erythrocyte Deformability; D006801:Humans; D016778:Malaria, Falciparum / Q000097:blood*; D008833:Microcirculation; D011379:Prognosis