title: A morphology-based method for the diagnosis of red blood cells parasitized by Plasmodium malariae and Plasmodium ovale.
abstract: BACKGROUND
  The morphology of red blood cells (RBCs) is altered significantly during the maturation stages of malaria parasites, which include ring, trophozoite, and schizont. There is dissimilarity in terms of the morphological characteristics of parasitized RBCs infected by the 4 species of Plasmodium, including falciparum, vivax, malariae, and ovale. This makes the process of diagnosis very difficult, which may lead to a wrong treatment method and substantial damage to the health of the patient. An innovative technique in introduced that accurately defines the shape of parasitized RBCs at each stage of infection as a potential method of diagnosis.
  
  
  METHODS
  Giemsa-stained thin blood films were prepared using blood samples collected from healthy donors as well as patients infected with P. malariae and P. ovale. The diameter and thickness of healthy and infected RBCs at each stage of infection were measured from their optical images using Olysia and Scanning Probe Image Processor (SPIP) software, respectively. A shape equation was fitted based on the morphological characteristics of RBCs, and their relative 2-dimensional shapes were plotted using Wolfram Mathematica.
  
  
  RESULTS
  At the ring stage, the thicknesses of RBCs parasitized by P. malariae (Pm-RBCs) and P. ovale (Po-RBCs) increased by 42% and 51%, respectively. Both Pm-RBCs and Po-RBCs remained nearly biconcave throughout parasite development even though their volumes increased.
  
  
  CONCLUSIONS
  It is proposed that the morphology-based characterization technique introduced here could be used to intensify the accuracy of the Giemsa staining diagnosis method for the detection of the Plasmodium genus and infection stage. Based on the significant morphological alterations induced by different Plasmodium species, the results may also find practical use for faster prediction and treatment of human malaria.
authors.affiliation: From the School of Mechanical Engineering, Iran University of Science and Technology , Tehran , Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Karimi
authors.forename: Mahdi
authors.initials: M
authors.lastname: Navidbakhsh
authors.forename: Afsaneh Motevalli
authors.initials: AM
authors.lastname: Haghi
authors.forename: Shahab
authors.initials: S
authors.lastname: Faghihi
mesh_terms: D001399:Azure Stains; D048430:Cell Shape; D004912:Erythrocytes / Q000469:parasitology* / Q000473:pathology; D006801:Humans; D008288:Malaria / Q000097:blood* / Q000469:parasitology* / Q000473:pathology; D008853:Microscopy / Q000379:methods; D061848:Optical Imaging / Q000379:methods; D010965:Plasmodium malariae / Q000302:isolation & purification*; D041122:Plasmodium ovale / Q000302:isolation & purification*
chemical_list: D001399:Azure Stains