title: Improved light microscopy counting method for accurately counting Plasmodium parasitemia and reticulocytemia.
abstract: Even with the advances in molecular or automated methods for detection of red blood cells of interest (such as reticulocytes or parasitized cells), light microscopy continues to be the gold standard especially in laboratories with limited resources. The conventional method for determination of parasitemia and reticulocytemia uses a Miller reticle, a grid with squares of different sizes. However, this method is prone to errors if not used correctly and counts become inaccurate and highly time-consuming at low frequencies of target cells. In this report, we outline the correct guidelines to follow when using a reticle for counting, and present a new counting protocol that is a modified version of the conventional method for increased accuracy in the counting of low parasitemias and reticulocytemias. Am. J. Hematol. 91:852-855, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts.
authors.forename: Caeul
authors.initials: C
authors.lastname: Lim
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington.|Department of Medicine, Goa Medical College and Hospital, Bambolim, Goa, India.
authors.forename: Ligia
authors.initials: L
authors.lastname: Pereira
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington.|Department of Medicine, Goa Medical College and Hospital, Bambolim, Goa, India.
authors.forename: Pritish
authors.initials: P
authors.lastname: Shardul
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington.|Department of Medicine, Goa Medical College and Hospital, Bambolim, Goa, India.
authors.forename: Anjali
authors.initials: A
authors.lastname: Mascarenhas
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Maki
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington.
authors.forename: Jordan
authors.initials: J
authors.lastname: Rixon
authors.affiliation: Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Shaw-Saliba
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington.
authors.forename: John
authors.initials: J
authors.lastname: White
authors.affiliation: Department of Pediatrics, Goa Medical College and Hospital, Bambolim, Goa, India.
authors.forename: Maria
authors.initials: M
authors.lastname: Silveira
authors.affiliation: Department of Medicine, Goa Medical College and Hospital, Bambolim, Goa, India.
authors.forename: Edwin
authors.initials: E
authors.lastname: Gomes
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington.
authors.forename: Laura
authors.initials: L
authors.lastname: Chery
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington.
authors.forename: Pradipsinh K
authors.initials: PK
authors.lastname: Rathod
authors.affiliation: Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts.
authors.forename: Manoj T
authors.initials: MT
authors.lastname: Duraisingh
mesh_terms: D004906:Erythrocyte Count / Q000379:methods; D006801:Humans; D008722:Methods; D008853:Microscopy / Q000379:methods; D018512:Parasitemia / Q000097:blood / Q000175:diagnosis*; D010961:Plasmodium / Q000166:cytology; D012156:Reticulocytes / Q000469:parasitology*; D012680:Sensitivity and Specificity