|
|
||||||||
Severe and fatal malaria is associated with the increased presence of malaria hemozoin in peripheral phagocytes. Large studies of this relationship are hampered by the fact that identifying and counting phagocytes on thick blood smears is time consuming. Distinguishing which mononuclear cells are monocytes and which granulocytes are neutrophils requires time and careful training. In this study, we evaluated a simplified method in which only the proportions of hemozoin-containing mononuclear cells and granulocytes are counted. Thick blood films from 471 Gabonese children with malaria were evaluated. We found a linear relationship and a strong correlation between the proportions of hemozoin-containing monocytes versus mononuclear cells (r = 0.85) and neutrophils versus polymorphonuclear cells (r = 0.93), respectively. The two methods had similar predictive values, as estimated by receiver operating characteristics curves. This simplified method can be used to estimate the amount of extra-erythrocytic pigment in peripheral blood, and we suggest that it may be particularly suitable for very large studies.
Received December 27, 2004. Accepted for publication March 11, 2005.
Acknowledgments: We thank David Wypij for biostatistical oversight of the Severe Malaria in African Children clinical studies and for manuscript review, Professor Klaus Dietz for help with the statistical analysis, and Marcel Nkeyi for technical laboratory help.
Financial support: This study was supported by a grant from the U.S. National Institutes of Health, National Institute of Allergy and Infectious Diseases (AI 45955).
* Address correspondence to Bertrand Lell, Medical Research Unit, Albert Schweitzer Hospital, BP 118, Lambaréné, Gabon and Department of Parasitology, Institute of Tropical Medicine, University of Tübingen, Wilhelmstrasse 27, D-72074 Tübingen, Germany. E-mail: bertrand.lell{at}uni-tuebingen.de
Authors addresses: Bertrand Lell, Michel A. Missinou, Saadou Issifou, Pierre-Blaise Matsiegui, and Peter G. Kremsner, Medical Research Unit, Albert Schweitzer Hospital, BP 118, Lambaréné, Gabon, Telephone: 241-581-099, Fax: 241-581-196 and Department of Parasitology, Institute of Tropical Medicine, University of Tübingen, Wilhelmstrasse 27, D-72074 Tübingen, Germany, Telephone: 49-7071-298-0240, Fax: 49-7071-295-189, E-mail: bertrand.lell{at}uni-tuebingen.de. Christopher H. O. Olola, Centre for Geographical Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Programme, PO Box 230, Kilifi, Kenya. Terrie E. Taylor, Department of Internal Medicine, College of Osteopathic Medicine, Michigan State University, B309-B W. Fee Hall, East Lansing, MI 48824, Fax 517-432-1062.
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |