Automated detection of WBC intracellular malaria-associated pigment (hemozoin) with Abbot Cell-Dyn 3200 and Cell-Dyn 3700 analyzers: Overview and results from the South African Institute of Medical Research (SAIMR) II evaluation

This report reviews current diagnostic approaches to malaria and focuses on the emerging role of malaria pigment (hemozoin) detection by automated depolarization analysis using Cell-Dyn 3200 and Cell-Dyn 3700 analyzers. In endemic malaria regions, the high frequency of severe clinical complications and mortality from malaria is exacerbated by poverty, limited access to appropriate clinical expertise, prohibitive costs of diagnostic investigations, and a widespread absence of testing facilities in rural areas. For nonendemic areas such as Europe and the United States where diagnostic and laboratory facilities within community health care systems are less limited by cost or availability, most deaths are due to a failure to actually consider or suspect malaria as a diagnosis. This failure to diagnose malaria is important because the importation of malaria into nonendemic areas is significant, and missed or delayed diagnosis of malaria is not uncommon. An initial collaborative evaluation of the diagnostic utility of Cell-Dyn 3500 instrument depolarization patterns in malaria was undertaken in 1996 at the South African Institute of Medical Research (SAIMR) in Johannesburg to establish the relationship between different depolarization patterns and the clinical presence/absence of malaria, and a second prospective study was completed in 2000. This latter study of 850 samples was designed to evaluate and compare in parallel the MAPSS (multiangle-polarized scatter separation) depolarization patterns of the Cell-Dyn 3200 and Cell-Dyn 3700. The results are documented for the first time in this communication and these indicate that by providing an early and highly specific alert, Cell-Dyn Dyn analysis has the real potential to prevent the development of serious clinical complications in situations in which there is little or no clinical suspicion that a patient has malaria.