Hygiene INTRODUCTIONEarly detection of malaria in patients not suspected of having the disease is a potential novel application for modern hematology analyzers like the Sysmex XE-2100 (Sysmex Corporation, Kobe, Kansai, Japan). A prompt and accurate diagnosis is critical to reduce adverse outcomes associated with malaria, including death. 1 In endemic regions, malaria is a prime diagnostic concern in febrile patients, and expert thickfilm evaluation is usually available.2 However, the accuracy of microscopic malaria diagnosis in less experienced centers or in non-endemic regions may be lower, and health personnel is less likely to consider the disease, leading to delayed diagnoses.1 Automated full blood counts (FBC) are usually performed in patients with febrile illnesses, providing a unique opportunity to guide a timely parasitological malaria diagnosis.Hematology analyzers evaluated for malaria detection include the Cell-Dyn (Abbott Diagnostics, Santa Clara, CA), 3 the GEN.S and LH-750 (Beckman Coulter, Miami, FL), 4 and the XE-2100 and XS-1000 i (Sysmex Corporation, Kobe, Kansai, Japan). 5,6 The Sysmex XE-2100 is an automated hematology analyzer that uses flow cytometry, direct current (DC) impedanciometry, and radiofrequency conductance (RF) to detect and measure blood corpuscular elements.7 Flow cytometry may detect malaria parasites or parasite debris such as free hemozoin or hemozoin-laden macrophages as reported for Cell-Dyn instruments.8 For the Sysmex XE-2100, two case series reported a gap between the manual and automated eosinophil counts (pseudoeosinophilia) and abnormal granulocyte-coded events in the DIFF scatterplot used for white blood cell (WBC) separation based on fluorescence versus side-scatter signals in samples from Plasmodium vivaxinfected patients.9, 10 Later, Huh and others 5 found that the two previously reported abnormalities, compared with thick film, had a sensitivity of 69.4% and a specificity of 100% for P. vivax diagnosis. These findings suggest the potential clinical utility of malaria detection by the XE-2100. Ideally, to improve the clinical impact of this detection method, it should be an automated process relying on the analyzer's quantitative data and expressed as a "malaria alarm" that could motivate the microscopic search for malaria.The primary aim of this study was to develop, validate, and test the accuracy of one observer-dependent (OD) and two non-observer-dependent (N-OD) diagnostic prediction models for P. vivax and P. falciparum malaria. The approach for developing the OD models was similar to previous studies using the XE-2100 for malaria diagnosis 5 with the inclusion of other clinical and scatterplot variables not previously investigated. The N-OD models were developed to obtain a framework for an automated malaria-detection algorithm for the XE-2100. Secondary aims were to determine the occurrence of pseudoeosinophilia and to explore a possible cause for the XE-2100 FBC malaria-related abnormalities. MATERIALS AND METHODSStudy population. Blood samples were col...

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RESUMOIntrodução: É frequente a associação da malária com complicações como prematuridade, retardo no crescimento intrauterino, baixo peso ao nascer e mortalidade infantil, efeitos pouco estudados em áreas hipoendêmicas para malaria. O objetivo deste estudo foi analisar a relação da malária gestacional com estes efeitos em recém-nascidos numa região endêmica para malária na Colômbia, entre 1993 e 2007. Métodos: Foram estudadas as características em 1.716 recém-nascidos num estudo de coorte. Fez-se seguimento em 394 gestantes com malária (27% por Plasmodium falciparum e 73% por P. vivax) e 1.322 sem malária. Resultados: Foi encontrada uma relação entre a exposição à malária na gestação e o risco maior de baixo peso ao nascer (RR = 1,37; 1,03-1,83), assim como estatura baixa (RR = 1,52; 1,25-1,85), retardo no crescimento intrauterino (RR = 1,29; 1,0-1,66) e prematuridade (RR = 1,68; 1,3-2,17). A frequência de nascimentos prematuros foi maior nas mães com malária por P. falciparum (77%) que aquelas com P. vivax (RR = 1,77; IC 95%: 1,2-2,6). Conclusões: O baixo peso ao nascer e o retardo no crescimento foi associado com malária na gestação na Colômbia. A infecção por P. vivax foi relacionada com efeitos adversos sobre o recém-nascido, de modo semelhante em relação ao P. falciparum. Palavras-chaves: Malária na gestação. Recém-nascidos. Peso ao nascer. Retardo no crescimento intrauterino. Prematuridade. ABSTRACT Introduction:Association between malaria and pregnancy complications, such as prematurity, intrauterine growth restriction, low birthweight and infant mortality has been reported. These effects have been studied widely in areas hyperendemic for malaria, but studies in low-endemic areas are scarce. The study investigated the relation between gestational malaria and low birthweight and intrauterine growth retardation in neonates of a malarial endemic region in Colombia, between 1993 and 2007. Methods: The pattern of development in 1,716 neonates of women with and without malaria infection during pregnancy was evaluated in a cohort study. A total of 394 infected (27% by P. falciparum and 73% by P. vivax) and 1,322 noninfected pregnant women were followed. Results: Exposure to gestational malaria was associated with increased risk of low birth weight (RR = 1.37; 1.03-1.83), short height (RR = 1.52; 1.25-1.85), intrauterine growth retardation (RR = 1.29; 1.0-1.66) and prematurity (RR = 1.68; 1.3-2.17). Prematurity was 77% higher in infants of mothers with malaria by P. falciparum than infants of mothers with malaria by P. vivax (RR = 1.77; 1.2-2.6). Conclusions: Low birth weight and intrauterine growth retardation were associated with malaria during pregnancy. Infection with P. vivax was related with adverse effects on the newborn, similar to that reported for P. falciparum.

Plasmodium falciparum sensitivity to chloroquine (CHL), amodiaquine (AMO)