Investigating portable fluorescent microscopy (CyScope®) as an alternative rapid diagnostic test for malaria in children and women of child-bearing age

<p>Abstract</p> <p>Background</p> <p>Prompt and correct diagnosis of malaria is crucial for accurate epidemiological assessment and better case management, and while the gold standard of light microscopy is often available, it requires both expertise and time. Portable fluorescent microscopy using the CyScope^®offers a potentially quicker, easier and more field-applicable alternative. This article reports on the strengths, limitations of this methodology and its diagnostic performance in cross-sectional surveys on young children and women of child-bearing age.</p> <p>Methods</p> <p>552 adults (99% women of child-bearing age) and 980 children (99% ≤ 5 years of age) from rural and peri-urban regions of Ugandan were examined for malaria using light microscopy (Giemsa-stain), a lateral-flow test (Paracheck-Pf^®) and the CyScope^®. Results from the surveys were used to calculate diagnostic performance (sensitivity and specificity) as well as to perform a receiver operating characteristics (ROC) analyses, using light microscopy as the gold-standard.</p> <p>Results</p> <p>Fluorescent microscopy (qualitative reads) showed reduced specificity (<40%), resulting in higher community prevalence levels than those reported by light microscopy, particularly in adults (+180% in adults and +20% in children). Diagnostic sensitivity was 92.1% in adults and 86.7% in children, with an area under the ROC curve of 0.63. Importantly, optimum performance was achieved for higher parasitaemia (>400 parasites/μL blood): sensitivity of 64.2% and specificity of 86.0%. Overall, the diagnostic performance of the CyScope was found inferior to that of Paracheck-Pf^®.</p> <p>Discussion</p> <p>Fluorescent microscopy using the CyScope^®is certainly a field-applicable and relatively affordable solution for malaria diagnoses especially in areas where electrical supplies may be lacking. While it is unlikely to miss higher parasitaemia, its application in cross-sectional community-based studies leads to many false positives (i.e. small fluorescent bodies of presently unknown origin mistaken as malaria parasites). Without recourse to other technologies, arbitration of these false positives is presently equivocal, which could ultimately lead to over-treatment; something that should be further explored in future investigations if the CyScope^®is to be more widely implemented.</p

Avaliação antropométrica de adolescentes Kamayurá, povo indígena do Alto Xingu, Brasil Central (2000-2001) Anthropometric assessment of Kamayurá adolescents in the Upper Xingu, Central Brazil (2000-2001)

Apesar da proximidade dos grupos indígenas do Alto Xingu com a sociedade, os estudos têm mostrado adequação do peso para estatura e déficit de estatura para idade das crianças desses povos. Em relação aos adolescentes, pouco se conhece sobre suas condições nutricionais. O presente estudo teve como objetivo avaliar o estado nutricional de adolescentes Kamayurá, valendo-se de variáveis antropométricas. As medidas de peso, estatura, pregas cutâneas e circunferências corporais foram coletadas de 65 adolescentes, sendo 31 indivíduos masculinos e 34 femininos. As médias de estatura em relação à idade foram menores do que aquelas encontradas na Pesquisa Nacional sobre Saúde e Nutrição e na população de referência do National Center for Health Statistics. Houve taxa elevada de sobrepeso no sexo masculino (38,7%) e no feminino (23,5%); a obesidade foi encontrada em uma adolescente (2,9%). Nenhum adolescente com sobrepeso apresentou ambas as pregas tricipital e subescapular acima do percentil 90. Não houve casos de déficit nutricional em adolescentes de ambos os sexos. Apesar da alta prevalência de sobrepeso, o estado nutricional dos adolescentes em estudo é adequado, dada a baixa adiposidade.<br>Despite the proximity between indigenous groups in the Upper Xingu Region and Brazilian national society, studies have shown adequate weight-for-height and low height-for-age in indigenous children. Little is known about the nutritional status of indigenous adolescents. The present study aimed to evaluate the nutritional status of Kamayurá adolescents. Anthropometric variables were collected from a sample of 65 adolescents (31 males and 34 females). Mean height was lower than both that of the Brazilian National Survey on Health and Nutrition and the reference population of the U.S. National Center for Health Statistics. There was a high rate of overweight in both males (38.7%) and females (23.5%), and one female adolescent was obese (2.9%). No overweight adolescent presented both the triceps and subscapular skinfolds above the 90th percentile. There were no cases of nutritional deficit among either male or female adolescents. Despite the high prevalence of overweight, the nutritional status of these adolescents is adequate, since the group presents low adiposity