Evaluation of real-time PCR assay to detect Schistosoma mansoni infections in a low endemic setting

Autor(es):Mostrar menos -

Carvalho Espirito-Santo, Maria Cristina ^{[1, 2]} ; Alvarado-Mora, Monica Viviana ^[3] ; Dias-Neto, Emmanuel ^{[4, 5, 6]} ; Botelho-Lima, Livia Souza ^[3] ; Moreira, Joao Paulo ^[3] ; Amorim, Maria ^[5] ; Silva Pinto, Pedro Luiz ^[7] ; Heath, Ashley R. ^[8] ; Pagliusi Castilho, Vera Lucia ^[9] ; do Nascimento Goncalves, Elenice Messias ^[9] ; de Albuquerque Luna, Expedito Jose ^[10] ; Carrilho, Flair Jose ^[3] ; Rebello Pinho, Joao Renato ^[3] ; Borges Gryschek, Ronaldo Cesar ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Med, Dept Infect & Parasit Dis, Sao Paulo - Brazil

^[2] Univ Ctr Volta Redonda, Volta Redonda, RJ - Brazil

^[3] Univ Sao Paulo, Sch Med, Dept Gastroenterol, Lab Trop Gastroenterol & Hepatol, Sao Paulo - Brazil

^[4] Univ Sao Paulo, Dept Psychiat, Sao Paulo - Brazil

^[5] AC Camargo Canc Ctr, Lab Med Genom, Sao Paulo - Brazil

^[6] Univ Sao Paulo, Alzira Denise Hertzog Silva LIM Inst27, Neurosci Lab, Sao Paulo - Brazil

^[7] Adolfo Lutz Inst, Parasitol & Mycol Serv, Dept Enteroparasites, Sao Paulo - Brazil

^[8] Sigma Custom Prod, The Woodlands, TX 77380 - USA

^[9] Univ Sao Paulo, Sch Med, Hosp Clin, Cent Lab Div, Parasitol Sect, Sao Paulo - Brazil

^[10] Univ Sao Paulo, Inst Trop Med, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: BMC INFECTIOUS DISEASES; v. 14, OCT 23 2014.
• Citações Web of Science: 14

Resumo

Background: Schistosomiasis constitutes a major public health problem, and 200 million people are estimated to be infected with schistosomiasis worldwide. In Brazil, schistosomiasis has been reported in 19 states, showing areas of high and medium endemicity and a wide range of areas of low endemicity (ALE). Barra Mansa in Rio de Janeiro state has an estimated prevalence of 1%. ALE represent a new challenge for the helminth control because about 75% of infected individuals are asymptomatic and infections occur with a low parasite load (<100 eggs per gram of feces), causing a decrease in sensitivity of stool parasitological techniques, which are a reference for the laboratory diagnosis of this helminth. The objective of this study was to evaluate the performance of a TaqMan quantitative polymerase chain reaction (qPCR) technique in serum and feces DNA samples using the techniques of Kato-Katz (KK), Hoffman, Pons and Janer (HH) as references, during an epidemiological survey using fecal samples and sera from randomized residents from an ALE. Methods: A cross-sectional study conducted from April to December 2011 using a probabilistic sampling that collected 572 fecal and serum samples. The laboratory diagnostic techniques used were: KK, HH and qPCR ( feces and serum). Results: We obtained the following results using the different diagnostic techniques: KK and HH, 0.9% (n = 5); qPCR-feces, 9.6% (n = 55); and qPCR-serum, 1.4% (n = 8). The qPCR-feces presented the highest positivity, whereas the techniques of HH and KK were the least sensitive to detect infections (0.8%). Compared to HH and KK, qPCR-feces showed a statistically significant difference in positivity (p < 0.05), although with poor agreement. Conclusion: The positivity rate presented by the qPCR approach was far higher than that obtained by parasitological techniques. The lack of adequate surveillance in ALE of schistosomiasis indicates a high possibility of these areas being actually of medium and high endemicity. This study presents a control perspective, pointing to the possibility of using combined laboratory tools in the diagnosis of schistosomiasis in ALE. (AU)

• Processo FAPESP: 08/50461-6 - Estudo da variabilidade genotípica dos vírus da Hepatite B e Hepatite C na Colômbia
• Beneficiário: Monica Viviana Alvarado Mora
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 10/52615-0 - Estudo comparativo de metodos diagnosticos da esquistossomose mansoni em areas de baixa transmissao e prevalencia.
• Beneficiário: Ronaldo Cesar Borges Cryschek
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 07/53457-7 - Estudo da variabilidade genotípica dos vírus das Hepatites B e C na Colômbia
• Beneficiário: João Renato Rebello Pinho
• Modalidade de apoio: Auxílio à Pesquisa - Regular