title: Rapid detection of Mycobacterium tuberculosis complex by real-time PCR in sputum samples and its use in the routine diagnosis in a reference laboratory.
abstract: Tuberculosis (TB) is an infectious disease of global distribution, constituting a serious public health problem in Brazil. São Paulo State, located in the south-east of Brazil, notified 16,580 new TB cases in 2013. The Instituto Adolfo Lutz is a public health reference laboratory for TB diagnosis for all the State. Considering that rapid and accurate diagnosis is essential for TB control, the aim of this study was to evaluate the use of an in-house real-time (RT)-PCR assay targeting the mpt64 gene in the routine diagnosis of TB, and to compare this technique with smear microscopy and culture. From August 2012 to October 2013, 715 sputum samples from 657 patients were included in the study. Smear microscopy, culture, phenotypic and PRA-hsp65 identification of mycobacteria, and mpt64 RT-PCR were performed. With respect to confirmed TB cases (n = 62/657; 9.4%), smear microscopy had a sensitivity of 82.3%. Culture and RT-PCR showed the same sensitivity, i.e. 90.3%. Specificity was 99.7, 99.4 and 98.6% for smear microscopy, culture and RT-PCR, respectively. mpt64 RT-PCR showed high sensitivity and specificity for the detection of Mycobacterium tuberculosis complex in sputum samples. This technique can be deployed in laboratories that do not have a rapid test for TB available, enabling the performance of TB diagnosis in up to 5 h.
authors: Department of Tuberculosis and Mycobacteriosis, Center of Bacteriology, Instituto Adolfo Lutz, Av. Dr Arnaldo, 355, 01246-902 São Paulo, SP, Brazil.
authors: Juliana Maira
authors: JM
authors: Watanabe Pinhata
authors: Center of Regional Laboratory of Santo Andre, Rua Ramiro Colleone, 240, 09040-160 Santo André, SP, Brazil.
authors: Maria Cecilia
authors: MC
authors: Cergole-Novella
authors: Center of Regional Laboratory of Santo Andre, Rua Ramiro Colleone, 240, 09040-160 Santo André, SP, Brazil.
authors: Andreia
authors: A
authors: Moreira Dos Santos Carmo
authors: Center of Regional Laboratory of Santo Andre, Rua Ramiro Colleone, 240, 09040-160 Santo André, SP, Brazil.
authors: Regina
authors: R
authors: Ruivo Ferro E Silva
authors: Department of Tuberculosis and Mycobacteriosis, Center of Bacteriology, Instituto Adolfo Lutz, Av. Dr Arnaldo, 355, 01246-902 São Paulo, SP, Brazil.
authors: Lucilaine
authors: L
authors: Ferrazoli
authors: Laboratory of Molecular Diagnosis of Bacterial Infections, Center of Immunology, Instituto Adolfo Lutz, Av. Dr Arnaldo, 355, 01246-902 São Paulo, SP, Brazil.
authors: Claudio
authors: C
authors: Tavares Sacchi
authors: Department of Tuberculosis and Mycobacteriosis, Center of Bacteriology, Instituto Adolfo Lutz, Av. Dr Arnaldo, 355, 01246-902 São Paulo, SP, Brazil.
authors: Rosangela
authors: R
authors: Siqueira de Oliveira
mesh_terms: D000942:Antigens, Bacterial / Q000302:isolation & purification; D006801:Humans; D007753:Laboratories / Q000592:standards*; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology*; D013997:Time Factors; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000382:microbiology
chemical_list: D000942:Antigens, Bacterial; C510537:MPT64 protein, Mycobacterium tuberculosis