Standardization of in-house polymerase chain reaction for the identification of Mycobacterium tuberculosis at the reference Tropical Disease Hospital in the State of Goiás, Brazil.
This study compares smear, growth in Lowenstein-Jensen medium, and in-house polymerase chain reaction (PCR) techniques for the detection of Mycobacterium tuberculosis. A total of 72 specimens from 72 patients with clinical symptoms of tuberculosis, including 70 sputum and two bronchial aspirate samples, were tested in parallel by smear, culture, and in-house PCR techniques. From these, 48 (66.6%) were negative by the 3 methods, 2 (2.8%) were smear positive and negative by culture and in-house PCR, 11 (15.3%) were both smear and culture negative, and in-house PCR positive, 7 (9.7%) were positive by the 3 methods, 2 (2.8%) were positive by smear and culture, and negative by PCR, 2 (2.8%) were positive by culture and PCR, but smear negative. After the resolution of discrepancies in PCR results, the sensitivity and specificity for in-house PCR technique to M. tuberculosis relative to the culture, were 81.8% and 81.9%, respectively. These results confirm that this method, in-house PCR, may be a sensitive and specific technique for M. tuberculosis detection, occurring in both positive and negative smear and negative cultures.
Departamento de Microbiologia, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, 74605-050, Goiânia, GO, Brazil. malves@iptsp.ufg.br
Márcia Alves Vasconcelos
MA
Rodrigues
Alvaro Bisol
AB
Serafini
Marieta de Souza
Mde S
Pereira
Thathiane Dias
TD
da Silva
Marcelo Fouad
MF
Rabahi
Suely Lemes de
SL
Alves
André
A
Kipnis
D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology; D003470:Culture Media; D004269:DNA, Bacterial / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods* / Q000592:standards; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*
D003470:Culture Media; D004269:DNA, Bacterial