[Detection of Mycobacterium tuberculosis in sputum using PCR and chemoluminescent display].
BACKGROUND
Polymerase chain reaction (PCR) using a probe with revealed chemoluminescence applied to the rapid diagnosis of pulmonary tuberculosis was used to detect Mycobacterium tuberculosis in sputum samples.


METHODS
The sputum samples were treated with proteinase K, SDS, NaOH and CTAB. A fragment of the IS6110 sequence of Mycobacterium tuberculosis detected by a probe marked with digoxigenin and revealed chemoluminescence was amplified.


RESULTS
The detection limit of the technique was situated at 10 mycobacteria per sample. Of 120 samples with a positive culture, 88 were positive by chemoluminescence probe (73.3%). The sensitivity decreased to 68.6% (35/51) in samples with negative staining and positive culture.


CONCLUSIONS
The application of molecular biology techniques are a good diagnostic alternative in samples with negative staining and clinical suspicion of tuberculosis. Our system is a cheaper alternative than the commercial systems and is applicable in laboratories unable to use radioactive isotopes.
Rodríguez
J C
JC
Laboratorio de Microbiología, Hospital General Universitario de Elche, Universidad de Alicante.
Fuentes
E
E
Royo
G
G
D001431:Bacteriological Techniques / Q000191:economics; D004269:DNA, Bacterial / Q000302:isolation & purification; D004076:Digoxigenin; D006801:Humans; D008163:Luminescent Measurements; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000191:economics / Q000379:methods*; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology*; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000382:microbiology
D004269:DNA, Bacterial; D004076:Digoxigenin