Mycobacterium tuberculosis complex is not detected by DNA amplification assay in sputum specimens of patients with lung scars due to past pulmonary tuberculosis.
OBJECTIVE
To evaluate detection of false-positive sputum amplification assay results in former tuberculosis patients with residual pulmonary scars.


METHODS
A total of 268 sputum specimens from 25 war veterans with tuberculosis during 1940-1959, without adequate chemotherapy, and 19 subjects effectively treated for cavitary tuberculosis during 1980-1993 were tested by smear, culture and DNA amplification, as were 34 controls with no history of tuberculosis or pulmonary scars.


RESULTS
No active tuberculosis cases were identified. All specimens were negative on DNA amplification and smear. Eight specimens from six subjects were positive on culture, revealing atypical mycobacteria.


CONCLUSIONS
No genetic Mycobacterium tuberculosis material in sputum specimens of subjects with residual lesions of pulmonary tuberculosis and no false-positive amplification results were detected.
Rajalahti
I
I
Department of Pulmonary Diseases, Tampere University Hospital, Tampere, Finland. iiris.rajalahti@nic.fi
Vuorinen
P
P
Järvenpää
R
R
Nieminen
M M
MM
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000302:isolation & purification*; D011859:Radiography; D013183:Sputum / Q000382:microbiology*; D014397:Tuberculosis, Pulmonary / Q000000981:diagnostic imaging*