Sensitive identification of mycobacterial species using PCR-RFLP on bronchial washings.
In 98 patients (24 with active pulmonary tuberculosis [TB] lesions, 28 with cured TB lesions, and 46 with nontuberculous opacities [control group] in chest CT scans), we examined whether washing the bronchus after brushing the lesion, then applying polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to the bronchial washings might be useful for diagnosing TB and nontuberculous mycobacteriosis (NTMosis). After biopsy and brushing with a bronchoscope, the bronchus connecting to the lesion was washed with 20 ml saline. The saline used for washing the brushes (5 ml; brushing sample), and 3 to 10 ml saline aspirated through the forceps channel (washing sample) were examined by PCR-RFLP, which proved able to identify Mycobacterium tuberculosis and seven species of nontuberculous mycobacteria (NTM). The values obtained for the sensitivity of the PCR-RFLP with respect to the brushing sample, the washing sample, and both samples mixed together were 70, 76, and 91%, respectively, when only patients who were culture-positive or radiologically improved after antituberculous therapy were considered as showing true infection. A mixture of brushing and washing samples provides useful material for PCR and culture, and the PCR-RFLP used here is a good method for the simultaneous identification of several species of mycobacterium (including M. tuberculosis).
Hidaka
E
E
Departments of Laboratory Medicine and Internal Medicine, Shinshu University School of Medicine, Matsumoto, Japan.
Honda
T
T
Ueno
I
I
Yamasaki
Y
Y
Kubo
K
K
Katsuyama
T
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015269:Mycobacterium avium Complex / Q000235:genetics; D015270:Mycobacterium avium-intracellulare Infection / Q000175:diagnosis / Q000382:microbiology; D009169:Mycobacterium tuberculosis / Q000235:genetics; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011237:Predictive Value of Tests; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000382:microbiology