title: Diagnostic value of the Amplicor PCR assay for initial diagnosis and assessment of treatment response for pulmonary tuberculosis.
abstract: We evaluated the Amplicor PCR assay as an initial diagnostic tool on the basis of clinical diagnosis, and assessed this assay as a follow-up test for patients with pulmonary tuberculosis during chemotherapy. Of the 208 specimens from 155 patients who were bacteriologically and/or clinically diagnosed with active tuberculosis before chemotherapy, 144 were Amplicor PCR-positive (sensitivity, 69.2%), which was equal to the results of culturing. Among 89 specimens which showed positive results by smear and culturing, the Amplicor PCR assay detected 87 (97.8%), whereas among 55 specimens which showed smear-negative but culture-positive results, the Amplicor PCR assay detected 46 (83.6 %)(P= 0.003). No false positive results were found in the two systems (specificity, 100%, 120/120). The Amplicor PCR assay was also evaluated as a follow-up test using 926 specimens from 207 patients receiving active tuberculosis chemotherapy. Among 433 specimens which showed Amplicor-PCR positive, 222 (51.3%) were culture-negative. On the other hand, among 233 culture-positive specimens, only 12 (5.2%) were Amplicor PCR-negative. Therefore, this assay is useful for the rapid diagnosis of tuberculosis. The duration of Amplicor PCR-positive after culture-negative conversion was significantly associated with the presence of cavitary lesion, smear-positive specimens before treatment, and smear-positive specimens with negative cultures during chemotherapy.
authors.affiliation: Department of Internal Medicine, Chubu National Hospital, Obu, Aichi, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Iinuma
authors.forename: S
authors.initials: S
authors.lastname: Ichiyama
authors.forename: S
authors.initials: S
authors.lastname: Yamori
authors.forename: J
authors.initials: J
authors.lastname: Oohama
authors.forename: N
authors.initials: N
authors.lastname: Takagi
authors.forename: Y
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: K
authors.initials: K
authors.lastname: Shimokata
authors.forename: N
authors.initials: N
authors.lastname: Nakashima
mesh_terms: D000995:Antitubercular Agents / Q000627:therapeutic use*; D003470:Culture Media; D005189:False Positive Reactions; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology; D016896:Treatment Outcome; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000188:drug therapy*
chemical_list: D000995:Antitubercular Agents; D003470:Culture Media; D011933:Reagent Kits, Diagnostic