Abstract
[Objective] Genetic testing using formalin-fixed paraffin-embedded (FFPE) sections is hardly carried out in clinical laboratories because the nucleic acid extraction process is very complicated and time-consuming. We have found that nucleic acid extraction using zirconia beads (beads method) is useful for the detection and identification of Mycobacterium spp. from FFPE sections by polymerase chain reaction (PCR) analysis. [Methods] Eleven samples that were found to be positive for Mycobacterium tuberculosis (MTB), Mycobacterium avium (MAV), and Mycobacterium intracellulare (MIN) by the culture and Z-N stain methods and 35 samples that were found to be negative by the culture and Z-N stain methods were extracted by the column method for the detection of MTB, MAV, and MIN by PCR analysis. The same samples pretreated by the beads method were also detected by the same PCR analysis. [Results] In the column method, MTB was detected in 5 of 7 MTB-positive samples, MAV in 2 of 2 MAV-positive samples, and MIN in 1 of 2 MIN-positive samples. MTB and MAV were not detected in 34 of 35 MTB- and MAV-negative samples, and MIN was not detected in all MIN-negative samples. In the beads method, MTB was detected in 6 of 7 MTB-positive samples, and other results were similar to those of the column method. Measurement times were 160 min for the column method and 70 min for the beads method. [Conclusion] This study shows that PCR analysis using the beads and column methods is useful for detecting and identifying Mycobacterium spp. from FFPE sections.
