Affiliations: Research Center Borstel, Clin. and Exp. Pathology,
Parkallee 1-40, D-23845 Borstel | Research Center Borstel, National Reference Center for
Mycobacteria, Parkallee 1-40, D-23845 Borstel
Note: [] Address for correspondence Dr. T. Goldmann Research Center
Borstel Clin. & Exp. Pathology Parkallee 3 D-23845 Borstel E-mail:
[email protected]
Abstract: PCR is a unique technology for sensitive detection of mycobacterial
DNA-sequences in cases where no fresh material for classical analyses can be
obtained. We describe the set up of an optimized protocol and our experience of
154 cases analyzed during the last two years. In 35,7% of the cases the quality
of the extracted DNA had been too low to obtain any information. In 33,8% of
the cases with suitable DNA we did not amplify mycobacterial DNA. In 30,5% of
the cases we detected mycobacterial DNA: 63,8% of those belonged to the M.
tuberculosis-complex and 36,2% were non-tuberculous mycobacteria (NTM).
Fragmentation of the DNA extracted from clinical samples on the one hand and
the rigid cell wall of mycobacteria on the other hand are obstacles to detect
the DNA of these micro-organisms by PCR in paraffin-embedded tissues. The
introduction of heat / cold treatments during DNA-extraction improved the
detection of mycobacterial DNA by breaking the mycobacterial cell walls
although contributing to further DNA-fragmentation. Within its limitations,
like the quality of DNA from paraffin embedded specimens and the large efforts
necessary to control contaminations, PCR represents a powerful additional tool
for routine diagnostics of mycobacterial infections.
