Contaminant acid-fast bacilli (AFB) on tissue section slides can usually be identified as such, because they're outside of the plane of the tissue section.
The organism is a nearly non-pathogenic AFB called Mycobacterium gordoneae or Mycobacterium aquae. The problem affects both fluorescent and the old (and obsolete) light microscopic techniques. This problem underlines the importance of histotechnologists' knowing how to interpret special stain control slides. I don't recall ever having seen a publication directed at histotechnologists that clearly explained how to identify acid-fast bacilli in tissue sections. Bob Richmond Samurai Pathologist Knoxville TN _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet