title: Acid-fast staining of urine and gastric contents is an excellent indicator of mycobacterial disease.
abstract: It is a commonly held opinion that acid-fast staining of urine or gastric aspirates is not a reliable indicator of mycobacterial disease because of the presence of saprophytic mycobacteria. In order to determine the clinical usefulness of acid-fast staining of these body fluids, we reviewed our 10-yr experience with acid-fast stains. Forty-seven of 5,829 urine specimens (0.8%) and 39 of 309 gastric aspirates (12.6%) yielded mycobacteria on culture. Twenty-three urine specimens and 12 gastric aspirates had positive acid-fast stains. Of these, only one possible false positive acid-fast stain of urine (less than 1%) was found and none was found in gastric aspirates. Thus, acid-fast stains of urine and gastric aspirates are, when positive, reliable indicators of true mycobacterial disease.
mesh_terms: D001431:Bacteriological Techniques; D005766:Gastrointestinal Contents; D006801:Humans; D009164:Mycobacterium Infections / Q000382:microbiology*; D009165:Mycobacterium Infections, Nontuberculous / Q000382:microbiology; D011237:Predictive Value of Tests; D013194:Staining and Labeling / Q000379:methods; D014376:Tuberculosis / Q000382:microbiology; D014556:Urine / Q000382:microbiology*