Subject(s)
Bacteriuria/diagnosis , Indicators and Reagents , Reagent Strips , Female , Gentian Violet , Humans , Male , Phenazines , Staining and LabelingABSTRACT
The Lumac system, which assays bacterial ATP by bioluminescence, is a rapid method (less than 1 hour) for detection of bacteriuria. Conventional culture by calibrated loop technic and the Lumac system were compared using 2,000 urine specimens. Interpretation of Gram's stains of uncentrifuged specimens in addition to results of the Lumac system provided a second comparison with culture. Using a criterion of greater than or equal to 10(4) CFU/mL, conventional culture yielded 17% of the 2,000 specimens positive for bacteriuria. By Lumac + smear 27% were positive opposed to 41% positive by the Lumac system alone. The Lumac + smear method produced sensitivity (97%), specificity (88%), positive predictive value (62%), and negative predictive value (99.3%). False negative rates by the Lumac alone and Lumac + smear were 0.65% and 0.5%, respectively.
Subject(s)
Bacteriological Techniques , Bacteriuria/diagnosis , Adenosine Triphosphate/urine , Adult , False Negative Reactions , False Positive Reactions , Female , Humans , Luminescent Measurements , Staining and Labeling , Stem Cells/analysisABSTRACT
Automated radiometric technic (BACTEC Johnston Laboratories, Towson, MD) was compared with conventional mycobacterial culture procedure (Lowenstein-Jensen plus Gruft modification of Lowenstein-Jensen) in this study of 1,000 clinical specimens. In addition, 8-azaguanine inhibition was tested by radiometric technic as a rapid procedure for the differentiation of Mycobacterium tuberculosis from other mycobacterial species. A total of 59 mycobacteria was recovered. Of 28 clinically significant isolates (M. tuberculosis, M. kansasii, M. avium, M. fortuitum), the BACTEC system detected 26 (93%). Conventional methods recovered 23 (82%). The BACTEC system required an average of seven days to recover M. tuberculosis from smear-positive specimens compared with 18 days required by Lowenstein-Jensen or Gruft slants. From smear-negative specimens, the BACTEC detected M. tuberculosis in an average of 20 days versus 28 days by conventional procedure. All 20 isolates of M. tuberculosis were inhibited by 8-azaguanine, whereas 39 isolates of mycobacteria other than M. tuberculosis were not inhibited. The BACTEC system accomplishes more rapid recovery of mycobacteria and provides a higher yield than conventional methods.
Subject(s)
Mycobacterium tuberculosis/isolation & purification , Radiometry/methods , Bacteriuria/diagnosis , Body Fluids/microbiology , Humans , Suppuration/microbiologyABSTRACT
Diagnosis of Campylobacter enteritis by direct smear examination of stool specimens, using 1% aqueous basic fuchsin, was compared with a conventional cultural method (Campy-BAP). After examination of 485 stool specimens the direct smear method produced a sensitivity and specificity of 94% and 99.5%, respectively.
