title: Clinical evaluation of the Lumac bioluminescence method for screening urine specimens.
abstract: A bioluminescence method for screening urine cultures to provide rapid reporting of negative specimens and to select appropriate urine cultures for direct application of automated identification methods was evaluated. A total of 2,000 specimens were processed in the Lumac Biocounter (3M, St. Paul, Minn.), and the results were compared with quantitative culture techniques by using a 0.001-ml inoculating loop. A total of 841 specimens were positive by the bioluminescence method; 291 specimens were culture positive (greater than or equal to 50,000 CFU of one or two organisms per ml). Positive cultures represented more than 20 different organisms. Approximately two-thirds of the false-positive results represented mixed flora or pure cultures of less than 5 X 10(4) organisms per ml. The predictive value of a negative result was 98.4%, reflecting a false-negative rate of only 0.7%. No advantages in cost or technician time were noted, but the Lumac method appears to be a useful technique in decreasing reporting time, especially for negative urine cultures.
mesh_terms: D001437:Bacteriuria / Q000175:diagnosis*; D005069:Evaluation Studies as Topic; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000302:isolation & purification; D006801:Humans; D008163:Luminescent Measurements; D011933:Reagent Kits, Diagnostic
chemical_list: D011933:Reagent Kits, Diagnostic