Urine screening with the MS-2.

A study was undertaken to evaluate the effectiveness of the MS-2 (Abbott Laboratories, Dallas, Tex.) in screening urine specimens in a large clinical laboratory. A total of 15,319 urine specimens (9,954 midstream specimens and 5,365 catheter specimens) were evaluated with the MS-2 and by a surface streak procedure. The study was conducted in two phases, differing in that phase II urine specimens were evaluated in the MS-2 by using a program software update (03.01). For midstream urine specimens, MS-2 detection rates in phases I and II were, respectively, 94.5 and 94.3% at a plate count of greater than 10(5) CFU/ml, 74.4 and 65.3% at plate counts of 5 X 10(4) to 1 X 10(5) CFU/ml, 55.0 and 52.4% at plate counts of 1 X 10(4) to 5 X 10(4) CFU/ml, 31.2 and 20.5% at plate counts of 10(3) to 10(4) CFU/ml, and 15.7 and 6.4% at plate counts of less than 10(3) CFU/ml. For catheter urine specimens, the MS-2 detection rates in phases I and II were, respectively, 95.4 and 96.8% at plate counts greater than 10(5) CFU/ml, 74.4 and 85.7% at plate counts of 5 X 10(4) to 1 X 10(5) CFU/ml, 50.0 and 44.4% at plate counts 10(4) to 5 X 10(4) CFU/ml, 25.6 and 14.9% at plate counts of 10(3) to 10(4) CFU/ml, and 14.7 and 5.2% at plate counts less than 10(3) CFU/ml.