A comparison of methods for collecting clean-catch urine specimens in a clinic population of obstetric patients

Abstract

A descriptive study comparing the use of the gram-positive skin cleansers Zephiran and hexachlorophene to Prepodyne, a gram-negative cleanser, was performed upon 1,469 specimens from patients attending the prenatal clinic of a large university hospital. The period prevalence rate of symptomatic and asymptomatic bacteriuria in 1,350 patients was 11.5 per cent. Group teaching compared to individualized teaching of the patients to collect their own aliquots did not appear to have a measurable effect upon the levels of bacteriuria. Significant differences were found at p = 0.05 between all the serially sampled groups using the different cleansers. No significant differences was found between the two groups using only hexachlorophene when compared for differences between patient-collected and nurse-collected specimens; nevertheless, the patient-collected specimens had greater proportions of low bacterial counts than those collected by the nurses. This study indicates that carefully instructed patients in large clinic populations are more efficient than the nurses when they collect their own midstream specimens, using an adequate cleansing agent. An analysis of the rates disclosed that Zephiran cleansing had high contamination levels, whereas Predodyne significantly reduced contamination of the specimens. However, the possible reduction of the rate of 105 specimens to 9.1 per cent in the group using Prepodyne did not rule out the possibility of reduced specificity, and the hazard of false-negative results occurring with the use of gram-negative skin cleansers requires further study.