Reagent strip screening for sediment abnormalities identified by automated microscopy in urine from patients suspected to have urinary tract disease.

We assessed the ability of reagent strip screening to predict the finding of blood cells and bacteria using an automated urinalysis workstation (The Yellow IRIS, International Remote Imaging Systems, Chatsworth, Calif) in 427 specimens submitted for urine culture. The sensitivities of leukocyte esterase, hemoglobin, and nitrite detection on reagent strips were 71.9%, 70.8%, and 56.7%, respectively, at 5 or more white blood cells per high-power field, at 3 or more red blood cells per high-power field and bacteria observed using the IRIS. Screening results for leukocyte esterase associated with negative results using the IRIS for white blood cells represented mostly false-positive screening test results based on chart review. Positive screening test results for hemoglobin associated with negative results obtained with the IRIS for red blood cells consisted of equal numbers of false-positive screening test results and IRIS test results based on chart review. A common screening algorithm using a combination of these three reagent strip variables exhibited a false-negative rate of 30.1%: review of medical records found clinical evidence of urinary tract infection in 14 patients and genitourinary or renal disease or hypertension in another 13 patients. Adding more variables to the algorithm increases the sensitivity and decreases the specificity. Both microscopic examination and reagent strip testing of urine are necessary for the detection of abnormalities associated with disease.

Evolving approaches to management of quality in clinical microbiology.

Quality management in clinical microbiology began in the 1960s. Both government and professional societies introduced programs for proficiency testing and laboratory inspection and accreditation. Many laboratory scientists and pathologists were independently active and creative in expanding efforts to monitor and improve practices. The initial emphasis was placed on intralaboratory process. Later, attention was shifted to physician ordering, specimen collection, reporting, and use of information. Quality management in the laboratory depends in large part on the monitoring of indicators that provide some evidence of how laboratory resources are being used and how the information benefits patient care. Continuous quality improvement should be introduced. This consists of a more thorough assessment of doing the right things versus the wrong things in terms of customer demand and satisfaction and studying the cumulative effect of error when responsibility is passed from one person to another. Prevention of error is accomplished more through effective training and continuing education than through surveillance. Also, this system will force more conscious attention to meeting the expectations of the many customers that must be satisfied by laboratory services, including patients, physicians, third-party payers, and managed-care organizations.