Urine and Body Fluid Analysis Automation

Explain the principle of reflectance photometry.

Compares the amount of light reflected with that of known concentrations and then display or print concentration units or transmit data to a laboratory in formation system (LIS).

Measuring the intensity of the reflected light at specific wavelengths, and using this data to determine characteristics like color, concentration of substances, or the physical properties of the material. 

Differentiate between semiautomated urine chemistry analyzers and fully automated urine chemistry analyzers.

Semiautomated

• Test for the chemical components of urine from a reagent dip stick.

• The semiautomated instrument requires the operator to:

  • 1. Dip the reagent strip into a urine sample that has been mixed well.

  • 2. Blot the strip to remove excess urine.

  • 3. Place the strip onto the reagent strip platform.

  • 4. Press the analyze/enter button

• Results are printed

Fully automated 

• Designed for a high-volume urinalysis laboratory with user walk-away capability.

• Flow cytometry and digital imaging techniques are technology used for urine sediment analysis

State the advantages of automated microscopy methods over manual microscopy methods for analyzing urine sediment

• Increased TAT’s (1 min vs 6 min manually)

• Cost effective

• Manual microscopy is not easily standardized because of the high variation among operators even in the same facility.

4.Describe laser-based flow cytometry, digital imaging, and auto particle recognition technologies used in automated urine microscopy analyzers.

• Flow cytometry coupled with a blue semiconductor laser to measure particle length, particle volume, particle internal complexity, and total amount of nucleic acid contained within the particle

• Auto particle recognition (APR): The Capability of some equipment to categorize and count urine particles automatically in uncentrifuged urine based on size, shape, texture, and contrast

• Digital imaging: system designed to capture detailed images of urine particles in urine samples that require further review. All captured urine particle images are classified, based on size, into eight different classes.

Discuss the advantages of automated body fluid analyzers over the Neubauer hemocytometer for body fluid cell counts.

• Hemocytometer procedures are labor-intensive and time-consuming, and often they are subject to technologist variability.

• Automation brings quality control, precision, faster TATs, and standardization of results10 to a method that previously was uncontrolled.

All of the following are automated methods for urine clarity EXCEPT?

Refractive index

Which of the following would be a "flagged" particle requiring review from an automated microscopic exam?

transitional epithelial cell

Which of the following methods is used to measure specific gravity in automated urinalysis?

refractive index

What is an advantage to semiautomated urinalysis instrumentation?

results are corrected for urine color

Which of the following is considered waived testing under CLIA guidelines?

semiautomated urinalysis