Question | Answer |
After receiving a 24-hour urine for quantitative total protein analysis, the technician must first: | Measure the total volume. Measure total volume of the sample before removing an aliquot. To calculate total protein, measure the protein of an aliquot to find the mg/dL, then multiply that answer by the number of dL in the 24-hour collection. |
False results in urobilinogen testing may occur if the urine specimen is: | Exposed to light. Urobilinogen is degraded by light. |
A clean-catch urine is submitted to the laboratory for routine urinalysis and culture. The routine is done first, and 3 hours later, specime is sent to the micro lab for culture. The specimen should: | Be rejected due to the time of delay. Ideally, the culture is set up first to prevent contamination. If that is not feasible timewise, the sample should be aliquoted using asceptic technique and refrigerated till cultured. |
Which of the following urine results is most apt to be changed by prolonged exposure to light? | Bilirubin. Bilirubin is degraded by light. |
Urine samples should be examined within 1 hour of voiding because: | Bacterial contamination will cause alkalinization of the urine. |
A urine specimen comes to the lab 7 hours after it is collected. It is acceptable for culture only if the specimen has been stored: | at 4-7 degrees celsius. |
Which of the following would be affected by allowing a urine specimen to remain at room temperature for 3 hours before analysis? | pH. pH is affected by metabolism of the urine components by bacteria, and room temperature is warm enough for this to occur. |
Failure to observe RBC casts in a urin specimen can be caused by: | centrifuging an unmixed specimen. Larger sediment sinks to the bottom. W/o mixing, sediment in container may not be poured into the centrifuge tube. |
The creatinine clearance is reported in: | mL/min. This is the filtration rate, and is reported in minutes. The sample is a 24-hour urine, which is entered into the calculation as the volume in mL, and the factor of 1440 min/24-hours is applied. |
Microalbumin can be measured by a random urine collection. An increased microalbumin is predictive of: | Nephropathy. Detection of small amounts of albumin predict eventual kidney disease. The advantage of theis sensitive detection is that patients with microalbuminuria can be tx w/ anti-hypertensive meds and followed up more intensely to delay nephropathy. |