U rinalysis Virtual Activity
lntrod uction
The use of human bodily fluids such as urine has been in the past commonly used in teaching labs’ This
practice has been severely restricted for various reasons, one being the potential for exposure to
infectious agents. There are alternatives to using actual bodily fluids for learning although they are not
often the best practice to learning disease infection and prevention or practicing the scientific method
and use of controls. The following is adapted from the Student Urinalysis and Analysis Activity Kit from
Carolina Biological Supply, 20i”7.
This virtual lab exercise on Urinalysis is designed to help understand some of the basics of using
biological samples compared to controls in determining an interpretation of real data. Urinalysis is used
by doctors to assess various factors of urine, including color and pH, that could indicate disease. These
factors are normally kept in balance by the kidneys as they filter blood and produce urine but may
change under certain conditions like disease or medication use, or even with certain foods. Table L
shows the urine colors and possible things that affect color change and potential disease associated with
the specific urine color (Carolina Biological Supply, 2017).
Table 1. Urine color and possible causes.
Normal urine colors range from light yellow to amber, depending upon the concentration of urobilin,
the urine pigment. Certain foods, drugs, diseases, and amount of water intake can cause lighter or
darker urine (Carolina Biological Supply, 2Ot7).
Color Diet Druss d isease
Light yellow to amber Normal None None
Clear to light yellow lncreased fluid intake Alcohol Uncontrolled diabetes
mellitus
Yellow orange to
orange
Carrots Antibiotics, pyridium Bilirubin from
obstructive jaundice
Green Green food dyes,
aspa ragus
Diuretics Bacterialinfection
Red to red brown Beets Senna laxatives Hemoslobin in urine
Dark wine Beets Anti-inflammatory
drues
Hemolytic jaundice
Brown Rhubarb (large
quantities)
Ba rbiturates Hemolytic anemia or
liver disease; extremely
strenuous exercise or
muscle iniurv
Brown-black Rhubarb (huge
q ua ntities), excessive
sorbitol consumption
Antidepressants Melanin pigment from
melanoma (rare)
Possible causes
Test result Diet Disease
Low pH (<6) High protein die! Cranberry
juice
Uncontrolled diabetes mellitus
Hieh pH (>8) Diet rich in vegetables; dairy
prod ucts
Severe anemia
Low specific gravity (<1.010) lncreased fluid i nta ke Severe renaldamage
High specific gravity (>1.026 Decreased fluid intake Uncontrolled diabetes mellitus;
severe anemia
Glucose present Laree meal Uncontrolled diabetes mellitus
Protein present High protein diet Severe anemia
Table 2. Abnormal urinalysis results and possible causes.
The pH of a solution is the measure of its free hydrogen ion (H+) concentration, which indicates acidity
or alkalinity. A solution with a pH of 7.0 is neutral. A solution with a pH of less than 7.0 is acidic and a
solution with a pH of greater than 7.0 is basic. Typically, the pH of normal urine is between 6.0 to 8.0.
Specific gravity is the density of a solution relative to water, which has a specific gravity of 1.000. The
specific gravity of normal urine ranges from 1.010-1..026. Specific gravity willvary according to fluid
intake but can also be affected by disease.
Glucose (sugar) should not be detected in normal urine; its presence usually indicates diabetes mellitus,
a severe metabolic disorder caused by defective carbohydrate utilization. The kidneys play a key role in
glucose homeostasis and are able to reabsorb practically all glucose in their proximal convoluted tubules
under normal conditions. lf blood glucose is too high, as in diabetes, the kidneys will be unable to
reabsorb all glucose, resulting in glucose presence in urine. Glucose may also be present in the urine
after a big meal or during times of emotional stress.
A very small amount of protein is normally present in the urine, Any change in the color of a protein test
strip indicates an elevated level of protein in urine. Diet and disease can affect protein levels in urine.
For example, patients with severe anemia, a condition where the blood lacks an adequate number of
red blood cells, usually excrete protein in their urine.
The procedure below was produced from artificial urine to develop two case studies: Case A clinical
history is of a male showing the need to void urine severaltimes in the night and a slow urine stream.
Urine color is typically amber with a specific gravity of 1.030. Microscopic analysis of the urine sample
indicated uric acid crystals; other blood results indicate elevated prostate specific antigen. Case B is a
woman with discomfort when passing urine. Urine color is yellow-orange and specific gravity is 1.026.
Use the information belowto interpret and write up a history of both patients. For each subject (Case A
and Case B), complete the tables using the information Figure L and compare to Tables l– 3. For results
that do not show a change from the control, report the test result as (negative). lf there is not a range of
values in the control (test result is 0 in the control table), any difference from the control is considered a
(positive) test result. lnvestigate using your Urine Lab Activity from the previous week, information in
this guide, and online sources; what normal and abnormal test results mean by writing a sentence in the
“interpretation of results” box on the tables and writing a brief one paragraph summary of the results
below each table.
Table 3. Control test results and interpretation of results.
Test Test result lnterpretation of the result
pH -6 Normal
Protein 0-150 me/dL Normal
Glucose 0-0.8 mmol/L Norma
Ketones 0 Norma
RBC <3 erythrocytes/uL Norma
WBC 0-L0 leukocytes/uL Norma
Hb 0 Norma
Nitrite 0 Norma
Color Yellow to amber Norma
Rrfrrencs edrrur sc*le Case.B
Figure L. Combur-7 Test @ strips for Case A and Case B dipped into artificial urine. lmage from
https://www. resea rchsate.net/figure/Figure-A3-l-Co mbur-7-TestR-strips-dioped-into-a rtificia l-urinesamples-for-Case-A-and fis3 319449195
Con*rol $trip Cxse A
(undipptd)
Table 4. Case A test results and interpretation of results.
Test Test result lnterpretation of the result
pH
Protein
Glucose
Ketones
RBC
WBC
Hb
Nitrite
Color
Specific gravity
1′ Briefly explain the significance of the results obtained. You should write a conclusion paragraph
of your overall findings.
2. Briefly explain the significance of the results obtained.
Table 5. Case B test results and interpretation of results.
Test Test result lnterpretation of the result
PH
Protein
Glucose
Ketones
RBC
WBC
Hb
Nitrite
Color
Specific gravitv
3. What is Cystitis? What typically causes this condition and how is it treated? Which subject (Case
A or Case B) might have this condition? Explain your reasoning.
4. Thinking about the urinary system in general, what do you think are the major concerns with the
urinary system as we age? Which subject (Case A or Case B) is likely showing signs of aging
based on the history? Explain your reasoning.
5. ln a clinical setting, urine is often examined under a microscope. What information about a
patient’s health might be gained through this type of examination? Which of the results from
the patient’s urinalysis would be verified using microscopic analysis? You might want to also
refer to your Urinary System Activity from the previous week.
5. Using Tables 1 and 2, fill in the table below the urinalysis results you would expect for someone
being treated for a bacterial infection like strep throat, assuming he or she follows the doctor’s
orders? What is your reasoning for each factor? The doctol’s orders are as follows: amoxicillin,
Lx/day; lots of bed resq drink lots of fluids.
7. As a pharmacist, what side effect warning related to the urinary system might you give someone
starting a new medication to treat the signs and symptoms of arthritis?
8, Can any of these urine tests definitively diagnose diabetes? Why or why not? lf not, why would a
doctor ever order urinalysis?
Factor Result Reasonins
Color
pH
Specific Gravity
Glucose
Protein
