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-urine-

samples-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