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Biology LibreTexts

Urine Luck! - Using Urine as a Diagnostic Tool

  • Page ID
    19899
  • Objective:

    Examine urine samples from patients and suggest a diagnosis and treatment plan based on test results. Urinalysis is the analysis of urine using physical and chemical means to test for the presence of disease, drugs, or other health states in in individual.

    In this investigation, you will use simulated urine and perform a variety of tests to develop a diagnosis for a fictional patient.

    If the urine is... What it could indicate is...
    Color Dark yellow dehydration or fever
    Pale light yellow

    patient drank a lot of liquids prior

    diabetes

    Odor Red with blood damage to kidneys
    Fruity the presence of ketones (breakdown of fats), which is a product of diabetes or starvation, or specific type of diet (Atkins)
    Transparency Foul the presence of bacteria
    Clear normal urine samples appear clear/transparent
    Cloudy

    old samples could appear cloudy if bacteria has had time to grow

    fresh samples could appear cloudy if a urinary tract infection (UTI) is present, or if there are blood cells or pus in the urine

    Presence of Substances
    Sugar

    Test with Benedict’s solution and hot water bath

    Blue → orange means sugar is present

    High amounts of sugar in diet or in recent meal

    diabetes

    Protein

    Test with Biuret Reagent

    Blue → purple means protein is present

    an abnormal condition called proteinuria, that results from damage to kidneys; can also be caused by diabetes or high blood pressure

    Human Chorionic Gonadodotropin hCG

    Test with Indicator Strips

    Color change to blue indicates hCG is present

    Pregnancy if female, possible testicular cancer in males
    Ketones Test with indicator strip, color change to pink or red indicates ketones in urine

    High protein diet, such as Atkins diet

    Starvation or diabetes can cause the body to burn fat for energy, releasing ketones

    Procedure for Urinalysis

    You will receive a urine sample and a patient chart for one of five possible patients in the office. Record your patient number and the results of each test in the chart.

    Physical Observations

    1. Observe and describe the color, odor, and transparency of the four urine samples. Record physical observations.

    1. Get approval from teacher before advancing.

    Chemical Observations

    1. To test for sugar, add approximately 6 ml of the Benedict’s solution to one test tube and 10 ml of the urine sample. Place the sample in a hot water bath and observe the color after five minutes. If the color has turned orange, that indicates the presence of sugar in the urine.

    1. To test for protein content, add approximately 2 ml of the Biuret reagent to 10 ml of the urine sample. It does not need to be placed in a water bath. If the bright blue color changes to purple, protein is present in the urine.

    1. To test for hCG, use a test strip provided and dip into a small sample of urine from your patient, a color change to blue indicates the presence of hCG.

    1. To test for ketones, use a test strip provided and dip into a small sample of urine from your patient, a color change orange-red or yellow indicates the presence of ketones.

    Urinalysis Results for Each Patient:

    You only need to do your assigned patient.

    Patient 1 Patient 2 Patient 3 Patient 4 Patient 5
    Color
    Odor
    Transparency
    Presence of Sugar
    Presence of Protein
    Presence of hCG
    Presence of Ketones

    Analysis and Diagnosis (CER)

    CLAIM: Write a statement that includes a diagnosis for your patient.





    EVIDENCE: Provide evidence that supports your diagnosis using data you gathered during the lab. This is a summary of your important findings that support the diagnosis (claim) that you wrote.






    REASONING: Provide an explanation of why the evidence supports the claim (why the results support the diagnosis?). Include specific medical and anatomical terminology to explain why a particular result would indicate the problem in the patient.






    Treatments: Provide recommendations for how to solve the problem indicated by the diagnosis. You may need to refer to your text or other resources.

    Accomplished (3) Proficient (2) Developing (1)
    CLAIM Makes an accurate and complete claim, uses complete and grammatically correct sentences Makes an accurate, but incomplete claim, or grammatically incorrect Claim is not accurate, incomplete, or unintelligible
    EVIDENCE Provides appropriate and sufficient evidence to support claim by referencing specific data, observations, or text evidence (for readings) Provides appropriate data but insufficient data, too general or lacking in details Provides evidence but it is insufficient, inaccurate, no details
    REASONING Provides thorough reasoning that links evidence to the claim, references scientific principles that are relevant to claim Provides reasoning that links evidence to the claim, lacks scientific principles Does not provide reasoning, or reasoning does not link evidence.
    Treatment Evidence of research to provide a typical treatment plan aligned to the patient diagnosis Treatment plan is included, but not thorough or does not fully address patient’s problem Treatment is not is inaccurate or incomplete

    Patient 1: Martin Manoogie

    Chief Complaint: Patient has been urinating frequently, often waking up at night to go to the bathroom. He reports feeling thirsty all the time and has a decreased appetite.

    History: Patient is a 34 year old male who is 5’10” and weighs 240 lbs. There is no major family history or heart disease, cancer, or diabetes. Patient also reports minor shortness of breath when doing minor exercise, like climbing stairs. Patient reports drinking alcohol “in moderation” and is a non-smoker.

    Current medications: Patient is taking medically prescribed diet pills to lose weight.

    Past Health: Patient had surgery at the age of 22 years to repair torn cartilage in the knee. Tonsils were removed at age 10.

    Personal History: Mr. M works in the IT department of a major company. He is not married and lives with his mother. Household has four cats.

    Physical Exam:
    Temperature: 98.6
    Pulse: 68 bpm
    Blood pressure: 158/80

    Patient 2: Amy Bailey

    Chief Complaint: Patient reports frequent urination and abdominal pain. She feels like even after urinating, she still need to go to the bathroom.

    History: Amy is a 21 year old female, weighing 130 lbs and is 5’5” tall. There is no major family history or heart disease, cancer, or diabetes. Amy is a non-smoker who drinks socially.

    Current medications: Amy is on birth control pills.

    Past Health: Amy had her tonsils removed at the age of 10, and had a miscarriage at the age of 18.

    Personal History: Amy is a college student, studying to become a veterinarian, she lives in a dorm with two roommates.

    Physical Exam:
    Temperature: 101.8
    Pulse: 62 bpm
    Blood pressure: 120/65

    Patient 3: Roshanda Kim

    Chief Complaint: Patient is having trouble sleeping at night and is urinating more frequently than normal.

    History: Roshanda is a 30 year old female, weighing 180 lbs and is 5’5” tall. There is no major family history or heart disease, cancer, or diabetes. Roshanda recently quit smoking and is using nicotine patches.

    Current medications: Nicotine supplements

    Past Health: Roshanda has a C section 8 years ago, baby boy was born healthy and recovery was normal for R.

    Personal History: Roshanda is planning to get married in June and is trying to lose weight. She is using the Atkins diet plan, which is a high protein diet and reports she has lost 10 pounds in the past 3 weeks.

    Physical Exam:
    Temperature: 98.9
    Pulse: 78 bpm
    Blood pressure: 130/70

    Patient 4: Enzo Marin

    Chief Complaint: Loss of appetite, frequent and painful urination

    History: Enzo is 14 years old and is involved in swimming, and baseball. Mother reports Enzo used to be very active, but has been feeling tired and run down and isn’t eating well.

    Current medications: None

    Past Health: Enzo experienced ear infections as a young child.

    Personal History: Enzo lives with both parents and a dog, he walks to school every day and practices with the baseball team after school. In past years, he was rarely sick, but he is falling behind in school this year due to feeling sick and staying home. Parents and coaches are concerned.

    Physical Exam:
    Temperature: 99.5
    Pulse: 58 bpm
    Blood pressure: 122/65

    Patient 5: Lori Grimes

    Chief Complaint: Loss of appetite, nausea and general fatigue

    History: Lori is 25 years old, 5’10” and weighs 160 pounds. No family history of heart disease, cancer, or diabetes.

    Current medications: Birth control pills

    Past Health: Lori had her appendix removed at the age of 18.

    Personal History: Lori is married and lives with her husband and two dogs. She is an elementary school teacher.

    Physical Exam:
    Temperature: 98.4
    Pulse: 70 bpm
    Blood pressure: 118/56

    Instructor Notes

    Test Strips for Ketones and Pregnancy are simulated using pH paper and changing the recipe to make it more acidic or alkaline.

    I assign each group a different patient, though you could have them do all the patients, that process may take a while and you’ll need a lot more materials. The recipes described below can be tweaked, sometimes I add a splash of coffee to darken the urine up because yellow food coloring looks to bright to be real urine. I create a large amount in 1 liter containers and then parse them out in specimen containers. I have a few fancy containers purchased from Amazon that look like the specimen jars seen in doctor’s offices, but beakers or jars also work.

    You will need beakers, test tubes and hot water bath to do the Benedict’s test for sugar. Alternatively, you could order glucose test strips, but they are expensive.

    Test each sample for desired results. Because using pH strips for ketones and pregnancy, there might be unexpected results. Ketones present in urine is not necessarily a problem and can be based on diet. Only patient 5 should have an alkaline (basic) positive test.

    Urine Recipe

    Results

    Patient 1 Apple juice + water

    Color: yellow
    Fruity smell
    Sugar +
    Protein -
    hCG -
    Ketones + or - (depends on acidity of apple juice)

    Patient 2

    Water + yellow food coloring

    + milk to create cloudy appearance

    + ammonia or vinegar to create foul odor

    Color: yellow
    Odor: foul
    Sugar -
    Protein -
    hCG -
    Ketones - or +

    Patient 3 Water + yellow food coloring + a drop of sodium hydroxide (makes solution alkaline)

    Color: yellow
    Odor: normal
    Sugar -
    Protein -hCG -
    Ketones +

    Patient 4

    Water + yellow food coloring + egg beaters

    +red food coloring to simulate blood

    Color: yellow/red
    Odor: normal
    Sugar -
    Protein +
    hCG -Ketones -

    Patient 5 Water + yellow food coloring + a drop of HCL to make solution acidic

    Color: yellow
    Odor: normal
    Sugar -
    Protein -
    hCG +
    Ketones -