RELEASES TOXIC FUMES!

Transcription

1 Name(s): Block: Date: Urinary System Lab Activity: Urinalysis Background: Urinalysis, the physical, chemical, and microscopic analysis or examination of urine can provide information about a person s carbohydrate metabolism (diabetes), kidney and liver function, acid-base balance, and urinary tract infections. Different measurements including specific gravity, ph, and the concentrations of several different components of urine are used in the diagnosis of different diseases. Some of the substances measured, such as protein or glucose, are rarely if ever present at detectable levels in the urine of a healthy person. Other parameters, such as specific gravity (a measure of total solutes distilled water has a specific gravity = 1) and ph, fluctuate over a wide range depending on diet, health status, and fluid intake. The table below presents expected normal urinalysis test values and explains the significance of each parameter measured. Note: The only parameters that are included in the chart are those used in today s lab. Property color turbidity odor glucose blood ph protein leukocytes Expected range / Significance of positive test (or abnormal range) light to dark yellow/ redness due to blood from glomerular injury, infections transparent, not cloudy (not turbid) / possible infection (presence of leukocytes) slightly aromatic, but not fruity or like acetone, no ammonia / ketosis, possible infection negative / possible diabetes mellitus negative/ inflammation/injury of urogenital tract or kidneys, menstrual contamination , normal or abnormal / continuously very urine may indicate acidosis; continuously very alkaline urine may indicate alkalosis or microbial infection negative-trace / excessive glomerular permeability, glomerulonephritis, sometimes due to advanced diabetes mellitus negative-trace / urinary tract infection Unfortunately, there was a mix-up at a nearby laboratory. Due to a back-up of samples at the lab that need to be re-tested, your class was selected to confirm the results that they obtained. You will be provided with five different urine samples and the results of your class s controlled tests. You will analyze those results and match them to the correct patients. Tests Performed: 1) ph paper color changes from orange depending on ph, key is on the side of package 2) Benedict s solution turns from blue to orange (when heated), if glucose is present 3) Biuret reagent turns from dark blue to pink/purple if protein is present - DO NOT HEAT - RELEASES TOXIC FUMES! 4) Silver nitrate forms a white precipitate in the presence of excess chloride ions 5) Urine color don t forget to observe the color and clarity of the sample

2 Patient Descriptions: Patient #1 Mr. Jones is 19 years old. He thought he just had the flu, until he noticed that he had the urge to urinate more frequently and that he was urinating in greater volumes than ever before. His urine also has a mildly sweet scent. When he went to see his doctor, he confessed to experiencing an increased appetite and great thirst, but has unexplained weight loss. Patient #2 Mr. Thompson is 60 years old and has been unusually tired for several weeks. He occasionally feels dizzy. Lately he finds it increasingly difficult to sleep at night. He has swollen ankles and feet, and his face looks puffy. He experiences a burning pain in his lower back, just below the rib cage. He also notices that his urine is dark in color. When he went to see his doctor last week, he was found to have elevated blood pressure and his kidneys were sensitive to pressure. Patient #3 Mr. Niguchi is 38 years old and has been feeling weak and excessively tired for the last two months. He also complains of dizziness when rising from a sitting or lying position. Although he spends very little time in the sun, he has developed these patches of hyperpigmentation resembling black freckles on his forehead, face, and shoulders. When he finally went to the health clinic last week, he was extremely dehydrated and required IV fluids. Patient #4 Mrs. Martinez is 46 years old. She has regular yearly checkups and has no visible symptoms. Her urine was submitted for a corporate drug test. Patient #5 Ms. Smith is 27 years old and has been experiencing a painful burning sensation during urination. She noticed that despite the pain, she felt like urinating more frequently and with more urgency. She also has a slight fever that has been going on for the past few days. Diseases: a) Addison s disease It is a secretory disorder of the adrenal cortex. It results in decreased output of aldosterone. This disease is also known as hypoaldosteronism. Aldosterone is a hormone that increases the reabsorption of sodium and water in the renal tubule. b) Diabetes mellitus It is a disorder of the pancreas. The pancreas either does not secrete enough insulin or functioning insulin. c) Chronic kidney failure It is caused by damage to the nephrons in the kidney by infection, physical trauma, toxic chemicals, or cardiovascular disease. d) Urinary tract infection It is microbial infection of the urethra. e) **There is one healthy patient.**

3 Test Results: Urine Sample Benedict s Solution Silver Nitrate A Orange No B No No C No No D No White precipitate E No No Biuret Reagent No Pink/Purple No No No ph basic Urine Color Light Yellow Cloudy/orange Cloudy/yellow Light yellow Yellow 1) Summarize the results of the glucose test and compare to expected values. 2) Summarize the results of the salt test. 3) Summarize the results of the protein test and compare to expected values. 4) Summarize the results of the ph test and compare to expected values. 5) Summarize the observations of urine color and compare to expected values. 6) Which patient is the control? How do you know? Explain. 7) Why is it important to perform tests on a normal urine sample?

4 8) Which patient has diabetes mellitus? What evidence supports your diagnosis? 9) Which patient has a urinary tract infection? What evidence supports your diagnosis? 10) Which patient has Addison s disease? What evidence supports your diagnosis? 11) Which patient has chronic kidney failure? What evidence supports your diagnosis? 12) Why is it important to perform multiple different tests to diagnose a disease?

5 13) What causes the chemical content of urine to change throughout the day? Cite a specific example. 14) Suppose a urine sample revealed abnormal results, such has an extremely high glucose level. Should a doctor make a diagnosis based on that test alone? Why or why not? Explain.

6 Patient Data Table: Patient Name Sample Disease/Disorder Test Results Mr. Jones Mr. Thompson Mr. Niguchi Mrs. Martinez Ms. Smith