Ch. 3 - Introduction to Urinalysis

Question 1

Give the two unique characteristics of a urine specimen

Answer 1

Readily available and easily collected specimen
Contains information, which can be obtained by inexpensive laboratory tests, about many of the body’s major metabolic functions.

Question 2

Clinical and Laboratory Standards Institute defines urinalysis as

Answer 2

“The testing of urine with procedures commonly performed in an expeditious, reliable, accurate, safe and cost-effective manner.”

Question 3

Enumerate the reasons for performing a urinalysis identified by the CLSI

Answer 3

Aiding in the diagnosis of disease
Screening asymptomatic populations for undetected disorders
Monitoring the progress of disease and the effectiveness of therapy

Question 4

The kidneys continuously form urine as an _____ of plasma.

Answer 4

Ultrafiltrate

Question 5

What is the average daily urine output?

Answer 5

1,200 mL - 1,500 mL

Question 6

Urine is ___% water and ___% solutes.

Answer 6

95; 5

Question 7

Enumerate factors that influence the concentration of solutes in urine

Answer 7

Body metabolism
Endocrine functions
Body position

Question 8

An organic component in urine that is a metabolic waste product produced in the liver from the breakdown of protein and amino acids; this accounts for nearly half of the total dissolved solids in urine

Answer 8

Urea

Question 9

Aside from urea, what other organic substances can be found in urine?

Answer 9

Creatinine

Uric acid

Question 10

This is the major inorganic solid dissolved in urine.

Answer 10

Chloride, followed by sodium and potassium

Question 11

Enumerate formed elements that can be found in urine. These are not part of the original plasma filtrate and increased amounts are often indicative of disease.

Answer 11

Cells
Casts
Crystals
Mucus
Bacteria

Question 12

When determining whether a fluid is urine, the specimen can be tested for its _____ and _____ content. These substances are present in much higher concentrations in urine than in other body fluids.

Answer 12

Urea

Creatinine

Question 13

Urine volume depends on the amount of _____ that the kidneys excrete.

Answer 13

Water

Question 14

Enumerate factors that influence urine volume

Answer 14

Fluid intake
Fluid loss from non renal sources
Variations in the secretion of ADH
Need to excrete increased amounts of dissolved solids, such as glucose or salts

Question 15

Although the normal daily output is usually 1200 to 1500 mL, a range of ___ to ___ mL is considered normal.

Answer 15

600 to 2000

Question 16

The condition wherein there is decreased urine output

Answer 16

Oliguria

Question 17

What is the level of urine for infants suffering from oliguria?

Answer 17

1 mL/kg/hr

Question 18

What is the level of urine for children suffering from oliguria?

Answer 18

0.5 mL/kg/hr

Question 19

What is the level of urine for adults suffering from oliguria?

Answer 19

400 mL/day

Question 20

Oliguria is commonly seen when the body enters a state of dehydration as a result of excessive water loss from what conditions or instances?

Answer 20

Vomiting
Diarrhea
Perspiration
Severe burns

Question 21

The condition where there is a cessation of urine flow; this may result from any serious damage to the kidneys or from a decrease in the flow of blood to the kidneys.

Answer 21

Anuria

Question 22

The kidneys excrete two to three times (more/less) urine during the day than during the night.

Answer 22

More

Question 23

The term used to describe increased nocturnal excretion of urine.

Answer 23

Nocturia

Question 24

The term used to describe increase in daily urine volume.

Answer 24

Polyuria

Question 25

What is the level of urine for children suffering from polyuria?

Answer 25

2.5 - 3 mL/kg/hr

Question 26

What is the level of urine for adults suffering from polyuria?

Answer 26

2.5 L/day

Question 27

Polyuria is usually associated with what types of diabetes?

Answer 27

Diabetes mellitus | Diabetes insipidus

Question 28

Enumerate factors that can artificially induce polyuria

Answer 28

Diuretics Caffeine Alcohol - suppress the secretion of ADH

Question 29

A type of diabetes producing polyuria that is caused by a defect either in the pancreatic production of insulin or in the function of insulin, which results in an increased body glucose concentration. Increased amounts of water must be excreted to remove the dissolved glucose from the body

Answer 29

Diabetes mellitus

Question 30

Although appearing to be dilute, a urine specimen from a patient with diabetes mellitus has a (high/low) specific gravity because of the increased glucose content.

Answer 30

High

Question 31

A type of diabetes producing polyuria that results from a decrease in the production or function of ADH; thus, the water necessary for adequate body hydration is not reabsorbed from the plasma filtrate.

Answer 31

Diabetes insipidus

Question 32

A urine specimen from a patient with diabetes insipidus, the urine is truly dilute and has a (high/low) specific gravity.

Answer 32

Low

Question 33

Fluid loss from diabetes mellitus and diabetes insipidus is compensated by increased ingestion of water called _____, producing an even greater urine volume.

Answer 33

Polydipsia

Question 34

Enumerate analytes that are decreased when a urine sample is allowed to remain unpreserved at room temperature for longer than 2 hrs.

Answer 34

``` Clarity Glucose Ketones Bilirubin Urobilinogen Red and white blood cells and casts ```

Question 35

Enumerate analytes that are increased when a urine sample is allowed to remain unpreserved at room temperature for longer than 2 hrs.

Answer 35

Odor pH Nitrite Bacteria

Question 36

What happens to the color of urine when it is allowed to remain unpreserved at room temperature for longer than 2 hrs?

Answer 36

Modified/darkened due to oxidation or reduction of metabolites

Question 37

What is the most routinely used method of preserving a urine sample?

Answer 37

Refrigeration at 2 - 8 C

Question 38

Refrigeration can (increase/decrease) specific gravity when measured by a urinometer.

Answer 38

Increase

Question 39

Refrigeration can (increase/decrease) the precipitation of amorphous phosphates and urates, which may obscure the macroscopic sediment analysis.

Answer 39

Increase

Question 40

What must be done to counter the increase in specific gravity and precipitation of amorphous phosphates and urates due to the refrigeration of a urine sample?

Answer 40

The specimen must be allowed to return to room temperature before chemical testing

Question 41

What are the characteristics of the ideal preservative to be used when transporting a urine specimen over a long distance and refrigeration is inaccessible?

Answer 41

``` The preservative must be: Bactericidal Inhibits urease Preserve formed elements in the sediment The preservative should not interfere with chemical tests (does not exist) ```

Question 42

This is the most commonly received specimen because of its ease of collection and convenience for the patient. It may be collected at any time

Answer 42

Random specimen

Question 43

The ideal screening specimen; it is essential for preventing false-negative pregnancy tests and for evaluating orthostatic proteinuria.

Answer 43

First Morning specimen or 8-hour specimen

Question 44

It is a concentrated specimen, thereby assuring detection of chemicals and formed elements that may not be present in a dilute random specimen.

Answer 44

First Morning specimen or 8-hour specimen

Question 45

This specimen must be collected immediately upon arising and must be delivered to the laboratory within 2 hours.

Answer 45

First Morning specimen or 8-hour specimen

Question 46

This is the second voided specimen after a period of fasting. This will not contain any metabolites from food ingested before the beginning of the fasting period. It is recommended for glucose monitoring.

Answer 46

Fasting Specimen (Second Morning)

Question 47

The patient is instructed to void shortly before consuming a routine meal and to collect a specimen 2 hours after eating.

Answer 47

2-hour Postprandial Specimen

Question 48

This specimen is tested for glucose, and the results are used primarily for monitoring insulin therapy in persons with diabetes mellitus.

Answer 48

2-hour Postprandial Specimen

Question 49

This type of specimen is sometimes collected to correspond with the blood samples drawn during a glucose tolerance test (GTT). Collection of this specimen is an institutional option.

Answer 49

Glucose tolerance specimen

Question 50

This type of urine sample is tested for glucose and ketones, and the results are reported along with the blood tests results as an aid to interpreting the patients ability to metabolize a measured amount of glucose and are correlated with the renal threshold for glucose.

Answer 50

Glucose tolerance specimen

Question 51

It is a type of urine specimen required when the concentration of the substance to be measured changes with diurnal variations and with daily activities such as exercise, meals, and body metabolism.

Answer 51

24-Hour (Timed) Specimen

Question 52

Give solutes that exhibit diurnal variations (Low concentration in the morning; high concentration in the afternoon)

Answer 52

Catecholamines 17-hydroxysteroids Electrolytes

Question 53

This specimen is collected under sterile conditions by passing a hollow tube (catheter) through the urethra into the bladder.

Answer 53

Catheterized specimen

Question 54

What is the most commonly requested test on a catheterized specimen?

Answer 54

Bacterial culture

Question 55

An alternative specimen for catheterized specimens, provides a safer, less traumatic method for obtaining urine for bacterial culture and routine urinalysis.

Answer 55

Midstream clean-catch specimen

Question 56

It provides a specimen that is less contaminated by epithelial cells and bacteria and, therefore, is more representative of the actual urine than the routinely voided specimen. Patients must be provided with appropriate cleansing materials, a sterile container, and instructions for cleansing and voiding

Answer 56

Midstream clean-catch specimen

Question 57

This is a type of urine sample that is collected by external introduction of a needle through the abdomen into the bladder, which is sterile under normal conditions and, therefore, provides a sample for bacterial culture that is completely free of extraneous contamination. This can also be used for cytologic examination.

Answer 57

Suprapubic aspiration

Question 58

Similar to midstream clean-catch collection, this procedure is used to determine prostatic infection. First and midstream urine are collected in different sterile containers. Then, the prostate will be massaged so that the prostate fluid will be passed with the remaining urine into a third sterile container.

Answer 58

Prostatitis specimen

Question 59

Soft. clear plastic bags with hypoallergenic skin adhesive to attach to the genital area of both boys and girls are available for collecting this type of specimen

Answer 59

Pediatric specimen

Question 60

It is the most vulnerable part of a drug-testing procedure.

Answer 60

Urine specimen collection

Question 61

The process that provides correct collection procedures and documentation of proper sample identification from the time of collection to the receipt of the laboratory results.

Answer 61

Chain of Custody (COC)

Question 62

It is a standardized form that must document and accompany every step of drug testing, from collector to courier to laboratory to medical review officer to employer.

Answer 62

Chain of Custody (COC)

Question 63

For urine drug specimen, the temperature of the urine must be taken within ___ minutes from the time of collection to confirm the specimen has not be adulterated.

Answer 63

4

Question 64

For urine drug specimen, the temperature of the urine must be within the range of ___. Temperature outside this range may indicate specimen contamination.

Answer 64

32.5 C to 37.7 C