Ch 16 - Urinalysis

Question 1

why a first-voided morning specimen is often preferred for urinalysis

Answer 1

it is the most concentrated and most accurate sample

Question 2

what is urea

Answer 2

breakdown of proteins

Question 3

define micturition

Answer 3

to urinate

normal act of voiding urine

Question 4

define nocturnal enuresis

Answer 4

inability of pt to control urination at night during sleep

bedwetting

Question 5

define retention

Answer 5

the inability to empty the bladder

Question 6

where can you find microorganisms in the urethra?

Answer 6

normally only in the distal urethra and urinary meatus

Question 7

what is urine composed of

Answer 7

95% water
5% inorganic and organic substances creatinine

inorganic wastes - chloride, sodium, potassium, calcium, magnesium, phosphate, sulfate

organic wastes - urea, uric acid, ammonia,

Question 8

how much urine does a normal adult excrete

Answer 8

about 700 - 2000 mL of urine per day

Question 9

define anuria

Answer 9

failure of kidneys to produce urine

Question 10

define diuresis

Answer 10

secretion and passage of large amounts of urine

Question 11

define nocturia

Answer 11

excessive voluntary urination at night

Question 12

define nocturnal enuresis

Answer 12

involuntary bedwetting while asleep

Question 13

define oliguria

Answer 13

decreased output of urine

below 400 mL output in 24 hours

due to decreased fluid intake, dehydration, profuse perspiration, vomiting, diarrhea, kidney disease

Question 14

define polyuria

Answer 14

increased output of urine

exceeds 2000 mL output in 24 hours

due to excessive intake of fluids or caffeine which is a mild diuretic, certain drugs, DM, diabetes insipidus, renal disease

Question 15

purpose of first voided or clean catch sample

Answer 15

first voided for pregnancy - greatest concentration of substances

clean catch for testing bacteria

Question 16

purpose of 24 hour urine specimen

Answer 16

to test for kidney stone formation and control and prevent new stone formation

used to perform a creatinine clearance test to check kidney function

Question 17

importance of obtaining a fresh sample for urinalysis

Answer 17

urine sample must be examined within an hour

bacteria will convert urea to ammonia, making it from acidic to alkaline - creating a false positive result on protein test

bacteria will multiply resulting in a cloudy specimen and increase in nitrite

bacteria will eat the glucose if there was any

red blood cells or white blood cells will break down

casts decompose after several hours

Question 18

describe the physical examination of urine

Answer 18

color: presence of yellow pigment called urochrome, produced by breakdown of hemoglobin
normal is straw-yellow to dark amber
hemoglobin or blood - red
bile pigments - greenish or yellow brown
fat or pus - milky

appearance: normally clear, but cloudy due to bacteria, pus, blood, fat, yeast, sperm, mucous threads, fecal contaminants
odor: urine smell, ammonia smell if old, foul smell from UTI, sweet from DM

specific gravity: measures the weight of the urine compared with the weight of an equal volume of distilled water. indicates amount of dissolved substance in urine

SG ranges from 1.003 - 1.030 but is usually between 1.010 - 1.025

Question 19

list the types of chemical examination of urine

Answer 19

pH: between 4.6 - 8.0 but usually a normal diet results in 6.0; higher pH indicates a bacterial infection

glucose

protein

ketone

bilirubin

urobilinogen

blood

nitrite

leukocytes

Question 20

describe the microscopic examination of urine

Answer 20

red blood cells

white blood cells

epithelial cells

casts

misc. structures

Question 21

how to store bottle of reagent strips

Answer 21

59-86F
not refrigerator or freezer

discoloration = bad

Question 22

define casts

Answer 22

cylindric structures formed in the lumen of the tubules that make the nephron

materials in tubules harden, are flushed out, appear in urine in forms of casts

their presence indicates a disease

hyaline casts

granular casts

fatty casts

waxy casts

cellular casts

rbc casts

wbc casts

epithelial casts

bacterial casts

Question 23

crystals in urine

Answer 23

type and number depends on pH of urine. abnormal crystals include leucine, tyrosine, cystine, cholesterol. appear commonly in alkaline urine include amorphous phosphate, triple phosphate, calcium phosphate, ammonium urate crystals

Question 24

glucose in urine

Answer 24

glucose: 160 - 180 mg/mL per 100 mL of blood

Question 25

proteins in urine

Answer 25

protein: indicates a pathological condition such as renal disease or bacterial infection, glomerular filtration problems but temporary increase in protein can be due to stress or strenuous exercise

Question 26

ketones in urine

Answer 26

ketone: normal products of fat metabolism, used by muscle tissue as source of energy. Excess will accumulate in tissues and body fluids known as ketosis

Question 27

bilirubin in urine

Answer 27

bilirubin: released from the breakdown of hemoglobin, transported to liver and excreted into bile, leaves as feces. liver conditions such as gallstones, hepatitis, cirrhosis can cause it to leave in urine yellow brown or greenish with yellow foam when shaken

Question 28

urobilinogen in urine

Answer 28

urobilinogen: as bilirubin excreted by liver into the intestinal tract, bacteria in intestines will convert it to urobilinogen. 50% is reabsorbed into the body but most is excreted as feces. conditions such as excessive hemolysis, infectious hepatitis, cirrhosis, CHF, infectious mononucleosis can increase urobilinogen in urine

Question 29

epithelial cells in urine

Answer 29

epithelial cells: squamous epithelial cells - small amounts are normal and renal epithelial cells are from deeper layers so its presence in urine is abnormal

Question 30

white blood cells in urine

Answer 30

white blood cells: granular, nucleus, round. 1.5 bigger than rbc, 0-8 per HPF is normal. if more may indicate inflammation in genitourinary tract

Question 31

red blood cells in urine

Answer 31

red blood cells: appear colorless, round, biconcave disks are highly refractile. 0-5 per high power field is normal. if more than may indicate bleeding in urinary tract. rbc cannot be seen if they are hemolyzed - lysed from swelling

Question 32

mucous threads in urine

Answer 32

normally present in small amounts in urine long wavy threadlike structures with pointy ends

Question 33

bacteria in urine

Answer 33

bacteria should not be in urinary tract presence of more than a few bacteria indicates contamination of specimen during collection or a UTI

Question 34

yeast cells in urine

Answer 34

smooth refractile bodies with oval shape yeast cells in female patient urine indicates a vaginal contamination of candida albicans may also be present in diabetic mellitus patients

Question 35

parasites in patients

Answer 35

a contaminant from feces or vaginal material trichomonas vaginalis is a parasite that causes inflammation in vagina

Question 36

spermatozoa in urine

Answer 36

is normal after intercourse

Question 37

purpose of rapid urine cultures

Answer 37

quick and efficient, can be done in medical office assist in UTI diagnosis and effectiveness of antibiotic therapy for UTI

Question 38

function of urine pregnancy tests

Answer 38

early diagnosis of pregnancy checks for presence of a hormone called human chorionic gonadotropin for positive reaction using urine and immunoassay reagent strips

Question 39

human chorionic gonadotropin

Answer 39

HCG is produced by the developing fertilized egg and small amounts are secreted in urine and blood highest level in plasma when tested during first trimester

Question 40

serum pregnancy test

Answer 40

radioimmunoassay for HCG in serum of blood can detect earlier and greater accuracy than urine diagnose ectopic pregnancy and other abnormalities of embryonic development and gestational diabetes