UA Unit #1.2

Colorless

recent fluid consumption, common color with random specimen

Pale Yellow

polyura or diabetes insipidus, diabetes mellitus, random diluted specimen

Dark Yellow

concentrated specimen, dehydration, B complex vitamins, bilirubin, acriflavine, nitrofurantoin

Pink, red, reddish-brown

hgb or RBC color

Oragne

pyridium color

Green

propofol color

Purple

urine bag syndrome color

Blue

diaper syndrome color

Foul smell

bacterial decomposition, UTI

Fruity smell

ketones

maple syrup smell

maple syrup urine disease

Mousy smell

phenylketonuria

Rancid smell

tyrosinemia

sweaty feet smell

isovaleric acdiemia

cabbage smell

methionine malabsorption

bleach smell

contamination

Foam

presence often indicates high protein concentration

Specific Gravity of Water

1.000

Specific Gravity of plasma

1.010

Specific Gravity of normal urine

1.003 - 1.035

Increased specific gravity

represents interference during specific gravity test

Decreased specific gravity

represents a specimen that may not truly be urine during specific gravity test

Refractometry Specific Gravity

measures total solute, larger particles have more effect. Requires correction for positive glucose and protein

Dipstick Specific Gravity

measures the ionic solute

Dipsticks

plastic strip with reagent pads, protect from light, heat, and moisture

Siemens Multistix and Roche Chemstrip

produce all reactions in the same amount of time on dipstick

Dipstick QC

perform every 24 hours, every new container, and every new lot of QC

Specific Gravity

polyelectrolyte releases H+ in proportion to dissolved ions and bromthymol blue changes color

Specific Gravity False Increase

high protein (anions steal H+)

Specific Gravity False Decrease

pH greater or equal to 6.5

Hyposthenuria

specific gravity lower than plasma. kidney disease, and diabetes insipidus, increased fluid consumption, diuretics

Isotheniuria

specific gravity is the same as plasma (1.010). chronic kidney disease acute kidney injury (if consistently the same)

Hypersthenuria

higher specific gravity than plasma. nephrosis, diabetes mellitus, radiographic dye, dehydration

pH reference range

normally 4.5 - 8.0

pH

methyl red (4-6) and bromthymol blue (5-9)

Protein Reference Range

very little to none present. More than 30 is proteinuria

Types of Protein in Urine

albumin, Tamm-Horsfall, Bence-Jones

Protein

tetrabromophenol blue. as protein steals H+, color changes

Protein False Increase

alkaline urine, strip in urine too long, high SG

Protein False Decrease

non-albumin protein, dilute urine

Prerenal Protein

overflow. multiple myeloma, hemoglobinuria, myoglobinuria, septiciemia

Renal Protein

dehydration/exercise, hypertension, preeclampsia, glomerular disorder, tubular disorder

Postrenal Protein

inflammation/infection of lower urinary tract, prostatic/seminal fluid, blood from injury or menstrual contamination

SSA (Sulfosalicylic Acid Precipitation)

confirmatory test for protein. All types of protein percipitates

Glucose Reference Range

normal urine is negative. glycosuria is positive

Pre-Renal Glucose

serum glucose meets renal threshold of 160-180. Diabetes mellitus

Renal Glucose

poor tubular reabsorption of glucose

Glucose

glucose oxidase reacts with glucose and air, peroxidase reacts with peroxide and chromogen

Glucose False Increase

Peroxide, bleach, improper dipstick storage

Glucose False Decrease

ascorbic acid, bacteria, and cold specimen

Clinitest

early test to dectect reducing sugars in urine, specifically galactose. Used with newborns

Benedict Copper Reduction Reaction

reduces copper sulfate to cuprous oxide in presence of alkali and heat making color change in clinitest

Ketones

intermediate products of fat metabolism. Ketonuria is positive ketones (BHOB)

Ketone Reaction

sodium nitroprusside and acetoacetate

Ketone False Increase

highly pigmented urine, some medications

Ketone False Decrease

delayed testing, ascorbic acid

Acetest

confirmatory test for acetoacetic acid and acetone, replaced by BHOB testing

Diabetic Ketoacidosis

high glucose and ketones

Hyperglycemia without ketosis

High glucose and neg ketones

Ketosis

High ketones and neg glucose

Hematuria

RBC in urine. damage to kidney or genitourinary tract

Hemoglobinuria

free hgb in urine. RBC intravascular hemolysis

Myoglobinuria

myoglobin in urine. heme-containing protein in muscle released by rhabdomyolysis

Blood Reaction

psuedoperoxidase activity of hemoglobin to produce color change with chromogen

Blood False Increase

bleach, menstrual contamination

Blood False Decrease

high SG, ascorbic acid, and unmixed specimen

Bilirubinuria

liver damage/disease or bile obstruction

Bilirubin Reaction

diazo reaction with diazonium salt and acidic medium

Bilirubin False Increase

highly pigmented urine, pyridine (orange)

Bilirubin False Decrease

light exposure, ascorbic acid, and high nitrite

Ictotest

confirmatory test for bilirubin. more sensitive than dipstick

Urobilinogen

intestinal bacteria breakdown billirubin, increased dye to intravascular hemolysis and liver disease/gallbladder obstruction

Urobilinogen Reaction

Ehrlich Reagent and acid buffer

Urobilinogen False Increase

highly pigmented urine

Urobilinogen False Decrease

old specimen, formalin, high nitrite

Nitrite

gram negative bacteria reduce nitrate to nitrite. normal urine is neg

Nitrite Reaction

greiss rxn. nitrite and armomatic amine mix with diazo salt and terahydrobenzoquinolin

Nitrite False Increase

highly pigmented urine

Nitrite False Decrease

non-nitrate reducing bacteria, no dietary nitrates, ascorbic acid, antibiotics, too early

Leukocyte esterase

infection or inflammation in upper or lower tract. found in granules of myeloid cells

Leukocyte Reaction

leukocyte esterase and diazo reaction

Leukocyte False Increase

bleach, formalin, and pigmented urine

Leukocyte False Decrease

ascorbic acid, high glucose, SG, and protein