Urine chemical properties

What is it important to remember about drugs and reagent strips

That medications, diets, environmental factors can affect the results

pH

Expresses the hydrogen ion (H+) concentration. Measures degree of acidity or alkalinity of urine.

What organ plays a role in acid-base regulation

The kidneys

What kind of diet increases alkaline urine

Plant diets

What kind of diet increases acidity of urine

High protein cereal diets or meat.

Does normal urine have protein?

None of in very trace amounts, usually because of trauma of collection.

Tests to measure protein

Reagent strips, sulfosalicylic acid turbidity test, urine protein/creatinine ratio.

How should excessive protein levels be confirmed

Sulfosalicylic acid turbidity test, specific biochemical analysis

Sulfosalicylic acid turbidity test

Determines protein levels by acid precipitation.

what can causes increases in glucosuria (especially in cats)

Fear, excitement, restraint.

what can cause a decreased pH

Fever, starvation, excessive muscular activity, or certain drugs

Increased pH causes

UTI with urease bacteria, certain drugs, urine retention

What determines crystal formation

pH

Protein/creatinine ratio

Confirms significant amounts of protein

Proteinuria/cause

Protein in the urine, acute and chronic renal diseases.

What can lead to false negative protein results

Very dilute urine

How much protein in a dilute sample is clinically significant?

Just a trace amount in a dilute sample is clinically significant.

Glucosuria/glycosuria

Presence of glucose in the urine.

Levels of glucosuria depend on

Blood glucose levels, rate of glomerular filtration, tubular resorption

Renal threshold glucose!!!

180mg/dl !!!

High glucosuria can be indicative of?

Diabetes mellitus

Drugs that may cause a false positive glucosuria

Vitamin C, Morphne, Aspirin, Cephalosporins, Penicillin.

What can cause ketonemia

Diabetes mellitus, impaired liver function, high fat diets, starvation, fasting, anorexia.

What causes ketonuria

Ketones are formed during incomplete catabolism of fatty acids. Ketonemia

Who is bilirubin not usually found in (urine)

Cats, sheep, pigs, horses.

Who is bilirubin normal in

Dogs

Why is it abnormal to see bilirubin in cats but not dogs?

Because the renal threshold for bilirubin is much higher in cats than dogs.

Bilirubinuria tests

Ictotest, reagent strips.

Ictotest

A diazo compound in reagent tablets. Blue or purple color. Speed and degree of color change indicates concentration

How can you get a false negative bilirubinuria

If exposed to shortwave lights

Is urobilinogen considered normal in a sample?

Yes

What does a acidic solution have more of

Free H* ions

Hematuria

Presence of intact RBCs in urine.

Hemoglobinuria

Presence of free hemoglobin in urine

Myoglobinuria

Presence of myoglobin in urine

What 3 blood components can occur in the urine simultaneously?

Hematuria, hemoglobinuria, myoglobinuria.

What should you always examine urine sediment for regarding blood

RBCs

Hematuria can be from

Disease causing bleeding somewhere in urogenital tract. Large amounts can be seen in the color, small amounts need to be detected with chemical analysis

Hemoglobinuria can be result of

Result of intravascular hemolysis. Indicative of positive hemoglobin test without RBCs on sediment.

What can be indicative of hemoglobinuria just from looking at it after centrifuging?

A red color to the supernatant after centrifuging.

Causes of hemoglobinuria

immune mediated hemolytic anemic, is immune hemolytic disease of neonates, leptospirosis, heavy metals, poisonous plants.

How can hemoglobinuria occur in cows

After drinking large amounts of water after water deprivation

If urine is dilute or alkaline that means hemoglobinuria could originate from?

Lysis of RBCs in the urine sample

What can you see on a sediment exam that indicates hemoglobinuria

Ghost cells.

Myoglobinuria

Myoglobin is a protein found in muscle and when that protein is found in the urine.

Myoglobinuria causes

Severe muscle damage causes myoglobin to leak into the blood, then go into glomeruli and into urine.

What does the urine look like with Myoglobinuria

Very dark brown to almost black. May look reddish

How to distinguish between hemoglobinuria, Myoglobinuria, and hematuria.

Evaluate the color of the supernatant after centrifuging, hematuria will be clear, while the others cause color. We can also look at symptoms and see what lined up. But it is very difficult.

Myoglobin is seen in frequently in what with who

In horses with external rhabdomyolysis

Leukocytes in urine

reagent test strips used. False-negatives are possible. You need to examine microscopically.