urine part 3.docx

Objectives - Discuss the chemical properties assessed in routine urinalysis - Correct methods for using a reagent strip - Potential sources of error - Interpretations - Potential causes for abnormal results  Chemical Properties 1. pH 2. Protein 3. Blood...

Objectives - Discuss the chemical properties assessed in routine urinalysis - Correct methods for using a reagent strip - Potential sources of error - Interpretations - Potential causes for abnormal results  Chemical Properties 1. pH 2. Protein 3. Blood 4. Glucose 5. Bilirubin 6. Ketones 7. Leukocyte bd20016\_ pH - Approximation - Normal values (5.5-7.5 pH) - Used as a crude index for acid-base balance - Urine needs to be fresh to get accurate results - May help in determination of uroliths - Alkaline urine (\>7) - phosphate and magnesium ammonium phosphate (struvite) - Acid urine (\ - May help in analyzing a neg test for leptospirosis organisms; the organism may not survive in acid urine causing a false negative  Alkaline Urine - Diet - vegetable - Administration of alkalinizing agents - Metabolic Alkalosis - Respiratory alkalosis - Urinary tract infection by urease producing organisms - Postprandial - Urine retention - Urine allowed to stand open at room temperature  Acidic urine - Diet - meat - Administration of acidifying agents - Metabolic acidosis - Respiratory acidosis - Fever - Starvation - Excessive muscular activity Therapeutic Management  pH is often manipulated to aid in dissolving or preventing certain uroliths - phosphate and Magnesium ammonium phosphate crystals dissolve more readily in acid urine - Cystine and uric acid crystals are more soluble in alkaline urine Urinary acidifiers cat5 Protein - Proteinuria - Much more sensitive to albumin than globulins - Must be read at proper time interval - Qualitative analysis is determined by reading the color change of the reaction pad - Trace, 1+ - 4+ - Semi-quantitative amount corresponds to the qualitative change 10mg/dl-1000mg/dl  Proteinuria - False positives results can occur in alkaline urine or urine contaminated with disinfectants (quaternary ammonium) - False negatives can occur in urine that is acidic or very dilute - Occasional small amount of protein is found in the urine in normal animals  Interpretation - Proper interpretation cannot be made by dip strip alone; it must include the animal's: - history - physical examination findings - method of urine collection - urine sediment  Interpretation Urine specific gravity must be taken into consideration when evaluating proteinuria - 1+ (30mg/dl) with SG 1.007) - 1+ with SG of 1.045 Proteinuria with an inactive urine sediment or urine sediment with large numbers of casts - usually of renal origin  Clinical Indications of True Proteinuria Acute and chronic renal disease Diseases of the urinary tract Congestive heart failure Traumatic catheterizations Drugs or chemicals  Blood - Reagent strip detects the presence of intact RBCs (hematuria), hemoglobin (hemoglobinuria), and myoglobin (myoglobinuria) - All may occur at the same time - The reagent strip is slightly less sensitive to intact cells than hemoglobin  Possible 3 indications - Hematuria - Moderate to large amount of blood give the urine a cloudy red, brown or wine color - Occult blood  - Urine is not obviously discolored by blood but is detected by chemical analysis - Hemoglobinuria - color is similar but with a transparency that remains after centrifugation - Myglobinuria - brownish red-amber appearance - clear transparency - Due to break down of muscle - Muscle injury - Malignant hyperthermia (High Fever)  - False positives can occur - Bleach - Iodide or bromide - False negative - Urine sample is not mixed well - Normal results should be negative cat15A screenshot of a medical test Description automatically generated Glucose - Glucosuria - Amount of glucose in urine is dependent: - Blood glucose levels - Rates of glomerular filtration and tubular absorption - Renal threshold: - dog 180 mg/dl, cat 300 mg/dl - Color reaction corresponds to quantity of glucose present in the urine sample Causes of Glucosuria  - High carbohydrate meal - Fear or excitement - Diabetes mellitus - Hyperthyroidism - Cushing\'s - Liver disease False positives  - Vitamin C - Morphine - Aspirin Drugs: Cleaning agents  IV fluids with glucose added A black and white text on a gray background Description automatically generated Bilirubin - Conjugated bilirubin or urobilinogen - Low renal threshold - Canine kidneys have the ability to conjugate bilirubin - Bilirubinuria - Maybe indicative of some disorder that has the potential to produce icterus - Male dogs may have a small amount of bilirubin normally present in their urine - Normal cat urine should show no signs of bilirubin  Bilirubinuria  Prolonged fever Hemolysis Obstructed bile duct Pancreatitis Liver disease Cats: - FIP, Hepatic diseases, FeLV SO01349\_ - False negatives can occur when the urine is exposed to light - dip stick reaction of 2+-3+ for bilirubin is considered abnormal in dogs with moderately concentrated urine (1.020- 1.035) - Ictotest  Ketones  Formed during the catabolism of fatty acids Ketonuria  Uncommon in dogs or cats Relatively common in diary cattle and sometimes swine  Ketonuria - Diabetes Mellitus (ketoacidosis) Impaired ability to utilize available carbohydrates - Starvation - Strenuous exercise - Exposure to cold Inadequate carbohydrates consumption - Renal - Intestinal disorders Loss of carbohydrates  Ketones False positives may occur with highly pigmented urine Urinary ketones are measured by color intensity that is roughly proportional to concentration of urine ketones  Leukocytes  Intact or lysed leukocytes Specific for canines that have pyuria Positive is indicative of pyuria, but a negative is not conclusive Has many false negatives Often leads to false positives in cats  Technique - Fresh urine - Well mixed - Room temperature - Comparison should be done in good lighting - Read at specific times - Watch expiration date of reagent strips - not touch chemical reagent pad - Strips stored properly Review - Technique for performing a dip stick - Basic components - Terminology - Normal values - Clinical indications for positive results for individual tests - What may cause false positives on individual tests