ACTIVITY 9 URINALYSIS

1. ACTIVITY 9URINALYSIS Medical Physiology Lab.

2. Urinalysis • A urinalysis is a group of manual and/or automated qualitative and semi-quantitative tests performed on a urine sample. • It is a test that checks many body functions in one exam. • Once you know what to look for, you can see what’s going on with various systems.

3. Purpose Routine urinalyses are performed for several reasons: 1. general health screening to detect renal and metabolic diseases. 2. diagnosis of diseases or disorders of the kidneys or urinary tract. 3. monitoring of patients with diabetes.

4. Functions of kidney: • The human kidneys have four major functions. They are to: 1.Remove metabolic waste and toxins from the body. 2. Regulate the volume and composition of the body fluids through secretion and reabsorption. 3. Maintain the balance of acids to bases in the body (i.e., pH). 4. Produce metabolites such as renin and vitamin D that are important to other body tissues and cells.

6. Physical Characteristics of Urine: 1. Color Normal = pale yellow due to a pigment called urochrome. Color is associated with solute concentration. Increased solutes = darker urine; Decreased solutes = colorless urine, like water. Solute concentration is measured using a urinometer to determine specific gravity. Specific gravity of water = 1.000 Specific gravity of normal urine = 1.001 to 1.030

7. Color

8. 2. Transparency • Normal = clear • Abnormal = cloudy, which may be caused by bacteria, blood, cells, crystals, etc.

9. 3. Odor • Normal = slightly aromatic when freshly voided. • Bacteria = ammonia odor • Asparagus, drugs and diseases my also impart a characteristic odor. • Diabetes mellitus = urine smells "fruity" or like acetone.

10. 4. pH • Normal pH = 4.5 to 8.0 (average is about 6.0) • High protein diet = acid urine • Vegetarian diet = alkaline urine

11. 5. Specific gravity Normal = 1.001 to 1.030. Low Specific Gravity may be due to: • Excess fluid intake • Use of diuretics • Diabetes insipidus • Chronic renal failure High Specific Gravity may be due to: • Low fluid intake • Fever • Pyelonephritis

12. Excessively concentrated urine may lead to kidney stones (renal calculi), that are made of crystals of salts that are present in urine such as uric acid, calcium oxalate or calcium phosphate. • Decreased water intake and increased calcium intake may also cause kidney stones.

13. Normal Constituents of Urine • Water • Urea • Sodium and potassium • Phosphate and sulfate ions • Creatinine • Uric acid • Calcium • Magnesium • Bicarbonate ions

14. Abnormal Constituents of Urine • Glycosuria = glucose • Hematuria = Red blood cells • Pyuria = White blood cells • Bacteriuria = bacteria • Ketonuria = ketones

15. Terminology of Urine Output • Polyuria = excessive production of urine • Anuria = decreased production of urine • Dysuria = painful urination

16. Urinary Disorders: • Diabetes mellitus = decreased production or utilization of insulin. (Ketonuria with glycosuria is usually diagnostic for diabetes mellitus). • Diabetes insipidus = large amounts of dilute urine is excreted, usually 5-20 liters per day. • Caused by inadequate secretion of antidiuretic hormone (ADH). • UTI = bacterial infection of the urinary tract.

17. Urethritis = inflammation of the urethra • Cystitis = inflammation of the urinary bladder • Pyelonephritis = inflammation of the kidneys • Glomerularnephritis = inflammation of glomeruli in kidneys • Acetonuria = ketone bodies in the urine • Azotemia = presence of urea in the blood • Enuresis = bed wetting

18. Nephrotic syndrome = protein in the urine due to increased permeability of the glomerular capillary endothelium • Cystocele = hernia of the urinary bladder • Polycystic kidney disease = most common inherited disorder of the kidneys • Nephrotosis = floating kidney • Micturition = urination

19. Urine Dipstick: • Each of the squares corresponds to something being tested. • You are supposed to compare the colors of each square to a suggested color on the box to determine if things are normal.

23. 1. Glucose • Renal threshold for glucose is such that after a certain point is reached, the glucose spills over. The specific threshold level depends on the patient. Even within an individual, the personal threshold varies daily. • Therefore the dipstick test for glucose is really inaccurate.

24. 2. Ketones Produced from fatty acids. • Causes of ketones in the urine are starvation and diabetes mellitus, ketoacidosis, etc. • Two major ketones in the body • Beta hydroxybutyric acid • Acetoacetate • The dipstick test is non-specific and only sensitive to the second type of ketone (acetoacetate). • If you do a dipstick test, and it comes back ketone +, perform a serum ketone level because something is definitely going wrong.

25. 3. Blood in the urine: Two situations • HEMOGLOBINURIA = blood in the urine but the red blood cell (RBC) are NOT intact. The cause is hemolysis. • HEMATURIA = intact red blood cells in the urine. This points to the urinary tract as the source of the problem. • Kidney • Ureter • Bladder

26. 4. Protein: • a. Proteins are NOT supposed to be in the urine • b. Prevention of proteins into the urine is done by glomerular membrane. 5. Bilirubin: • NOT supposed to be in the urine

27. 6. Urobilinogen: Grade this from 1 – 5 (5 being the highest) a. with high RBC destruction 7. Nitrates: Made by many bacteria species (with the exception of Staph & Strep) a. e.g. E. coli, Proteus, Pseudomonas etc. b. If nitrate +, urinary tract infection is suggested (UTI) c. a – test does NOT rule out a UTI

28. 8. Leukocyte esterase: enzyme • White blood cell (WBC) in urine noted by implication • The enzyme esterase is normal in urine • + for this enzyme then probably a UTI

29. 9. Casts: Lots of different material clumped together inside of the renal tubule. • As a general rule if a cast is present, then something is going on. • Exception to the above rule is if you see a hyaline cast, which is a normal finding. • Clumped cells come from the kidney • Casts can be RBC or WBC casts • If you see these in the urine, tells you that there is a disease from the bladder  kidney (moving up).

30. Casts • If you see RBC – kidney problem • Could be: • Pyelonephritis • SLE • Kidney stones • Trauma (e.g. hit in the flank/abdomen) • If you see WBC casts – probably due to infection.

31. 10. Crystals: • Very small amount is normal • Could be due to gout or liver disease 11. Bacteria: • urine is considered sterile, therefore bacteria in the urine is not normal • If + for bacteria, probably due to a UTI.

32. Microscopic Analysis of urine sediment • Unorganized sediments – chemical substances that form crystals or precipitate from solution. • Calcium oxalates, carbonates and phosphates; • Uric acid • Ammonium urates • Cholesterol • Crystals are frequently found in the urine. They are formed by the precipitation of urine salts subjected o changes in pH, temperature or concentration, which affect their solubility. Crystals are identified by their appearance, solubility and pH.

37. Organized sediments – Epithelial cells, WBC, RBC, casts. • Cells can be anywhere in the urinary tract from the tubules to the urethra. • Casts are cylindric structures formed primarily within the lumen of the distal convoluted tubule and collecting duct. The major constituent of casts is Tamm-Horsfall protein, a glycoprotein excreted by the renal tubular cells. • Normal – negative