Urine Analysis 1429 - Rh - Final

Rommel John Alavazos

Introduction: Urine is a fluid obtained from the blood through the renal glomeruli with considerable changes before it is excreted as urine. The first step in urine formation is by ultrafiltration at the glomeruli which is about 170 – 200 L/24 hrs. During the passage of the ultrafiltrate through the renal tubules, reabsorption of solutes and water in various regions reduces the total urine volume to less than 1% of the ultrafiltrate. There is also active secretion at the renal tubules. Collection of urine specimen depends on the test required either random sample or 24- hours sample. Urine specimen tends to deteriorate unless the correct preservative is added (toluene, chloroform, thymol and formalin) or the specimen is refrigerated throughout the collection period. Urine samples are usually examined for the main items: Physical examination. Biochemical examination. Serological examination. Microscopic examination.

Physical examination: 1. Volume: Normal urine volume: 0.4 -2.0 L/day.  Increased volume (Polyuria) > 2.0 L/day: - Physiological: Excessive water and fluid intake. - Pathological:a. Diabetes mellitus. b. Diabetes insipidus. c. Chronic renal failure.

 Decreased volume (Oliguria) < 0.4 L/day: a. Dehydration. b. Acute renal failure.

2. Appearance:

a. Normal fresh urine is clear. b. Cloudy (turbid) urine is due to abnormal constituents (pus cells, bacteria, salt or epithelial cells).

3. Color: a. Normal color: is pale yellow or amber yellow (due to urochrome and urobilin pigments). b. Colorless urine: very diluted urine due to: Physiological causes: excessive fluid intake in normal person. Pathological causes: uncontrolled diabetes mellitus, diabetes insipidus and chronic renal failure. c. Orange urine: is due to: Ingestion of large amount of carotenoids (vitamin A). Concentrated urine (hot weather, high fever, dehydration..etc).

35

d. Yellow - green urine: is due to bilirubin or biliverdin (jaundice). e. Red urine: is due to:  Ingestion of root beets.

 Some drugs (rifampin for treatment of T.B., carmurit…etc).  Blood or hemoglobin.  Porphyrias. f. Dark brown or black urine: is due to:

   

Methemoglobin. Homogentisic acid in alkaptonuria. Melanin (melanoma).

Malignant malaria (black water fever). g. Smoky urine: is due to presence of RBCs in acute glomerulonephritis.

4. Odor: a. Urineferous odor: normal odor of fresh voided urine (due to presence of aromatic acids). b. Fruity odor: is due to acetone (diabetic ketoacidosis). c. Ammoniacal odor: is due to release of ammonia as a result of the bacterial urease enzyme in the contaminated and long standing exposed urine sample. d. Mousy odor: is due to PKU. e. Burnt sugar odor: is due to maple syrup urine disease.

5. Deposits: a. Normally, the urine contains no deposits. b. Deposits are mainly due to:

 

Crystals, salts or cells. Blood clots, necrotic tissues and urinary stones.

6. Osmolality: It is the number of solute particles per unit weight of water (mmol/kg of water). Measurement of urine osmolality is of value in the investigation of:  Polyuria: - with increased osmolality → Diabetes mellitus. - with decreased osmolality → Diabetes insipidus.  Oliguria : - with increased osmolality → Acute renal failure. - with decreased osmolality → Hypovolemia.

7. Reaction (pH): a. Normal range: 4.6 - 7.0 (the average pH is about 6.0). b. Acidic urine: is due to ketosis (diabetes mellitus & starvation), severe diarrhea, metabolic and respiratory acidosis, excessive ingestion of meat and certain fruits (cranberries). c. Alkaline urine: is due to: - Respiratory and metabolic alkalosis.

36

- Urinary tract infection. - Vegetarians. Red Blood Cells Normal Values: 4.6 – 5.4 ul in female 4.7 – 6.1 ul in male Red blood cells carry oxygen from your lungs to the rest of your body. Abnormal red blood cell levels may be a sign of anemia, dehydration (too little fluid in the body), bleeding, or another disorder. White Blood Cells White blood cells are part of your immune system, which fights infections and disease. Abnormal white blood cell levels may be a sign of infection, blood cancer, or an immune system disorder. A CBC measures the overall number of white blood cells in your blood. A differential count looks at the amounts of different types of white blood cells in your blood. Platelets Platelets (PLATE-lets) are blood cells that help your blood clot. They stick together to seal cuts or breaks and stop bleeding. Abnormal platelet levels may be a sign of a bleeding disorder (not enough clotting) or a thrombotic disorder (too much clotting).

Hemoglobin Hemoglobin (HEE-muh-glow-bin) is an iron-rich protein in red blood cells that carries oxygen. Abnormal hemoglobin levels may be a sign of anemia, sickle cell anemia, thalassemia (thal-a-SE-me-ah), or other blood disorders. If you have diabetes, excess glucose in your blood can attach to hemoglobin and raise the level of hemoglobin A1c. Hematocrit Hematocrit (hee-MAT-oh-crit) is a measure of how much space red blood cells take up in your blood. A high hematocrit level might mean you're dehydrated. A low hematocrit level might mean you have anemia. Abnormal hematocrit levels also may be a sign of a blood or bone marrow disorder.

(Kidneys (BUN Kidney tests measure levels of blood urea nitrogen (BUN) and creatinine. Both of these are waste products that the kidneys filter out of the body. Abnormal BUN and creatinine levels may be signs of a kidney disease or disorder.

37