Lab.9 - General Urine Examination PDF

Charmo University COLLEGE OF SCIENCE Department of Medical Laboratory Science Practical Physiology- Lab.9 Wednesday, January 08, 2025 Lecturer: Sarwar M. Rashid 1 ...

Charmo University COLLEGE OF SCIENCE Department of Medical Laboratory Science Practical Physiology- Lab.9 Wednesday, January 08, 2025 Lecturer: Sarwar M. Rashid 1  General Urine Examination (G.U.E.)  G.U.E.: is the physical, chemical, and microscopically examination of urine. It involves a number of tests to detect and measure various compounds that pass through the urine, also called urine analysis (Urinalysis).  URINE- is a liquid mainly consisting of water and waste products of our body, generated through filtering the blood by the kidneys, the process is called urination. It is usually yellow in color, depending on the ratio of urea and water in it. The more urea increases, the more yellow it tends to be. If the water increases, it becomes more transparent or light. Wednesday, January 08, 2025 2  Urine Composition  Urine is a very complex fluid, is composed of 95% water and 5% solid, the average urinary out put of 1-2 L per day.  Normal composition of urine  Major Organic Constituents: - Urea, Creatinine, Uric acid, Hippuric acid, Amino acid, Ammonia. - Other Organic Acids: lactic acid, citric acid, oxalic acid, and other metabolites.  Major Inorganic Constituents: - Water, Electrolytes (sodium, potassium, chloride, small amounts of Ca, Mg). - Sulfates and Phosphates. - Traces elements of Zn, Cu, Fe, I. 3 Wednesday, January 08, 2025  Urinalyses are performed for several reasons Diagnosis of metabolic or systemic diseases that affect kidney function. Diagnosis of diseases or disorders of the kidneys or urinary tract. Monitoring of patients with diabetes. Testing for pregnancy. Screening for drug abuse. Frequent urination or Foul-smelling urine. Pain or burning sensation while urinating. Urgent need to urinate. Foamy or cloudy urine. Abdominal pain or Pain during sexual intercourse. Yellowing of the skin and eyes. Wednesday, January 08, 2025 4  Types of Urine Collection Early morning sample- qualitative. Random sample- routine (at any time). 24hrs sample- quantitative. Clear catch sample (midstream urine) - UTI. Postprandial sample- (Diabetes mellitus)  How to collect urine specimen The specimen must be collected in a clean dry, disposable container. The container must be properly labeled with the patient name, date, and time of collection. The specimen must be delivered to the laboratory on time and tested within 1hr, or it should be refrigerated or have an appropriate chemical preservative added. eg. (formalin, boric acid or toluene) Wednesday, January 08, 2025 5  Analyzing Urine Sample  A complete urinalysis usually involves 3 steps: 1. Checking and recording the PHYSICAL CHARACTERISTICS of the urine. 2. Performing a CHEMICAL ANALYSIS using a multi-test dipstick. 3. Centrifuging a small portion of the sample and examining the sediment under a MICROSCOPE. Wednesday, January 08, 2025 6  MACROSCOPIC EXAMINATION 1- COLOR:  Normal: pale yellow  No color (clear): increase fluid intake  Dark yellow: insufficient fluid intake  Foamy: pregnancy & kidney disease  Red: blood in urine  Brown: liver disease  Green: problem with bile metabolism Wednesday, January 08, 2025 7 2- APPEARANCE:  Normal urine- should be clear (transparent).  Abnormal urine- can be hazy, cloudy, or turbid. 3- ODOR:  Normal odor- normally urine have mild smell.  Abnormal odors Ammonia odor: due to bacterial decomposition, or due to infections and diseases of the liver. Fruity odor: due to presence of acetone (diabetes). 4- VOLUME:  Normal- urine volume is (1000 to 2000 ml/day).  Abnormal- Increased (Diuretic therapy, Diabetes insipidus, Diabetes mellitus). Decreased (Excess sweating, Dehydration, Acute renal failure). Wednesday, January 08, 2025 8  Chemical Analysis (Urine test strips) A standard urine test strip may comprise up to 10 different chemical pads or reagents which react (change color) when immersed in, and then removed from, a urine sample. The test can often be read in as little as (1 to 2) min, after dipping. Routine testing of the urine with multipara-meter strips is the first step in the diagnosis of a wide range of diseases. The analysis includes testing for the presence of (glucose, bilirubin, ketones, specific gravity, blood, pH, proteins, urobilinogen, nitrate, Leukocyte esterase). Wednesday, January 08, 2025 9  Chemical Analysis includes  PH: Normal- 6-7.5  Abnormal- o Low PH- Acidic  Diseases: (diabetic, diarrhea, starvation)  Medication: antibiotic (Methenamine) o High PH- Alkaline  Diseases: (stone, UTI, kidney related disease)  Medication: (Acetazolamide) Urinometer 10 Wednesday, January 08, 2025  Specific gravity: is a measure of the concentration of solutes in the urine and provides information on the kidney's ability to concentrate urine. Normal range (1.005 – 1.030). o Sp. Gravity is affected by: volume of urine excreted & amount of solids present in the urine.  Specific gravity methods- Dipsticks, Urinometer, Refractometer.  Ketones: normal urine does not contain ketones.  Abnormal- (ketonuria) when you have (diabetes, low carbohydrate intake, severe vomiting, diarrhea).  Nitrite: which are not found in normal urine. Many Gram-negative and some Gram-positive bacteria are capable of producing nitrite. Wednesday, January 08, 2025 11  Glucose (sugar): normally, urine contains very little or no glucose (0 to 0.8) mmol/L (millimoles per liter). Appearance of glucose is sign of diabetic.  Bilirubin: in the urine may be due to gallstones in the biliary tract, jaundice & some liver diseases.  Urobilinogen: normal urine contains some urobilinogen, 0.1-1.8 mg/dl (1.7-30 µmol/l).  Too much urobilinogen - may be a sign of liver disease: such as (hepatitis or cirrhosis), certain types of anemia.  Little or no urobilinogen- may be a sign of other problems with your liver, gallbladder, bile ducts  Bloody urine: may be due to a problem in your kidneys or other parts of the urinary tract, such as: cancer of the bladder or kidney, infection of the bladder, kidney, prostate, or urethra.  Protein (albumin): total proteins levels of urine are very small. Normal protein excretion does not usually exceed 150 mg/24 hours (or 10 mg/100 ml in any single specimen). 12 Wednesday, January 08, 2025  Proteinuria can be divided into three categories 1. Transient (intermittent) proteinuria- is the most common, this type usually resolves without treatment. Stresses such as fever and heavy exercise may cause transient proteinuria. 2. Orthostatic proteinuria- occurs when one loses protein in the urine while in an upright position but not when lying down. The most common in adolescents, the cause is not known. This type is not harmful, does not require treatment, and typically disappears with age.  To test requires collecting two urine samples: one while you are standing or sitting up (usually during the day) and another after you have been sleeping for several hours. 3. Persistent proteinuria- in contrast to transient and orthostatic proteinuria, persistent proteinuria occurs in people with underlying kidney disease or other medical problems. Examples include: Kidney diseases, Diseases that affect the kidney, such as Diabetes Mellitus or High Blood pressure. Diseases that cause the body to overproduce certain types of protein. Wednesday, January 08, 2025 13  Microscopic Examination  RBCs (hematuria): is the presence of abnormal numbers of red cells in urine due to (glomerular damage, tumors, UT stones, bacterial or parasitic infection), may also contaminate the urine from the vagina in menstruating women. Presence of a few is normal (2-5) cells/HPF.  Results is written in the report (+, ++, +++, ++++).  Two Types of Hematuria  Gross hematuria- the blood can be seen by the naked eye. The urine may look pinkish, brownish, or bright red.  Microscopic hematuria- the urine is clear, but blood cells can be seen under a microscope. Wednesday, January 08, 2025 14  Pus cells (dead WBCs): are a collection of dead WBCs, a few are normal, but high number indicate inflammation or infection somewhere along the urinary or genital tract, or with acute glomerulonephritis is called pyuria. Normal ≤ 2-5 WBCs/HPF.  Results is written in the report (+, ++, +++, ++++). Usually, the WBC's are granulocytes (have lobed nuclei and granular cytoplasm), from the vagina, especially in the presence of vaginal and cervical infections. Wednesday, January 08, 2025 15  Epithelial Cells: are cells that come from surfaces of our body, such as our skin, contain a large round or oval nucleus. In a healthy individual, a small number of epithelial cells can be present in the urine. However, an increased number of epithelial cells in the urine can be a sign of inflammation or infection in the urinary tract. Normal ≤ 15-20 squamous epithelial cells/HPF in female.  Results is written in the report (+, ++, +++, ++++). Wednesday, January 08, 2025 16  Casts: they are solid and cylindrical structures formed by precipitation of debris (WBCs, RBCs, kidney cells) or substances such as protein, in the renal tubules.  Casts are of two main types: 1. Non-cellular casts: ① Hyaline cast- clear, transparent, and homogeneous. The causes nonspecific. ② Granular cast- coarse or finely granular. Exercise, dehydration or acute tubular necrosis (dead tissue). ③ Waxy cast- opaque (dirty), brittle, and have sharp edges. Advanced chronic kidney disease. ④ Fatty casts- contain fat droplets. Various types of tubulointerstitial disorder (inflammation of kidneys tubules). 2. Cellular casts: ① R.B.C. cast- yellow to reddish, containing RBCs. Glomerulonephritis. ② W.B.C. cast- contain WBCs. Pyelonephritis or other tubulointerstitial inflammation. ③ Epithelial cast- composed of renal tubular epithelial cells. Acute tubular injury, glomerulonephritis. Wednesday, January 08, 2025 17 Wednesday, January 08, 2025 18  Crystals: it's normal to have a few small crystals in your urine, but certain types of crystals may stick together and become Calcium oxalate (monohydrate) Calcium oxalate kidney stones. The common crystals are seen (octahydrate) include calcium oxalate, triple phosphate Ammonium magnesium crystals and amorphous phosphates. (triple phosphate)  Mucus: secreted by glands in the lower UT, small number is normal. But become more with UTI, ulcerative colitis, kidney stone, bladder cancer. 1/8/2025 Wednesday, January 08, 2025 19 19  Amorphous: it includes o Amorphous urate (acidic urine). o Amorphous phosphate (alkaline urine). Their formation is caused by a combination of factors, including decreased urine volume combined with changes in urine pH and often the presence of large quantities of uric acid (meat consumption), or calcium (dairy products) in the diet.  Bacteria: are common in urine specimens because of the abundant normal microbial flora of the vagina or external urethral and also their ability to rapidly multiply in urine standing at room temperature. But with pus is abnormal.  Results is written in the report as seen. The common bacteria are seen in urine (Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Enterococcus faecalis and Staphylococcus saprophyticus). Wednesday, January 08, 2025 Bacteria 20  Organisms Wednesday, January 08, 2025 21 Monilia Parasites Bacteria Wednesday, January 08, 2025 22  Microscopic Examination  Procedure o A sample of well-mixed urine (usually 10-15 ml) is centrifuged in a test tube at relatively low speed (about 2-3,000 rpm) for 5-10 minutes, to obtain some sediment, a variety of normal and abnormal cellular elements may be seen in urine, including: RBCs, WBCs, Epithelial cells, Crystals, and Bacteria. o The supernatant is decanted and a volume of 0.2 to 0.5 ml is left inside the tube. o The sediment is re-suspended in the remaining supernatant by flicking the bottom of the tube several times. A drop of re-suspended sediment is poured onto a glass slide and cover slipped. Wednesday, January 08, 2025 23 o The sediment is first examined under low power to identify most crystals, casts, squamous cells, and other large objects. o The numbers of casts seen are usually reported as number of each type found per low power field (LPF).  Example: 5-10 hyaline casts/LPF. o Next, examination is carried out at high power to identify crystals, cells, and bacteria. o The various types of cells are usually described as the number of each type found per average high power field (HPF).  Example: 1-5 WBC/HPF. Wednesday, January 08, 2025 24