AUBF MIDTERM

Macroscopic Analysis

Analysis of urine and body fluids that involves examining physical characteristics and performing chemical analysis.

Microscopic Analysis

Analysis of urine sediment under a microscope to identify the components of the urinary sediments.

Specimen Evaluation

The process of evaluating the urine specimen for proper labeling, volume, container, storage condition, preservation, and absence of contamination.

Urine Volume

The amount of urine excreted by the kidneys, which is influenced by factors such as fluid intake, fluid loss, antidiuretic hormone secretion, and the need to excrete dissolved solids.

Oliguria

Decrease in urine output, commonly seen in conditions such as vomiting, diarrhea, and perspiration.

Polyuria

Increase in daily urine volume, commonly seen in conditions such as diabetes mellitus, diabetes insipidus, and the use of diuretics.

Anuria

Complete cessation of urine flow, usually indicating serious kidney damage.

Nocturia

Increase in the nocturnal excretion of urine, which may be seen in conditions such as pregnancy.

Urine Color

The color of urine, which can vary from almost colorless to black, and is influenced by normal metabolic functions, physical activity, ingested materials, and pathologic conditions.

Specific Gravity

The measure of the concentration of solutes in urine, which is determined by the degree of hydration and can be assessed using a urinometer or refractometer.

Coloring Pigments of Urine

The pigments that contribute to the color of urine, including urochrome (which causes yellow color), uroerythrin (which produces a pink color in refrigerated urine), and urobilin (which gives an orange-brown color to non-fresh urine).1. Abnormal Urine Color:Unusual color of urine that may indicate the presence of abnormal substances or conditions.

Bilirubin

Abnormal pigment that can cause dark yellow or amber urine and may indicate liver or gallbladder problems.

Urobilinogen

Substance that can cause yellow-orange urine when oxidized, often due to certain medications or urinary tract infections.

Hemoglobinuria

Presence of hemoglobin in the urine, resulting in red or pink urine, often caused by the breakdown of red blood cells.

Myoglobinuria

Presence of myoglobin in the urine, resulting in red or brown urine, often caused by muscle breakdown.

Porphyrins

Substances that can cause red urine, often referred to as "port-wine urine," due to the oxidation of porphobilinogen.

Menstruation

Non-pathogenic cause of red urine in females during their menstrual cycle.

Contamination

Non-pathogenic cause of red urine due to external factors, such as contact with blood or certain foods.

Alkaline Urine

Urine with a high pH level, which can cause red coloration when consuming fresh beets.

Acidic Urine

Urine with a low pH level, which can cause red coloration when consuming blackberries.

Methemoglobin

Abnormal form of hemoglobin that cannot bind oxygen, resulting in brown urine.

Melanin

Pigment produced in excess during the presence of malignant melanoma, causing brown or black urine.

Homogentisic Acid

Metabolite of phenylalanine that can cause black urine in patients with a metabolic disorder called alkaptonuria.

Urinary Indican

Substance produced by bacteria in the intestines that can cause blue or green urine.

Clarity

The transparency or turbidity of a urine specimen.

Amorphous Urates and Carbonates

Precipitates that can cause white cloudiness in urine.

Squamous Epithelial Cells

Non-pathogenic cells that can cause hazy urine, especially in women.

Semen

Non-pathogenic cause of urine turbidity due to the presence of sperm.

Fecal Contamination

Non-pathogenic cause of urine turbidity due to contact with fecal matter.

Radiographic Contrast Media

Non-pathogenic cause of urine turbidity due to the presence of contrast agents used in medical imaging.

Bacterial Growth

Improper preservation of urine that can lead to bacterial growth and increased turbidity.

Amorphous Phosphate and Carbonates

Precipitates that can cause a white precipitate in alkaline urine.

Pathogenic Turbidity

Turbidity in urine caused by the presence of pathogens, indicating a possible infection or disease.1. Pathologic causes of Urine Turbidity:Presence of RBC, WBC, and Bacteria caused by infection or a Systemic Organ Disorder.

Other causes of Urine Turbidity

Abnormal amounts of Non-squamous Epithelial cells, Abnormal Crystals, Lymph fluid, Yeasts, & Lipids.

Clarity of urine

Provides a key to the Microscopic examination results, as the amount of Turbidity should correspond with the amount of material observed under the microscope.

Clear Urine

Not always normal, as most abnormalities in the urine can be detected prior to the Microscopic Analysis with the sensitivity of routine Chemical tests.

Specific Gravity

The density of a solution compared with the density of similar distilled water (SG = 1.000). The specific gravity of urine is based on the kidney's ability to concentrate the Glomerular filtrate by selectively reabsorbing essential chemicals and water.

Refractometry

Measures Refractive index of urine. Advantages include determining Specific Gravity using a small volume of urine and compensating for temperature at 15°C-38°C. Corrections for Glucose and Protein must be calculated by subtracting 0.003/gram of Protein present and 0.0004/gram of Glucose present.

Abnormally High Specific Gravity results

Seen in patients who have recently undergone an IV Pyelogram or are receiving Dextran or other High Molecular Weight IV fluids (Plasma Expanders).

Urinometry

Consists of a weighted float attached to a scale calibrated in terms of urine SG. Calibration temperature is 20°C, with adjustments made for colder or warmer temperatures.

Osmolality

The Osmolarity of a solution can be determined by measuring a property mathematically related to the number of particles in a solution. Unlike Refractometry, it is only influenced by the number of particles.

Harmonic Oscillation Densitometry

Based on the principle that the frequency of a sound wave entering a solution changes in proportion to the density of the solution. This technique was originally used in early automated urinalysis instruments but has been replaced by Reagent Strip Analysis for SG.

Reagent Strip Specific Gravity

Principle is based on the pKa (dissociation constant) of a Polyelectrolyte in an Alkaline Urine. The Polyelectrolyte ionizes, releasing Hydrogen ions in proportion to the number of ions in the solution. The indicator used is Bromothymol Blue, which changes color as the SG increases.

Urine Odor

Freshly voided urine has an aromatic odor, urine that stands for a long time has an ammonia odor, urine with bacteria infection has an ammonia-like odor, urine with diabetes ketones has a sweet/fruity odor, maple syrup disorder has a maple syrup odor, phenylketonuria has a mousy odor, tyrosinemia has a rancid odor, isovaleric acidemia has a sweaty feet-like odor, methionine malabsorption has a cabbage-like odor, and contamination can cause a bleach odor.

Maple syrup urine disease (MSUD)

A rare inherited condition where the body cannot process certain amino acids, causing a harmful build-up of substances in the blood and urine.

Phenylketonuria (PKU)

A genetic condition that causes elevated levels of phenylalanine to build up in the body.

Tyrosinemia

A genetic disorder characterized by problems breaking down the amino acid tyrosine.

Isovaleric acidaemia (IVA)

A rare inherited condition where the body can't process the amino acid leucine, causing a harmful build-up of the substance in the blood and urine.1. Reagent Strip:A strip composed of chemical-impregnated absorbent pads that produce a color reaction when in contact with urine.

Color Chart

A chart supplied by the manufacturer that is used to interpret the color reactions produced on the reagent strip.

Multistix

A type of reagent strip manufactured by Siemens Healthcare Diagnostics.

Chemstrip

A type of reagent strip manufactured by Roche Diagnostics.

Dip

To completely immerse the reagent strip in urine.

Blot

To horizontally press the reagent strip on an absorbent medium pad to remove excess urine.

Timing

The specified length of time to wait for reactions to take place on the reagent strip.

Light Source

A good light source is essential for accurate interpretation of color reactions on the reagent strip.

Interchangeable

Reagent strips and color charts from different manufacturers cannot be used interchangeably.

Room Temperature

Reagent strips should be stored at room temperature and not refrigerated.

Expiration Date

The date stamped on the reagent strip bottle that represents the functional life expectancy of the strips.

Positive and Negative Controls

Reagent strips must be checked with both positive and negative controls to ensure accuracy.

Reflectance Photometry

The principle used in automated reagent strip readers, where light reflection decreases in proportion to the intensity of color produced.

Glucose

The most common sugar in urine, normally not detected in normal urine.

Renal Threshold

The concentration of glucose in the urine that exceeds the normal range.

Thin Layer Chromatography

A method used to identify other sugars in urine.

Hyperglycemia

High levels of glucose in the blood and urine.

False-Positive

A result that indicates the presence of glucose when there is none due to contamination.

False-Negative

A result that indicates the absence of glucose when there is actually a high level of ascorbic acid present.1. High levels of ketones:Elevated levels of ketone bodies in the body due to increased fat metabolism.

High specific gravity

A measure of the concentration of solutes in urine, indicating dehydration or kidney dysfunction.

Low temperatures

Referring to the conditions in which improperly preserved specimens are stored, which can affect the accuracy of test results.

Improperly preserved specimens

Urine samples that have not been stored or handled correctly, leading to potential degradation or contamination.

Copper Reduction Test (Clinitest / Benedict's Test)

A test that measures the ability of glucose and other substances to reduce copper sulfate to cuprous oxide, indicating the presence of glucose in urine.

Pass through phenomenon

A phenomenon where high levels of glucose in urine can cause a color change in the test reaction to pass through multiple stages.

False-Positive

A result that indicates the presence of a substance when it is actually not present.

Glucose Oxidase

An enzyme used in the Clinitest to detect the presence of glucose in urine.

Interpretation

The process of analyzing and understanding the results of a test.

Bilirubin

A pigmented yellow compound formed from the breakdown of hemoglobin, which can indicate liver disease when present in urine.

Conjugated Bilirubin

Water-soluble bilirubin that can be detected in urine and provides an early indication of liver disease.

Amber urine

Urine with a yellow color, often seen in cases of bilirubin presence.

Urine Bilirubin and Urobilinogen in Jaundice

The levels of bilirubin and urobilinogen in urine can help diagnose different causes of jaundice.

Bile duct obstruction

Blockage in the bile ducts, which can lead to increased levels of bilirubin in urine.

Liver Damage

Damage to the liver, which can result in elevated bilirubin levels in urine.

Hemolytic Disease

A condition where there is excessive breakdown of red blood cells, leading to increased bilirubin levels in urine.

Clinical Significance of Bilirubin in Urine

The importance of detecting bilirubin in urine as an indicator of various liver diseases and conditions.

Reagent strip for Bilirubin

A test strip that uses the "Diazo Reaction" to detect the presence of bilirubin in urine.

False-Negative

A result that indicates the absence of bilirubin when it is actually present.

Ictotest (Tablet)

A tablet test that is more sensitive than reagent strips in detecting bilirubin in urine.

KETONES

Substances produced from the breakdown of fatty acids when glucose is not used as an energy source.

KETONE BODIES

The end products of rapid or excessive fatty acid breakdown, including beta-hydroxybutyric acid, acetoacetic acid, and acetone.

Reagent strip for Ketones

A test strip that uses the "Nitroprusside" reaction to detect the presence of ketones in urine.

False-Positive

A result that indicates the presence of ketones when it is actually not present.

False-Negative

A result that indicates the absence of ketones when they are actually present.

Acetest (Tablet)

A tablet test that detects the presence of ketones in urine.1. Specific Gravity:The density of a solution compared to the density of a similar volume of distilled water at the same temperature. It is influenced by the number and size of particles in the solution and is used to monitor patient hydration, dehydration, and renal function.

Reagentstrip

A test strip used to measure specific gravity in urine. It contains a polyelectrolyte that ionizes and releases hydrogen ions in proportion to the number of ions in the urine, causing a color change in relation to the ionic concentration.

Protein

A substance found in urine that is indicative of renal diseases. Proteinuria, the presence of protein in the urine, is associated with renal disorders. Normal urine contains very little protein, with normal values being less than 10 mg/dL or 100 mg/24 hrs. Albumin is the major protein found in urine and its presence can indicate renal dysfunction.

Tamm-Horsfall (Uromodulin)

A mucoprotein found in the matrix of renal tubular casts. It is produced by renal tubular cells and can be present in urine along with protein from prostatic, seminal, and vaginal secretions.

Pre-Renal Proteinuria

Proteinuria caused by conditions that affect the plasma prior to reaching the kidney. This can include intravascular hemolysis, muscle injury, severe infection and inflammation, and multiple myeloma.

Renal Proteinuria

Proteinuria caused by true renal disease. This can be further classified into glomerular proteinuria, which is associated with conditions like diabetic nephropathy, and tubular proteinuria, which occurs when normally filtered albumin cannot be reabsorbed by the tubules.

Post-Renal Proteinuria

Increased protein in the urine caused by inflammation or infections that add protein to the urine after its formation. This can include lower urinary tract infections, injury/trauma, menstrual contamination, prostatic fluid/spermatozoa, and vaginal secretions.

Micral Test

A test for microalbuminuria, which is proteinuria undetectable by routine reagent strips. It employs an antibody-enzyme conjugate that binds to albumin and uses an enzyme immunoassay principle for detection.

Reagent Strip for Protein

A test strip used to measure protein in urine. It is based on the protein error-of-indicator principle, where the development of any green color indicates the presence of protein. It is sensitive to albumin but less sensitive to globulins.1. High specific gravity:The measure of the concentration of solutes in urine.

False-Negative

A result that incorrectly indicates the absence of a particular substance or condition.