Urinalysis Chapter 6

Store reagent strips in a dark, sealed container with a drying agent (desiccant) to prevent moisture absorption and degradation.

Keep reagent strips below 30° Celsius (86° Fahrenheit) to prevent chemical reactions from speeding up and causing inaccurate results. Avoid freezing as it can damage the strips.

Don't expose reagent strips to strong vapors or fumes as they can react with the chemicals on the strips and cause inaccurate results.

Use reagent strips before the expiration date printed on the bottle. After that date, the chemicals can degrade and produce inaccurate results.

Check the chemical pads on the strips for discoloration. If they show any signs of change, discard the strips as they may not provide accurate results.

Always remove a strip immediately before use to minimize exposure to air and moisture, which can affect the chemicals on the strip.

Run controls, both positive and negative, at the beginning of each shift to ensure the strips are working correctly. It's like a test run to confirm their accuracy.

Run additional controls whenever a new bottle of strips is opened, when results seem questionable, or when there are concerns about the integrity of the strips. This helps ensure accuracy and reliability throughout the testing process.

A process that ensures test results are accurate and reliable using known samples with expected outcomes.

Reagent strips are used for initial screening of urine, providing quick results. Confirmatory tests are conducted to confirm results obtained from reagent strips, using different methods and reagents.

Confirmatory tests verify the initial results obtained from reagent strips. They use different methods or reagents to provide more specific and sensitive detection.

The kidneys play a crucial role in maintaining the acid-base balance of the body, along with the lungs. This balance affects the pH level in urine.

A healthy individual's first-morning urine pH typically ranges from 5.0 to 6.0, indicating acid-base balance.

After meals, the body starts processing food, leading to a more alkaline urine, as the body tries to neutralize acidic byproducts of digestion.

Random urine samples can have a pH range of 4.5 to 8.0. This range is wider because it represents how pH can fluctuate throughout the day.

Urine pH should be interpreted in the context of other factors, such as blood acid-base status, kidney function, diet, and specimen age.

A measure of the acidity or alkalinity of urine. A pH range of 5 to 9 is measured using a double-indicator system of methyl red and bromothymol blue.

A condition where urine is acidic, indicating either respiratory or metabolic acidosis/ketosis.

A condition where urine is alkaline, indicating either respiratory or metabolic alkalosis.

Defects in the renal tubules' ability to secrete and reabsorb acids and bases. This can lead to various disorders and is important for diagnosing kidney issues.

Solid masses that form in the kidneys, often made of calcium, uric acid, or other substances. These can be painful and block the flow of urine.

The presence of protein in urine, often an early indicator of renal disease.

The primary serum protein found in urine, normally present in very small amounts. It can be elevated in certain conditions.

A glycoprotein produced by renal tubular cells that forms the matrix of casts in urine, primarily used in diagnosing kidney problems.

Proteinuria is the presence of an abnormally high amount of protein in the urine, often exceeding 30 mg/dL.

Prerenal proteinuria occurs when the issue isn't with the kidneys themselves, but rather with the blood plasma. The body's increased levels of low-molecular-weight proteins exceed the kidneys' capacity to reabsorb them, leading to protein in the urine.

Prerenal proteinuria is usually temporary and not a sign of kidney disease. It happens when there's an excess of certain proteins in the blood that get filtered out in the urine.

These proteins, like hemoglobin, myoglobin, and acute phase reactants, are small enough to pass the kidney filter but get overloaded, spilling over into the urine.

Bence Jones Protein (BJP) is a type of monoclonal immunoglobulin light chain that's found in urine during some blood cancers, like multiple myeloma.

Multiple myeloma is a cancer of the plasma cells, the cells that produce antibodies. These cancerous plasma cells make excess monoclonal antibodies, including BJP, which can be detected in the urine.

Routine urinalysis tests may not detect Bence Jones Protein (BJP) as it requires specialized tests like serum electrophoresis and immunoelectrophoresis.

Multiple myeloma is typically diagnosed through chemical methods, not routine urine testing for BJP, though BJP can be a clue for further investigation.

A method for detecting protein in urine using reagent strips that rely on the principle of protein error of indicators. In this method, protein molecules accept hydrogen ions from the indicator, causing a color change even when pH remains constant.

Specific indicator chemicals used in reagent strips to detect protein in urine. The color change in these indicators is influenced by the presence of protein in the urine.

The pH level of urine when using reagent strips for protein detection. At this specific pH level, the indicator will change color in the presence of protein.

A common source of interference with protein detection using reagent strips. Highly alkaline urine can alter the pH of the sample, leading to false-positive results.

A chemical test for protein in urine that involves the precipitation of protein using sulfosalicylic acid (SSA). This method reacts with all protein forms, even those that do not react with reagent strips.

A confirmatory test for protein in urine that can be used to validate results obtained from other methods like reagent strip testing.

The use of centrifuged specimens in the SSA Test. This step is crucial to eliminate contaminants and ensure accurate results.

A factor that can lead to inaccurate results in protein testing using reagents strips. Prolonged contact of the reagent pad with urine can remove the buffer, causing a false-positive reading.

A dye-binding reaction used in albumin test pads that is more specific for albumin than traditional protein measurements, offering greater accuracy.

This chemical (DIDNTB) is used in albumin test strips to detect even small amounts of albumin in urine.

The measurement of the ratio between albumin and creatinine in urine, used to assess kidney function.

A type of test strip used to measure albumin in urine, more sensitive than traditional protein strips and able to pick up smaller amounts of albumin.

The measure of the amount of creatinine, a waste product, in the urine. It is used to assess kidney function.

A chemical reaction that measures creatinine using copper sulfate and other reagents, resulting in a color change from orange to blue.

The principle behind creatinine testing, where copper sulfate and creatinine react to form a peroxidase, causing a color change.

Interference in a urine test caused by visually bloody urine or abnormally colored urine, affecting the accuracy of the results.