The urinary system - Assignment Example

The change of color in the urine strip that occurs in the segment of the strip is then compared to a color chart in order to come up with conclusive outcome (Tortora & Derrickson 2010). To complete a conclusive urinalysis, it is imperative to have a clean catch sample which is collected after cleansing the urethral midstream. Such samples collected via these methods are extremely important in urine culture analysis. As a first examination method urinalysis is undertaken macroscopically in order to ascertain the visual properties of the urine sample.

Usually, cotton gauze soaked in benzalkonium hydrochloride is used for collection purpose because it is a non-irritant. In normal conditions, fresh urine is pale to dark yellow or amber in color. Additionally, the urine sample is clear and normally the urine volume is between 750 to 2000mililitres per 24 hour (Mundt & Shanahan 2010). Urine analysis via dipstick is a chemical procedure that examines the potential gradient on the levels of acid and alkaline conditions. The renal tubules and collecting ducts of the kidney usually have an acidic impact on the glomerular filtrate.

This potential gradient is usually between 6.0 and 7.4 in the final urine. Exceptionally, this potential difference in the level of acidity or alkalinity may vary depending on the status of the homeostatic environment. Dipstick method measures the specific gradient. Imperative to note is that specific gradient is directly proportional to osmolality which examines the concentration of solute. This measurement is carried out using a refractometer in a majority of clinical laboratories (Tortora & Derrickson 2010).

Dipstick urine analysis also measures protein presence in urine samples. This can be achieved through whole urine sample or via semi-quantitative tests for the presence of urine proteins. This is normally performed after the centrifugation of supernatant of the urine sample. Dipsticks are able to identify proteins by production of color using an indicator mostly bromophenol blue, a most sensitive indicator to albumins. Additionally, precipitation of the urine sample by heat can be used in the detection of proteins.

Normal total protein concentration in urine usually does not exceed 150 milligrams in 24 hours or 10ml/100ml of the urine sample. In cases where the concentration is higher than 150ml/24h, the condition is called protenuria and in severe cases it is referred to as nephritic syndrome. Dipsticks are also capable of examining the glucose concentration in urine. This is achievable because the technique employs the glucose oxidase reaction that is capable of screening glucose group of sugars including other reducing sugars.

Conditions where glucose occur in quantities greater than 130mg/24hou indicating diabetes mellitus is generally termed as glycosuria (Funnell & Lawrence 2008). Dipsticks are also effective in the detection of ketones including beta-hydroxybutyric acid, acetone and acetoacetic acid. Such ketones arise from diabetic conditions or in cases of starvation. Dipsticks through the nitrite test can be positive to indicate the presence of bacteria usually in large quantity. Gram negative bacteria such as a E.

coli usually indicate a positive nitrite test in urine samples. The presence of white blood cells in urine is called pyuria and can be detected by the leukocyte esterase test. This condition results from