C7: Chemical Examination of Urine

to preliminarily screen for the following chemcials. limited in assessing the exact cause of abnormal readings, so requires additional confirmatory tests

• specific gravity measures the concentration of urine.
• Having a high concentration would indicate that the patient is dehydrated or has a loss of body fluids
• normal range is 1.010 - 1.025

• any abnormal changes in pH level of urine may induce crystal formation and disrupt the stability of formed elements in urine
• normal range is 4.5 - 8.0

• presence of blood in urine may be due to trauma within the tubules.
• Sometimes lysis of RBCs occur due to fluctuations in urine pH which would affect microscopic examinations of urine

positive results indicate UTI when in the presence of bacteria or nonbacterial yeast or inflammation of acute interstitial nephritis (confirmed with positive for nitrite)

• positive for UTI (urinary tract infection)
• nitrite is the product of gram negative bacteria
• conditions include (UTI, cystitis, bladder dysfunction, urine stasis

• testing for three types of protein
• Tamms-horsfal protein - found in shells of casts
• urokinase - fibrinolytic enzyme
• immunoglobin A - synthesized by renal tubular cells
• normal values = 150 mg

because myoglobin is easily filtered by the glomerular filtration, the plasma appears normal in color (pale yellow) compared to hemoglobinuria (pink to red) due to hemolysis

myoglobinuria is the presence of myoglobin, an iron carrying oxygen protein found in the muscles. It is excreted in the blood stream during strenuous exercises (traumatic) or acute renal failure, due to alcohol overdose or heroin cocaine addiction (nontraumatic)

1.5mg/dL

ascorbic acid - which may lyse RBCs

hemorrhoidal blood contamininants

ascorbic acid, specimen storage, bladder retention time

microscopic examination

excessive amount of proteins in the body