Quiz 2 Flashcards
What constitutes the chemical examination?
- pH
- Protein
- Glucose
- Ketones
- Blood
- Bilirubin
- Urobilinogen
- Nitrite
- Leukocyte Esterase
- Specific Gravity
What is the purpose of quality control?
Ensure that the reagent strips are accurate and precise
What is the normal range for pH?
4.5-8.0
What regulates the acid-base balance (pH)?
Kidneys and lungs
Clinical Significance of an acid urine (below 6.0)
High protein diets, medications, diabetes mellitus, starvation, dehydration, diarrhea, certain renal stones
Clinical Significance of an Alkaline urine (above 6.5)
After meals, hyperventilation, vomiting, urease-producing bacteria, vegetarian diet, old specimens, certain renal stones
The pH reagent strip is what kind of system?
Double pH indicator
What chemical indicators are used in the pH reagent strip?
Methyl Red and Bromthymol Blue
What is the normal value for protein?
< 100 mg/ 24 hours
What clinical significance does protein show?
Renal disease
Proteins tested for are:
Albumin
Serum and tubular microglobulins
Tamm-Horsfall protein
Prostatic, seminal, and vaginal protein secretions
Proteinuria
Increase protein in urine ( > 30mg/dL)
What major pathological causes are there to indicate a protein problem?
- Prerenal
- Renal
- Postrenal
Prerenal
condition affecting plasma prior to kidney; infection/inflammation; too much protein to reabsorb
Renal
Glomerular damage and tubular damage
Postrenal
Protein added as passes through lower urinary tract
What are nonpathological causes of proteinuria?
- Exposure to cold
- Strenuous exercise
- High fever
- Orthostatic (postural)
Protein Reagent Strip: Indicator
Tetrabromphenol blue
What could give you a false positive for protein?
*Highly buffered alkaline urines, delay in reading results, high specific gravity
What would give false negatives for a protein?
*Measures mostly albumin and may miss other proteins
What confirmatory tests are used for protein?
Sulfosalicyclic Acid Precipitation
What is the renal threshold for glucose?
160-180 mg/dL
Glycosuria
Increase of urine glucose
Causes of glycosuria?
Diabetes mellitus Pancreatitis Advanced renal disease Hyperthyroidism Emotional stress
What is the chemical basis for the glucose reagent strip?
Double sequential enzymatic reaction based on action of glucose oxidase on glucose
What two enzymes are used in the glucose reagent strip?
Glucose oxidase
Peroxidase
What could cause a false negative for glucose?
Ascorbic acids, ketones, pH, specific gravity, aspirin, low temperatures
What test is done to confirm a positive glucose test?
Clinitest
What principle is the clinitest based off of?
Uses the benedict principle