1Currently provide a simple, rapid means for performing medically significant
chemical analysis of urine
Reagent strips
2types of multistix
Siemens Healthcare Diagnostics, Deerfield, IN
3types of chemstrip
Roche Diagnostics, Indianapolis, IN
4ERRORS CAUSED BY IMPROPER TECHNIQUE
1. Unmixed Specimens
2. Extended period
3. Run-over
4. Timing
5. Light source
6. Don’t touch the color chart
7. Color Charts
8. Refrigerated spx.
5are defined as test using different reagents or methodologies to detect the
same substances as detected by the reagent strips with the same or
greater sensitivity or specificity
Confirmatory tests
6Normal pH of Urine
4.5 – 8.0
7pH - First morning
5.0 – 6.0
8pH - Prolonged standing
Alkaline
10Causes of Acid Urine
-Emphysema
-Diabetes mellitus
-Starvation
-Dehydration
-Diarrhea
-Presence of acid-producing bacteria (Escherichia coli)
-High protein diet
-Cranberry juice
-Medications (Methanamine mandelate [Mandelamine], Fosfomycin tromethamine [Monurol])
11Causes of Alkaline Urine
-Hyperventilation
-Vomiting
-Renal tubular acidosis
-Presence of urease-producing bacteria
-Vegetarian diet
-Old specimens
12detects the amount of hydrogen ions in the urine to produce a color
change.
Double Indicator System
13REAGENT COLOR
-produces a color change from
red to yellow in the pH range 4
to 6.
Methyl red
14REAGENT COLOR
-turns from yellow to blue in the
range of 6 to 9.
Bromothymol blue
15the most indicative of renal disease is the
protein determination
16often associated with early renal disease, making the urinary protein test
an important part of any physical examination.
Proteinuria
17Normal urine contains very little protein
less than 10 mg/dL or 100 mg per 24 hours is excreted.
18o produced by the renal tubular epithelial cells
o routinely produced in the distal convoluted tubule
Tamm-Horsfall protein (uromodulin)
19- Also called as “overflow proteinuria”
- Protein doesn’t come from the kidney.
Prerenal Proteinuria
20Caused by low-molecular-weight plasma, such as:
• Hemoglobin
• Myoglobin
• Acute phase reactant
21proteinuria due to increased serum protein levels
➔ elevated levels of monoclonal immunoglobulin light chains
Bence Jones Protein
22Proteinuria associated with true renal disease
• Glomerular damage
• Tubular damage
Renal Proteinuria
23small amount of albumin is indicative if renal failure;
There is no albumin in urine
Microalbuminuria
24- prolonged standing will result in increase in protein
Orthostatic Proteinuria
25Causes of tubular dysfunction include exposure to
toxic substances and heavy metals, severe viral
infections, and Fanconi syndrome.
Tubular Proteins
26Fanconi Syndrome
can’t absorb electrolytes
27pagkalabas sa kidney dun nagkaproblem sa protein
Postrenal Proteinuria
28structures of the lower urinary tract
• Ureters
• Bladder
• Urethra
• Prostate
• Vagina
293',3",5',5"-tetrachlorophenol
Multistix
303,4,5,6-tetrabromosulfonphthalein
Chemstrip
31PROTEIN REAGENT STRIP
-False-negative
• Proteins other than albumin
• Microalbuminuria
32PROTEIN REAGENT STRIP
-False-positive
• Highly buffered interference alkaline urine
• Pigmented specimens
• Phenazopyridine
• Quaternary ammonium compounds (detergents)
• Antiseptics
• Chlorhexidine
• Loss of buffer from prolonged exposure of
the strip to the specimen reagent
• High specific gravity
33cold precipitation test
• must be performed on centrifuged
specimens to remove any extraneous
contamination.
Sulfosalicylic Acid Precipitation Test
34Testing for Microalbuminuria
• Micral-test
(contain a gold-labeled antihuman
albumin antibody-enzyme conjugate)
• Immuno-dip
(Uses an immunochromographic technique.)
35the blood level of glucose be come elevated
Hyperglycemia
36The glucose oxidase procedure provides a specific test for glucose.
Double sequential enzyme reaction
37GLUCOSE REAGENT STRIP
-Multistix
(green to brown)
• Glucose oxidase
• Peroxidase
• Potassium iodide
38GLUCOSE REAGENT STRIP
-Chemstrip
(yellow to green)
• Glucose oxidase
• Peroxidase
• Tetramethylbenzidine
39GLUCOSE REAGENT STRIP SENSITIVITY
-Multistix
75 to 125 mg/dL
40GLUCOSE REAGENT STRIP SENSITIVITY
-Chemstrip
: 40 mg/dL
41GLUCOSE REAGENT STRIP
-False-positive
• Contamination by oxidizing agents and
detergents
42GLUCOSE REAGENT STRIP
-False-negative
High levels of ascorbic acid
• High levels of ketones
• High specific gravity
• Low temperatures
43- also known as “Clinitest”
- The test relies on the ability of glucose and other substances to reduce
copper sulfate to cuprous oxide in the presence of alkali and heat.
Copper Reduction Test
44- Developed in 1908
- Contains:
• Copper sulfate
• Sodium carbonate
• Sodium citrate buffer
Benedict Solution
45- More convenient method that employs the Benedict’s principle
- Contains:
• copper sulfate
• sodium carbonate
• sodium citrate
• sodium hydroxide
Clinitest Tablet
46 represents three intermediate products of fat metabolism
• acetone (2%)
• acetoacetic acid (20%)
• B-hydroxybutyrate (78%)
Ketones
47Reasons for Increased fat metabolism includes:
1) Inability to metabolize carbohydrate → diabetes mellitus
2) Increased loss of carbohydrate → Vomiting
3) inadequate intake of carbohydrate → starvation
48shows a deficiency in insulin, indicating the need to regulate dosage.
• It is often an early indicator of in sufficient insulin dosage in type 1
diabetes and in patients with diabetes who experience medical
problems in addition to diabetes.
Ketonuria
49acetoacetic acid in an alkaline medium reacts with sodium nitroprusside
to produce a purple color.
Sodium nitroprusside Glycine (Chemstrip)
50KETONES REAGENT STRIP Sensitivity
-Multistix
5 to 10 mg/dL acetoacetic acid
51KETONES REAGENT STRIP Sensitivity
-Chemstrip
9 mg/dL acetoacetic acid; 70 mg/dL
acetone
52KETONES REAGENT STRIP
-False-positive
• Phthalein dyes
• Highly pigmented red urine
• Levodopa
• Medications containingfree sulfhydryl groups
53KETONES REAGENT STRIP
-False-negative
• Improperly preserved specimens
54 Provides:
• Sodium nitroprusside
• Glycine
• Disodium phosphate
• Lactose (gives better color differentiation)
In tablet form
Acetest Tablets
55- urine in the form of intact red blood cells
-produces a cloudy red urine
Hematuria
56- urine as the product of red blood cell destruction, hemoglobin
-appears as a clear red specimen
Hemoglobinuria
57most closely related to disorders of renal or
genitourinary origin in which bleeding is the result of
trauma or damage to the organs of these systems.
Hematuria
58result from the lysis of red blood cells produced in the
urinary tract, particularly in dilute, alkaline urine.
Hemoglobinuria
59- no red blood cells are seen
intravascular hemolysis
60heme-containing protein found in muscle tissue
• clear red-brown urine
Myoglobinuria
61conditions associated with muscle destruction
Rhabdomyolysis
62catalyze a reaction between the heme component of both hemoglobin
and myoglobin and the chromogen tetramethylbenzidine to produce an
oxidized chromogen
Pseudoperoxidase Activity of Hemoglobin
63Pseudoperoxidase Activity of Hemoglobin cp;pr
• Green-Blue color
64BLOOD REAGENT STRIP Reagents
-Multistix
Diisopropylbenzene
dihydroperoxide and 3,3’,5,5’ tetramethylbenzidine
65BLOOD REAGENT STRIP Reagents
-Chemstrip
• dimethyldihydroperoxyhexane
• tetramethylbenzidine
66BLOOD REAGENT STRIP Sensitivity
-Multistix
Multistix:
5 to 20 RBCs/mL, 0.015 to
0.062 mg/dL hemoglobin
67BLOOD REAGENT STRIP Sensitivity
-Chemstrip
5 RBCs/mL, hemoglobin corresponding
to 10 RBCs/mL
68BLOOD REAGENT STRIP
-False-positive
• Strong oxidizing agents
• Bacterial peroxidases
• Menstrual contamination
69BLOOD REAGENT STRIP
-False-negative
• High specific gravity/crenated cells
• Formalin
• Captopril
• High concentrations of nitrite
• Ascorbic acid greater than 25 mg/dL
• Unmixed specimens
70 can provide an early indication of liver disease.
• often detected long before the patient exhibits jaundice
Bilirubin
71a highly pigmented yellow compound, is a degradation product of
hemoglobin
- cells of the reticuloendothelial system convert the remaining protoporphyrin to bilirubin.
Bilirubin Production
72BILIRUBIN REAGENT STRIP Principle
Diazo Reaction
73BILIRUBIN REAGENT STRIP
-Multistix
2,4-dichloroaniline diazonium salt
74BILIRUBIN REAGENT STRIP REAGENTS & SENSITIVITY
-Chemstrip
2,6-dichlorobenzene diazonium salt
75The higher the concentration of urine, the more hydrogen ions are
released, thereby lowering the pH.
• blue → 1.000 (alkaline)
• yellow → 1.030 (acid)
pKa
76when conjugated bilirubin is excreted through the bile duct into the
intestine, the intestinal bacteria convert the bilirubin to a combination of
urobilinogen and stercobilinogen.
Urobilinogen
77cannot be reabsorbed and remains in the intestine where it is oxidized to
stercobilin
Stercobilinogen
78provides a rapid screening test for the
presence of urinary tract infection (UTI).
Nitrite Test
79UROBILINOGEN REAGENT STRIP
Principle
Greiss Reaction
80UROBILINOGEN REAGENT STRIP REAGENT
-Multistix
p-arsanilic acid Tetrahydro benzo(h)-quinolin-3-ol
81UROBILINOGEN REAGENT STRIP REAGENT
-Chemstrip
Sulfanilamide, hydroxy tetrahydro
benzoquinone
82UROBILINOGEN REAGENT STRIP SENSITIVITY
-Multistix
0.06 to 0.1 mg/dL nitrite ion
83UROBILINOGEN REAGENT STRIP SENSITIVITY
-Chemstrip
0.05 mg/dL nitrite ion
84detection of increased urinary leukocytes required microscopic examination
of the urine sediment.
Leukocyte Esterase Test
85Normal values for leukocytes are based on the microscopic sediment
examination and vary from
0 to 2 to 0 to 5 per high power field.
86catalyze the hydrolysis of an acid ester embedded on the reagent pad
to produce an aromatic compound and acid.
LE Reaction
87LEUKOCYTE ESTERASE REAGENT
-Multistix
• Derivatized pyrrole amino acid ester
• Diazonium salt
88LEUKOCYTE ESTERASE REAGENT
-Chemstrip
Indoxyl carbonic acid ester
Diazonium salt
89LEUKOCYTE ESTERASE SENSITIVITY
Multistix:
5 to 15 WBC/hpf
Chemstrip:
10 to 25 WBC/hpf
90LEUKOCYTE ESTERASE
False-positive
• Strong oxidizing agents
• Formalin
• Highly pigmented urine, nitrofurantoin
91LEUKOCYTE ESTERASE
False-negative
High concentrations of protein, glucose, oxalic acid, ascorbic acid,
gentamicin, cephalosporins, tetracyclines; inaccurate timing
92SPECIFIC GRAVITY REAGENTS
Multistix:
Poly (methyl vinyl ether/maleic
anhydride) bromothymol blue
Chemstrip:
Ethylene glycol diamino ethyl ether
tetra acetic acid, bromothymol blue
93SPECIFIC GRAVITY SENSITIVITY
1.000 to 1.030
94SPECIFIC GRAVITY
False-positive
• High concentrations of
protein
95SPECIFIC GRAVITY
False-negative
• Highly alkaline urines
(greater than 6.5)