Chemical Flashcards
1
Q
What are the three parts of urine testing?
A
Physical, Chemical, Microscopic Analysis
2
Q
What are the medically significant analytes in a urine reagent strip?
A
pH, Protein, Glucose, Ketones, Blood, Bilirubin, Urobilinogen, Nitrite, Leukocytes, Specific Gravity
3
Q
How soon should a urine sample be tested using reagent strips?
A
Within 1 hour of collection
4
Q
How should reagent strips be stored?
A
Opaque container with desiccant, below 30°C, away from volatile fumes
5
Q
What is the primary function of the urine pH test?
A
Measures the degree of acidity or alkalinity
6
Q
What is the normal pH range of first-morning urine?
A
Slightly acidic (pH 5.0-6.0)
7
Q
What dietary factor can cause acidic urine?
A
High protein diet
8
Q
What dietary factor can cause alkaline urine?
A
Vegetarian diet
9
Q
Which urine pH value is considered indicative of an unpreserved specimen?
A
pH 9
10
Q
What chemical system is used in reagent strips for pH testing?
A
Double indicator system (Methyl Red & Bromthymol Blue)
11
Q
Which protein is most commonly detected in urine?
A
Albumin
12
Q
What is the normal amount of protein in urine?
A
<10 mg/dL or 100 mg/24 hrs
13
Q
What protein is produced by renal tubules and found in urine?
A
Tamm-Horsfall protein
14
Q
What is the threshold for clinical proteinuria?
A
> 30 mg/dL (300 mg/L)
15
Q
What is prerenal proteinuria?
A
Proteinuria due to plasma abnormalities, not kidney disease
16
Q
Which disease is associated with Bence Jones protein in urine?
A
Multiple Myeloma
17
Q
What is microalbuminuria an early sign of?
A
Diabetic nephropathy
18
Q
Which reaction is used to detect protein in urine?
A
Protein error of indicators (Tetrabromphenol blue)
19
Q
What is the most frequently tested chemical in urine?
A
Glucose
20
Q
Which condition is primarily detected using urine glucose testing?
A
Diabetes Mellitus
21
Q
Which type of urine specimen is best for diabetes screening?
A
Fasting urine specimen
22
Q
What enzyme-based reaction is used for glucose detection?
A
Glucose oxidase reaction
23
Q
What are the three ketone bodies?
A
Acetone, Acetoacetic Acid, Beta-hydroxybutyric Acid
24
Q
Which ketone body is present in the highest percentage in urine?
A
Beta-hydroxybutyric acid (78%)
25
What condition is most associated with ketonuria?
Type 1 Diabetes Mellitus (insulin deficiency)
26
What chemical is used in reagent strips for ketone detection?
Sodium nitroprusside (Nitroferricyanide reaction)
27
What is the difference between hematuria and hemoglobinuria?
Hematuria = intact RBCs in urine, Hemoglobinuria = free hemoglobin in urine
28
Which conditions cause hemoglobinuria?
Hemolytic anemia, transfusion reactions, severe burns, infections
29
Which protein is present in urine during muscle destruction?
Myoglobin
30
Which reaction is used to detect blood in urine?
Peroxidase activity of hemoglobin
31
What is bilirubin a byproduct of?
Hemoglobin breakdown
32
Why should urine samples be protected from light when testing for bilirubin?
Light exposure leads to false negatives
33
What conditions cause increased urine bilirubin?
Liver disease (Hepatitis, Cirrhosis), Biliary obstruction (Gallstones, Cancer)
34
Which reaction is used to detect bilirubin?
Diazo reaction
35
What is urobilinogen derived from?
Bilirubin metabolism by intestinal bacteria
36
What is the clinical significance of increased urobilinogen in urine?
Liver disease & Hemolytic disorders
37
Which reaction is used for urobilinogen detection?
Ehrlich’s Aldehyde & Diazo reaction
38
What is the purpose of the nitrite test in urine?
Detects urinary tract infections (UTI)
39
Which bacterial process does the nitrite test rely on?
Bacterial reduction of nitrate to nitrite
40
Which reaction is used for nitrite detection?
Greiss reaction
41
What does the leukocyte esterase test detect?
Presence of white blood cells (WBCs) in urine
42
What does a positive leukocyte esterase test indicate?
Urinary tract infection (UTI)
43
What is the normal range for WBCs in urine?
0-2 to 5 per high power field (hpf)
44
Which reaction is used to detect leukocyte esterase?
Esterase hydrolysis reaction
45
What does specific gravity measure in urine?
Kidney’s ability to concentrate urine
46
What is the normal specific gravity range of urine?
1.002 to 1.035
47
Which conditions cause low specific gravity?
Diabetes insipidus, renal tubular damage
48
Which reaction is used to measure specific gravity in reagent strips?
pKa change (polyelectrolyte reaction)
49
Which chemical interferes with multiple urine tests, including glucose and blood?
Ascorbic Acid (Vitamin C)
50
What is a major source of error in urine reagent strip testing?
Failure to read color changes at the correct time
51
What are the three parts of urine testing?
Physical, Chemical, Microscopic Analysis
52
What are the medically significant analytes in a urine reagent strip?
pH, Protein, Glucose, Ketones, Blood, Bilirubin, Urobilinogen, Nitrite, Leukocytes, Specific Gravity
53
How soon should a urine sample be tested using reagent strips?
Within 1 hour of collection
54
How should reagent strips be stored?
Opaque container with desiccant, below 30°C, away from volatile fumes
55
What is the primary function of the urine pH test?
Measures the degree of acidity or alkalinity
56
What is the normal pH range of first-morning urine?
Slightly acidic (pH 5.0-6.0)
57
What dietary factor can cause acidic urine?
High protein diet
58
What dietary factor can cause alkaline urine?
Vegetarian diet
59
Which urine pH value is considered indicative of an unpreserved specimen?
pH 9
60
What chemical system is used in reagent strips for pH testing?
Double indicator system (Methyl Red & Bromthymol Blue)
61
Which protein is most commonly detected in urine?
Albumin
62
What is the normal amount of protein in urine?
<10 mg/dL or 100 mg/24 hrs
63
What protein is produced by renal tubules and found in urine?
Tamm-Horsfall protein
64
What is the threshold for clinical proteinuria?
>30 mg/dL (300 mg/L)
65
What is prerenal proteinuria?
Proteinuria due to plasma abnormalities, not kidney disease
66
Which disease is associated with Bence Jones protein in urine?
Multiple Myeloma
67
What is microalbuminuria an early sign of?
Diabetic nephropathy
68
Which reaction is used to detect protein in urine?
Protein error of indicators (Tetrabromphenol blue)
69
What is the most frequently tested chemical in urine?
Glucose
70
Which condition is primarily detected using urine glucose testing?
Diabetes Mellitus
71
Which type of urine specimen is best for diabetes screening?
Fasting urine specimen
72
What enzyme-based reaction is used for glucose detection?
Glucose oxidase reaction
73
What are the three ketone bodies?
Acetone, Acetoacetic Acid, Beta-hydroxybutyric Acid
74
Which ketone body is present in the highest percentage in urine?
Beta-hydroxybutyric acid (78%)
75
What condition is most associated with ketonuria?
Type 1 Diabetes Mellitus (insulin deficiency)
76
What chemical is used in reagent strips for ketone detection?
Sodium nitroprusside (Nitroferricyanide reaction)
77
What is the difference between hematuria and hemoglobinuria?
Hematuria = intact RBCs in urine, Hemoglobinuria = free hemoglobin in urine
78
Which conditions cause hemoglobinuria?
Hemolytic anemia, transfusion reactions, severe burns, infections
79
Which protein is present in urine during muscle destruction?
Myoglobin
80
Which reaction is used to detect blood in urine?
Peroxidase activity of hemoglobin
81
What is bilirubin a byproduct of?
Hemoglobin breakdown
82
Why should urine samples be protected from light when testing for bilirubin?
Light exposure leads to false negatives
83
What conditions cause increased urine bilirubin?
Liver disease (Hepatitis, Cirrhosis), Biliary obstruction (Gallstones, Cancer)
84
Which reaction is used to detect bilirubin?
Diazo reaction
85
What is urobilinogen derived from?
Bilirubin metabolism by intestinal bacteria
86
What is the clinical significance of increased urobilinogen in urine?
Liver disease & Hemolytic disorders
87
Which reaction is used for urobilinogen detection?
Ehrlich’s Aldehyde & Diazo reaction
88
What is the purpose of the nitrite test in urine?
Detects urinary tract infections (UTI)
89
Which bacterial process does the nitrite test rely on?
Bacterial reduction of nitrate to nitrite
90
Which reaction is used for nitrite detection?
Greiss reaction
91
What does the leukocyte esterase test detect?
Presence of white blood cells (WBCs) in urine
92
What does a positive leukocyte esterase test indicate?
Urinary tract infection (UTI)
93
What is the normal range for WBCs in urine?
0-2 to 5 per high power field (hpf)
94
Which reaction is used to detect leukocyte esterase?
Esterase hydrolysis reaction
95
What does specific gravity measure in urine?
Kidney’s ability to concentrate urine
96
What is the normal specific gravity range of urine?
1.002 to 1.035
97
Which conditions cause low specific gravity?
Diabetes insipidus, renal tubular damage
98
Which reaction is used to measure specific gravity in reagent strips?
pKa change (polyelectrolyte reaction)
99
Which chemical interferes with multiple urine tests, including glucose and blood?
Ascorbic Acid (Vitamin C)
100
What is a major source of error in urine reagent strip testing?
Failure to read color changes at the correct time
101
What is the reaction time for Leukocytes (LEU)?
120 seconds
102
What color indicates a negative result for Leukocytes (LEU)?
Off-white or pale beige
103
What is the reaction time for Nitrites (NIT)?
60 seconds
104
What color indicates a negative result for Nitrites (NIT)?
Off-white or cream
105
What is the reaction time for Urobilinogen (URO)?
60 seconds
106
What color indicates a negative result for Urobilinogen (URO)?
Light peach
107
What is the reaction time for Protein (PRO)?
60 seconds
108
What color indicates a negative result for Protein (PRO)?
Yellow-green
109
What is the reaction time for pH?
60 seconds
110
What color indicates a pH of 5.0?
Orange
111
What color indicates a pH of 6.0?
Light orange
112
What color indicates a pH of 6.5?
Yellow-orange
113
What color indicates a pH of 7.0?
Yellow-green
114
What color indicates a pH of 7.5?
Green
115
What color indicates a pH of 8.0?
Blue-green
116
What color indicates a pH of 9.0?
Dark blue-green
117
What is the reaction time for Blood (BLO)?
60 seconds
118
What color indicates a negative result for Blood (BLO)?
Yellow
119
What is the reaction time for Specific Gravity (SG)?
45 seconds
120
What color indicates a negative result (1.000) for Specific Gravity (SG)?
Dark green
121
What color represents SG of 1.005?
Olive green
122
What color represents SG of 1.010?
Light green
123
What color represents SG of 1.015?
Greenish-yellow
124
What color represents SG of 1.020?
Yellow-green
125
What color represents SG of 1.025?
Yellow-brown
126
What color represents SG of 1.030?
Dark yellow-brown
127
What is the reaction time for Ketones (KET)?
40 seconds
128
What color indicates a negative result for Ketones (KET)?
Peach
129
What is the reaction time for Bilirubin (BIL)?
30 seconds
130
What color indicates a negative result for Bilirubin (BIL)?
Light yellow
131
What is the reaction time for Glucose (GLU)?
30 seconds
132
What color indicates a negative result for Glucose (GLU)?
Blue-green
133
What color does Leukocytes (LEU) turn if highly positive?
Dark pink or purple
134
What color does Nitrites (NIT) turn if positive?
Pink
135
What color does Urobilinogen (URO) turn if highly positive?
Dark pink-red
136
What color does Protein (PRO) turn if highly positive?
Dark green
137
What color does Blood (BLO) turn if highly positive?
Dark yellow-green
138
What color does Ketones (KET) turn if highly positive?
Dark maroon-purple
139
What color does Bilirubin (BIL) turn if highly positive?
Dark brown
140
What color does Glucose (GLU) turn if highly positive?
Dark brown-orange
141
What does a pH of 7.0 indicate in terms of acidity?
Neutral urine
142
What does a pH lower than 7.0 indicate?
Acidic urine
143
What does a pH higher than 7.0 indicate?
Alkaline urine
144
Why should urine be tested at the correct reaction time?
To ensure accurate colorimetric results
145
Which test takes the longest reaction time?
Leukocytes (120 seconds)
146
Which test has the shortest reaction time?
Bilirubin and Glucose (30 seconds each)
147
What does a highly positive blood (BLO) reaction suggest?
Hematuria or hemoglobinuria
148
What condition can a positive nitrite (NIT) test indicate?
Bacterial UTI (especially gram-negative bacteria)
149
What does the presence of bilirubin (BIL) suggest?
Liver disease or bile duct obstruction
150
What does the presence of ketones (KET) suggest?
Diabetic ketoacidosis, starvation, or excessive fat metabolism
