[2S] UNIT 7 HbA1c & Nyco Card Flashcards
Percentage of HbA
97%
Percentage of HbA2
2.5%
Percentage of HbAF
0.5%
A protein in its quaternary structure - larger unit that is made up of tertiary units - made up of 4 polypeptide chains (2a & 2b)
HbA
T/F: Glycogen is always found in the extracellular fluid
F; Glucose
T/F: Glucose finds a way to the valine terminal molecules
T
Formation of a hgb compound produced when glucose reacts with the amino group of hemoglobin
Glycosylated Hemoglobin
GLYCOSYLATED HEMOGLOBIN
The glucose molecule attaches non enzymatically to the hgb molecule to form a _______
ketoamine
The rate of formation is directly proportional to the plasma glucose concentration
Glycosylated Hemoglobin
Reflects the average blood glucose level over the previous 2 to 3 months
Glycosylated Hemoglobin
Forms the major fraction of adult hemoglobin
HbA1
T/F: Glycosylated Hemoglobin is tested to measure short-term glucose metabolism
F; Long-term
More reliable method of monitoring long-term diabetes control than random plasma glucose
HbA1c
T/F: Current ADA guidelines recommend that an HbA1c test be performed at least 2 times a year with patients who are meeting treatment goals and who have stable glycemic control
T
T/F: For patients whose therapy has changed or who are not meeting glycemic goals, a quarterly HbA1c test is recommended
T
T/F: HbA1c testing does not require fasting and is a long term diabetes control
T
T/F: Glycated hemoglobin is not an antigen
F; it is an antigen
Most to least antigenic molecule
- Proteins
- Polysaccharides
- Lipids / Nucleic Acid
Any type of molecules that invoke an immune response
Antigen
METHODS BASED ON STRUCTURAL DIFFERENCES
Polyclonal or monoclonal antibodies toward the glycated N-terminal group of the b-chain of hemoglobin
Immunoassays
METHODS BASED ON STRUCTURAL DIFFERENCES
Not affected by other hemoglobins
Affinity Chromatography
METHODS BASED ON STRUCTURAL DIFFERENCES
Separates based on chemical structure using borate to bind glycosylated proteins
Affinity Chromatography
Nobel prize winners: antibodies method
Start with B lymphocyte of the mouse and vaccine it with foreign protein to gather antibodies and be utilized as reagent for assays
Milstein & Kohler
METHODS BASED ON STRUCTURAL DIFFERENCES
Not temperature
dependent
Affinity Chromatography
Plasma cell
Nucleus: ______
Chromatin: _______
__________ Halo
- Eccentric
- Cart-wheel
- Perinuclear Halo
- Elongated
Gathered and utilized as reagent of immunoassays and labeled with radioactive dye or enzymes
Antibodies
Principle of Nyco Card
Reflectometry / Reflectance Photometry
BASED ON CHARGE DIFFERENCES
Positive-charge resin bed
Ion-exchange chromatography
BASED ON CHARGE DIFFERENCES
Highly temperature dependent
Affected by hemoglobinopathies
Ion-exchange chromatography
BASED ON CHARGE DIFFERENCES
Separation is based on differences in charge & MW
Electrophoresis
BASED ON CHARGE DIFFERENCES
Type of electrophoresis using isoelectric point to separate
Isoelectric Focusing
BASED ON CHARGE DIFFERENCES
Hemoglobin F values > 7% interfere
Electrophoresis
BASED ON CHARGE DIFFERENCES
pre-HbA1c interferes
Isoelectric Focusing
BASED ON CHARGE DIFFERENCES
A form of ion-exchange chromatography - gold standard for identifying glycated hemoglobin
High-pressure liquid chromatography
BASED ON CHARGE DIFFERENCES
Separates of all forms of glyco-Hb: A1a , A1b , A1c
High-pressure liquid chromatography
Specimen requirement for HbA1c
EDTA Whole Blood Sample
Whole blood may be stored at?
4 °C for up to 1 week
T/F: The ideal specimen for HbA1c is fresh specimen
T
T/F: Whole blood sample is slightly lower in glucose than plasma or serum. Nevertheless, it does not affect the results of HbA1c
T
Measures light reflected from the coloured surface of the NycoCard tests in three parts of the visible spectrum and calculates the test concentration
The NycoCard™ READER II
The NycoCard™ READER II is a _________
reflectometer
Reflected light from the test sample is measured relative to a white sample
The NycoCard™ READER II
T/F: NycoCard™ HbA1c Key Features
10 minutes test time
F; 3 mins
T/F: NycoCard™ HbA1c Key Features
5 µL sample volume (capillary blood)
T
T/F: NycoCard™ HbA1c Key Features
4%–15% HbA1c measuring range / linearity
T
T/F: NycoCard™ HbA1c Key Features
Boronic acid affinity test principle
– No interference from common Hb variant
T
T/F: NycoCard™ HbA1c Key Features
Boronic acid is the working principle not the labelling mechanism
F; BA is the labelling mechanism
T/F: NycoCard™ HbA1c Key Features
Traceable to the IFCC reference method
T
T/F: NycoCard™ HbA1c Key Features
NGSP and IFCC certified
T
T/F: NycoCard™ HbA1c Key Features
Perfect for running (small) test series
T
How does nyco card differentiate non-glycosylated hemoglobin to glycosylated hemoglobin?
Boronic acid affinity test principle
2 reagents in 24 prefilled tubes
Lysing solution & Boronic acid
Washes away non-reacting analytes
1 vial of washing soln
TEST RESULT TIME
Liquid on the membrane
0 minute
T/F: Results in nyco card reader should be read within 5 minutes
T
TEST RESULT TIME
Too dry / crumpled membrane
> 5 minutes
TEST RESULT TIME
Stable hemoglobin precipitate on the membrane (most ideal)
10 seconds - 5 minutes
TEST RESULT TIME
False elevated HbA1c readings
0 minute
- Binds selectively to OH groups
- Selective affinity for cis-diol configuration
Boronic Acid
The affinity of boronic acid to the cis-diol configuration of glycated hemoglobin
NycoCard™ HbA1c Test Principle
2 functional groups are adjacent towards one another across the cyclic ring
cis
NycoCard HbA1c is based on a
boronic acid affinity test
principle
Color of glycoslated hemoglobin stained by boronic acid
Blue
2 OH groups located adjacent to one another
cis-diol
T/F: The LCD display presents the results in percentage
T
The vertical optic system of the nycocard to differentiate HbA1c to hemoglobin that are not glycosylated
Nycocard Reader Pen
Where you place samples
Lid
Measures the color intensity of reflected light
NycoCard Reader
T/F: Red color intensity is directly proportional to Total hemoglobin
T
2 lights needed for NycoCard
2 Light-emitting diode
Light detector
T/F: The ratio between the blue and red reflected light will tell us how much exactly in that made up of glycosylated Hgb
T
T/F: Blue color intensity is directly proportional to Total glycated hemoglobin
T
T/F: For every 1% increase in the HbA1c result, there is always a 35 mg/dL in blood glucose
T
Interpret:
HbA1c = 5.7% - 6.4%
Borderline High
Interpret:
HbA1c = beyond 6.4%
Diabetes Mellitus
Interpret:
HbA1c = 6% - 7%
Retinopathy
The incidence of ________ increases in patients with a HbA1c level between 6.0 to 7.0%
retinopathy
T/F: Fewer chances for retinopathy when the HbA1c level is <6.5%
T
T/F: HbA1c level in diabetic patients recommended <7.0%
T
T/F: This is suggested that HbA1c level above 6.5% favor diabetes mellitus
T
T/F: HbA1c should be checked at least once a year
F; twice
T/F: In interpreting HbA1c, if it prolongs the life span of RBC, it increases HbA1c
T
Old RBCs = ↑ contact between hemoglobin & glucose
↑ HbA1c readings
T/F: Caution should be used when interpreting the HbA1c results from patients with conditions such as Hemolytic anemia or other hemolytic diseases, Homozygous sickle cell trait, and pregnancy
T
T/F: HbF can cause false increase in HbA1c
T
T/F: Caution should be used when interpreting the HbA1c results from patients with conditions such as Blood loss, Polycythemia, and Iron deficiency
T
Hemolytic disease = _ HbA1c
↓
What are the Hgb variants & vitamins that causes false decrease in HbA1c?
HbC
HbS
Vit C
Vit F
LIMITATIONS OF THE TEST
T/F: Coagulated or hemolyzed samples cannot be used
T
LIMITATIONS OF THE TEST
T/F: Diluted samples can be used
F; cannot
LIMITATIONS OF THE TEST
T/F: If the sample has a hemoglobin value below 6.0 g/dL or above 20.0 g/dL
T
Interpret
Hemoglobin value = >20.0 g/dL
Polycythemia
Interpret
Hemoglobin value = <6.0 g/dL
Anemia
