CIULLA_CARBOHYDRATES Flashcards
Fasting blood glucose level of a hyperglycemic patient
> 100 mg/dL
Fasting blood glucose level of a hypoglycemic patient
<50 mg/dL
process required to maintain blood glucose levels during long fasts
gluconeogenesis
how long before glycogen stores are used up?
24-48 hrs
During a fast, the blood glucose level is kept constant by mobilizing ____________ stores in the liver
glycogen
hormone produced by the beta cells of the pancreatic islets of Langerhans
insulin
Where is insulin produced
beta cells of pancreatic islets of Langerhans
hormone which promotes the entry of glucose into liver, muscle, and adipose tissue to be
stored as glycogen and fat
insulin
hormone which inhibits the release of glucose from the liver
insulin
hormone synthesized by delta cells of the pancreatic islets of
Langerhans
somatostatin
where is stomatostatin produced
delta cells of the pancreatic islets of Langerhans
inhibits secretion of insulin, glucagon, and growth hormone, resulting in an increase in plasma glucose level
somatostatin
somatostatin promotes (increase/decrease) in plasma glucose level
increase
Hormones secreted by the anterior pituitary that raise blood glucose levels
Growth hormone Adrenocorticotropic hormone (ACTH)
Where is ACTH secreted
anterior pituitary
Secreted by the adrenal glands; stimulates glycogenolysis, lipolysis,
and gluconeogenesis
Cortisol
where is epinephrine secreted
medulla of the adrenal glands
secreted by the medulla of the adrenal glands. It stimulates glycogenolysis and lipolysis
Epinephrine
Epinephrine (inhibits/promotes) secretion of insulin
inhibits
Physical or emotional stress causes increased secretion of this hormone
epinephrine
Epinephrine causes (increase/decrease) in blood glucose levels
increase
Secreted by the alpha cells of the pancreatic islets of Langerhans
glucagon
where is glucagon secreted
alpha cells of pancreatic islets of Langerhans
increases blood glucose by stimulating glycogenolysis and gluconeogenesis
glucagon
thyroxine
where is thyroxine secreted
thyroid gland
increases glucose absorption from the intestines
thyroxine
T/F:
Glucose is normally present in the urine.
FALSE
Glucose is NOT normally present in the urine
Glucose is filtered by the ________ and reabsorbed by the ___________.
glomeruli, tubules
A condition wherein the blood glucose level is elevated and glucose appears in
the urine.
glucosuria
Individual’s renal threshold for glucose
160-180 mg/dL
When blood glucose reaches or exceeds renal threshold, the renal tubular transport mechanism becomes (unsaturated/saturated), which causes glucose to be excreted into the urine
saturated
condition characterized by deficiency of insulin
insulinopenia
TYPE OF DIABETES:
Characterized by insulinopenia, a deficiency of insulin
TYPE I
TYPE OF DIABETES:
Individuals require treatment with insulin to sustain life.
TYPE I
TYPE OF DIABETES:
Most individuals exhibit it as an autoimmune disorder where beta cells of the islets of Langerhans are destroyed by the body.
TYPE I
TYPE OF DIABETES:
Peak incidence is in childhood and adolescence, but it may occur at any age
TYPE I
Peak incidence of TYPE I DM
childhood and adolescence
Primary symptoms of diabetes mellitus
polydipsia
polyuria
polyphagia
Can produce excess ketones, resulting in diabetic ketoacidosis
Ketosis-prone
TYPE OF DIABETES:
Defect in insulin secretion and cellular resistance to insulin
TYPE II
TYPE OF DIABETES:
Individuals are not dependent on treatment with insulin.
TYPE II
TYPE OF DIABETES:
Individuals generally respond to dietary intervention and oral hypoglycemic agents, but some may require insulin therapy.
TYPE II
TYPE OF DIABETES:
Associated with obesity and sedentary lifestyle
TYPE II
TYPE OF DIABETES:
associated with individuals over the age of 40
TYPE II
Without exogenous insulin or oral hypoglycemic
medication, these individuals will have an elevated glucose but will not
go into diabetic ketoacidosis.
Non-ketosis prone
TYPE OF DIABETES:
Ketosis-prone
TYPE I
TYPE OF DIABETES:
Non-ketosis prone
TYPE II
onset of diabetes mellitus during pregnancy
Gestational diabetes mellitus
T/F:
After childbirth, women diagnosed with GDM generally returns to normal metabolism
TRUE
T/F:
Women who were diagnosed with GDM have an increased chance of developing Type II diabetes later in life.
TRUE
inherited diseases involving the deficiency of particular enzymes and may cause defects in the normal metabolism of glycogen
Glycogen storage diseases
ENZYME DEFICIENT IN:
von Gierke, Type I
Glucose-6-phosphatase deficiency
ENZYME DEFICIENT IN:
Pompe, type II
a-1,4-glucosidase deficiency
ENZYME DEFICIENT IN:
Cori, type III
Amylo-1,6-glucosidase deficiency
GLYCOGEN STORAGE DISEASE:
Glucose-6-phosphatase deficiency
von Gierke, type I
GLYCOGEN STORAGE DISEASE:
a-1,4-glucosidase deficiency
Pompe, type II
GLYCOGEN STORAGE DISEASE:
Amylo-1,6-glucosidase deficiency
Cori, type III
characterized by a deficiency or absence of galactokinase,
galactose 1-phosphate uridyl transferase, or uridyl diphosphate glucose-4-epimerase
Galactosemia
Enzymes deficient in galactosemia
galactokinase
galactose 1-phosphate uridyl transferase, or
uridyl diphosphate glucose-4-epimerase
disorder lacking in certain enzymes which prevent metabolism of galactose
Galactosemia
T/F:
Glycogen is found in milk as component of lactose
FALSE
Galactose
Galactosemia are generally identified in (adults, infants)
infants
most common enzyme deficient in galactosemia, which leads to excessive galactose in blood and excretion in urine
galactose 1-phosphate uridyl transferase
Normal fasting plasma glucose
<100 mg/dL
Impaired fasting glucose (IFG) levels
100-125 mg/dL
Provisional diagnosis of diabetes mellitus is done at what FPG levels
greater than or equal to 126 mg/dL
Diagnostics for the presence of DM
Casual plasma glucose level of greater than or equal to 200 mg/dL
Fasting plasma glucose greater than or equal to 126 mg/dL
Plasma glucose level of greater than or equal to 200 mg/dL of an OGTT
The American Diabetes Association (does not, does) recommend OGTT for routine clinical use
does not.
A woman who is at high risk for GDM should be tested when?
Initial screening early in pregnancy
If not found to have GDM during the initial screening, retest at 24-28 weeks of gestation
Women of average risk of GDM should be tested when?
24-28 weeks of gestation
GDM diagnostics
Plasma glucose of greater than or equal to 126 mg/dL
Casual plasma glucose of greater than or equal to 200 mg/dL
Glucose test involving oral ingestion of 100 g of glucose for pregnant women
OGTT
how many grams of glucose must be orally ingested in performing OGTT for testing GDM
100 g
Two-step approach explanation
Initial screening: 50 g oral glucose load
(random)
Plasma tested at 1 hr
OGTT performed when test value exceeds glucose threshold value of greater than or equal to 140 (or 130) mg/dL
an initial screening is performed
using a 50-g oral glucose load (time of day or time of last meal not
relevant). Plasma is tested at 1 hour.
This is called:
Glucose challenge test
List the criteria for diagnosing GDM (OGTT)
Fasting plasma glucose of >95 mg/dL
1-hr plasma glucose >180 mg/dL
2-hr plasma glucose >155 mg/dL
3-hr plasma glucose >140 mg/dL
Alternative for 100 g oral glucose load in diagnosing GDM
Use a 50g or 75g glucose load and measure glucose through the 2-hr period
Patient preparation for OGTT according to WHO
Unrestricted carbohydrate rich diet for 3 days before test with physical activity
Restrict medication on test day
12-hr fasting
No smoking
OGTT oral glucose load
Adult: 75g in 300-400 mL of water
Children: 1.75 g/kg up to 75g of glucose
GDM: 50g, 75g, 100g
T/F:
OGTT involves timed measurements of plasma glucose before and after ingesting a specific amount of glucose
TRUE
When is plasma glucose specimen collected for OGTT
Plasma glucose specimen collected fasting at 10 minutes before glucose load
2 hrs after ingestion of glucose
OGTT results based on WHO criteria:
Fasting plasma glucose 110-125 mg/dL
Impaired fasting glucose (IFG)
OGTT results based on WHO criteria:
Fasting plasma glucose level less than or equal to 126 mg/dL
2-hr plasma glucose level (OGTT) 140-199 mg/dL
Impaired glucose tolerance (IGT)
Impaired glucose tolerance criteria
Fasting plasma glucose level less than or equal to 126 mg/dL
2-hr plasma glucose level 140-199 mg/dL
OGTT results based on WHO criteria:
For Diabetes mellitus
Fasting plasma glucose level greater than or equal to 126 mg/dL
2-hr glucose greater than or equal to 200 mg/dL
3 forms of hemoglobin A
HbA1a
HbA1b
HbA1c
Main form of glycosylated hemoglobin
HbA1c
3 forms of hemoglobin A are referred to as:
Glycated/Glycosylated hemoglobin
Measurement of glycated hemoglobin reflects blood glucose levels for
the past ____________ months.
2-3
formed from the nonenzymatic, irreversible
attachment of glucose to hemoglobin A1
glycated hemoglobin
Techniques used to measure glycated hemoglobin
Affinity chromatography
Ion-exchange chromatography
High-performance liquid chromatography
Glycated hemoglobin specimen
Nonfasting blood specimen
Tube used for glycated hemoglobin test
EDTA
Glycated hemoglobin reference range
4-6% HbA1c
Effective treatment range <7% HbA1c
Measurement of fructosamine reflects blood
glucose levels for (how long) before sampling.
2-3 weeks
Techniques used to measure fructosamine
Spectrophotometric/Colorimetric methods
Affinity chromatography
High-Performance Liquid Chromatography
Ketoamine linkage forms between glucose and protein, mainly represented
by albumin. This forms _______.
Fructosamine
Fructosamine reference range
205-285 umol/L
microalbumin analysis specimen
Random urine
Measurement of albumin excretion is useful for patients with what disease?
Renal complications of DM
microalbumin analysis always requires the simultaneous analysis of _______.
creatinine
Microalbumin analysis is reported as
albumin/creatinine ratio
Microalbuminuria values
greater than or equal to 30 mg albumin/g creatinine
Methods of Measurement of Plasma Glucose
Glucose oxidase method
Hexokinase method
Reference range for plasma glucose (adult fasting)
74-99 mg/dL
normal end product of glucose metabolism
pyruvate
product of glucose metabolism under conditions of oxygen deficit (anaerobic metabolism)
lactate
aid in assessing the degree of oxygen deprivation that is occurring
lactate production & accumulation + measurement
T/F:
Change in the blood lactate level precedes a change in blood pH
TRUE
How is lactate metabolized?
liver via gluconeogenesis
caused by depressed oxygen
levels that may occur in acute myocardial infarction, congestive heart failure, shock, pulmonary edema, and so on
Type A lactic acidosis
caused by
metabolic processes that may occur in diabetes mellitus, renal disorders, liver
disease, ingestion of toxins (salicylate overdose and excess ethanol), and so on
Type B lactic acidosis
Special specimen handling for lactate
Avoid using tourniquet
Place specimen on ice
Centrifuge specimen and remove plasma
Using tourniquet in specimen collection for lactate will falsely (decrease/increase) blood lactate levels
Falsely increase.
Due to venous stasis
Tubes used for lactate measurement
Gray-top
Sodium fluoride, potassium oxalate
Lactate reference range
0.5-1.3 mmol/L