Carbohydrates Flashcards
Compounds (biomolecules) containing C, H, and O
Carbohydrates
Functional groups found in carbohydrates
C=O (carbonyl) and -OH (hydroxyl)
Major food source and energy supply for the body
Carbohydrates
The general formula for a carbohydrate
Cx(H2O)y
Different properties for the classification of carbohydrates
Size of the base carbon chain
Location of the CO function group
Number of sugar units
Stereochemistry of the compound
Carbohydrates classifications based on the number of carbons in the molecule
Trioses contain three carbons
Tetroses contain four
Pentoses contain five
Hexoses contain six
Example of carbohydrates reducing substances
Glucose
Maltose
Fructose
Lactose
Galactose
Most common non reducing carbohydrate
Sucrose
The primary energy source for brain, erythrocytes, and retina cells in human body
Carbohydrates
In order for a carbohydrate to be considered as reducing substance, they must contain _____
Active aldehyde and/or ketone group
Carbohydrates are hydrates of aldehyde or ketone derivatives based on the location of the CO functional group. True or False?
True
Two forms of carbohydrates
Aldose
Ketose
Carbohydrate that has a terminal carbonyl group (O=CH-)
Aldose
Carbohydrate that has a carbonyl group (O=C) in the middle linked to two other carbon atoms
Ketose
Known as the structural arrangement of atoms on a given molecule
Stereoisomers
If the hydroxyl group (OH) projects to the right in the Fisher projection, the sugar belongs to
Dextrorotatory series and receives the prefix D-
If the hydroxyl group (OH) projects to the left in the Fisher projection, the sugar belongs to
Levorotatory series and receives the prefix L-
The chaining of sugars relies on the formation of _____ that are bridges of oxygen atoms
Glycoside bonds
A glycosidic bond or glycosidic linkage is a type of covalent bond that joins a carbohydrate (sugar) molecule to another group, which may or may not be another carbohydrate. True or False?
True
The process of producing water molecule when two carbohydrate molecules join
Dehydration
The process of using water molecule to split carbohydrate, forming individual compounds
Hydrolysis
Simple sugars that cannot be hydrolyzed to a simpler form
Monosaccharides
Common examples of monosaccharides
Glucose
Fructose
Galactose
Sugar formed when two monosaccharide units are joined by a glycosidic linkage
Disaccharides
Common examples of disaccharides
Maltose
Lactose
Sucrose
Sugar chaining of 3 to 10 sugar units
Oligosaccharides
Sugar formed by the linkage of many monosaccharide units
Polysaccharides
Common examples of polysaccharides
Starch
Glycogen
What will happen if the bond forms with one of the other carbons on the carbohydrate other than the anomeric (reducing) carbon
The anomeric carbon is unaltered and the resulting compound remains a reducing substance
What will happen if the bond is formed with the anomeric carbon on the other carbohydrate
The resulting compound is no longer a reducing substance
Responsible for the digestion of nonabsorbable carbohydrate polymers to dextrins and disaccharides
Salivary and pancreatic amylase
Enzyme that further hydrolyze disaccharide to monosaccharides
Maltase
Enzyme that hydrolyze sucrose to glucose and fructose
Sucrase
Sugar that consists of 1 glucose, 1 fructose, and 1 galactose
Raffinose
Sugar that consists of 1 glucose, 1 fructose, and 2 galactose
Stachyose
Enzyme that hydrolyze lactose to glucose and galactose
Lactase
Venous system that returns blood from the digestive track to the liver
Hepatic portal system
The only carbohydrate to be directly used for energy or stored as glycogen
Glucose
Carbohydrates that must be converted to glucose before they can be used
Galactose
Fructose
The ultimate goal of the cell is to convert glucose to
Carbon dioxide and water
3 major metabolic pathways for carbohydrates
Embden-Meyerhof pathway
Hexose monophosphate (HMP) shunt
Glycogenesis
The first step for all three pathways requires glucose to be converted to _____ using the high energy molecule, _____
Glucose-6-phosphate; ATP
The reaction of converting glucose to glucose-6-phosphate is catalyzed by
Hexokinase
Metabolism of glucose molecule to pyruvate or lactate for production of energy
Glycolysis
Formation of glucose-6-phosphate from noncarbohydrate sources
Gluconeogenesis
Breakdown of glycogen to glucose for use as energy
Glycogenolysis
Conversion of glucose to glycogen for storage
Glycogenesis
Responsible for the straight forward production of glycogen from glucose
Glycogen synthase
Conversion of carbohydrates to fatty acids
Lipogenesis
Decomposition of fat
Lipolysis
Effect of glycolysis to plasma glucose concentration
Decreased
Effect of gluconeogenesis to plasma glucose concentration
Increased
Effect of glycogenolysis to plasma glucose concentration
Increased
Effect of glycogenesis to plasma glucose concentration
Decreased
Effect of lipogenesis to plasma glucose concentration
Decreased
Effect of lipolysis to plasma glucose concentration
Increased
Two major hormones responsible for blood glucose control
Insulin
Glucagon
Organ that produce insulin and glucagon
Pancreas
The primary hormone responsible for the entry of glucose into the cell
Insulin
Insulin is synthesized by
b-cells of islets of Langerhans in the pancreas
Insulin responds to
Increase in glucose
The only hormone that decreases glucose levels and can be referred to as a hypoglycemic agent
Insulin
The primary hormone responsible for increasing glucose levels
Glucagon
Glucagon is synthesized by
a-cells of islets of Langerhans in the pancreas
Glucagon responds to
Decrease in glucose
The hormone that increases glucose levels and can be referred to as a hyperglycemic agent
Glucagon
Two hormones produced by the adrenal gland that affects carbohydrate metabolism
Epinephrine
Glucocorticoids (cortisol)
Epinephrine is produced by
Adrenal medulla
Epinephrine is produced during
Stress
Effect of epinephrine in glucose level
Increased
How does epinephrine increase glucose levels?
Inhibits insulin secretion, increases glycogenolysis, and promotes lipolysis
Glucocorticoids primarily cortisol, are released from
Adrenal cortex (Zona fasciculata)
Hormone stimulating the release of glucocorticoids
Adrenocorticotropic hormone (ACTH)
Effect of glucocorticoids in glucose level
Increased
How does glucocorticoids increase glucose levels?
Decreases intestinal entry into the cell and increases gluconeogenesis, liver glycogen, and lipolysis
Two anterior pituitary hormones that promotes increased plasma glucose
Growth hormone
ACTH
Growth hormone is inhibited by
Increased glucose
How does ACTH increase plasma glucose levels?
Converts liver glycogen to glucose and promotes gluconeogenesis
Two other hormones that affects glucose levels
Thyroxine
Somatostatin
Thyroxine is released by
Thyroid gland
Somatostatin is produced by
d-cells of the islets of Langerhans of the pancreas
How does thyroxine affect plasma glucose levels
Increases plasma glucose levels by increasing glycogenolysis, gluconeogenesis, and intestinal absorption of glucose
How does somatostatin affect plasma glucose levels
Increases plasma glucose levels by the inhibition of insulin, glucagon, growth hormone, and other endocrine hormones
Embden-Meyerhof pathway is formally known as
Glycolysis
Hexose monophosphate (HMP) shunt is also known as
Pentose Phosphate Pathway or Phosphogluconate pathway
Metabolic pathway that allows the metabolic use of glucose to generate ATP, NADH, and several biosynthetic precursors such as 3-phosphoglycerate or pyruvate
Embden-Meyerhof pathway
Metabolic pathway for the conversion of glucose-6-phosphate to 6-phosphogluconic acid, which permits the formation of ribose-5-phosphate and NADPH
Hexose monophosphate (HMP) shunt
Metabolic pathway in which glucose-6-phosphate is converted to glucose-1-phosphate, which is then converted to uridine diphosphoglucose and then to glycogen by glycogen synthase
Glycogenesis
An increase in plasma glucose levels
Hyperglycemia
A group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both
Diabetes mellitus
Characterized by inappropriate hyperglycemia primarily a result of pancreatic islet b-cell destruction and a tendency to ketoacidosis
Type 1 DM
Includes hyperglycemia cases that result from insulin resistance with an insulin secretory defect
Type 2 DM
A type of diabetes that was retained in women who developed glucose intolerance during pregnancy
Gestational diabetes mellitus (GDM)
Other names of Type 1 DM
Insulin Dependent DM
Juvenile Onset DM
Brittle or Labile Diabetes
Ketosis-Prone Diabetes
Why is it called Juvenile Onset DM?
Because it is usually diagnosed with teens and young adults
Why is it called Brittle or Labile Diabetes?
Because it is associated with the severe and unpredictable swings in the blood glucose concentrations
Why is it called Ketosis-Prone Diabetes?
Because of the increase production of ketone bodies coming from fat metabolism
Autoantibodies causing cellular-mediated autoimmune destruction of the pancreas
Islet cell autoantibodies
Insulin autoantibodies
Glutamic acid decarboxylase autoantibodies
Tyrosine phosphatase IA-2 and IA-2B autoantibodies
Zinc transporter 8 antibody
Signs and symptoms of Type 1 DM
Polydipsia
Polyphagia
Polyuria
Rapid weight loss
Hyperventilation
Mental confusion
Possible loss of consciousness
Complications of Type 1 DM
Microvascular problems
Nephropathy
Neuropathy
Retinopathy
Management of Type 1 DM
Administration of insulin
A diabetes that has no known etiology; is strongly inherited; does not have β-cells autoimmunity; requires insulin replacement
Idiopathic type 1 diabetes
Type 2 DM os also known as
Non-Insulin Dependent DM
Maturity Onset or Adult Type DM
Stable Diabetes
Ketosis-Resistant Diabetes
Receptor-Deficient DM
Diabetes that constitutes the majority of the diabetes cases
Type 2 DM
Diabetes that constitutes only 5% to 10% of all cases of diabetes
Type 1 DM
Characteristics of Type 2 DM
Adult onset
Milder symptoms than in type I
Ketoacidosis is rare
Abnormal lipid concentration in the blood
Dyslipidemia
Complications of Type 2 DM
Macrovascular Problems
Coronary artery diseases
Cardiovascular Diseases
Microvascular Problems
Nephropathy
Neuropathy
Retinopathy
Any degree of glucose intolerance with onset or first recognition during pregnancy
Gestational Diabetes Mellitus (GDM)
Risks of GDM for infants
Respiratory Distress Syndrome
Hypocalcemia
Hyperbilirubinemia
High glucose concentration in the infant can delay the maturation of the lungs. True or False?
True
Screening for GDM should be performed during
Between 24 and 28 weeks of gestation
A condition when there is an increased Growth Hormone production by the pituitary gland
Acromegaly
Growth Hormone is a hypoglycemic agent. True or False?
False; hyperglycemic agent
A condition when there is an increased cortisol levels in the body
Cushing Syndrome
Cortisol is a hyperglycemic agent. True or False?
True
Risk factors of Type 1 DM
Genetics
Autoimmune
Environmental
Risk factors of Type 2 DM
Genetic
Obesity
Sedentary lifestyle
Race/ethnicity
PCOS (Polycystic Ovarian Syndrome)
Conditions that can result to diabetes
Genetic defects of β-cell function
Pancreatic disease
Endocrine disease
Drug or chemical induced
Insulin receptor abnormalities
Other genetic syndromes
Condition that occur after the renal tubular transporter system for glucose becomes saturated
Glucosuria
Renal threshold for glucose
160-180mg/dL
Condition that causes plasma glucose concentration to reach a plateau around 300 to 500 mg/dL (17 to 28 mmol/L)
Hepatic glucose overproduction
Describes a potassium level in blood that’s higher than normal
Hyperkalemia
According to the ADA recommendations all adults beginning at the age of _____ should be tested for diabetes every _____
45y/o; 3 years
Criteria for the diagnosis of DM
HbA1c ≥ 6.5%
FBS ≥ 126 mg/dL (≥ 7.0 mmol/L)
OGTT with a 2-hour post load (75g glucose load) level ≥ 200 mg/dL (≥ 11.1 mmol/L)
Symptoms of diabetes plus a RBS level ≥ 200 mg/dL (≥ 11.1 mmol/L)
All nondiabetic pregnant women should be screened for GDM at _____ weeks of gestation
24-28
Criteria for the diagnosis of GDM
FBS value ≥ 92 mg/dL (5.1 mmol/L)
1-hour value ≥ 180 mg/dL (10 mmol/L),
2-hour glucose value ≥ 153 mg/dL (8.5 mmol/L)
A hyperpigmentation condition wherein the skin in the leg, armpit, and groin areas have dark patches
Acanthosis nigricans
Decreased plasma glucose levels
Hypoglycemia
Extremely elevated insulin levels in patients with pancreatic b-cell tumors
Insulinoma
Diagnostic criteria for hypoglycemia
65 to 70 mg/dL (3.6 to 3.9 mmol/L) - glucagon and other glycemic factors are released
50 to 55 mg/dL (2.8 to 3.1 mmol/L) - observable symptoms of hypoglycemia appear
Diagnostic criteria for an insulinoma
Glucose level ≥ 25 mg/dL (1.4 mmol/L) coincident with an insulin level ≥ 6 μU/mL (41.7 pmol/L)
C-peptide levels ≥ 0.2 nmol/L
Proinsulin levels ≥ 5 pmol/L
B-hydroxybutyrate levels ≤ 2.7 mmol/L
Deficiency of a specific enzyme that causes an alternation of glycogen metabolism
Glycogen storage diseases
The most common congenital form of glycogen storage disease
Von Gierke disease
Correction for Von Gierke disease
Liver transplantation
Von Gierke disease is characterized by
Severe hypoglycemia that coincides with metabolic acidosis, ketonemia, and elevated lactate and alanine
GSD that does not cause hypoglycemia but does cause hepatomegaly
Glycogen debrancher enzyme deficiency
A cause of failure to thrive syndrome in infants, is a congenital deficiency of one of three enzymes involved in galactose metabolism, resulting in increased levels of galactose in plasma
Galactosemia
Correction for Galactosemia
Galactose must be removed from the diet
Deficient Enzyme in Galactosemia
Galactose-1-phosphate uridyltransferase (most common)
Galactokinase
Uridine diphosphate galactose-4-epimerase
Laboratory findings in Galactosemia
Hypoglycemia
Hyperbilirubinemia
Galactose accumulation in the blood, tissue, and urine following milk ingestion
Cause of essential fructosuria
Fructokinase deficiency
Cause of hereditary fructose intolerance
Defect in fructose-1,6-biphosphate aldolase B activity
Cause of fructose-1,6-biphosphatase deficiency
Defect in fructose-1,6-biphosphatase
Enzyme deficient in IA (Von Gierke) GSD
Glucose-6-phosphate
Enzyme deficient in IB GSD
Glucose-6-phosphate translocase
Enzyme deficient in II (Pompe) GSD
1,4-glucosidase
Enzyme deficient and tissue affected in IIIA (Cori Forbes) GSD
De Brancher; Liver and muscle
Enzyme deficient and tissue affected in IIIB GSD
De Brancher; Liver
Enzyme deficient in IV (Andersen) GSD
Amylopectinase/Glycogen branching enzyme
Enzyme deficient in V (Mc Ardle) GSD
Muscle phosphorylase
Enzyme deficient in VI (Hers) GSD
Liver phosphorylase
Enzyme deficient in VII (Tarui) GSD
Phosphofructokinase
Enzyme deficient in VIII GSD
Adenyl kinase
Enzyme deficient an tissue affected in IXA GSD
Phosphorylase kinase; Liver
Enzyme deficient in IXB GSD
Phosphorylase; Liver and muscle
Enzyme deficient in X GSD
Cyclic AMP-dependent kinase
Enzyme deficient in XI (Fanconi Bickel) GSD
Glycogen transporter-2
Enzyme deficient in 0 GSD
Glycogen synthase
Specimens used to measure glucose
Whole blood
Serum
Plasma
CSF
Pleural fluid
Urine
The glucose concentration in whole blood is approximately _____ lower than the glucose concentration in plasma
11%
Serum or plasma must be refrigerated and separated from the cells within
1 hour
Often used as an anticoagulant and preservative of whole blood for glucose determination
Sodium fluoride ions (gray-top tubes)
Fasting plasma glucose values have a diurnal variation. True or False?
True
Most commonly used specimen for glucose determination
Serum and plasma
POCT device for glucose determination
Glucometer
Conversion factor for glucose
0.0555
The most common methods of glucose analysis use the enzyme
Glucose oxidase or hexokinase
The most specific enzyme reacting with only b-d-glucose
Glucose oxidase
Glucose oxidase converts b-d glucose to
Gluconic acid
Reference method for glucose
Hexokinase method
Screening test for DM
FBS/FBG
Normal fasting glucose
70-99 mg/dL (3.9-5.5 mmol/L)
Impaired fasting glucose
100-125 mg/dL (5.6-6.9 mmol/L)
Provisional diabetes diagnosis
≥126 mg/dL (≥7.0 mmol/L)
Individual with impaired fasting glucose are under
Prediabetic state
Glucose testing that can be done anytime
RBS
Glucose testing that is done 2 hours after eating
2-hour PPBS
Most common test under GTT
Oral glucose tolerance test
Glucose tolerance test for patients with malabsorption syndrome
Intravenous glucose tolerance test (IVGTT)
In performing OGTT, the patient should be _____
Ambulatory
In OGTT, what should we do if FBG is >140mg/dL
Test should be terminated
In OGTT, what should we do if FBG is <140mg/dL
Glucose load should be given to the patient
The glucose load for adult is
75 g
The glucose load for children is
1.75g/kg body weight (up to a 75 g maximum is given)
The glucose should be dissolved in _____ of water, and ingested within _____
300 mL; 5 minutes
In OGTT, what should we do if the patient vomits?
Discontinue the test
Fasting for OGTT
8-10 hrs, not >16hrs
When (time) to perform OGTT?
Morning 7AM-9AM
In OGTT, patient is asked to consume _____ CHO per day for _____ prior to the test
150g; 3 days
Samples collected in pregnant women during OGTT
Fasting plasma glucose sample
1 hour sample
2 hours sample
Samples collected in non-pregnant patient during OGTT
Fasting sample
2 hours OGTT
Normal glucose tolerance
Two-hour PG ≤140 mg/dL (≤7.8 mmol/L)
Impaired glucose tolerance
Two-hour PG 140-199 mg/dL (7.8-11.1 mmol/L)
Provisional diabetes diagnosis (OGTT)
Two-hour PG ≥ 200 mg/dL (≥11.1 mmol/L)a
Individuals with impaired glucose tolerance are at risk of having
Diabetes (pre-diabetic state)
Is the term used to describe the formation of a hemoglobin compound produced when glucose reacts with the amino group of hemoglobin
Glycosylated hemoglobin/HbA1c
A more reliable method of monitoring long-term diabetes control over the previous 2-3 month period
HbA1c
Specimen for HbA1c
Whole blood in EDTA
For every 1% increase in HbA1c, there is a _____ change in plasma glucose
35 mg/dL (2 mmol/L)
Normal HbA1c value
4%-6%
Relationship between HbA1c formation and plasma glucose concentration
Directly proportional
Two factors determine the glycosylated hemoglobin levels
The average glucose concentration
Red blood cell life span
HbA1c result that indicates increased risk for diabetes
5.7%-6.4%
HbA1c result that indicates diabetes
≥ 6.5%
HbA1c goal for nonpregnant adults in general is
<7%
Preferred method of HbA1c measurement
Affinity chromatography
HbA1c measurement method that is temperature dependent and affected by hemoglobinopathies
Cation exchange chromatography
In cation exchange chromatography, the presence of HbF yields
False increased levels
In cation exchange chromatography, the presence of HbS yields
False decreased levels
In cation exchange chromatography, the presence of HbC yields
False decreased levels
A common point-of-care instrument HbA1c assay is based on a
Latex immunoagglutination inhibition methodology
Methods used to separate the various forms of hemoglobin
High-performance liquid chromatography (HPLC)
Electrophoresis
Fructosamine is also known as
Glycosylated albumin
Glycated albumin
Plasma protein ketoamine
Clinical use of fructosamine
Used for monitoring glucose control over the previous 3-6 weeks
Reference value for fructosamine
205-285 μmol/L
Chemical methods for glucose determination
Oxidation reduction method
Condensation method
Principle of Alkaline Copper Reduction Method
Reduction of cupric ions to cuprous ions forming cuprous oxide in hot alkaline solution by glucose
Substrate of Folin Wu Method
Cuprous ions + Phosphomolybdate
Product of Folin Wu Method
Phosphomolybdic Acid or Phosphomolybdenum Blue
Substrate of Nelson Somogyi Method
Cuprous ions + Arsenomolybdate
Product of Nelson Somogyi Method
Arsenomolybdic Acid or Arsenomolybdenum Blue
Substrate of Neocuprein Method
Cuprous ions + Neocuprein
Product of Neocuprein Method
Cuprous-Neocuprein Complex
(Yellow or Yellow Orange)
Reagent of Neocuprein Method
2,9-Dimethy-1,10-Phenantroline Hydrochloride
It is used for the detection and quantitation of reducing substances in body fluids like body and urine
Benedict’s Method (Modification of Folin Wu)
Stabilizing agent for Benedict’s Method
Citrate or tartrate
Substrate of Benedict’s Method
Copper Sulfate (blue) + glucose + heat
Product of Benedict’s Method
Brick red precipitate
Process of Alkaline Ferric Reduction Method (Hagedorn Jensen)
Reduction of a yellow ferricyanide to a colorless ferrocyanide by glucose
Principle of Alkaline Ferric Reduction Method (Hagedorn Jensen)
Inverse Colorimetry
Result of Alkaline Ferric Reduction Method when using Colorimetry
Colored complex
Result of Alkaline Ferric Reduction Method when using Inverse Colorimetry
Colorless ferrocyanide
Substrates of Ortho-toluidine (Dubowski Method)
Glucose + Aromatic Amines
Products of Ortho-toluidine (Dubowski Method)
Glycosylamine + Schiff’s base (green-colored end product)
Enzymatic methods for glucose determination
Glucose dehydrogenase method
Glucose oxidase method
Hexokinase method
Most specific enzyme in glucose determination
Hexokinase
Enzymes used in glucose dehydrogenase method
Mutarotase: to produce B-D glucose
Glucose dehydrogenase: to produce reduced form of NAD (NADH)
Diaphorase: to see colored end product (blue)
In Glucose dehydrogenase method, what is the relationship between NADH and the amount of glucose in the sample?
Directly proportional
Colorimetric Glucose Oxidase Method is also known as
Saifer Gernstenfield Method
Chromogens in Colorimetric Glucose Oxidase Method
3-methyl-2-benzothiazolinone hydrazone
N, N-dimethylaniline
Coupling enzyme under the colorimetric glucose oxidase method
Peroxidase
Interference in the colorimetric glucose oxidase method
Falsely decreased values: increased levels of uric acid, bilirubin, and ascorbic acid
Falsely increased values: bleach
Measures the rate of oxygen consumption which is proportional to glucose concentration
Polarographic Glucose Oxidase Method
Coupling enzymes under the polarographic glucose oxidase method
Catalase
Molybdate
Maximum absorption peak of NADPH
340 nm (wavelength)
Coupling enzyme under the Hexokinase method
G-6-PD
Produced by the liver through metabolism of fatty acids
Ketones
Ketones are produced when _____
The body detects a decrease in blood glucose
Types of Ketones
Acetone
Acetoacetic acid
3-β-hydroxybutyric acid
Most abundant form of ketones
3-β-hydroxybutyric acid (78%)
Acetone (2%)
Acetoacetic acid (20%)
Specimen used for ketone measurements
Fresh serum or urine
Elevated ketone levels are seen in
DM
Starvation/fasting
High-fat diets
Prolonged vomiting
GSD
Accumulation of ketones in blood
Ketonemia
Accumulation of ketones in urine
Ketonuria
Different tests for ketones
Gerhardt’s test
Sodium nitroprusside test
Enzymatic test
Principle of Gerhardt’s test
Ferric chloride reacts with acetoacetic acid to produce a red color
Principle of Sodium nitroprusside test
Sodium nitroprusside reacts with acetoacetic acid to produce a purple color
Enzymatic test for ketones
Uses 3-hydroxybutyrate dehydrogenase to detect 3-β-hydroxybutyric acid or acetoacetic acid
Defined as persistent albuminuria in two out of three urine collections of 30 to 300 mg/24 h, 20 to 200 μg/min, or an albumin–creatinine ratio of 30 to 300 μg/mg creatinine
Microalbuminuria
Clinical significance of microalbumin measurements
Useful to assist in diagnosis at an early stage and before the development of proteinuria
Clinical proteinuria or macroalbuminuria is established with an albumin–creatinine ratio
≥300 mg/24 h
>200 μg/min
≥300 μg/mg
Methods of Specimen Collection for microalbumin
Random spot collection for albumin-creatinine ratio
24-hour collection
Timed 4-hour overnight collection
Preferred method for microalbumin measurement
Random spot collection for albumin-creatinine ratio
Patient is determined to have microalbuminuria when
Two of three specimens collected within a 3- to 6-month period are abnormal
Factors that may elevate the urinary excretion of albumin
Exercise within 24 hours
Infection
Fever
Congestive heart failure
Marked hyperglycemia
Marked hypertension
The presence of autoantibodies to the b-islet cells of the pancreas is characteristic of
Type 1 diabetes
A slower autoimmune β-cell destruction that can occur in adults
Latent Autoimmune Diabetes of Adulthood (LADA) / Type 1a
Lab Findings in Hyperglycemia:
Decreased or absent insulin
Increased glucose in plasma and urine
Increased urine specific gravity
Ketones in serum and urine
Decreased blood and urine pH (acidosis)
Electrolyte imbalance
Diabetes testing recommended by ADA
Hemoglobin A1c (HbA1c),
Fasting plasma glucose
2-hour 75 g OGTT
Criteria for the testing and diagnosis of GDM: (NEW)
Fasting: > 95 mg/dL (5.3 mmol/L)
1-hour plasma glucose: ≥ 180 mg/dL (10.0 mmol/L)
2-hour plasma glucose: ≥ 155 mg/dL (8.6 mmol/L)
3-hour plasma glucose: ≥ 140 mg/dL (7.8 mmol/L)
Classification of hypoglycemia
Postabsorptive (fasting)
Postprandial (reactive)
Whipple triad
Hypoglycemic symptoms
Plasma glucose is low (< 50 mg/dL)
Symptoms are relieved by administration of glucose or glucagon
Symptoms of hypoglycemia
Increased hunger
Sweating
Nausea and vomiting
Dizziness
Nervousness and shaking,
Blurring of sight,
Mental confusion
Glucose is metabolized at room temperature at a rate of _____; at 4°C, glucose decreases by approximately _____
7 mg/dL/hour
2 mg/dL/hour
