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Flashcards in Quiz 1: Diabetes Deck (16)
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Types Of Diabetes Diseases

• Diabetes Mellitus
• Diabetes Insipidus
• Renal Diabetes


Utilization of lab assays in diagnosis, monitoring and treatment of diabetic diseases

Detect glucose
- In urine: glycosuria (Other causes: emotional stress or pain, hyperthyroidism, alimentary hyperglycemia, and meningitis)
- In blood: Hyperglycemia, Hypoglycemia
- Detect Ketone bodies: not normally found in urine (Acetonuria, Starvation, Diabetes mellitus (type I))
Normal Fasting Blood Sugar ranges:
FBS = 70-90 mg/dl
Hyperglycemic = 120 mg/dl
Hypoglycemic = < 70 mg/dl


Diabetes Characteristics

Normal fasting blood glucose: 126 mg/dl
• Polyruria: excessive urination
• Polydypsia: excessive thirst
• Polyphagia: excessive hunger


Renal Threshold

Renal Threshold
A concentration level above which all glucose is not reabsorbed in the blood, but the excess above the threshold concentration remains in the urine; glycosuria
Normal: 150 mg/dL
Fasting: 60-100 mg/dL
D. Mellitus: >200 mg/dL


Diabetes Mellitus

Most common type of diabetes, from a low level or complete lack of the hormone insulin from the pancreas
• Both the production and metabolism of glucose is increased.
• Glucagon levels are elevated
• Fasting: glucose release is elevated = hyperglycemic
• Response to release of insulin:
- Type I diabetes or insulin resistant (pancreas secretes no insulin)
- Type II where there is (some insulin available from the pancreas)


Diabetes Insipidus

A rare chronic disease characterized by the excretion of large quantities of dilute urine without abnormal findings. The pituitary gland fails to produce the hormone vasopressin which controls reabsorption of water from the kidneys.


Renal Diabetes

A benign form of glucosuria due to a low- sugar threshold in the kidneys. Blood glucose levels are normal but the kidney fails to reabsorb the normal amount of glucose back into the blood. Glucose above the threshold is excreted in the urine.


Type I and Type II Ketoacidosis

• Type 1: tendency to produce ketones
- Absence of insulin in excess glucagon
• Type 2: insulin present, glucagon present
- Adult onset, milder symptoms
- No ketones in urine, no ketoacidosis
- Coma, vascular complications


Difference between Type I and Type II

Type 1
• No production of insulin, autoimmune destruction of Beta cells
• Usually diagnosed before age 20
• 3 “P’s” symptoms: polyuria, polydipsia, polyphagia
Type 2
• Inefficient or insufficient insulin production
• Risk factors: obesity, smoking, family history
• Oral medications
• Diagnosed later adult
• Recurring skin, gum, infections, complications
• Blurred vision
• Slow healing of wounds


Type I and Type II Treatments

• Type I DM: daily injections of insulin
• Type II DM: Insulin sensitizer (oral drugs) that stimulate the secretion of insulin, increasing glucose uptake into tissues
Long Term Monitoring: Glyosated Hemoglobin A1C


Long Term Effects of Diabetes

• Arteriosclerosis
• cardiovascular circulatory problems,
• changes in eye retina and eye cataracts,
• nervous system problems
• kidney diseases caused by overwork of removing excess glucose and water
• Gangrene may easily develop as a result of the circulatory problems


Gestational Diabetes

Lack of insulin due to blocking effect of hormones (estrogen, coritsol, human placental lactogen)
• Begins around 20-24 weeks, resolves after delivery
• The larger the placenta grows, the more of these hormones are produced, In most women the pancreas is able to make additional insulin to overcome it
Prenatal Screen
• 50 gram liquid dose of glucose given
• Blood drawn @ 1hr
• No need to fast
- 1 hr pp If blood sugar = greater than 140mg/dl, positive for Gestational Diabetes
- Follow up with 3 hr GTT


3 hr Gestational Diabetes Curves

Fasting - 105
1hr - 190
2hr - 165
3hr - 145
Fasting - 80
1hr - 120
2hr - 105
3hr – 90



Deficiency or absence of galactokinase, preventing the metabolism of galactose, leading to excessive levels in blood and urine


Glycated/glycosylated Hemoglobin

HbA1c is the main form tested
Formed by a nonenzymatic , irreversible glucose attachment to HgbA1
Reflects blood glucose for last 2-3 months


Glucose Oxidase Test

Uses reaction of glucose with glucose oxidase to create gluconic acid and hydrogen peroxide
The hydrogen peroxide reacts with reduced chromagen to give oxidized (colored) chromagen