Type 1 Diabetes Mellitus Flashcards
What are common secondary diabetes classifications?
Gestational diabetes
Congenital diabetes due to defects in insulin secretion
Cystic fibrosis related diabetes
Steroid induced diabetes
- especially prednisone
Pathogenesis of DM1
Autoimmune destruction of pancreatic B-cells
Accounts for 10% of all DM
Type 1A type 1 = 95%
- autoimmune sub classification of type 1
Type 1B type 1 = 5%
- idiopathic diabetes
- almost exclusively Asian or African origin
How to treat type 1 DM
Give insulin
Where is the highest incidence of DM1
Highest in Northern Europe, sardinia and Scandinavia (40-44/10,000)
- all other areas of Europe its decreased
- lowest is in china (1/100,000)
US = 16/100,000
Type 1 DM genetics and environmental factors
Genetics = 40%
- includes an HLA locus (DR3/DR4)
- HLA-DQB1*0302 = highly susceptible to DR3/4
- HLA-DQB1*0602 = protective against type 1 DM
Environmental = 60%
Symptoms of DM1
Patient is in a catabolic state chronically
Excess gluconeogenesis, lipolysis and proteolysis
- results In hyperglycemia, weight loss and wasting over time
- excessive urination, eating and drinking water
Real sick patients can show vomiting and fatigue
Excess cortisol symptoms may show but will be mild
- *if unregulated = DKA**
- severe dehydration, acidosis and hyperkalemia. Will result in cerebral edema and kills
What is the blood glucose concentration level usually to induce osmotic diuresis
180 mg/dL
What is the hygiene hypothesis?
As living environments improve, children are being less exposed to infectious agents which is leading to inadequate maturation of their immune system
- early exposure to pathogens in small doses is important to suppress autoimmune reactions
This hypothesis suggests that allergies, asthma and DM type 1 are increasing because of this
What types of autoantibodies are present for DM1?
GAD65
IA-2
Anti-insulin
Anti-B-cell (MOST COMMON)
Diagnosis of DM type 1
Needs one of the following
1) fasting plasma glucose = >126 mg/dL
- no intake for 8hrs minimum
2) symptoms of hyperglycemia (polyuria, polydipsia, unexplained weight loss) and random draw of plasma glucose > 200 mg/dL
3) 2-hr plasma glucose >200 during an OGTT
DKA symptoms
Look profoundly ill and dehydrated
Also the three poly symptoms, fatigue, headache, nausea, emesis and ab pain
Often shows AMS, tachycardia and kussmaul respiration’s
often has a fruity odor to their breath if long standing
will kill from Brian herniation secondary to cerebral edema
What other values other than glucose and A1C can you see in DM 1 for children?
Low venous pH and serum pCO2
- due to metabolic acidosis
Elevated BUN and loss of phosphate, calcium and potassium
- potassium total is lost but potassium in blood can still be normal or even high
Glucose will be in urine as long as glucose levels in blood are above 180 mg/dL
Adults = just use A1c
Treatment for DKA
this patient MUST be in the ICU
1) initate 10mL/kg IV saline or LR solution
- DONT overboard since it can make cerebral edema worse
2) once the fluid bolus is in, calculate the total fluid deficit based on amount of dehydration
- this total should be replaced over 48hrs (NOT TO FAST)
3) at the same time, access hyperglycemia and start and insulin drip of 0.1 unit/kg/hr based on patient
- goal is to decrease serum glucose by 50-100 mg/dL/hr
- don’t correct to fast since it can make cerebral edema worse
4) once glucose approaches 250-300 mg/dL, add dextrose to the normal saline to avoid hypoglycemia
What is the normal insulin:body weight distribution required for insulin therapies in DM1?
0.5-1.0 units/kg
Most need to take this 4-6 times daily or have a pump
Conventionally shows 2/3 total insulin before breakfast and 1/3rd before dinner and bedtime
What are the treatment goals for adults with diabetes?
Get as many of the values below as possible
1) A1C = <7.0%
2) preprandial glucose = 80-130 mg/dL
3) postprandial glucose = <180 mg/dL
4) blood pressure = <140/90 mmHg
