Diabetes classification/diagnosis and Hypoglycemia Flashcards
(25 cards)
Etiologic classification of DM
I. Type I diabetes
II. Type II diabetes
III. Gestational diabetes
IV. Other specific types
I. Type I diabetes (3)
- beta cell destruction, usually leading to absolute insulin deficiency
- immune mediated, idiopathic or LADA (latent autoimmune diabetes in adults)
- markers of immune destruction (ICAs, GAD65, IA-2, IAAs, Xinc ZnT8)
Staging of type I diabetes
- Stage 1 - autoimmunity, normoglycemia, pre-symptomatic, multiple autoAb, no IGT (impaired glucose tolerance) or IFG (impaired fasting glucose)
- Stage 2 - autoimmunity, dysglycemia, pre-symptomatic, multiple autoAb, FPG (5.6-6.9), 2h-PG (7.8-11.0), A1c (5.7-6.4%)
- Stage 3 - new onset hyperglycemia, symptomatic, clinical symptoms, diabetes by standard criteria
II. Type II diabetes (4)
- progressive loss of adequate beta cell insulin secretion frequently on the background of insulin resistance
- most patients –> overweight or obese
- goes undiagnosed for many years because hyperglycemia develops slowly
- risk increases with age, obesity, lack of physical activity
III. Gestational diabetes (4)
- diabetes diagnosed in the second or third trimester of pregnancy
- indicative of underlying beta-cell dysfunction
- increased risk for later development of diabetes
- life long screening for pre-diabetes is necessary
Monogenic diabetes syndrome (2)
- all children diagnosed with diabetes in the first 6 months of life
- immediate genetic testing should be done
Criteria for the diagnosis of diabetes
FGP 7.0 mmol/L or higher
OR
2h PG 11.1 mmol/L or higher during OGTT
OR
A1C 6.5% (48 mmol/mol) or higher
OR
in a patient with classic symptoms of hyperglycemia or hyperglycemic crisis, a random plasma glucose of 11.1 mmol/l or higher
two abnormal tests results are required to make the diagnosis!
Criteria defining pre-diabetes
FPG 5.6-6.9 mmol/L
OR
2h PG 75h OGTT 7.8-11.0 mmol/L
OR
A1C 5.7-6.4% (39-47 mmol/mol)Diagnosis of gestational diabetes mellitus
- Test plasma glucose at the first prenatal visit
- FPG 5.1 mmol/ or higher - confirm diagnosis
- FPG 6.1-6.9 mmol/ - perform OGTT - Test for gestational DM at 24-28 weeks of gestation
- Fasting 5.1-6.9 mmol/l
- 1h - 10.0 mmol/l or higher
- 2h 8.5-11.0 mmol/l
When to test women for gestational DM?
- test women for pre-diabetes or diabetes at 4-12 weeks post-partum
- women with a history of gestational DM should have life long screening for the development of diabetes or prediabetes at least every 3 years
Islets of Langerhans are composed of…?
Beta cells - insulin
Alpha cells - glucagon
Delta cells - somatostatin
PP cells - pancreatic polypeptide
blood flow
beta –> alpha –> delta
Fasting plasma glucose levels
- lower limit
- lower values may occur
- 3.9 mmol/L
- prolonged fasting, strenuous exercise, pregnancy
men - doest not fall below 3 mmol/L
women - doest not fall below 1.7 mmol/L
Response to hypoglycemia (4)
- decrease insulin secretion
- increase glucagon secretion
- increase epinephrine secretion
- increase cortisol and growth hormone secretion
Classification of hypoglycemia in people with DM
Level 1 –> glucose <70 mg/dL (<3.9 mmol/L) - lower limit
-eat carbs, avoid critical tasks, repeat glucose measurements
Level 2 –> glucose <54 mg/dL (<3.0 mmol/L)
-immediate and long term consequences
Level 3 –> severe, altered physical and mental states, required assistance
Does the risk of hypoglycemia increase or decreases with an increase in HbA1c?
increase HbA1c –> decrease the risk of hypoglycemia BUT increases the risk of DM complications
Etiology of hypoglycemia
- Seemingly well individual - endogenous hyperinsulinism (insulinoma, beta cell disorders, etc…), accidental, malicious hypoglycemia
- Medicated individuals - drugs, critical illnesses, hormone deficiency, non-islet cell tumor
Insulinoma (4)
- rare pancreatic islet cell tumor
- most are solitary and benign
- manifest as fasting hypoglycemia
- sporadic or associated with multiple endocrine neoplasia type 1 (MEN1)
Whipple’s triad
-criteria that suggest a patient’s symptoms result from hypoglycemia that may indicate insulinoma
- Specific symptoms
- Low plasma glucose concentration when symptoms are present
- Relief symptoms after the plasma glucose level is raised
Insulinoma
-symptoms
Autonomic response (adrenergic symptoms) - glucose <3.1 mmol/l -sweating, weakness, tachycardia, palpitations, tremor, paresthesia, hunger, nervousness
Neuroglycopenia - glucose <2.8 mmol/l
-irritability, confusion, seizure, visual disturbance, loss of consciousness, transient focal neurologic defects
Insulinoma
- diagnosis (3)
- treatment (4)
- must differentiate between insulin mediated and non-insulin mediated fasting hypoglycemia
- perform a 72h fast test
- abnormally high serum insulin, pro-insulin and C-peptide
- operation, radiation or chemotherapy
- medications: diazoxide (inhibit insulin release), verapamil and phenytoin (inhibit insulin release), somatostatin receptor analogs - ocreotide, lancreotide
Hypoglycemia - risk factors (9)
- longer duration of diabetes
- older age
- erratic timing of meals
- exercise
- alcohol ingestion
- chronic kidney disease
- malnutrition
- lower levels of glycemia, achieved with medications
- hypoglycemia associated autonomic failure
Hypoglycemia associated autonomic failure (3)
- type 1 and longstanding type 2 DM
- defective glucose counter regulation –> inability to suppress insulin secretion, attenuated response of glucagon and epinephrine
- partly reversible
Classification of severity of hypoglycemia
Severe - administer carbs, glucagon and others
Documented symptomatic - <3.9 mmol/L
Asymptomatic - <3.9 mmol/L
Probable symptomatic - not accompanied by measurement of glucose level
Pseudo hypoglycemia - typical symptoms, <3.9 mmol/L
Hypoglycemia
-treatment
- 15-20grams of fast-acting carbs
- Retest after 15min
- If glucose remains <3.9 mmol/L, repeat 1st step
- Ingest long-acting carbs to prevent recurrence
if severe
- if IV not available –> glucagon 0.5-1mg –> not effective if glycogen stores are depleted
- IV - 25g of 50% glucose
