Diabetes Mellitus Flashcards
Different criteria for diagnosis of DM (name 4)
- Fasting glucose greater than 126
- Plasma glucose greater than 200 after 2 hour GTT (75 g glucose load)
- Any plasma glucose over 200 + symptoms (polydipsia, polyuria, etc)
- HbA1c 6.5% or more
What can you measure to differentiate between T1DM and T2DM
C-peptide and insulin levels
When does glucosuria occur?
When bood glucose level is greater than renal “threshold”; often at serum level of 180 which corresponds to HbA1c of 8%
So absence of glucose on urinalysis does not exclude DM!
What other physical symptoms are more consistent with T2DM
HTN, acanthosis nigracans, obesity…all overt signs of insulin resistance
Upon initial dx of DM, and regulary after dx, what testing?
fasting lipid profile, serum creatinine and creatinine ratio, U/A, urinemicroalbumin, annual dilated eye exams, regular foot exam, ECG and thyroid dx screening with TSH (in T1DM)
General approach to treatment of DM
aimed at secondary prevention of macrovascular (CAD, cerebral/peripheral vascular dx) and microvascular (retinopathy, nephropathy, and neuropathy) complications
Pathophysiology of T1DM (aka IDDM)
not entirely known, may be autoimmune that attacks pancreatic B cells, thereby rendering body unable to produce insulin…body is then unable to metabolize glucose and carbs, so must resort to metabolizing fats…leading to ketones
DKA
syndrome characterized by hyperglycemia, high levels of serum acetone, b-hydroxybutarate, and anion gap metabolic acidosis
usually happens under stress or when person forgets to take insulin
Treatment of DKA
emergent hospitalization for IV hydration with NS, correction of acidosis and electrolyte disturbances (give K), aggessive insulin mgmt, evaluation for underlying cause
Pathophysiology T2DM (NIDDM)
insulin resistance in peripheral tissues often due to visceral adiposity and obesity…may have hyperinsulinemia then eventually less insulin
majority of cases, stronger family component
Comlications of T2DM
cardiometabolic syndrome, hyperinsulinemia, HTN, dyslipidemia, hyperglycemia, central obesity
T2DM less prone to developing ketosis and acidosis, but is more prone to ________ states due to high blood sugar
hyperosmolar
aka hyperosmolar hyperglycemic non-ketotic syndrome (HHNS)
Characteristics of HHNS
blood glucose substantially elevated (often reaching up to 1000), with elevated serum osmolarity and large fluid deficit…severe coma or death may occur due to electrolyte abnormalities, dehydration, and toxic effects of metabolic acidosis
How to treat HHNS
similar to DKA;
hospitalization, aggresive rehydration, with NS and electrolyte correction; insulin and treatment of underlying disorder
GDM (gestational DM)
increased levels of human placental lactogen (hpL), estrogen and progesterone produced by placenta antagonize insulin -> insulin resistance and carb intolerance
Maternal complications of GDM
hyperglycemia, DKA, increased UTI, increased HTN/pre-eclampsia, retinopathy
Fetal complications of GDM
congenital malformations, macrosomia, RDS, hypoglycemia, hyperbilirubinemia, hpocalcemia, polycythemia, and hydramnios
What are mothers who have GDM more at risk of after pregnancy and how to mitigate this risk
T2DM, should be screened with GTT postpartum and annual diabetic screening
When to screen for GDM and how to screen
between 24-28 weeks
first with 1hr 50 g GTT….
then if that shows greater than 140, do 3 hr 100g GTT, which takes fasting, 1hr, 2hr, and 3hr measurements…
if 2 or more abnormal values (95,180,155,140)…then that is diagnosis
How to treat GDM
strict dietary mgmt, and if necessary oral diabetic agents with or without insulin.
Once GDM is diagnosed, what must be monitored for during pregnancy
Increased surveillance for UFD (uterine fetal demise)
Goals to achieve “controlled status” in diabetic patient
- strict glycemic control with goal a1c of less than 7
- LDL
Treatment for T1DM
- insulin administration (usually short acting before meals + long acting basal insulin) via injection or pump (if labile sugar)
- strict glucose monitoring
- calorie restricted and low carb diet and exercise
First line medication of T2DM
biguanides (METFORMIN)
Biguanide mechanism
act on liver to decrease gluocse output during gluconeogenesis.
secondary: improved insulin sensitivity in liver and muscle; possible decrease in intestinal absorption of glucose
Other advatnages of metformin
no risk of hypoglycemia, good for weight loss, reduced serum insulin levels, reduction in triglycerides and LDL
Metformin side effects common and dangerous
common: nausea and diarrhea
dangerous: development of lactic acidosis caused by renal insufficency and CKD (contraindication in patients with Cr> 1.4-1.5)
Is metformin safe for pregnancy?
Yes; Cat B, also good for children older than 10
Examples of sulfonlyureas
glimepiride glyburide, glipizide
Mechanism of sulfonylureas
insulin secretagogues that stimulate pancreatic B cells to secrete insulin
