396 DM Class Flashcards
Chap. 396 Diabetes Mellitus Diagnosis Classification and Pathophysiology
Refers to a group of common metabolic disorder that share the phenotype of hyperglycaemi
Diabetes mellitus
Factors Contributingvl to hyperglycaemia
Reduced insulin secretion
Decreased glucose utilisation
Increased glucose production
Develops as a result of autoimmunity against insulin producing beta cells, resulting in complete or near total insulin deficiency
Diabetes Mellitus type 1
Heterogenous group of disorders characterized by variable of insulin resistance, impaired insulin secretion, and increased hepatic glucose production
Type 2 diabetes mellitus
Subtypes of DM characterized by autosomal dominant inheritance, early onset of hyperglycemia usually less than 25 years of age and impaired insulin secretion
Maturity onset diabetes of the young (MODY)
Most reliable and convenient test for identifying DM in asymptomatic individuals
FPG and HbA1c
Incretin hormones that bind specific receptors on the beta cell to stimulate insulin secretion through cyclic AMP production
Glucagon like peptide 1 (GLP-1)
Glucose dependent insulintropic peptide (GIP)
Mechanism of action of incretins
Suppress glucagon production and secretion
Site of release of GLP-1
Neuroendocrine L cells of the GI tract following food intake and in the alpha cells of the pancreas
gestational diabetes mellitus
gestational diabetes mellitus
what is diagnosis if glucose tolerance is diagnosed during the first trimester of pregnancy
preexisting pregestation diabetes
what is the risk of GDM developing o DM in the next 10-20 yrs
35-60%
what is the recommended screening for the development of DM in patients with GDM
lifelong, every 3 years
has the highest incidence of type 1 DM
Scandinavia
what is the harbinger of type 2 DM
impaired glucose tolerance
what are the three broad categories of glucose tolerance
normal glucose homeostasis, impaired glucose homeostasis, DM
what is impaired fasting glucose
FPG 5.6-6.9 )100-125 mg/dl
what is impaired glucose tolerance
plasma glucose level 7.8-11 mmol or 140-199 mg/dL
values diagnostic of DM
FPG of more than 7 mmol or more than 136 mg/dl, 2hrs after glucose challenge plasma glucose more than 11 or more than 200 mg/dL, HbA1c more than 6.5%
random plasma glucose sufficient for diagnosis of DM
random plasma glucose more than 11.1 mmol or more than 200 mg/dL with classic symptoms
ADA recommendation for screening DM
age more than 45 yrs old every 3 yrs or earlier if BMI more than 25 or with additional risk factor for DM
most important regulator of metabolic equilibrium
insulin
useful marker of insulin secretion and allows discrimination of endogenous and exogenous sources of insulin in the evaluation of hypoglycemia
C peptide
indicative of beta cell dysfunction
proinsulin
key regulator of insulin secretion by the pancreatic beta cell
glucose
glucose level that stimulate insulin synthesis
glucose more than 3.9 mmol or 70 mg/dL
rate limiting step that controls glucose regulated insulin secretion
glucose phosphorylation by glucokinase
what is the secretory profile of insuline
pulsatile hormone release every 10 mins and greater oscillations about 80-150 min
Asymptomatic patient with FBS 130 mg/dl. What to do next?
in asymptomatic patients with FBS more than 126 mg/dl (more than 7 mmol); 2HPPG more than 200 mg/dl (11.1 mmol) 75 g OGTT or RBS more than 200 mg/dl with 3Ps is diagnostic of DM; repeat any of the test within 2 weeks for confirmation
when to use 75g OGTT
prior FBS 0f 100-125 mg/dl 5.6-6.9 mmol; previous diagnosis of cardiovascular disease; diagnosis of metabolic syndrome
prior stroke patient came in for screening for diabetes, what is the best screening test for this patient
75 g OGTT
what is the risk for T2DM in patient with GDM
substantial risk in next 10-20 years
when does insulin resistance during pregnancy occur
late pregnancy
True or false. In patients with GDM, there is development of impaired glucose tolerance during postpartum
False. Reverts to normal