CLINICAL CHEMISTRY - CARBOHYDRATES

Give examples of:

• Polysaccharide

• Disaccharide

• Monosaccharide

• Reducing sugars

• Nonreducing sugars

• Polysaccharide: starch, glycogen, cellulose (>10 monosaccharides)

• Disaccharide: sucrose, lactose, maltose

→glu +glu = maltose

→glu + fruc = sucrose

→glu + galactose = lactose

• Monosaccharide - glucose, galactose, fructose

• Reducing sugars - glucose, maltose, lactose, galactose, fructose

• Nonreducing sugars - sucrose

*pancreas and salivary gland = amylase

*gut = sucrase, lactase, maltase

• only hypoglycemic hormone, beta cells of islets of langerhans of pancreas

Insulin

Insulin

• released when glucose are high

• stored in liver, fat muscle

• reciprocal relationship with glucagon

• _ = false decrease because of degrading enzyme in RBC

• _ - carbohydrates to fatty acids

• normalization of glucose: _

• released when glucose are high

• stored in liver, fat muscle

• reciprocal relationship with glucagon

• HEMOLYSIS = false decrease because of degrading enzyme in RBC

• LIPOGENESIS - carbohydrates to fatty acids

• normalization of glucose: <2 HOURS

HYPOGLYCEMIA

• decrease glucose levels - _

• criteria for diagnosis of hypoglycemia: _

• drug administration cause: (3)

• critical illness: (3)

• hyperinsulinism: _

• autoimmune hypoglycemia - insulin autoantibodies

• non beta cell tumors: (3)

• hypoglycemia of infancy and childhood: (3)

• Alimentary (reactive) hypoglycemia: (2)

• Idiopathic (functional) postprandial hypoglycemia

• DIAGNOSTIC TEST: _

• decrease glucose levels : < 0r equal to 60 mg/dL

• criteria for diagnosis of hypoglycemia: WHIPPLE'S TRIAD (hypoglycemia > intake of glucose > alleviation of symptoms)

• drug administration cause: INSULIN, SALICYLATES, ALCOHOL

• critical illness: SEPSIS, HEPATIC, RENAL FAILURE

• hyperinsulinism: CANCER

• autoimmune hypoglycemia - insulin autoantibodies

• non beta cell tumors: LEUKEMIA, LYMPHOMA, HEPATOMA

• hypoglycemia of infancy and childhood: GALACTOSEMIA, REYE'S SYNDROME, GSD

• Alimentary (reactive) hypoglycemia: POST-GASTRIC SURGERY, within 4 hours after eating meal

• Idiopathic (functional) postprandial hypoglycemia

• DIAGNOSTIC TEST: 5-HOUR GTT (hypoglycemic dip is not seen until after 3 hours, there should not be dip in glucose levels before 3 hours)

• primary hyperglycemic agent synthesized by alpha cells of pancreas

glucagon

Hyperglycemic agents

• GAGCHETS

• G - glucagon

• A - acth

• G - growth hormone

• C - cortisol

• H - human placental lactogen

• E - epinephrine/norepinephrine

• T - thyroxine / T4

• S - somatostatin

Actions of glucagon

• gluconeogenesis

• glycogenolysis

• lipolysis

Actions of Insulin

• Glycolysis

• Glycogenesis

• Lipogenesis

HYPERGLYCEMIA

• hallmark sign of DM I and II

• FBS level: _

• Causes: _

• FBS level: >126 mg/dL

• Causes:

→ stress, severe infection, dehydration, pregnancy, hemochromatosis, pancreatectomy, abnormal insulin receptor, insulin deficiency

• Iron accumulation in pancreas =

bronze diabetes mellitus

Diabetes Mellitus

• diabetes in greek: _

• mellitus in latin: _

• diabetes in greek: to siphon or pass through

• mellitus in latin: sweet

Type 1 DM

• Former names

• Insulin-dependent DM

• Juvenile Onset Diabetes Mellitus

• Brittle Diabetes

• Ketosis-prone diabetes

Type 1 DM

• Pathogenesis: _

• Peak incidence: _

• Beta cell destruction, insulinoipenia

• Most common: autoimmune disorder

• Peak incidence: childhood and adolescence

Type 1 DM

• C-peptide

→reliable indicator for pancreatic surgery and insulin secretion

• low

Type 1 DM

• symptoms

• develop abruptly - polyuria, polydipsia, polyphagia

• rapid weight loss

• complications: microvascular disorders - nephropathy, neuropathy, retinopathy

Type 1 DM

• Ketones/Ketosis

• High/Uncontrolled

Ketone Bodies

• can be used by the brain for energy thru _

• Forms: (3)

• can be used by the brain for energy thru TRICARBOXYLIC ACID CYCLE (KREB'S)

• Forms: (3)

→Beta-hydroxybutyrate (78%) - major

→Acetoacetic acid (20%)

→Acetone (2%)

Type 1 DM

• associated with HLA-_

• autoantibodies present: (4)

• associated with HLA-DR3 and HLA-DR4

• autoantibodies present:

→islet cell autoantibodies

→insulin autoantibodies - common in children

→glutamic acid decarboxylase (GAD65) autoantibodies

→tyrosine phosphatase IA-2 and IA-2B autoantibodies

Type 1 DM

• Medication

Insulin

Type 2 DM

• Former names

• Non-insulin dependent diabetes mellitus

• Adult type/maturity onset diabetes melitus (>40)

• Stable diabetes

• Ketosis-Resistant Diabetes

• Receptor-deficient DM

• GENETICIST'S NIGHTMARE

Type 2 DM

• Pathogenesis

• insulin resistant

• associated with obesity and sedentary lifestyle, PMOS, hypertensiion

Type 2 DM

• C-peptide

• low

Type 2 DM

• symptoms

• milder symptoms than type