Endo - 1-29 - Hypoglycemia

Front 1

Autonomic response begins at blood sugar.

And neuroglycopenia?

Back 1

<60

<40

Front 2

Autonomic responses

Back 2

tachycardia, anxiety, sweating.

Front 3

Ways to dx hypoglycemia (2)

Back 3

Whipple's triad - high sensitivity, low specificity (many people with no pathology have these sx)
Autonomic sx
Blood gluc < 60
Relief of sx with eating

Pathologic
<40 mg/dL - always associated with pathology.

Front 4

Adult brain - fuel source

Back 4

Exclusively glucose for energy needs and changes to other fuels (FFAs or ketons) slowly.

So body is set to supply glucose constantly.

Front 5

Children - fuel source

Back 5

Brain makes up greater % of total body weight. So children are often already near the maximum glucose production rate.

So children are more susc to acquired hypoglycemia during illness (a period of increased metabolism). Also more susc from toxins that interfere with gluconeogenesis (e.g. EtOH)

Front 6

Child - approach to hypoglycmia

GENETIC DISORDERS

Back 6

Errors in metab not associated with hyperinsulinism
defects in glycogenolysis,
FA metabolism - can't make NAD for gluconeogenesis
AA metabolism - can lead to liver inj or mitochon dysfunc which impairs gluconeogenesis

Errors in metab associated with hyperinsulinism
Persistent hyperinsulinemic hypoglycemia of infancy (PHHI)
all 3 are aut dom
1. GOF mutation of islet cell glucokinase - more sensitive to release insulin in response to glucose
2. GOF mitochondrial glutamate dehydrogenase - too much conversion of glutamic acid to alpha ketoglutarate. Get lots of insulin and ammonia.
3. Loss of func ot potassium channel. Similar to sulfonylureas.

Front 7

Child - approach to hypoglycmia

TRANSIENT HYPERINSULINISM

Back 7

If born to woman with poorly controlled diabetes, infants have high circ insulin levels at birth. When umb cord is removed, maternal gluc is gone and hypoglycemia occurs.

Front 8

Child - approach to hypoglycmia

MEDICATION RELATED

Back 8

Excessive insulin admin in Type 1 DM

Ingestion of ethanol - interferes with gluconeogenesis

Front 9

Child - approach to hypoglycmia

HORMONE DEFICIENCY STATES

Back 9

Isolated GH def
Isolated cortisol def
Hypopituitarism (combined def of GH and cortisol)

Front 10

General note about child - approach to hypoglycemia

Back 10

Almost never insulinoma.

Front 11

Adult hypoglycemia

DRUG/TOXIN INDUCED

Back 11

this includes factitious hypoglycemia.

Insulin, sulfonylureas.

GLP1 agonists (exenatide), metformin, DPP-4 inhibitors (acarbose), PPAR gamma agonists (thiazolidinediones), and disacch inhibitors (acarbose) don't cause hypoglycemia when used alone.

Toxins - ethanol - NAD conv to NADH but NAD needed for gluconeogenesis.
Rat poison (Vacor), beta blockers (beta-receptors normally raised blood glucose).

Front 12

Adult - hypoglycemia

While fasting - due to excessive insulin release

Back 12

Insulinoma - hard to find. within the pancrease.
Some related to Multiple Endocrine Neoplasia Type I - aut dom - tumors of parathyroid, pituitary and islet cells.

Nesidioblastosis/non insulinoma pancreatogenous hyperinsulinism - Hyperplasia of islet cells. Dx made at pathology.
Pts often have postprandial hypoglycemia (some have fasting hypoglycemia as well)

Front 13

Adult - hypoglycemia

While fasting - diseases of liver dysfunction

Back 13

Causes are sudden R sided CHF
Septic shock
Fulminant global hepatitis

Front 14

Adult - hypoglycemia

While fasting - hormone def states

Back 14

Adrenal insufficiency (less hepatic gluconeogenesis enzymes)

Hypopituitarism (absence of both GH and ACTH)
Note that this is in contrast to children, where absence of only GH can cause hypoglycmia.

Front 15

Adult - hypoglycemia

While fasting - non-insulin hormones

Back 15

Tumor producing excessive insulin like growth factor 2 (IGF-2)

Front 16

Adult - hypoglycemia

While fasting - Immunologic disorders

Back 16

Antibodies that activate the insulin receptor.

Front 17

Post-meal hypoglycemia in children

Back 17

Hyper-insulinism-hyperammonia syndrome (activating mutation of glutamate dehydrogenase enzyme)

Front 18

Post-meal hypoglycemia in adults

Back 18

Following upper abdom surgery (e.g. Roux-en-Y) - excessive release of insulin after a meal. Dumping of water in intestines to give hypotension too.
Alleviated with use of acarbose to slow gastric emptying.

Non-insulinoma pancreatogenous hypoglycemia syndrome - increase mass of islet cells.

Front 19

Is reactive hypoglycemia really a hypoglycmiea?

Back 19

NO! Fatigue/sweats/palpitations after breakfast of other meals because too many simple carbs.
Tx with acarbose.
Self-limited problem with little pathology.

Front 20

Investigate postprandial sx with a glucose tolerance test?

Back 20

No - you may induce low blood sugar with the rapid glucose ingestion.

Front 21

Things to measure simultaneously in evaluating hypoglycemia

Back 21

Glucose
Insulin
C peptide
Proinsulin

Front 22

Sulfonylureas

Back 22

will increase both insulin and C-peptide levels.

Front 23

Tumors and proinsulin

Back 23

the insulin secretion is inefficient so lots of it is proinsulin (less effective at activating the insulin receptor)

Front 24

Tx of insulinoma

Back 24

Confirm location with angiography or endoscopic US

Chemo with rapamycin is the only decent (and new) option

Front 25

Tx of NIPHS (non insulinoma pancreatic hypoglycemic syndrome) or persistent hyperinsulinemic hypoglycemia of infancy (PHHI)

Back 25

pacreatectomy - 90% of total removal.

this makes the pt have Type 1 Diabetes

Front 26

good flow chart in notes

Back 26

AADSF

Front 27

With factitious...

Back 27

C-PEPTIDE IS SUPPRESSED!!!