Hypoglycemia Flashcards

(43 cards)

1
Q

When does hypoglycemia occur?

A

Glucose utilization exceeds production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What tissue is absolutely dependent on glucose? What does it use when glucose not available?

A

Brain needs glucose, but uses ketones in absence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are main tissues of glucose use?

A

Brain, muscle, RBC/WBC, renal medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Sources of glucose (3)

A

Ingestion
Gluconeogenesis: long term
Glycogenolysis: exhausted 24-36 hr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Fasting hormonal response on glucose utilization: What are effects of insulin, glucagon, epinephrine, cortisol, growth hormone?

A

Insulin: Suppresses all glucose utilization
Glucagon: Glycogenolysis, gluconeogenesis
Epinephrine: Glycogenolysis, lipolysis, ketogenesis
Cortisol: gluconeogenesis
GH: lipolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens with decrease in insulin?

A

Increase in fatty acids and ketone generation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

At what plasma glucose are symptoms noticeable? Is it above or below levels for hormonal secretion

A

50-55mg/dL

This is below levels for hormonal secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Whipple’s Triad

A

Symptoms/signs compatible with hypoglycemia
Low plasma glucose
Resolution of symptoms/signs when plasma glucose restored to normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Neurogenic symptoms of hypoglycemia: Adrenergic (3) and Cholinergic (3)

A

Result of sympathetic nervous discharge in response to hypoglycemia

Adrenergic: palpitations, tremor, anxiety
Cholinergic: sweating, hunger, paresthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Neuroglycopenic Symptoms (big list)

A

Result of failure of brain function
Confusion, dizziness, fatigue, inability to concentrate, blurred vision, headache, focal neurological signs, loss of consciousness, seizures, depressed respiration, death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which symptoms come first?

A

Neurogenic precede neuroglycopenic symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the impact of previous episodes of hypoglycemia? (2)

A

Attenuate adrenergic response

Hypoglycemia-associated autonomic failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are 3 broad categories of fasting hypoglycemia?

A
  1. Insulin-mediated (too much insulin) (4)
  2. Failure of counter-regulation (too little counter) (2)
  3. Congenital error of metabolism (3)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is most common cause (broad) of persistent hypoglycemia? Is the specific cause different for adults vs. children?

A

Most common cause is hyperinsulinemia
For adults most likely due to insulinoma
For children, most likely due to congenital hyperinsulinism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are diagnostic criteria for hyperinsulinemic hypoglycemia? (5)

A
Hyperinsulinemia
High C-peptide
Hypofattyacidemia 
Hypoketonemia
Glycemic response to glucagon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Are insulinomas big or small? Usually benign or malignant? Where are they located?

A

Typically small and benign.

Usually located in pancreas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are ectopic locations for insulinomas? (5)

A

Duodenum, Meckel’s diverticulum, bile duct, ovary, omentum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Biochemical profile of insulinomas (3)

A

Elevated insulin, proinsulin (25% of circulating insulin) and C-peptide

19
Q

How are insulinomas treated?

A

Surgical resection

20
Q

What congenital syndrome is associated with congenital hyperinsulinism?

A

Beck with Wiedemann syndrome

21
Q

What is classic presentation of congenital hyperinsulinism? (3)

A

Severe neonatal hypoglycemia
Large birth weight
High glucose requirements

22
Q

Diffuse vs. Focal hyperinsulinism Treatment

A

Focal: remove affected area
Diffuse: need to use therapy

23
Q

Pharmacological Treatment for hyperinsulinemic hypoglycemia: Diazoxide–MOA and AE

A

Activates ATP-dependent K channel

Side effects: fluid retention, hypertrichosis

24
Q

Pharmacological treatment for hyperinsulinemic hypoglycemia: Octreotide–MOA and AE

A

Activates ATP dependent K channel, affects intracellular translocation of Ca, direct inhibition of insulin secretion

Tachyphylaxis, suppression of GH/TSH/ACTH, GI side effects, necrotizing enterocolitis

25
Categories of Autoimmune hypoglycemia
Bind to insulin receptor: agonists (hypoglycemia) or antagonists (hyperglycemia) Insulin antibodies (hirata's disease): fasting hypoglycemia
26
GH/Cortisol Deficiency: Clues (3)
Midline defect, microphallus, cholestatic liver disease
27
GH/Cortisol deficiency: treatment (2)
Shorten fasting, hormone replacement
28
Critical samples in GH/cortisol deficiency:
Ketone pattern
29
G6Pase deficiency: Clinical (2)
Impaired gluconeogenesis/glycogenolysis Failure to thrive, hepatomegaly
30
G6Pase deficiency: Labs (3) and test (1)
Hyperlacticacidemia, hyptertriglyceridemia, hyperuricemia Lack of glycemic response to fed glucagon stimulation test
31
G6Pase deficiency: Treatment (4)
Frequent carb-rich meals Intragastric dextrose Uncooked cornstarch No lactose/fructose
32
G6Pase deficiency: Types
Glycogen storage disease 1a | Glycogen storage 1b (10%): added neutropenia
33
F1,6BP deficiency: Clinical signs and trigger
Attacks of acidemia, hyperlacticacidemia, hyperuricemia Triggered by fasting/fructose
34
F1,6BP deficiency: Rx (2)
Limit fasting to less than 8-12 hours | No fructose/sucrose
35
Glycogen Debrancher Deficiency (GSD type 3): Clinical signs (3)
Failure to thrive, hepatomegaly, muscle weakness
36
Glycogen Debrancher Deficiency (GSD type 3): labs
Impaired glycogenolysis: hyperketonemia
37
Glycogen Debrancher Deficiency (GSD type 3): Rx (3)
Frequent low carb feeds Intragastric dextrose Uncooked cornstarch
38
Late symptoms of Glycogen Debrancher Deficiency (GSD type 3) (2)
Cardiomyopathy | Myopathy
39
Medium Chain Acyl-CoA Dehydrogenase Deficiency--FAO defect: Signs (2)
Hypoketotic hypoglycemia | Mimics Reye's syndrome
40
Medium Chain Acyl-CoA Dehydrogenase Deficiency--FAO defect: Rx (1)
Limit fasting to less than 12 hours
41
Hypoglycemia due to drugs (4)
Sulfonylureas Salicylate OD Beta-adrenergic blocking agents (no adrenergic warning signs, HHS pattern) Pentamidine for pneumocystis
42
What substance can stimulate hypoglycemia in fasting state? How does it do this?
Alcohol; by using NDH
43
DDX of Hypoglycemia based on critical sample
See chart! Know chart!