Endocrinology

Question 1

What is the pathophysiology behind CAH?

Answer 1

21 hydroxylase deficiency
Decrease in cortisol results in an increase of ACTH (HPA access)
ACTH stimulates the adrenals to increase steroid hormone production

Question 2

List 3 types of hormone production that are impacted in CAH

Answer 2

Cortisol
Aldosterone
ACTH

Question 3

List 2 ways in which glucocorticoid deficiency manifests

Answer 3

Hypoglycemia
Shock

Question 4

List 3 ways in which mineralocorticoid deficiency manifests

Answer 4

Hyponatremia
Hyperkalemia
Dehydration/hypotension
headache

Question 5

List 3 ways in which CAH can present

Answer 5

ambiguous genitalia
salt wasting crisis
precocious puberty

Question 6

List 4 laboratory findings in acute salt-wasting crisis

Answer 6

Hyponatremia
Hyperkalemia
Low bicarbonate
Hypoglycemia
Metabolic acidosis

Question 7

What dermatologic finding is suggestive of CAH

Answer 7

hyperpigmentation

Question 8

List the 3 chronic medications a child with Congenital Adrenal HypERplasia (salt-wasting type) must be on

Answer 8

Hydrocortisone
Fludrocortisone (Florinef)
salt supplementation

Question 9

List 5 key management steps in the care of a child presenting with CAH Salt-wasting crisis

Answer 9

Urgent electrolytes and blood glucose
Correct hypoglycemia (administer dextrose IV and add D10 to fluids)
Correct hyperkalemia (Fluid administration- NS)
Correct acidosis (no specific treatment, bicarb if pH <6.9 and hemodynamic compromise unresponsive to inotropes)

Question 10

List 6 causes of adrenal insufficiency

Answer 10

1. CAH
   2.TB
2. Meningitis
3. congenital hypopituitarism
4. Pituitary Tumor
5. Hypothalamic tumor
6. steroid use

Question 11

How does Insulin shift K+ into cells

Answer 11

Enhances activity of Na-K-ATPase pumps
Shifts K+ from extracellular to intracellular space

Question 12

How do you dose insulin in the management of hyperKalemia

Answer 12

Regular Insulin 0.1 unit/kg IV bolus (max dose 10 units)
Give with Dextrose D10W 5ml/kg IV
Glucose administered concurrently to avoid hypoglycemia

Question 13

List 3 pathophysiologic mechanisms in DKA

Answer 13

1 Lack of insulin → Intracellular hypoglycemia →
2 → ↑ Counter regulatory hormones →
4 → Ketoacid production → Anion gap metabolic acidosis
4 Lack of insulin → Extracellular hyperglycemia → Increased osmolarity → Osmotic diuresis of water, electrolytes → Hyperosmolar dehydration, electrolyte depletion

Question 14

List 4 DKA precipitants

Answer 14

New onset insulin dependent diabetes
Insulin pump failure
Noncompliance with insulin regimen
Stressors such as infection, trauma

Insulin omission
Illness
Medications- corticosteroids, atypical antipsychotics
Illicit drugs and alcohol

Question 15

List 5 S&Sx of DKA

Answer 15

Signs of dehydration (dry mucous membranes, delayed cap refill, tachycardia, poor skin turgor)
Anorexia
Nausea
Vomiting
Abdominal pain
Decreased level of consciousness (drowsiness)
Tachycardia, poor cap refill
Hyperventilation, kussmaul breathing

Question 16

Define DKA

Answer 16

Glucose >11
Acidosis: Ph <7.3, bicarb <18
Mod or large ketonuria or b hydroxybutyrate >3

Question 17

Define Mild, Moderate and Severe DKA by laboratory criteria

Answer 17

Define Mild, Moderate and Severe DKA by laboratory criteria
Mild: venous pH <7.3 or serum bicarbonate <18 mmol/L
Moderate: venous pH < 7.2 or serum bicarbonate <10 mmol/L
Severe: pH <7.1 or serum bicarbonate <5 mmol/L

Question 18

List 3 reasons patients with DKA will have hyponatremia

Answer 18

1. Vomiting
2. serum sodium may be falsely lowered due to the osmolar contribution of hyperglycemia
3. Urinary losses (the excretion of β-hydroxybutyrate and acetoacetate obligate urine sodium losses)

Question 19

List 5 management goals in DKA care

Answer 19

1. Correct anion gap metabolic acidosis, hyperglycemia: Insulin infusion
2. Correct hyperosmolar dehydration: Intravenous fluids
3. Correct electrolyte abnormalities: e.g. Na+, Cl-, K+ supplementation
4. Avoid treatment complications: Hypoglycemia, hypokalemia, cerebral edema
5. Identify and treat potential precipitants such as infections

Question 20

Write your insulin orders for a DKA patient

Answer 20

Regular Insulin 0.1 units/kg/h to start at least 1 hour after fluid administration.

Question 21

At what point should K+ be added to the IVF while managing a DKA

Answer 21

When k is <5.5 and the patient has voided

Question 22

List 4 clinical markers that an insulin infusion can be stopped, in the management of DKA

Answer 22

Resolution of ketoacidosis
pH > 7.3
HCO3 > 15
Beta-hydroxybutyrate < 1
Closure of the Anion Gap

Question 23

List 3 risk factors for the development of Cerebral Edema in DKA

Answer 23

New onset diabetes
Age <3
Low pCo2
High BUN
treatment with bicarbonate

Question 24

3 Clinical Clues a DKA patient has Cerebral Edema

Answer 24

GCS < 13
Severe/Progressive headache
Vomiting
Focal neurological sign
Irritability/inconsolability in preverbal child
Cushing’s triad (high blood pressure, low heart rate, abnormal breathing)

Question 25

How do you manage cerebral edema in DKA?

Answer 25

Elevate head of bed, head midline
Treat with Mannitol 1g/kg IV over 15-20 minutes or 3% hypertonic saline (5ml/kg)
Consider head imaging after treatment

Question 26

What CT findings are suggestive of DKA Cerebral Edema?

Answer 26

CT findings are late, slit-like ventricles, loss grey/white differentiation

Question 27

List the diagnostic criteria for DKA Cerebral Edema

Answer 27

Diagnostic Criteria
a. Abnormal motor / verbal response to pain
b. Decorticate / cecerebrate posturing
c. CN Palsy (esp. III, IV, VI) - clinically presents as double vision
d. Abnormal neurologic respiratory pattern (ie Cheyne-Stokes respiration)
Major Criteria (any 2)
e. AMS / GCS ≤ 13
f. Sustained Bradycardia (< by 20 bmp)
g. Age inappropriate incontinence
Minor Criteria (1 Major + 2 minor)
h. Vomiting
i. HA
j. Lethargy / difficult to rouse
k. dBP > 90mmHg
l. Age < 5 years old