Endocrine

Question 1

Signs of McCune-Albright syndrome

Answer 1

Peripheral precocious puberty with premature vaginal bleeding and breast development
Irregular cafe-au-lait macules
Fibrous dysplasia of bone

Question 2

Why are obese children at risk of precocious development?

Answer 2

Adiposity –> excess insulin production –> stimulates adrenal glands to produce sex hormones

Question 3

What are some causes of central precocious puberty?

Answer 3

Idiopathic
Hypothalamic glioma
Pituitary hamartoma

Question 4

MEN2B

Answer 4

Medullary thyroid cancer (calcitonin)
Pheochromocytoma
Mucosal neuromas/marfanoid habitus

Caused by germline RET mutation

Question 5

Beckwith-Wiedemann syndrome -signs

Answer 5

Overgrowth disorder to late childhood with predisposition to neoplasms
Chromosome 11p15 –> IGF2-related genes

Fetal macrosomia and hyperinsulinemia
Macroglossia
Hemihyperplasia
Medial abdominal wall defects

Question 6

What testing should those with Beckwith-Wiedemann or isolated hemihyperplasia undergo?

Answer 6

Abdominal ultrasound (q3months from birth to age 4)
AFP (Hematoblastoma) (q3months from birth to age 4)
Renal ultrasound (Wilms tumor) (q3months from age 4-8)

Question 7

What is Gaucher disease?

Answer 7

Glucocerebrosidase deficiency - accumulation in macrophages of liver, spleen, bone marrow –> bone pain, cytopenia
Splenomegaly

Question 8

G6P deficiency features

Answer 8

Glycogen buildup in ligver –> lactic acidosis
Hypoglycemia –> seizures
Hyperuricemia
Hyperlipidemia
Protuberant abdomen from hepatomegaly
Doll-like face with rounded cheeks, thin extremities, short stature

Question 9

What is the most common cause of congenital hypothyroidism?

Answer 9

Thyroid dysgenesis

Question 10

What salt wasting abnormalities do you see in congenital adrenal hyperplasia?

Answer 10

Hyponatremia, hyperkalemia
Seen at 1-2 weeks of life

Question 11

Diagnosis and treatment for neonatal thyrotoxicosis
Danger if not treated

Answer 11

Maternal anti-TSH receptor antibodies >=500% normal

Methimazole + beta-blocker for symptomatic patients

Prevents adverse effects on developing nervous system (growth retardation, developmental/behavioral problems)

Question 12

What is the most common glycogen storage disease? Signs/symptoms in newborn?

Answer 12

von Gierke disease (GSD type I)

Hypoglycemia in newborns
Hepatomegaly
Severe acidosis

Question 13

Excessive endogenous glucocorticoids affect GnRH how?

Answer 13

Suppresses its release, causing low FSH and LH

Question 14

Which enzyme deficiency is in classic congenital adrenal hyperplasia?

Answer 14

21-hydroxylase deficiency (autosomal recessive)

Question 15

Gaucher disease

Krabbe disease

Answer 15

Gaucher - glucocerebrosidase deficiency - lipids build up in liver, spleen, bone marrow —> anemia, thrombocytopenia, hepatosplenomegaly

Krabbe - galactocerebrosidase deficiency - cannot make myelin, leading to nerve damage —> developmental regression, hypotonia, areflexia

Question 16

Hurler syndrome

Answer 16

Mucopolysaccharidoses - lysosomal hydrolase deficiency - coarse facial features, inguinal or umbilical hernias, corneal clouding, hepatosplenomegaly

Question 17

Phenylketonuria - which enzyme? Symptoms? Diagnosis? Treatment?

Answer 17

Phenylalanine hydroxylase deficiency - cannot metabolize phenylalanine to tyrosine –> phenylalanine accumulates in brain –> disrupt neuronal development and increase oxidative stress –> irreversible neurologic injury

Asymptomatic at birth
Microcephaly, seizures, poor feeding
Eczema, hypopigmentation, musty body odor

Diagnosis in symptomatic patient with serum amino acid analysis showing hyperphenylalaninemia

Avoiding protein-rich foods

Question 18

What is a complication of Wilson disease affecting the kidneys?

Answer 18

Fanconi syndrome - proximal tubular dysfunction - due to renal copper deposition

Question 19

Glucagon can be used as rescue for what heart medications?

Answer 19

Beta blocker, CCB - activates adenylate cyclase, which increases intracellular calcium and improves cardiac contractility

Question 20

What might be a main presenting sign of celiac disease?

Answer 20

Growth delay (eg weight loss, poor linear velocity)
Diarrhea only present in 2/3 of patients

Question 21

How to distinguish between constitutional growth delay and familial short stature?

Answer 21

Constitutional: Puberty growth spurt delayed, bone age delayed relative to chronological age, but eventually normal growth spurt and normal adult height

Familial: Bone age correlates with chronological age, one or both parents short

Question 22

Poorly controlled maternal diabetes causes hypomagnesemia; how does this lead to jitters in neonate?

Answer 22

Osmotic diuresis –> loss of magnesium –> fetus also has low magnesium –> PTH suppression and low calcium levels in neonate

Hypocalcemia –> jitters, respiratory symptoms (e.g. apnea, stridor from laryngospasm, wheezing from bronchospasm), seizures

Hypoglycemia is more commonly the cause of jitters

Question 23

What is small left colon syndrome?

Answer 23

Infants of diabetic mothers have small risk of this transient dysmotility condition, which may cause delayed passage of meconium >48 hr from birth

Question 24

Galactosemia - gene, signs

Answer 24

GALT (galactose 1-phosphate uridylyltransferase)

Hypoglycemia, accumulation of galactose –> seizures
Vomiting, jaundice, hepatomegaly
Poor feeding –> lethargy, dehydration, hypotonia
Risk for E. coli sepsis
Cataracts - from buildup of galactitol byproduct

Question 25

Urine reducing substances suggests what disorder?

Answer 25

Galactosemia and other errors of carbohydrate metabolism

Question 26

What is the difference between thyroglossal duct cyst and dermoid cyst?

Answer 26

They are both midline

Thyroglossal duct cyst moves with swallowing or tongue protrusion; often presents after URI
Dermoid cyst is not displaced with tongue protrusion; trapped epithelial debris