peds15

Question 1

most common cause of congenital hypothyroidism

Answer 1

thyroid dysgenesis; absent or hypoplasia; or ectopic thyroid gland anywhere from tongue to mid-chest

Question 2

thyroid dyshormonegenesis

Answer 2

inborn errors of thyroid synthesis; cause of congenital hypothyroidism; usually presents with goiter

Question 3

pendred syndrome

Answer 3

most common thyroid dyshormonegenesis and is associatied with sensorineural hearing loss

Question 4

clinical features of hypothyroidism

Answer 4

history of prolonged jaundice and poor feeding; lethargy and constipation; large ant and post fontanelles; protruding tongue, umbilical hernia, etc.

Question 5

management of hypothyroidism

Answer 5

L-thyroxine; must start ASAP to avoid brain damage

Question 6

hashimotos disease

Answer 6

chronic lymphocytic thyroiditis; most common cause of acquired hypothyroidism; thyroid autoantibodies;

Question 7

hashitoxicosis

Answer 7

transient hyperthyroidism that may occur in some patients

Question 8

clinical features of hyperthyroidism

Answer 8

lid lag and exophthalmos; thyroid is smooth and enlarged; tachycardia, palpitations; skin is warm and flushed; tremors, delayed puberty

Question 9

most common cause of hyperthyroidism in children

Answer 9

graves disease

Question 10

anti-thyroid medications

Answer 10

PTU and methimazole both inhibit thyroid synthesis; ptu also impairs conversion of peripheral T4 to T3;

Question 11

radioactive iodine

Answer 11

can be used in adolescents noncompliant with antithyroid meds; its useresults in permanent hypothyroidism

Question 12

what releases calcium and phosphorous from bone?

Answer 12

vit D and PTH

Question 13

PTH

Answer 13

releases calcium from bone and reabsorbs calcium from kidneys; releases phophorous from bone and excretes phos from kidneys

Question 14

effect of PTH on the kidney

Answer 14

calcium and bicarb reabsorption and phos excretion

Question 15

what happens in the kidney with vit D?

Answer 15

1-alpha hydroxylase vit D made int eh kidney converts 25-OH-vit D (made in the liver) to the active 1,25-OH vit D

Question 16

pseudohypocalcemia

Answer 16

low serum albumin (like in nephrotic syndrome) lead to factitious lowering of calcium; make sure you measure ionized calcium level to verify true hypocalcemia

Question 17

clinical features of hypocalcemia

Answer 17

tetany (carpopedal spasm, laryngospasm, paresthesia), seizures

Question 18

early neonatal hypocalcemia

Answer 18

younger than 4 days of age; usually transient; hypomagnesemia may also result on hypocalcemia

Question 19

late neonatal hypocalcemia

Answer 19

older than 4 days of age; can be caused by hypoparathyroidism, diGeorge syndrome, or hyperphosphatemia

Question 20

childhood hypocalcemia

Answer 20

may be caused by hypoparathyroidism, pseudohypoparathyroidism (parathyroid resistance- would have elevated PTH), hypomagnesemia, or vit D def

Question 21

how does hypomagnesemia cause hypocalcemia?

Answer 21

interferes with PTH release

Question 22

heart finding in hypocalcemia

Answer 22

prolonged QT interval

Question 23

vit d would have what effect on calcium and what effect on phosphorous

Answer 23

decreased serum levels of both

Question 24

how to evaluate for rickets

Answer 24

radiograph of wrists or knees

Question 25

rickets

Answer 25

vit D def that results in deficient mineralizationof growing bones with a normal bone matrix

Question 26

factors that predispose to rickets

Answer 26

exclusively breastfed infants with minimal sunshine; fad diets; use of anticonvulsant meds (phenytoin, phenobarbitoal), which interfere w liver metabolism; renal or hepatic failure

Question 27

how can Gi disorders lead to rickets?

Answer 27

fat malabsorption results in vit D def (CF, celiac disease)

Question 28

vit D-dependent rickets

Answer 28

autosomal recessive, rare; enzyme def in the kidneys of 1 alpha hydroxylase vit D

Question 29

vit D resistant rickets

Answer 29

aka familial hypophosphatemia; most common form of rickets; x-linked dom; caused by renal tubular phosphorous leak, resulting in low serum phosphorous; treat with phosphate supp and vit D analog

Question 30

oncogenous rickets

Answer 30

phosphate deficient form of rickets caused by a bone or soft tissue tumor; should be considered in patients who present with bone pain or myopathy

Question 31

clinical features of rickets

Answer 31

usually in first two years of life and in adolescence; wrists, knees, and ribs affected; short stature; weight bearing bones are bowed; craniotabes, frontal bossing, delayed suture closure

Question 32

rachitic rosary

Answer 32

prominent costochondral junctions seen in rickets

Question 33

diabetes insip

Answer 33

inability to maximally concentrate the urine becase of low ADH or renal unresponsiveness to ADH

Question 34

langerhans cell histiocytosis

Answer 34

can be a causes of DI

Question 35

granulomatous disease

Answer 35

sarcoidosis, tuberculosis for example; can lead to central DI

Question 36

nephrogenic DI

Answer 36

x-linked recessive disorder

Question 37

management of central DI

Answer 37

DDAVP

Question 38

symptoms of hypoglycemia in newborns

Answer 38

lethargy, myoclonic jerks, cyanosis, apnea, or seizures

Question 39

symptoms of hypoglycemia in older children

Answer 39

tachycardia, diaphoresis, tremores, headaches, or seizures

Question 40

Transient neonatal hypoglycemia

Answer 40

usually detected by screening for high-risk infants; high risk conditions include prematurity, fetal distress, SGA and LGA

Question 41

persistent neonatal hypoglycemia

Answer 41

persists for longer than 3 days; can be caused by hyperinsulinemia, defects in carb metabolism or AA metabolism, or hormone def

Question 42

causes of hyperinsulinemia in new born

Answer 42

islet cell hyperplasia (nesidioblastosis), beckwith-weidemann syndrome

Question 43

neonate presents with hypoglycemia, microphallus, and midline defects like cleft palate

Answer 43

think congenital hypopituitarism

Question 44

what hormone def can lead to hypoglycemia?

Answer 44

GH def and cortisol def

Question 45

most common cause of hypoglycemia in kids 1-6 years old

Answer 45

ketotic hypoglycemia; occurs late morning in the presence of ketonuria and low insulin; due to inability to adapt to fasting state

Question 46

ingestions of what should be considered in ddx of hypoglycemia?

Answer 46

alcohol, oral hypoglycemic agents