NeoReviews2015

Question 1

Which type of imaging is best to assess subacute stages of HIE from chronic?

Answer 1

DWI MRI within 72 hrs of life

Question 2

What is a common cause of rectal bleeding in a healthy infant?

Answer 2

Eosinophilic gastrointestinal disorders (EGID)
- food protein induced proctocolitis => eosinophilic colitis

Question 3

Which foods are most frequently associated with allergic colitis of infancy? How is this addressed if breast feeding? formula feeding?

Answer 3

cow milk proteins
soy milk proteins

Breast fed infant: alter maternal diet = eliminate dairy, soy, eggs

Formula fed = protein hydroxylate formula
(soy is not recommended bc 25% of those w/cows milk allergy will be allergic to soy)

Infants with documented cow milk protein allergy should be fed extensively hydrolyzed protein formula rather than soy formula, because 10% to 14% of these infants will also have a soy protein allergy

Question 4

What is the primary teratogenic factor for abnormal embryogenesis in diabetic pregnancies?

Answer 4

hyperglycemia
-Poor maternal glycemic control (hyperglycemia) at conception and during the first trimester of pregnancy is the main cause of major fetal malformations in diabetic pregnancies.

Question 5

Fetal ascites
Fetal VSD
Fetal US w/ventriculomegaly, periventricular calcifications

Diagnostic postnatal testing?

Answer 5

Congenital CMV
-isolation of saliva, urine, blood

Maternal Grp A strep
Maternal CMV IgG+, IgM -

Question 6

Chlorhexidine application to umbilical cord may result in…

Answer 6

delayed cord separation
(high resource settings)

Question 7

Maternal obesity is most associated with increased risk of?

Answer 7

Delivery via C-section

Also:
-Difficulty w/ epidural or spinal anesthesia
- wound infections and postoperative bleeding, deep vein thrombosis, and endometritis
-PEC/cHTN
-LGA infants

Question 8

Best feeding approach for infant with high risk for atopic disease (family history)?

Answer 8

Breast feedings w/out maternal dietary restrictions

For infants at high risk for allergies, there is evidence that exclusive breastfeeding for at least 4 months in comparison to intact cow milk–based formulas decreases the incidence of eczema and cow milk allergy in the first 2 years of age. Evidence also shows that exclusive breastfeeding for at least 3 months protects against wheezing in early life.

Question 9

What are the indications for soy based formulas?

Answer 9

-Galactosemia
-Hereditary Lactase deficiency
-previously well infants with transient secondary lactose intolerance complicating acute gastroenteritis
situations in which a vegetarian diet is preferred

Question 10

What are the components of ECF? What is the predominant electrolyte? What may cause delayed diuresis?

Answer 10

intravascular space
interstitial space

Predominant electrolyte = Na

In extremely preterm infants who receive sodium supplementation before onset of diuresis in the first days after birth
=> sodium concentration within the interstitial tissues likely remains elevated and sodium and water diuresis is impaired.

Question 11

What is the most common congenital tumor? What is the composition of this tumor? M or F?

Answer 11

teratoma

-only 2% of childhood tumors present in the neonatal period
-35-60% = sacrococcygeal region
-F:M 4:1
-derived from more than 1 embryonic layer (endoderm, mesoderm, and ectoderm), =>Ectodermal components, particularly neural tissue, predominate
=> mesodermal tissues such as fat, bone, smooth muscle, and cartilage are common
-poorly differentiated embryonic tissues and are histologically subclassified as immature. A mixture of both cystic and solid components comprises the typical SCT, with purely cystic tumors found in only 15% of cases.

Question 12

What is the risk of malignancy of a teratoma? What is the most common component contributing to malignancy? Marker?

Answer 12

-Less than 10% at birth
-Risk increases after 1 year of age, 75%
-yolk sac tumor - malignancy = marker = AFP

Question 13

Prognosis if neonate v. fetus w/sacrococcygeal teratoma?

Answer 13

Neonate = 5% mortality (may be worse pending location, size etc)

Fetus <30 wks: higher mortality
= hydrops, highly vascular = risk of arteriovenous shunting, high output cardiac failure, placentomegaly

Question 14

How do you calculate the volume of distribution?

Answer 14

Volume of distribution = dose/change in concentration

Question 15

Which lesions comprise the majority of congenital heart defects?

Answer 15

left to right shunts
-ASD/VSD

Question 16

What fetal echo finding indicates possibility of ductal dependency for pulmonary flow? systemic flow?

Answer 16

Ductal dependent pulmonary flow = reversed ductal shunting

Ductal dependent Systemic flow= reversal of flow at PFO

Question 17

What are the fetal echo findings that may indicate concern for closure of PFO/restrictive (d-TGA?) ?

Answer 17

-angle of septum primum to the atrial septum less than 30°
-bowing of the septum primum into the left atrium more than 50%
-lack of normal swinging motion of the septum primum
-hypermobile septum primum in the presence of an abnormal ductus arteriosus.

Question 18

Female with elevated 17-OHP on newborn screen and on repeat level?
=brother is healthy
=no virilization or acute illness

What test can also help identify?

Genetics?`

Answer 18

Non-classic CAH
=21 hydroxylate deficiency
=high prevalence
=nonclassic disease are noted to be associated with cortisol enzyme activity at 20% to 50% of normal, and thus excess endogenous secretion of ACTH does not cause in utero virilization

ACTH stim test can help identify cases

AR
=milder mutations of the same gene, CYP21A2, found on chromosome 6p21.3, that is implicated in all known variants of 21-OHD CAH
=symptoms usually develop later (inc. of androgen secretion)

Question 19

What are the requirements of data type for the unpaired t-test in statistical analysis?

Answer 19

t test requires :
= data from each group be normally distributed (bell-shaped curves)
=works best when the variance (scatter from the mean) is symmetrical, or not skewed, and about equal for the 2 groups

unpaired t test
= because individual subjects in the 2 groups were not matched with their counterparts for characteristics (eg, birthweight, gestational age, type of feeding) that might affect the outcome variable, growth velocity.

Question 20

If p value is NOT <0.05, is the null hypothesis accepted or rejected?

Answer 20

acceptance of the null hypothesis

ex) null hypothesis would state that any difference between the mean growth velocities observed between the 2 groups occurred because of chance alone and was not related to the presence or absence of a graphic growth chart.

Question 21

What is a Type I error?

Answer 21

type I error is rejecting a true null hypothesis
=believing the difference observed is not because of chance alone, and believing (falsely) that the intervention was associated with the outcome

Question 22

What is a Type II error?

Answer 22

type II error
=accepting the null hypothesis when it is actually false, and not recognizing a real connection between variables

=>chance alone might have been responsible for this disappointing result and not a true lack of an association between the independent and dependent variable, leading to a type II error

Question 23

Are specificity, sensitivity, and PPV related to prevalence?

Answer 23

YES

Prev = 1/(1+{[(Sens/PPV)-Sens]/(1-Spec)})

PPV =
Sens/{Sens+[(1-Spec)*(1-Prev)/Prev]}

Question 24

What syndromes are associated with aplasia cutis congenita?

Answer 24

syndromes are associated with ACC
=trisomy 13, SCALP syndrome, Setleis syndrome, and Adams-Oliver syndrome (AOS).

Question 25

What is the “collar sign”?

Answer 25

membranous ACC lesions generally have a rounded appearance

nonmembranous lesions generally have more jagged borders

Membranous ACC is usually sporadic; nonmembranous can be familial

membranous lesions are surrounded by a “collar” of hair that is unusually coarse or long compared with the rest of the scalp
=>presence of this “collar sign” suggests the possibility that the lesion is a manifestation of a neural tube defect.
=>Heterotopic brain tissue can be found within the lesion, without an underlying defect in the cranium. Alternatively, the lesion may represent a rudimentary meningocele, with meningeal tissue in the skin unassociated with brain tissue and in the absence of a bone defect.

Magnetic resonance imaging (MRI) is recommended if the defect is found in the midline and is covered by a membrane, particularly if there is a surrounding hair collar (as in the vignette).

Question 26

clinical, persistent, ultimately fatal pulmonary hypertension with histopathological findings in the lungs of veins/venules in the bronchovascular sheath, simplified alveoli, thickened septa with centralized capillaries, and the presence of thickened muscular arteries ?

Answer 26

Think….ACD
= alveolar capillary dysplasia

=there is a paucity of capillaries adjacent to the alveolar epithelium, diffuse widening of the interstitial spaces and consequential thickening of alveolar walls
=thickened intra-alveolar septae, focal patchy residual preservation of alveolar architecture, and bundling of the bronchiole, venule, and arteriole within the septum.

Question 27

Genetic pattern and gene with alveolar capillary dysplasia?

Answer 27

Alveolar capillary dysplasia has been linked to deletions of the FOX transcription factor gene cluster (FOXF1, FOXC2, FOXL1) and point mutations of the FOXF1 gene

Question 28

What are the extra pulmonary manifestations of alveolar capillary dysplasia?

Answer 28

extrapulmonary manifestations that include congenital heart defects such as cor tritriatum, and atrioventricular canal; gastrointestinal abnormalities, including malrotation, heterotaxy, imperforate anus, Hirschprung disease, and congenital diaphragmatic hernia

Question 29

What is pulmonary interstitial glycogenesis?

Answer 29

PIG
=characterized by the presence of glycogen laden cells within the interstitium of the lung
=more favorable prognosis
==>developmental abnormality rather than an inflammatory or reactive process

Clinical presentation
= tachypnea, hypoxemia, and diffuse interstitial infiltrates with overinflated lungs on chest radiographs in the first month of life

Lung biopsies
= show expansion of the interstitium by spindle-shaped cells containing periodic acid–Schiff positive diastase labile material consistent with glycogen
=Minimal or no glycogen is seen in the alveolar lining cells. There is selective dysmaturity of interstitial cells that does not seem to affect the type 2 or endothelial cell differentiation or function.

Question 30

Which gene has a role in formation of lamellar bodies?

Answer 30

ABCA3 consistently has a role in the formation of lamellar bodies.

Since ABCA3 is related to other transporters of phospholipids and cholesterol, ABCA3 is likely involved in the transport of phospholipids that are critical for surfactant function into lamellar bodies and may protect against injury and inflammation of the lung.

Defective transport of 1 or more components would be expected to lead to ineffective assembly of the structure and abnormal surfactant. Alternatively, ABCA3 could transport lipids that are deleterious to the function of surfactant out of lamellar bodies.

Question 31

What clinical finding is most indicative of in-utero or postnatal brain injury?

Answer 31

early onset of moderate neonatal encephalopathy

Question 32

What is the relationship of perinatal asphyxia and CP?

Answer 32

Most cases of perinatal asphyxia are not followed by CP, and most children diagnosed with CP did not have asphyxia. An extensive body of literature shows that only 8% to 10% of cases of CP can be attributed to intrapartum asphyxia, and there are clear criteria for making such an association.

In more than 75% of cases of CP, a single identifiable cause cannot be found, though intrapartum asphyxia (hypoxia and ischemia) is often a focus

Question 33

What type of CP is most commonly seen after acute encephalopathy?

Answer 33

spastic quadriplegia or dyskinetic type is most commonly seen after acute intrapartum hypoxic-ischemic events in full-term infants.

Other forms of CP, including the ataxic subtype, are less likely to be the result of perinatal asphyxia

Question 34

Which types of neuro imaging are most sensitive for assessment of brain injury and at what timeline?

Answer 34

Diffusion-weighted MRI performed within the first week after birth has the highest specificity for brain injury

T1/T2-weighted MRI (performed in the first 2 weeks) has the highest sensitivity.

Question 35

What are the patterns of hypoxia-ischemic injury often revealed on MRI?

Answer 35

MRI is generally advised between the fourth and eighth day after a hypoxic-ischemic event.

Two major patterns of injury are detectable on MRI:

(1) a watershed predominant pattern involving the white matter, particularly in the vascular watershed, extending to cortical grey matter when severe

(2) a basal ganglia-thalamus predominant pattern involving the deep grey nuclei and perirolandic cortex, extending to the total cortex when severe. Newborns with basal ganglia-thalamus patterns of injury have the most intensive need for resuscitation and the most severe clinical encephalopathy

By contrast, newborns with the watershed pattern have predominantly cognitive impairments that often occur without functional motor deficits

Question 36

What value reflects renal function?

Answer 36

GFR

Question 37

What is the trajectory of GFR in the fetus?

Answer 37

28->35th wk: GFR gradually increases, remains low
=> placenta maintains fluid and electrolyte balance and clearance of metabolic wastes

Question 38

What is the trajectory of GFR after birth? Why?

Answer 38

-decrease in renal vascular resistance and an increase in renal blood flow contribute to an increase in GFR
- In full-term infants, GFR increases by threefold by 24 hours after delivery, with a rapid increase in the first 2 weeks
-1 month of life: GFR is 50% of adult value, reached at 2 years
-preterm: incomplete nephron develop, lower velocity of increase

Question 39

What concept is integral in the measurement GFR?

Answer 39

Clearance = (C) of a substance (x)

C = (Ux) x (V/Px)

Ux = urinary concentration
V = urine flow rate
x = plasma concentration of a substance

Clearance of a substance is equal to its rate of glomerular filtration when the substance has the following properties
=Freely filterable through the glomerular capillary membranes (not protein-bound or sieved in the process)
=Biologically inert and neither reabsorbed nor secreted by the renal tubules
=Nontoxic and does not alter renal function

Question 40

Gold standard method of GFR estimation?

Answer 40

Inulin clearance
-freely filtered, not metabolized, reabsorbed, or secreted by the renal tubules
-can be recovered quantitatively in the urine after parenteral administration

Question 41

Most clinically relevant method of estimating GFR?

Answer 41

Pcr= plasma creatinine concentration

GFR = kL/Pcr

GFR is expressed as milliliters per minute per 1.73 m2
k = 0.45 for full-term infants
k = 0.33 for premature infants
L = body length in centimeters
Pcr = plasma creatinine concentration in milligrams per deciliter.

-creatinine is secreted into the blood at a steady rate and is freely filtered at the glomerulus, creatinine can be used as an estimate of GFR

Question 42

What is the most commonly detected prenatal abnormality? What measurement is evaluated?

Answer 42

hydronephrosis
=1% to 5% of all fetuses

anteroposterior diameter (APD) of the renal pelvis in the transverse plane is the most studied parameter for assessing ANH in utero

APD less than 4 to 5 mm will likely be associated with a low risk for postnatal intervention

APD of more than 15 mm is associated with an increased risk for postnatal interventions and urinary tract infections. Factors that affect the APD may include gestational age, hydration of mother, and the degree of bladder distention

Question 43

What is the most common cause of hydronephrosis?

Answer 43

UPJ obstruction
(utereropelvic obstruction)

US: pelvicalyceal dilation without ureteral dilation

Question 44

Differential diagnosis for hydronephrosis?

Answer 44

-transient dilation of the collecting system
-upper or lower urinary tract obstruction
-nonobstructive conditions such as vesicoureteral reflux, megaureters, and prune belly syndrome

Question 45

Renal US indicates hydroureteronephrosis without a distended bladder?

Answer 45

Hydroureteronephrosis without a distended bladder suggests possible obstruction at the ureterovesical junction

Question 46

Renal US hydroureteronephrosis (bilateral) with a distended bladder suggests…?

Answer 46

distended bladder suggests obstruction at the level of the urethra

Question 47

What renal pelvis measurements indicate transient hydronephrosis?

Answer 47

-renal pelvic dilation of less than 6 mm during the second trimester or less than 8 mm during the third trimester