Neonatology

Question 1

A 10-day-old premature infant, born at 28 weeks of gestation, has apnea with bradycardia and desaturation after having been weaned off the ventilator. Physical examination is within normal limits. Head ultrasound and cardiac echo are normal. The infant is tolerating feeds with no spitups.

What is the best treatment for this infant?

Answer 1

Caffeine
Explanation
Apnea is a common problem in premature infants, especially those born at < 32 weeks of gestation. The drug of choice for apnea of prematurity is a methylxanthine, preferably caffeine. It is used to stimulate respiratory drive.

Question 2

A young woman with a history of chronic cocaine abuse presents to the emergency department with abdominal pain. She is diagnosed with being pregnant and is found to be in labor.
Identify the main potential risk factor for the infant.

Answer 2

Premature delivery
Explanation
Cocaine use during pregnancy also increases the risk of miscarriage and stillbirth. If used near delivery, cocaine can increase the risk of placental abruption and intracranial hemorrhage. Infants born to chronic users during pregnancy are frequently jittery, irritable, and tremulous and have muscle rigidity.

Question 3

Excessive hyperthermia from prolonged use of hot tubs during pregnancy increases the risk of what congenital defect?

Answer 3

Answer
Neural tube defects
Explanation
Extensive hyperthermia for prolonged periods during days 14–30 after conception increases the risk of this abnormality.

Question 4

A newborn presents after a difficult delivery with:

Paralysis of the right shoulder and arm
Right arm is held alongside the body in internal rotation (“waiter’s tip” position).
What is the diagnosis?

Answer 4

Answer
Erb palsy
Explanation
Erb palsy occurs when there is significant lateral traction during delivery, resulting in damage to the upper part of the brachial plexus—particularly the 5th and 6th cervical roots. This results in paralysis of the shoulder and arm. Most resolve spontaneously.

Question 5

When should universal screening for vaginal and rectal group B Streptococcus (GBS) be conducted in pregnant women?

Answer 5

Answer
Between 36 0/7 and 37 6/7 weeks of gestation
Explanation
Although greatly reduced since the advent of intrapartum antibiotic prophylaxis in 1996, GBS remains a leading cause of neonatal infection. According to the 2019 AAP/ACOG guidelines for the prevention of perinatal GBS disease in pregnancy, 36 0/7–37 6/7 weeks of gestation is the optimal timing for prenatal GBS screening.

Question 6

If an infant presents with meconium ileus, what diagnosis should you always consider?

Answer 6

Cystic fibrosis (CF)
Explanation
Meconium ileus is a lower small bowel obstruction that results from impaction due to meconium. 80–90% of neonates with meconium ileus have CF, while approximately 20% of all patients with CF present with meconium ileus as neonates. Up to 50% of cases of meconium ileus in neonates are complicated by volvulus, intestinal atresia, or perforation. Look for CF by genetic testing for all infants with meconium ileus. Refer to Pediatric Pulmonology or Cystic Fibrosis center for sweat testing, management and long-term follow-up

Question 7

What type of tumor is associated with a white pupillary reflex (leukocoria) in a newborn?

Answer 7

Retinoblastoma
Explanation
Leukocoria is also associated with chorioretinitis and advanced retinopathy of prematurity.

Question 8

A postterm newborn presents with:

History of meconium-stained amniotic fluid
Acute respiratory distress
Displaced point of maximal cardiac impulse
What is the most likely cause of the child’s respiratory distress?

Answer 8

Pneumothorax
Explanation
Pneumothorax due to a meconium aspiration is much more common in postterm newborns with a history of meconium staining of the amniotic fluid. It is clinically very important to recognize because it can lead to rapid decompensation, and even death, if not recognized and addressed; so, the scenario is frequently found as an exam question.

Question 9

You are observing the fetal heart rate (FHR) monitor. There is a fall in the FHR at the beginning of the contraction peak, with the return of the FHR only after the contraction has ended.

What is this describing, and how should you react?

Answer 9

Late decelerations; check fetal pH.
Explanation
Late decelerations are a fall in FHR—typically at the beginning or after the peak of the uterine contraction—with the return of the FHR only after the contraction has ended. All late decelerations are considered potentially ominous. If persistent, evaluate further with a measurement of fetal pH.

Question 10

A 12-hour-old infant presents with:

Enlarged posterior fontanelle
Umbilical hernia
Jaundice
What is the most likely diagnosis?

Answer 10

Hypothyroidism
Explanation
This combination is classic for hypothyroidism. Do not forget that an enlarged or persistent posterior fontanelle is also associated with hydrocephalus.

Question 11

At the newborn examination, you note a collection of edematous fluid and blood in the soft tissue of the skull. The edema crosses suture lines and the midline of the skull.

What is the most likely diagnosis?

Answer 11

Answer
Caput succedaneum
Explanation
Caput succedaneum is due to the forces of labor as the presenting part is pushed through the birthing process. The incidence is increased with prolonged labor and vacuum extraction. The caput is above the periosteum, which allows the edema to cross suture lines and the midline. Skull x-rays are not indicated and the caput will resolve over several days. While blood crossing suture lines can be concerning for subgaleal hemorrhage, that would be found at the nape of the neck rather than the midline of the skull.

Question 12

A 5-year-old presents with the following:

Shortened palpebral fissures
Epicanthal folds
Hypoplastic nasal root
Short, upturned nose
Hypoplastic philtrum
Thin upper lip
Midface hypoplasia
Weight < 10th percentile
Learning problems
What is the most likely diagnosis?

Answer 12

Answer
Fetal alcohol syndrome
Explanation
To diagnose fetal alcohol syndrome (FAS), you must have findings in each of these 3 clinical areas:

Characteristic facial features (at least 2)
Prenatal or postnatal growth restriction
Central nervous system abnormality
Sometimes definitive diagnosis is not made until the child is at least 4–8 years of age because the face is best assessed at this age and developmental evaluation is necessary.

Question 13

A 1-week-old infant in the NICU, who was born at 28 weeks of gestation, presents with:

Abdominal distention
Feeding difficulties
Emesis
Heme-positive stools
Plain abdominal film showing gas accumulation in the submucosa of the bowel wall
What is the diagnosis?

Answer 13

Necrotizing enterocolitis (NEC)
Explanation
NEC is an inflammatory injury of the bowel that is mainly seen in preterm infants. It is the most common intestinal emergency seen in this age group. The listed symptoms can progress to erythema and cellulitis of the abdominal wall, intestinal gangrene with perforation, and/or peritonitis. Bloody stools are seen in ~ 25% of cases. Most commonly, the distal ileum and proximal colon are affected due to the watershed vascular supply.

Question 14

An infant is found to have microcolon, also known as neonatal small left colon syndrome.

What diagnosis does the mother likely have?

Answer 14

Answer
Diabetes mellitus (DM)
Explanation
Congenital anomalies occur 2–4× more frequently in infants of diabetic mothers. Neonatal small left colon syndrome is one congenital anomaly that is associated with maternal DM. The increased risk of anomalies in infants of diabetic mothers is likely due to poor diabetes control before conception and during early pregnancy, when fetal organogenesis is occurring.

Question 15

A newborn presents with:

Diffuse, fluctuant swelling over the entire scalp
Swelling extends to the front of the ears, and the ears are pushed out laterally.
What is the most likely diagnosis?

Answer 15

Answer
Subgaleal hemorrhage
Explanation
Subgaleal hemorrhage results from bleeding behind the scalp aponeurotica. Bleeding can be significant, placing the infant at risk for hypotension, hyperbilirubinemia, and/or a consumptive coagulopathy due to massive blood loss. Hemophilia sometimes first presents with a subgaleal hemorrhage.

Question 16

What is the definition of large for gestational age (LGA)?

Answer 16

Birth weight > 90th percentile for age
Explanation
Disproportionate measurements are often a cause for concern; an LGA baby due to gestational diabetes is at risk for hypoglycemia.

Question 17

Stimulates α-adrenergic receptors
Enhances cardiac contractility
Constricts the peripheral circulation
Has β-adrenergic effects on the receptors of the heart
Increases rate and effectiveness of cardiac contraction
What neonatal resuscitation drug has these effects?

Answer 17

Answer
Epinephrine
Explanation
Be sure to know the effects of epinephrine on the different receptors and parts of the circulatory system.

Question 18

What is the definition of low birth weight (LBW)?

Answer 18

Answer
Birth weight < 2,500 grams
Explanation
An infant with a birth weight < 2,500 grams, regardless of gestational age, is considered LBW.

Question 19

What virus during pregnancy increases the risk of developing heart failure?

Answer 19

Parvovirus B19 (a.k.a. fifth disease)
Explanation
Parvovirus B19 infection in the pregnant woman between the 10th and 24th weeks of gestation can result in a 7–10% fetal risk of severe anemia, heart failure, hydrops fetalis, and death.

Question 20

A term infant with history of C-section delivery presents with tachypnea, grunting, and cyanosis. Lung examination is clear. CXR shows:

Prominent pulmonary vasculature
Fluid in the fissures/prominent interstitial lung markings
Flattening of the diaphragms/mild lung hyperexpansion
No air prominent bronchograms
Little to no reticular granularity to lung fields
What is the most likely diagnosis?

Answer 20

Transient tachypnea of the newborn (TTN)
Explanation
TTN usually occurs in late preterm infants born via C-section. They present with symptoms similar to respiratory distress syndrome (RDS), but with no air bronchograms or reticular granularity on CXR. TTN is caused by retention of lung fluid at birth, leaving excess fluid that fills the air spaces. The signs and symptoms typically resolve within 12–24 hours or, in severe cases, within 72 hours. Oxygen may be required, but usually no further intervention is necessary.

Question 21

A newborn presents after a difficult breech delivery with:

Paralysis of the right arm and hand
Right hand held in a claw-like posturing
What is the diagnosis?

Answer 21

Klumpke palsy
Explanation
Klumpke palsy most commonly occurs during breech deliveries and is caused by damage to the lower part of the brachial plexus. This involves the 8th cervical root and the 1st thoracic component of the brachial plexus. Klumpke’s is less likely to improve spontaneously than Erb palsy but still may respond to physical therapy.

Question 22

Shortly after delivery, an infant shows respiratory distress, including:

Tachypnea
Intercostal retractions
End-expiratory grunting
Cyanosis
Physical examination findings are:

Meconium staining of the skin and nails
Barrel-shaped chest
Coarse breath sounds
What is the most likely diagnosis?

Answer 22

Meconium aspiration syndrome (MAS)
Explanation
MAS remains one of the most common causes of respiratory failure in full-term newborns. The mortality rate for infants with severe MAS was traditionally higher at 4–5% but has decreased considerably with the advent of more sophisticated modes of ventilation, inhaled nitric oxide therapy, and extracorporeal membrane oxygenation. Suctioning of meconium at birth is no longer recommended, even in the nonvigorous newborn. Clear secretions using a bulb syringe or large-bore suction catheter followed by routine resuscitation steps of drying, stimulating, and administering oxygen as needed.

Question 23

A newborn presents with:

Lethargy
Hypotonia
Tremors/Jitteriness
What abnormality do you expect to find in the newborn’s laboratory results?

Answer 23

Hypoglycemia
Explanation
Intervention for hypoglycemia is generally recommended in all neonates with a plasma glucose concentration < 40 mg/dL during the first 24 hours of life and < 50 mg/dL after 24 hours of life. In addition to the listed findings, infants can present with frank seizures and cyanosis. Hypoglycemia is much more common during the first 24 hours of life in infants born to diabetic mothers (25–50% incidence).

Question 24

What is the leading cause of infant death in the U.S.?

Answer 24

Congenital malformation
Explanation
Congenital malformations account for ~ 20% of infant mortality in the U.S.

Question 25

What congenital malformation can carbamazepine and valproic acid cause?

Answer 25

Answer
Spina bifida
Explanation
Use of carbamazepine carries a < 1% risk of spina bifida when exposure occurs between 15 and 29 days after conception. Valproic acid carries a 2% risk of spina bifida when used in the first 30 days after conception. Antiseizure medications are folate antagonists, so it is imperative that mothers taking antiepileptics also take folic acid.

Question 26

What abnormalities are seen most often in infants with a single umbilical artery?

Answer 26

Renal or cardiac
Explanation
The majority of cases of single umbilical artery are isolated findings; however, congenital anomalies are present in approximately 30%. The most common abnormalities are cardiac and urogenital. Single umbilical artery is more common with twin pregnancies. If additional fetal abnormalities occur with the single umbilical artery (i.e., nonisolated single umbilical artery), the infant is at increased risk for a chromosomal abnormality, with the most frequent being trisomy 18.

Question 27

An infant is born to a mother with a positive rapid plasma reagin (RPR). The newborn has the following:

Jaundice
Hepatosplenomegaly
Rhinitis (severe)
Vesicular skin rash
Chorioretinitis
What is the best treatment?

Answer 27

Aqueous crystalline penicillin G
Explanation
These are clinical findings of congenital syphilis. All infants born to seropositive (RPR or Venereal Disease Research Laboratory) mothers require careful examination and the same nontreponemal syphilis test that was performed on the mother. Treat infants who are proven or highly likely to have congenital syphilis with aqueous crystalline penicillin G 50,000 units/kg/dose IV every 12 hours for the first 7 days of life, then every 8 hours thereafter to complete 10 days. An alternative is procaine-penicillin 50,000 units/kg/dose IM 1×/day for 10 days.

Question 28

You are called by a family about an 8-hour-old infant born at home who now has skin changes that are concerning to the mother. She notes that one side of the baby is pink, while the other side is pale. There is a sharp line of demarcation in the midline between the pink and pale sides.

What is the most likely diagnosis?

Answer 28

Answer
Harlequin color change
Explanation
Harlequin color change is a relatively common finding and has no pathologic basis. It is likely due to vasomotor instability and resolves as the infant matures. It generally occurs when affected infants lie on their sides—the lower side is reddened and pink while the upper side is pale/blanching with a sharp line of demarcation in the midline.

Question 29

A newborn presents with the following findings:

Heart rate—120 bpm
Respiration—vigorous, crying
Muscle tone—active motion
Reflex irritability—vigorous cry, cough
Color—pink body, blue limbs
What is the Apgar score for this newborn at 1 minute?

Answer 29

Answer
Apgar score is 9
Explanation
The infant gets 1 point for color and 2 points each for heart rate, respiration, reflex irritability, and muscle tone. Therefore, the total score is 9. Even though Apgar scoring is no longer formally part of NRP 8th Edition, exam questions may still ask you to calculate Apgar scores, so be familiar with the scoring system

Question 30

What should you suspect in an infant who is cyanotic, except when crying?

Answer 30

Bilateral choanal atresia
Explanation
Choanal atresia is the most common congenital anomaly of the nose and occurs in ~ 1/7,000 newborns. It is characterized by a bony (90%) or membranous (10%) septum between the nose and the pharynx, unilaterally or bilaterally. Confirm this condition by attempting to pass a small feeding tube through the nares into the hypopharynx. Confirm with CT scan.

Question 31

A newborn presents with the following:

Jitteriness
Irritability
Tremulousness
Muscle rigidity
Intracranial hemorrhages
What illicit drug used by the mother during pregnancy is most likely responsible for these findings?

Answer 31

Cocaine
Explanation
Chronic cocaine use by the mother during pregnancy results in jitteriness, irritability, tremulousness, and muscle rigidity in the infant. If these effects occur without the intracranial hemorrhages, they commonly resolve several days after birth without known long-term effects. Increased risk of placental abruption and intracranial hemorrhage are associated with cocaine use near delivery.

Question 32

Angiotensin-converting enzyme (ACE) inhibitors increase the risk of what congenital abnormalities?

Answer 32

Renal dysgenesis, oligohydramnios, and skull ossification defects
Explanation
ACE inhibitor use during the 2nd and 3rd trimesters increases the risk of these abnormalities.

Question 33

What baseline fetal heart rate (FHR) defines fetal bradycardia?

Answer 33

FHR < 120 bpm
Explanation
Fetal bradycardia is fairly common in postdate fetuses and in those with occiput posterior or transverse presentations.

Question 34

A 3-day-old girl presents with history of whitish vaginal discharge since birth that is now tinged with blood.

What is the most likely etiology?

Answer 34

Answer
Withdrawal of maternal hormones (normal)
Explanation
Whitish vaginal discharge is common in newborn girls and can persist for up to 2 months. On occasion, the discharge can be tinged with blood due to withdrawal of maternal hormones. This is normal, and no workup is required.

Question 35

Where is surfactant synthesized and stored in the fetus?

Answer 35

Answer
Pulmonary alveolar epithelial Type II cells
Explanation
Surfactant is made up of dipalmitoylphosphatidylcholine (lecithin), phosphatidylglycerol, apoproteins (surfactant proteins SP-A, -B, -C, -D), and cholesterol, and stored in lamellar bodies in the cytoplasm of pulmonary alveolar epithelial Type II cells. Mature levels of pulmonary surfactant are usually present at ≥ 35 of weeks gestation.

Question 36

An infant was born at 28 weeks of gestation. He was given surfactant at birth and intubated for acute respiratory distress. He was transitioned to nasal CPAP but had to be reintubated twice due to pneumonia and sepsis. He is now term but persistently requires oxygen. He is fluid restricted and is on a concentrated formula diet.

What is the most likely reason for his persistent oxygen requirement?

Answer 36

Answer
Bronchopulmonary dysplasia (BPD; a.k.a. neonatal chronic lung disease)
Explanation
BPD occurs most commonly in preterm infants born at < 30 weeks of gestation. It is characterized by persistent respiratory insufficiency, despite the absence and elimination of all other correctable causes. Infection and fluid overload are known risk factors for developing BPD.

Question 37

What is evaluated by measuring from the top of the uterine fundus to the symphysis pubis?

Answer 37

Answer
Fundal height
Explanation
Fundal height measurement is still very important and continues to be the simplest screening method to detect intrauterine growth restriction.

Question 38

An infant presents with the following:

Vernix is only on the back and creases.
The upper 2/3 of the ear is incurving.
The thin cartilage (pinna) springs back from folding.
Heel creases are present.
Lanugo is only present only on the shoulders.
Breast tissue is a 3- to 5-mm nodule.
Labia majora almost covers clitoris.
What is the gestational age of this infant?

Answer 38

38 weeks of gestation
Explanation
The vernix findings are only at 38–39 weeks of gestation; the upper 2/3 incurving at 36–38 weeks; pinna springing back at 36–39 weeks; heel creases at 38–41 weeks; lanugo on shoulders at 38–41 weeks; breast tissue at 3- to 5-mm nodule is 38 weeks; and the labia findings at 36–39 weeks. Best overlap of all of these is 38 weeks of gestation

Question 39

What congenital malformations are associated with taking thalidomide during pregnancy?

Answer 39

Missing arms and/or legs and ear malformations with deafness
Explanation
Thalidomide was one of the 1st drugs identified as a human teratogen. It has a 20% risk of causing limb defects in fetuses if used between 20 and 34 days of gestation.

Question 40

What scalp pH value is considered abnormal and indicates the need for immediate delivery?

Answer 40

Answer
pH < 7.20
Explanation
Normal fetal scalp blood pH is > 7.25. A scalp pH of 7.20–7.25 is considered suspicious; it should be repeated after 15–30 minutes and assessed in conjunction with the current fetal heart rate pattern and progression of labor.

Question 41

What is the definition of very low birth weight (VLBW)?

Answer 41

Birth weight < 1,500 grams
Explanation
An infant with a birth weight of < 1,500 grams, regardless of gestational age, is considered VLBW. Overall survival rates have improved steadily over many years reaching rates approaching 90% in many parts of the world.

Question 42

An infant presents with:

Persistent fetal heart rate > 180 bpm
Maternal fever
What is the most likely diagnosis?

Answer 42

Answer
Chorioamnionitis
Explanation
Infection of the amniotic fluid is known as chorioamnionitis. It is characterized by maternal fever with one or more of the following:
Fetal tachycardia (> 160 bpm for > 10 minutes after delivery)
Maternal WBC count > 15,000 in absence of steroids
Pus noted from cervical os
Biochemical or microbiological evidence of amniotic fluid infection

Question 43

What type of placenta do most identical twins (only 1 ovum before division) have

Answer 43

Diamniotic, monochorionic twin placentas
Explanation
Monochorionic membranes are thin and translucent. At delivery, these membranes can be separated easily to reveal a single chorionic surface that covers the villous tissue. This formation is referred to as diamniotic, monochorionic twin placentas. Rarely, if the twins separated before the formation of the chorionic cavity (before day 3), they could form separate diamniotic, dichorionic placentas (commonly associated with fraternal twins

Question 44

Mean pulmonary artery pressure _____ dramatically at birth.
Pulmonary blood flow _____ dramatically at birth.
Pulmonary vascular resistance _____ dramatically at birth.
Fill in the blanks using either “decreases” or “increases.”

Answer 44

Decreases; increases; decreases
Explanation
These are the changes in pressures and flow of the pulmonary vascular system as the baby transitions from in utero to breathing air.

Question 45

At a newborn’s examination, you note edema and blood over the parietal bone that does not appear to cross suture lines. You can palpate an “edge” that is finely demarcated.

What is the most likely diagnosis?

Answer 45

Cephalohematoma
Explanation
Cephalohematoma is a collection of blood under the periosteum of the outer surface of the skull. It most commonly occurs over the parietal bones and does not cross suture lines because it is below the periosteum. Most slowly resolve over a period of weeks or months and do not require x-ray evaluation.

Question 46

What baseline fetal heart rate (FHR) defines fetal tachycardia?

Answer 46

FHR > 160 bpm
Explanation
Fetal tachycardia is considered a Category 2 FHR monitoring pattern (indeterminate). It is defined as mild at 160–180 bpm and severe when > 180 bpm.

Question 47

Diethylstilbestrol (DES) is associated with increasing the risk of what cancer in girls born to mothers on this agent?

Answer 47

Vaginal adenocarcinoma
Explanation
Girls born to women who used DES prior to 12 weeks of gestation have an increased risk of vaginal adenocarcinoma at a later age. There also are reports of uterine abnormalities, vaginal adenosis, and male infertility.

Question 48

What is the definition of small for gestational age (SGA)?

Answer 48

Answer
Birth weight < 10th percentile for gestational age
Explanation
This definition includes many healthy infants! Not all SGA fetuses are pathologically growth restricted; some are just constitutionally small. Intrauterine growth restriction (IUGR) refers to a condition in which a fetus is not able to achieve its genetically determined potential size. By definition, IUGR excludes those newborns who are SGA but otherwise normal

Question 49

A newborn presents with:

Anhidrosis
Ptosis
Miosis
Enophthalmos
What is the diagnosis?

Answer 49

Horner syndrome
Explanation
Horner syndrome is caused by injury to the sympathetic fibers of the 1st thoracic nerve. Delayed pigmentation of the iris may occur, in addition to the listed findings

Question 50

A term infant in the delivery room presents with:

Tachypnea
Differential cyanosis (greater oxygen saturation in the upper body compared to the lower body)
Tricuspid regurgitation murmur (harsh systolic murmur at the left lower sternal border)
Loud, narrowly split 2nd heart sound (P2)
What is the most likely diagnosis?

Answer 50

Persistent pulmonary hypertension of the newborn (PPHN)
Explanation
PPHN occurs when pulmonary vascular resistance remains elevated after birth, causing pulmonary-to-systemic (right-to-left) shunting of blood via fetal circulatory pathways, leading to severe hypoxia. It is not a specific disease but a syndrome, which can be idiopathic or due to a number of causes, including meconium aspiration, sepsis, and pulmonary hypoplasia. Differential cyanosis is classic and is due to right-to-left shunting through the ductus arteriosus.

Question 51

Which race has the highest infant mortality rate in the U.S.?

Answer 51

Answer
Black
Explanation
In the U.S., on the sole criterion of race, infant mortality rates are highest among Black infants (10.9/1,000), followed by Native American infants (8.1), White infants (5.1), and finally, Asian and Pacific Islander infants (4.2). Neonatal mortality represents 2/3 of total infant mortality.

Question 52

A breastfed infant presents at 19 hours of life with new-onset jaundice.

Does this require immediate evaluation or is observation sufficient?

Answer 52

Answer
Immediate evaluation
Explanation
Jaundice that appears in the first 24 hours of life is always concerning and could indicate many pathologic conditions, including sepsis or hemolytic anemia. It is not due to breastfeeding.

Question 53

What does cigarette smoking most commonly cause in babies born to mothers who smoke?

Answer 53

Answer
Low birth weight
Explanation
Maternal smoking can also lead to a higher incidence of miscarriage, prematurity, and stillbirth. It is also a risk factor for sudden infant death syndrome (SIDS)

Question 54

A patient pregnant in the 3rd trimester presents with:

Evidence of hemolysis on CBC/blood smear
Elevated AST and ALT
Thrombocytopenia
What is the likely diagnosis?

Answer 54

HELLP syndrome
Explanation
HELLP syndrome is characterized by hemolysis, elevated liver enzymes, and a low platelet count. The pathogenesis of this obstetric complication is unclear, but it may be a variant of preeclampsia. Early diagnosis is critical because morbidity and mortality rates are as high as 25%.

Question 55

A newborn presents with:

Decreased breath sounds and/or bowel sounds in the chest
Scaphoid abdomen
Displaced point of maximal cardiac impulse (PMI)
What is the most likely diagnosis?

Answer 55

Congenital diaphragmatic hernia
Explanation
Congenital diaphragmatic hernia occurs when there is an incomplete formation of the diaphragm so abdominal contents enter the chest cavity, shifting the mediastinum to the contralateral side. The majority (80%) of congenital diaphragmatic hernias are on the left side of the chest. The findings listed here should steer you to this diagnosis, especially hearing bowel sounds in the chest cavity. Decreased breath sounds with a displaced PMI could be a pneumothorax, but you would not have bowel sounds in the chest or a scaphoid abdomen if that were the diagnosis

Question 56

A 1-day-old infant has the following:

Bounding peripheral pulses
Prominent apical impulse
Systolic thrill at the 2nd intercostal space
Continuous machinery-like murmur, which begins soon after S1, reaches maximal intensity at the end of systole, and wanes in late systole
What is the most likely diagnosis?

Answer 56

Answer
Patent ductus arteriosus (PDA)
Explanation
In an infant with continued hypoxia after birth, the ductus arteriosus can remain patent. Clinically, a PDA presents with the findings listed in the scenario. Be sure to know these signs! Interestingly, there is increased incidence of PDA in infants born at elevations > 3,000 feet.

Question 57

A term female infant presents with the following:

Coloboma of the iris or keyhole pupil
Respiratory distress that improves with crying
Misshapen ears
Cardiac murmur grade III/VI
Small size for age (SGA), 2100 grams
Small, underdeveloped labia
What syndrome does this newborn likely have?

Answer 57

CHARGE syndrome
Explanation
CHARGE syndrome is associated with the listed findings (in fact, the name “CHARGE” is an acronym of those findings). Note: If you see coloboma and atresia of the choanae, start looking for the other abnormalities that are part of CHARGE syndrome. The list of defects have expanded beyond the original acronym.

Key findings include:
Coloboma of the iris and/or retina
Cranial nerve abnormalities
Choanal atresia, unilateral or bilateral
Heart defects (various types)
External ear defects
Esophageal defects
Small/Absent semicircular canals with hearing loss
Genitourinary abnormalities including small or hypoplastic genitals
CHD7 gene mutations