Pediatric Board Review Questions

Question 1

A 4-month old had a prolonged seizure 6 days after his 2-month well child visit. He received the standard 2-month vaccinations. He now returns for his 4-month visit. Which of the following statements is true regarding DTaP?

a. The child should no longer receive DTaP or any component of it ever again.
b. The child should no longer receive DTaP, but may receive the aP component at this visit.
c. The child should no longer receive DTaP, but may receive one of the components at 1-year of age.
d. The child may receive DTaP at this visit.
e. The child should undergo allergy testing with the individual components.

Answer 1

The answer is C, “The child should no longer receive DTaP, but may receive one of the components at 1-year of age”

DTaP CONTRAINDICATIONS:

1. ENCEPHALOPATHY or “PROLONGED” SEIZURE should trigger an alert! If a child has encephalopathy or a “prolonged” seizure within 1 week of getting DTaP, the PERTUSSIS (aP) component is contraindicated in future vaccinations. Instead, give DT. Please remember that this is possibly a reaction to the PERTUSSIS component, and not the tetanus component. Also, DO NOT order allergy testing because you may induce a seizure!
2. PROGRESSIVE NEUROLOGIC DISORDER: If a child has a neurologic disorder that is considered progressive, or has a seizure disorder that is not yet under control, then DTaP is relatively contraindicated. If the neurologic disorder has been stabilized or is no longer progressive, you MAY give DTaP.
3. OTHER RELATIVE CONTRAINDICATIONS: Having a brief seizure within 3 days, a high fever (>105°) within 48 hours, or a shock-like state within 48 hours of previous administration.
   
   • PEARL/MNEMONIC: If tested on one of these 3 relative contraindications, You are more likely to be given a case in which the child had an issue 4-7 days from the date of previous vaccination. This would make the answer clear (give DTaP!). Therefore, keeping the FOURTH day in mind as the day when the child is in the clear might help with these 3 relative contraindications.

Question 2

Name the inheritance pattern the following image most likely represents:

a. Autosomal dominant
b. Autosomal recessive
c. X-linked dominant
d. X-linked recessive

Answer 2

The answer is C, “X-linked dominant“

In an X-linked dominant disorder. Affected females may, or may not, pass on her defective X chromosome to their sons or daughters. There is NEVER male-to-male transmission AND there is ALWAYS transmission of the disorder from an affected male to his daughters (fathers will always pass on their defective X chromosome to their daughters). The latter point can help differentiate between an X-linked dominant and an autosomal dominant pedigree.

PEARLS:

• X-linked disorders are RULED OUT if you see male-to-male transmissions!
• A vignette about a male patient that discusses ANYTHING about a MATERNAL UNCLE should alert you to possible X-linked disorder.
• Most X-linked disorders are X-linked RECESSIVE. The dominant ones seem to select themselves out. These X-linked recessive disorders tend to be enzyme or protein deficiencies, thus several inborn errors of metabolism are X-linked recessive.

Question 3

An LGA baby is born after a difficult breech delivery. The patient is noted to have tachypnea. A chest X-ray is obtained and it shows unilateral diaphragmatic elevation. What is the likely etiology?

a. Abdominal trauma with hematoma
b. Asphyxia
c. Erb’s Palsy
d. Klumpke Palsy

Answer 3

The answer is C, “Erb’s Palsy”

Both ERB’S PALSY and KLUMPKE PALSY are associated with birth trauma, BREECH delivery, caesarian sections, clavicle fractures and LGA births, but ERB’s palsy is more likely to be associated with a unilateral diaphragmatic paralysis.

• PEARLS: Images of the arm/hand deformities MAY look the same. The only way to discern which palsy the child has is to evaluate the patient for specific neurologic limitations. If the baby is able to grasp, it is an ERB’S PALSY. If you note a claw hand deformity in a patient able to flex at the elbow, it is a KLUMPKE PALSY.
• ERBS PALSY (AKA ERB’S PALSY): Brachial plexus injury at C5-7 resulting in paralysis of the UPPER ARM. There is a “waiter’s tip” configuration and UNILATERAL DIAPHRAGMATIC PARALYSIS.
  
  • PEARLS: The grasp and extension of the hand are INTACT. Respiratory distress can result due to phrenic nerve injury (look for a broken clavicle) resulting in unilateral diaphragmatic paralysis. Often associated with LGA babies, breech deliveries and C-sections.
• KLUMPKE PALSY: Brachial plexus injury, but lower (C7-T1). This affects the LOWER arm and hand. Worse prognosis because the nerves are typically torn. Results in a CLAW HAND deformity in which there is an INABILITY TO GRASP.

Question 4

Infants born to diabetic mothers are at higher risk for all of the following EXCEPT:

a. Hyperbilirubinemia
b. Hypertrophic cardiomyopathy
c. Hypoplastic left colon
d. Sepsis

Answer 4

The answer is D, “Sepsis”

For the ABP exam, an infant of a diabetic mother (IDM) is at higher risk for congenital heart disease, congenital heart disease and CHD! Patients are especially prone to having septal defects. May also have coarctation of the aorta, hypertrophic obstructive cardiomyopathy (HOCM), truncus arteriosus, dextrocardia and more. Can also have rib or vertebral column abnormalities, hydrocephalus, macrosomia/LGA size (with birth trauma), small left colon, duodenal atresia (double bubble… or “gaseous distention in both the stomach and duodenum”), apnea, hypOcalcemia, hypOmagnesemia, hypOphosphatemia, hyperbilirubinemia, polycythemia, vascular thromboses and RDS (look for tachypnea). Surprisingly, sepsis is not more common in an IDM.

• PEARL: The hypoglycemia may not occur until ONE or TWO days after birth.
• PEARL: For hypocalcemia, look for jitteriness, a prolonged QT, Chvostek’s sign (tapping the facial nerve elicits a twitch) or Trousseau’s sign (carpopedal spasm noted when the wrist is clasped).

Question 5

A 10-year old girl presents with a painful lump on her neck. She says the pain started about a week ago. On exam, you note a tender cervical lymph node that measures approximately 2.5 cm. She has no fever and the lesion is not draining. She has a cat at home but denies ever being scratched. What is the next best step in management for the above patient?

a. Incision and drainage
b. Obtain a biopsy and send for pathology and culture
c. Treat with amoxicillin-clavulanate
d. Place a PPD
e. Watchful waiting with follow-up in 7 days

Answer 5

The answer is C, “Treat with amoxicillin-clavulanate”

This is ACUTE and TENDER lymphadenopathy (< 3 weeks) in the neck area. Bartonella and atypical mycobacteria tend to cause CHRONIC lymphadenopathy. STREPTOCOCCUS PYOGENES (AKA GAS or STREP PYOGENES) is your most likely culprit. Next in line is Staph aureus, especially if it’s in a neonate, or if it’s an acute lymphadenopathy associated with drainage of purulent material. Know the difference between the different types of Streptococcal species, as well as the different presentations for Staph versus Strep. You should also be familiar with the differential diagnosis of tender versus non-tender lymphadenopathy. Here is an excerpt from the core study guide on the differential for acute lymphadenopathy (refer to the study guide for more in depth discussion):

• STAPH: Look for cervical or submandibular lymphadenopathy in a neonate or infant. May also present as a breast abscess.
  
  • PEARLS: This is one of the few circumstances in which you would choose Staph as the correct answer if presented with a neonate. Also, while GBS is a common answer for neonates, GROUP A STREP (AKA GAS or Strep pyogenes) is probably NEVER the answer for a neonate.
• GROUP A STREP (GAS or STREP PYOGENES): Look for an older child with impetigo, pharyngitis or even a single inflamed lymph node.
• PREAURICULAR LYMPHADENOPATHY: Consider adenovirus if you see a patient with conjunctivitis. Mononucleosis may present with acute or chronic lymphadenopathy.
• EMPIRIC TREATMENT: Aim to cover beta-lactamase producers. AMOXICILLIN-CLAVULANATE! Other appropriate options include cefazolin, clindamycin and erythromycin.

Question 6

A 16-year old girl presents to your office. She has never had a menstrual cycle. On physical exam she has stage 5 breasts and no pubic hair. Her BMI is 22. What is the next best diagnostic test?

a. Electrolyte panel
b. Karyotype
c. Luteinizing hormone
d. Testosterone level

Answer 6

The answer is B, “Karyotype”

A karyotype will show that the patient has an XY genotype. The child was supposed to be a male, but due to defective androgen receptors, the “default” phenotype was created. Androgens are required for pubic hair, which is why this patent has none. Luteinizing hormone is a good screening test for PCOS.

Question 7

A 4-month old female is brought to an urgent care center. The mother is concerned about possible bleeding and is worried about a pink spot in the diaper. She brought the diaper to the visit, and upon inspection you clearly note a salmon-colored spot in the diaper. On physical examination, the child is healthy-appearing. Conjunctivae are pink. There is no blood noted at the vaginal introitus. Growth parameters are all at the 50th percentile, the child has a healthy appetite and breastfeeds well. A urine dip-stick shows no blood. What is the likely etiology?

a. Vaginal spotting
b. Nephrolithiasis
c. Oxalate crystals
d. Urate crystals

Answer 7

The Answer is D, “Urate crystals”

URIC ACID CRYSTALS: Seen in breast-fed babies and is harmless! It can also be associated with rapid cell turnover and hyperuricemia (as seen in lymphomas).

• PEARL: Look for a breast fed baby presenting with a pink spot in the diaper! Uric acid turns to a salmon or pink colored powder when it dries. It scares parents to heck, but only requires reassurance.

Question 8

What type of hearing screen is recommended in a 4-month old child?

a. Automated auditory brainstem response
b. Otoacoustic emissions
c. Visual reinforced audiometry
d. Pure tone audiometry

Answer 8

The answer is A, “Automated auditory brainstem response”

AUTOMATED AUDITORY BRAINSTEM RESPONSE: Measures brainstem response to sounds. This is better than the OAE test. It can check for unilateral, bilateral, conductive and/or sensory hearing loss. The infant should be sleeping for best results, therefore it is difficult to administer in children > 6-months of age.

Question 9

On DOL 3, a child is noted to have jaundice and a total bilirubin of 10. The baby is formula feeding well. The mother received appropriate prenatal care and workup for Rh disease and ABO incompatibility is negative. What is the next best step in management?

a. Discharge with follow-up in 48 hours
b. Start phototherapy
c. Start IV fluids
d. Prepare for plasma exchange

Answer 9

The answer is A, “Discharge with follow-up in 48 hours”

This child has PHYSIOLOGIC JAUNDICE. Physiologic jaundice is a diagnosis of exclusion. Look for a healthy infant with jaundice on DOL 2 through 5 with no pathologic explanation. Make sure somewhat of a workup has been done.

• PEARLS: KNOW AS MUCH AS YOU CAN ABOUT JAUNDICE AND HYPERBILIRUBINEMIA. The placenta clears unconjugated bilirubin in utero. The enzyme needed to conjugate the unconjugated (indirect) bilirubin to conjugated (direct) bilirubin can take some time to mature after birth. Jaundice within the first 24 hours should be investigated further with a direct and indirect bilirubin level. DIRECT hyperbilirubinemia in the newborn is ALWAYS BAD, and means there is serious pathology (likely a biliary obstruction). Any direct bilirubinemia > 1 is abnormal.DO NOT order phototherapy in a baby with direct hyperbilirubinemia because it can cause “bronze baby syndrome. ”Indirect hyperbilirubinemia could mean one of many disorders, including hemolysis (consider G6PD if male), prematurity, hypothyroidism, a genetic defect/enzyme deficiency (galactosemia, Crigler Najjar), sepsis or certain congenital TORCH infection. In an older child with a mild indirect bilirubinemia during an illness, it could also mean Gilbert syndrome (very benign).
• PEARL: Use of alcohol, heroin, phenobarbital, phenytoin and tobacco are all associated with a DECREASED risk of hyperbilirubinemia.

Question 10

A 40-year-old pregnant woman has a previous child with Down syndrome. She is now 15 weeks pregnant. What is the most appropriate recommendation for her?

a. No special testing
b. Maternal triple screen including HCG subunit
c. Amniocentesis
d. Chorionic villus sampling

Answer 10

The answer is C, “amniocentesis”

She is considered high risk for having another Trisomy 21 child (Down Syndrome = Trisomy 21) for multiple reasons (age + history of prior DS baby). It’s a good idea to be familiar with date cutoffs for the different trimesters (2^nd begins with the 13^th week, 3^rd begins with the 29^th week), and the different tests that can be offered for DS screening in first and second trimesters.

a. AMNIOCENTESIS: Generally considered a 2^nd trimester option. This is usually offered as a screen at 15-18 weeks for women over the age of 35. It can be offered earlier, at 12 weeks, in certain circumstances. For high-risk women, this is the preferred test since it is more sensitive and specific than serum testing. It is also less risky than CVS.
b. CHORIONIC VILLUS TESTING: Generally considered a 2^nd trimester option, but this can also be done as early as 12 weeks. It is more definitive but carries more risks, including an increased chance of miscarriage, when compared to amniocentesis.
c. MATERNAL SERUM TRIPLE OR QUADRUPLE SCREEN: Considered to be 2^nd trimester options. These include obtaining 3-4 of the serum markers noted below.

• AFP: Low is bad.
• Unconjugated estriol: Low is bad
• Beta HCG subunit: High is bad
• Inhibin (for the quadruple screen): High is bad

d. FIRST TRIMESTER OPTION: The usual first trimester option includes using a combination of ultrasound and serum HCG subunit testing late in the first trimester. The ultrasound is done to look for nuchal translucency. If that is found along with an elevated beta HCG, there’s a high chance of the baby having Down Syndrome.

Question 11

A crying 3-year old child is shown with macroglossia. The child seems to have microcephaly and has a history of an umbilical hernia. What’s the most likely diagnosis?

a. Hypothyroidism
b. Down Syndrome
c. Pierre-Robin Syndrome
d. Beckwith-Wiedemann Syndrome

Answer 11

The answer is D, “Beckwith-Wiedemann Syndrome”

BECKWITH-WIEDEMANN: Look for MACROglossia, MICROcephaly, MACROsomia (large body), midline abdominal wall defects and evidence of hemihypertrophy (AKA hemihyperplasia). The midline defect may be an omphalocele (bowel through the umbilicus) or umbilical hernia. Babies will often have neonatal hypoglycemia. Children are at increased risk for malignancies, especially Wilms Tumor. Look for a picture of a patient with a big body, big tongue and some type of overgrowth symptom (unilateral overgrowth of a leg, face, arm, etc.).

• PEARL: It’s the most common overgrowth syndrome in infancy.

Question 12

A male newborn had oligohydramnios noted on prenatal ultrasound. You examine the child a few hours after the delivery and are unable to palpate testicles in the scrotum. The child has not produced urine yet, and you note a very soft abdomen with a midline abdominal mass. Which of the following is the most likely diagnosis?

a. Congenital adrenal hyperplasia
b. Prune Belly Syndrome
c. Wilms Tumor
d. Kallmann Syndrome

Answer 12

The answer is B, “Prune Belly Syndrome”

The patient has PRUNE BELLY SYNDROME. This should be considered in any child with urinary tract abnormalities and cryptorchidism (absent testicles in the scrotum) or undescended testicles. Look for the other cardinal sign of weak abdominal musculature due to deficient abdominal muscles. The urinary tract anomalies include vesicoureteral reflux (VUR), posterior urethral valves (PUV) and renal dysplasia. The renal anomalies often result in hydronephrosis, oligohydramnios and pulmonary hypoplasia. Children have a poor prognosis and many unfortunately die within a few months.

• PEARL: Look for a newborn with weak abdominal muscles, “undescended testes” (may actually be missing) and a midline abdominal mass (distended bladder or hydronephrosis).

Question 13

A premature baby needs:

a. More sodium than a full-term neonate. Sodium supplementation should be started immediately.
b. More sodium than a full-term neonate. Sodium supplementation can be started after 24 hours.
c. Less sodium than a full term baby.
d. The same amount of sodium as a full-term baby.

Answer 13

The answer is B “More sodium than a full-term neonate. Sodium supplementation can be started after 24 hours.”

Premature babies have an increased fractional excretion of sodium (FE_Na) due to poor sodium reabsorption. The GFR and the sodium reabsorption improves with age. Sodium supplementation is not needed in the first 24-72 hours. Assume this is due to the initial water losses.

• PEARL: In VLBW babies, water losses can exceed sodium losses. This can actually result in hypernatremia if enough free water is not provided.

Question 14

A 4-year old child presents with a history of developmental delay. There has been concern that he may have autism. On exam you note that he has very light-colored skin, light-colored hair and a rash that appears eczematous. The mother says that he also tends to have “body odor.” You note a musty or “mousy” odor. You send off a panel of labs and note that his glucose, ammonia, anion gap and lactic acid levels are all essentially normal. What’s the diagnosis?

a. Alkaptonuria
b. Maple Syrup Urine Disease (MSUD)
c. Homocysteinuria
d. Phenylketonuria

Answer 14

The answer is D, “Phenylketonuria”

Aminoacidopathies are disorders in which isolated amino acids cannot be broken down. Since the problem is limited to only a particular amino acid, there is no significant elevation in ammonia levels (the exception is maple syrup urine disease, MSUD). Also, there is no acidosis because this is not a fuel issue (carbohydrate and fat metabolism are working fine, but once again MSUD is the exception). The amino acid disorders include phenylketonuria (PKU), alkaptonuria, MSUD, homocysteinuria and tyrosinemia.

Question 15

A 16-year old girl presents to your office. She has never had a menstrual cycle. On physical exam she has stage 5 breasts and no pubic hair. Her BMI is 22. What’s the diagnosis?

a. Anorexia induced amenorrhea
b. Turner Syndrome
c. Androgen insensitivity
d. Delayed puberty

Answer 15

The answer is C, “Androgen insensitivity”

It’s NOT A GIRL! Primary amenorrhea + breasts + lack of pubic hair = androgen insensitivity (AKA testicular feminization)!

• PEARL: Making the association between ANDROGENS and PUBIC hair is extremely important and very high yield.

Question 16

A baby girl is born at home in a tub. She was given a dose of oral vitamin K and is being breastfed. On DOL 3, the child starts to have sudden bleeding noted in her diaper. What’s the most likely diagnosis?

a. Factor VIII Deficiency
b. Factor IX Deficiency
c. Factor X Deficiency
d. Hemorrhagic Disease of the Newborn

Answer 16

The answer is D, “Hemorrhagic Disease of the Newborn”

For Hemophilia A, Hemophilia B and Factor X deficiency, look for bleeding due to minor trauma. Factor X deficiency can have mild spontaneous bleeding. VITAMIN K DEFICIENCY (AKA PHYTONADIONE DEFICIENCY) can result in HEMORRHAGIC DISEASE OF THE NEWBORN due to a coagulopathy. Not much Vitamin K crosses the placenta. Vitamin K is needed for use with coagulation factors 2, 7, 9, & 10. This is especially a concern in babies because there is a lack of normal gut flora needed to make the Vitamin K. Deficiency is also more common in breastfed babies (less Vitamin K in breast milk) who did not receive Vitamin K at birth. Look for a bleeding circumcision site, umbilical cord site or GI bleeding.

• PEARL: ORAL Vitamin K is not as effective at preventing HEMORRHAGIC DISEASE OF THE NEWBORN as the injection. It can help, but would need to be given in multiple doses. Also a mother being on warfarin or an anti-seizure medication can also increase the chances of Vitamin K deficiency.
• EARLY VITAMIN K DEFICIENCY: Occurs within 3 days.
• LATE VITAMIN K DEFICIENCY: Can occur any time between 3 days and 3 months! Look for a breastfed baby on antibiotics and having diarrhea (decreased gut flora to make Vitamin K due to antibiotic use, and decreased absorption due to diarrhea).
• TREATMENT: For bleeding patients, give Vitamin K + FFP (fresh frozen plasma contains plenty of functional Vitamin K dependent coagulation factors).

Question 17

A new rapid flu test has been released. You perform a study to compare results of the rapid test to those of influenza PCR testing. 120 patients were tested. 90 patients were confirmed to have the flu using PCR. Of those 90 patients, only 80 patients tested positive using the rapid test. Of the 30 patients confirmed by PCR to be negative for influenza, 5 patients tested positive by the new rapid test. What is the SENSITIVITY of the new rapid test?

a. 71%
b. 83%
c. 89%
d. 94%

Answer 17

The answer is C, “89%”

SENSITIVITY = TP/(TP+FN).

A high sensitivity [TP/(TP+FN)] is needed for SCREENING tests in order to rule out the presence of disease in a healthy patient. These are tests that are being done to RULE OUT a disease. So, a screening test should have a high sensitivity, which will mean that a negative result rules out the disease in that patient.

• MNEMONIC: spIN & snOUT. snOUT should remind you thatSeNsitivity (SNout) is related to ruling OUT a disease.

Question 18

An LGA baby is noted to have a firm, freely mobile, erythematous and nodular mass with distinct borders at the upper cheek on DOL 13. This is likely:

a. Fat necrosis of the newborn.
b. A lipoma
c. A sarcoma
d. Related to child abuse.

Answer 18

The answer is A “Fat necrosis of the newborn”

is a condition of unknown etiology. LGA status is a definite risk factor. Also, any child with a perinatal event (meconium aspiration, trauma, asphyxia, etc.) is at increased risk. It’s self-limited, but can be complicated by hypercalcemia that can be life-threatening. Look for a nodular lesion at the cheeks, thighs, buttocks or arms. No treatment, but do check electrolytes including calcium.

• PEARL: Cold exposure is another risk factor and the same findings could be referred to as a cold induced panniculitis. Look for a child with a pacifier filled with cold water. S/he will be afebrile.

Question 19

A healthy-appearing child is born to a mother that had poor prenatal care. Late in her pregnancy, she was found to have syphilis that was confirmed with a positive FTA. She was treated with erythromycin 6 weeks prior to the delivery. Non-treponemal titers are obtained from both the mother and the neonate. Both are positive. What’s the next best step in management?

a. Treat the mother and the baby with penicillin.
b. Treat the mother with penicillin and check the FTA in the baby.
c. Do not treat the mother. Treat the baby with penicillin.
d. Recheck the baby’s non-treponemal titers in one month.

Answer 19

The answer is B, “Treat the mother with penicillin and check the FTA in the baby.”

SYPHILIS: Caused by TREPONEMA PALLIDUM. Non-treponemal tests (+RPR or VDRL) can be FALSE positives so you need to do a confirmatory treponemal test (FTA). If a mom was RPR+ but the FTA was not done, obtain the FTA in the baby. FTA doesn’t correlate with disease activity, the non-treponemal tests do, and they may eventually disappear. So once disease presence is confirmed with FTA, look at disease activity with non-treponemal titers to help guide management. If mom was treated and the baby’s titers are lower than hers, it’s safe to assume those are just the mom’s IgGs that crossed placenta. There is NO NEED TO TREAT, just follow the titers. If mom was treated < 1 month ago, TREAT. If mom was given ERYTHROMYCIN, TREAT the baby because it doesn’t cross the placenta. Penicillin is the best treatment for syphilis and WILL cross the placenta and will therefore treat both MOM and BABY.

• CONGENITAL SYPHILIS: Baby born with maculopapular rash, HSM, PEELING SKIN, PERFORATED NASAL SEPTUM or HUTCHINSON TEETH. These teeth are peg-shaped (cone-like) teeth but also have a central notch that is extremely specific for congenital syphilis. Treat with PENICILLIN.
• CONDYLOMA LATA: Refers to SECONDARY SYPHILIS, in which white-gray coalescing papules are seen.
• PEARLS: If the FTA is positive but VDRL is negative, also consider LYME DISEASE (BORRELIA BURGDORFERI).

Question 20

Which abnormality is common in the recipient of a packed red blood cell (PRBC) transfusion and also in the recipient twin of a twin-to-twin transfusion?

a. Hyponatremia
b. Hypokalemia
c. Hypocalcemia
d. Hypophosphatemia

Answer 20

The answer is C “Hypocalcemia”

is a common transfusion related reaction, both in twin-to-twin transfusions and in regular PRBC transfusions. Hyperkalemia and thrombocytopenia are also common in regular PRBC transfusions. Consider using the mnemonics below to remember these findings.

• MNEMONICS: A usual PRBC transfusion is 10-20 cc/kg. Think of it as a giving a “bolus” of PRBCs (a “bolus” of IVF is 20 cc/kg). Regarding complications, think of calcium precipitating out as the 2 different bloods mix (actually it’s a citrate toxicity). For the hyperkalemia, imagine RBCs hemolyzing as they get sheared through the IV. For thrombocytopenia, just assume it’s a hemodilutional effect!

Question 21

You are shown an image of a newborn. He has what looks like a thin, transparent film on his body. Eyelashes are missing and eyelids seem inverted. What is the diagnosis?

a. Lamellar ichthyosis
b. Harlequin ichthyosis
c. Lichen striatus
d. Ichthyosis vulgaris

Answer 21

The answer is A, “Lamellar ichthyosis”

This is a classic description and image of lamellar ichthyosis. Of the choices, it should only be confused with harlequin ichthyosis, which also presents at birth, but is more severe. Harlequin ichthyosis is described as presenting with a hard and horny (“armor-like”) covering. Prognosis is comparatively poor

Question 22

A 10-year old girl presents with a painful lump on her neck. She says the pain started about a week ago. On exam, you note a tender cervical lymph node that measures approximately 2.5 cm. She has no fever and the lesion is not draining. She has a cat at home but denies ever being scratched. What is the most likely etiology?

a. Staphylococcus aureus
b. Streptococcus pyogenes
c. Streptococcus pneumoniae
d. Bartonella henselae
e. Atypical mycobacteria

Answer 22

The answer is B, “Streptococcus pyogenes”

This is ACUTE and TENDER lymphadenopathy (< 3 weeks) in the neck area. Bartonella and atypical mycobacteria tend to cause CHRONIC lymphadenopathy. STREPTOCOCCUS PYOGENES (AKA GAS or STREP PYOGENES) is your most likely culprit. Next in line is Staph aureus, especially if it’s in a neonate, or if it’s an acute lymphadenopathy associated with drainage of purulent material. Know the difference between the different types of Streptococcal species, as well as the different presentations for Staph versus Strep. You should also be familiar with the differential diagnosis of tender versus non-tender lymphadenopathy. Here is an excerpt from the core study guide on the differential for acute lymphadenopathy (refer to the study guide for more in depth discussion):

• STAPH: Look for cervical or submandibular lymphadenopathy in a neonate or infant. May also present as a breast abscess.
  
  • PEARLS: This is one of the few circumstances in which you would choose Staph as the correct answer if presented with a neonate. Also, while GBS is a common answer for neonates, GROUP A STREP (AKA GAS or Strep pyogenes) is probably NEVER the answer for a neonate.
• GROUP A STREP (GAS or STREP PYOGENES): Look for an older child with impetigo, pharyngitis or even a single inflamed lymph node.
• PREAURICULAR LYMPHADENOPATHY: Consider adenovirus if you see a patient with conjunctivitis. Mononucleosis may present with acute or chronic lymphadenopathy.
• EMPIRIC TREATMENT: Aim to cover beta-lactamase producers. AMOXICILLIN-CLAVULANATE! Other appropriate options include cefazolin, clindamycin and erythromycin.

Question 23

Which of the following congenital infections is associated with nasal perforation?

a. Toxoplasmosis
b. Rubella
c. Cytomegalovirus
d. Herpes simplex
e. Syphilis

Answer 23

The answer is E, “Syphilis”

Syphilis is associated with a maculopapular rash, hepatosplenomegaly, PEELING SKIN, PERFORATED NASAL SEPTUM and HUTCHINSON TEETH.

Question 24

A 4-month old child present due to morning irritability. He has not had a feeding in 5 hours and is again quite irritable. A glucometer reading shows a glucose level of 46. You send stat labs and ask the mother to start feeding the child. Lactic acid level is elevated, ammonia level is normal and the anion gap is 16. Which of the following does the child have?

a. Glycogen Storage Disease Type I (AKA von Gierke disease)
b. Glycogen Storage Disease Type II (AKA Pompe disease)
c. Niemann-Pick Disease
d. Isovaleric Acidemia

Answer 24

The answer is A, “Glycogen Storage Disease Type I (AKA von Gierke disease)”

GSD I is due to the inability use glycogen due to problems metabolizing glucose 6-phosphate (G6P). While patients can metabolize glucose itself and can break down glycogen, they are unable convert to glucose the G6P produced from glycogen or gluconeogenesis. During fasting, there is hypoglycemia plus the buildup of glycogen, lactic acid and lipids as G6P is shunted to different reactions. Glycogen can build up in organs and cause organomegaly. The main treatment is to provide a constant source of glucose by giving starch.

• PEARL: GSD I may present in babies when meals/feedings are starting to be spaced out. Also, for any patient presenting with morning issues, consider hypoglycemia as a possible reason.

In GSD II (Pompe disease, lysosomal acid maltase deficiency), glycogen cannot be broken down in lysosomes, so accumulates in cells. It is a LYsosomal storage disorder that often results in a large PUMP (heart), hence the mnemonics “PUMP-E’s” and pompLay (lysosomal).

Niemann-Pick Disease is a sphingomyelinase deficiency that results in neurologic issues.

Question 25

A child presents with a history of mild mental retardation and hypercalcemia. On exam he is quite talkative, has a smooth philtrum, a broad nasal bridge, an elf-like face and a murmur. What’s the most likely diagnosis?

a. Fetal Alcohol Syndrome
b. Williams Syndrome
c. Down Syndrome
d. Congenital Hyperparathyroidism

Answer 25

The answer is B, “Williams Syndrome”

Though patients usually have mild mental retardation, they also tend to have relatively high verbal skills and a fun, “cocktail party” personality, so they get along great with other people. Facial features include an elf-like face (“ELFIN” FACE), a low and flat nasal bridge, an upturned nose, a smooth philtrum and wide-spaced teeth. Other problems include SUPRAvalvular aortic stenosis (not involving the valve, but the aorta itself), peripheral pulmonic stenosis and hypercalcemia. Then can occasionally also have hypothyroidism.

• PEARL: If you see the word SUPRAvalvular stenosis, have a HIGH suspicion for this diagnosis.

Question 26

Patients with Alagille Syndrome are most likely to have problems with which of the following organ systems:

a. Hepatic
b. Neurologic
c. Renal
d. Respiratory

Answer 26

The answer is A, “Hepatic”

ALAGILLE SYNDROME (AKA ARTERIOHEPATIC DYSPLASIA) is a genetic disorder in which jaundice is noted in the newborn period. Look for a child with LIVER and HEART disease. Here are some associations: paucity of bile ducts (AKA intrahepatic biliary atresia or hypoplastic biliary ducts), pulmonary stenosis, a triangular face (underdeveloped mandible), hypercholesterolemia with xanthomas, eye abnormalities and acholic stools.

Question 27

A child has a history of Tetralogy of Fallot is noted to have a Tet spell. He looks fairly cyanotic on exam. All of the following medications can be given during an acute Tet spell EXCEPT:

a. Morphine
b. Phenobarbital
c. Phenylephrine
d. Metoprolol

Answer 27

The answer is B, “Phenobarbital”

Tet spells can result in cyanosis or even syncope and collapse as there is insufficient blood return to the pulmonary vasculature due to increased right to left shunting. First, a child should squat in order to increase blood return to the pulmonary artery. In younger children, the knees should be brought up to their chests. If that doesn’t work and the child ends up in the ER, morphine is usually the first-line agent. If that doesn’t work, then IV beta blockers or vasopressors may be used. IVF may also be given. Neither calcium channel blockers nor phenobarbital have a role in Tet spells.

Question 28

A neonate develops declining oxygen saturations on DOL 1. Capillary refill is slow and central cyanosis is noted. A chest X-ray is shown. You note clear lung fields. Which medication do you give next?

a. Furosemide
b. Prostacyclin

Answer 28

The answer is B, “Prostacyclin”

Treatment of cardiac disease in a neonate or infant can be challenging. Focus on a few key findings to look for, including age, presence of cyanosis, and chest X-ray findings. Hopefully, you will be given enough information to mentally diagnose a condition and provide management accordingly. If not, use the following rules to help guide you:

a. CYANOSIS IN A NEONATE < 7 DAYS OLD: Give PROSTAGLANDIN or PROSTACYCLIN. For your purposes, the two are synonymous. The quickest way to get blood to the lungs for oxygenation is by maintaining the ductus arteriosus. The high pressure from the aorta will force blood into the pulmonary artery.
b. RESPIRATORY DISTRESS OR CYANOSIS WITH A CLEAR CHEST X-RAY: Give PROSTAGLANDIN or PROSTACYCLIN. A CLEAR chest X-ray (or one that looks “too clear”), suggests there is not enough blood getting to the lungs. Giving PGE will change that through the mechanism discussed above.
c. EVIDENCE OF PULMONARY EDEMA: Hopefully this will be seen in a patient after DOL 1. If so, give FUROSEMIDE or another diuretic. Fluffy infiltrates mean there is pulmonary congestion/edema. This can happen due to a septal defect, a PDA or other reasons. The point is, if a child is in a fluid overloaded situation, then help remove fluid with a diuretic.
d. NOTE: Please note that the above rules are meant to guide you when you’re not sure of a diagnosis, but have been able to recognize at least a few key findings.

Question 29

A child is born to a mother with a history of hyperparathyroidism. The child is predisposed to having which of the following:

a. Hypercalcemia
b. Hypocalcemia
c. Hypophosphatemia
d. None of the above.

Answer 29

The answer is B, ”Hypocalcemia”

HYPOCALCEMIA (Ca < 8.5, or ionized Ca <5): This is less common than hypercalcemia, but has much greater morbidity associated with it and is thus more heavily tested on the boards. Can range from minimal symptoms due to mild hypocalcemia from hyperventilation to HORRIBLE outcomes. Symptoms of hypocalcemia include: paresthesias, tetany, carpopedal spasm/tetany (also known as Trousseau’s sign), Chvostek’s sign (abnormal reaction/tetany of the facial nerve when tapped), Seizures that do not respond to benzodiazepines, laryngospasm (resulting in tachypnea; can look/sound like croup), prolonged QT.

EARLY HYPOCALCEMIA: Occurring within the first 3 days of life. Differential includes INFANT OF A DIABETIC MOTHER, MATERNAL HYPERPARATHYROIDISM, ASPHYXIA and IUGR

LATE HYPOCALCEMIA: Occurring after DOL 7. Much wider differential, including:

• HYPOMAGNESEMIA: Hypomagnesemia causes PTH resistance and decreased PTH secretion, which in turn cause hypocalcemia. May not respond to the calcium gluconate.
  
  • PEARLS: Magnesium sulfate infusion (for tocolysis or preeclampsia) can result in severe hypocalcemia and possible hypomagnesemia. The mechanism is complex/unknown. Treat with calcium gluconate, but keep in mind that patients may not respond as quickly as would normally be expected. So if you are given a vignette about a hypocalcemic baby not responding to calcium gluconate, consider magnesium tocolysis as the etiology.
• DIGEORGE SYNDROME (22Q11 DELETION): Parathyroid problems resulting in low calcium, velocardiofacial defects, etc.
• HYPOPARATHYROIDISM: low calcium, high phosphorus
• PSEUDOHYPOPARATHYROIDISM: Autosomal dominant disorder resulting in resistance to PTH. Therefore, serum PTH will be high but serum calcium will be low and phosphorus will be high! This is a “pseudo” disorder but the clinical effects are real. Look for short/stubby 4^th digits (fingers and/or toes), developmental delay, obesity, and moon facies.
• VITAMIN D DEFICIENCY: Decreased calcium absorption
• ALKALOSIS: Shifts ionized/active calcium to the protein-bound form.
• ETHYLENE GLYCOL POISONING: Calcium oxalate crystals (shaped like long beer cans, or needles) are found in the urine with ethylene glycol, so just assume that there is SOO much calcium lost in the urine during this process that it results in hypocalcemia! Remember, the calcium oxalate crystals that have the X on them are unrelated.
• RHABDOMYOLYSIS: Calcium deposition into the muscles results in intravascular hypocalcemia.
• RENAL FAILURE: Results in an inability to hydroxylate Vitamin D to 1,25 form.
• NEPHROTIC SYNDROME: There is low albumin, so the measured albumin-bound calcium level is also low. Check the ionized calcium level.

Question 30

A new rapid flu test has been released. You perform a study to compare results of the rapid test to those of influenza PCR testing. 120 patients were tested. 90 patients were confirmed to have the flu using PCR. Of those 90 patients, only 80 patients tested positive using the rapid test. Of the 30 patients confirmed by PCR to be negative for influenza, 5 patients tested positive by the new rapid test. What is the SPECIFICITY of the new rapid test?

a. 71%
b. 83%
c. 89%
d. 94%

Answer 30

The answer is B, “83%”

SPECIFICITY = TN/(TN+FP).

A high specificity [TN/(TN+FP)] is needed for CONFIRMATORY tests. These are tests that are done to RULE IN (AKA CONFIRM) a disease. So, a confirmatory test should have a high specificity, which will mean that a positive result rules in the disease in that patient.

• MNEMONIC: spIN&snOUT. spIN should remind you thatSPecificity (SPin) is related to ruling IN a disease.

Question 31

A child is born by a normal vaginal delivery. About 8 hours later he is noted to be tachypneic and pale. Labs show that he is anemic. The RBC morphology is normal under microscopy. What is the likely etiology of these finding?

a. Chronic intrauterine blood loss.
b. Acute blood loss at birth.
c. Congenital heart disease.
d. Congenital syphilis

Answer 31

The answer is B “Acute blood loss at birth.”

Only A and B should have been on your radar. The normal RBC morphology should have tipped you off to the acuity of the problem. For a chronic anemia, you would also expect a fairly stable patient.

Question 32

A pregnant woman is being evaluated at 32 weeks gestation. The fetus is noted to have frequent premature heart beat on the monitor. The baby is having anywhere from 6-10 premature beats per minute. They are usually individual, but up to 3 have been noted in succession. The woman drinks 1 cup of coffee per day. What’s the next step?

a. No workup is indicated
b. Obtain a fetal echocardiogram
c. Recommend cessation of all caffeine intake and recheck in one week
d. Do a urine toxicology screen on the mother

Answer 32

The answer is B, “Obtain a fetal echocardiogram.”

Premature beats in a fetus are not normal and warrant a workup for congenital heart disease. A fetal echocardiogram should be done as soon as possible. If congenital heart disease exists, then precautions will need to be in place at the time of delivery.

• PEARL: In an older child, 3-4 PVCs per minute are generally allowed. Six or more should be investigated further. Start with checking electrolytes and obtaining a 12-lead EKG.

Question 33

A newborn baby boy is noted to have a case of glanular hypospadias, in which the opening is displaced, but still on the glans. The family requests that the boy be circumcised. The next best step in management is to:

a. Move forward with a circumcision and then refer the patient to urology for a future correction.
b. Move forward with a circumcision. The child does qualify for surgical correction.
c. Refer to urology for surgical correction.
d. Obtain a karyotype.

Answer 33

The answer is C, “Refer to urology for surgical correction”

Most cases of hypospadias do require repair. There are several reasons for this, including cosmetic appearance, proper growth of penis, ability for a male to urinate while standing and self-esteem. A circumcision should be postponed in all children with hypospadias because the foreskin is often used during the repair.

Question 34

A 2-year old boy is brought to the ER. His patents entered his room last night and saw a bat. The child was sleeping quietly at the time. The parents tried to catch the bat, but it flew out of the window before they could do so. What is the next best step in management?

a. Provide rabies vaccination
b. Provide human rabies immunoglobulin (HRIG)
c. Provide both rabies vaccination and human rabies immunoglobulin (HRIG)
d. If a thorough physical exam reveals no bite marks, provide reassurance and discharge the patient.

Answer 34

The answer is C, “Provide both rabies vaccination and human rabies immunoglobulin (HRIG)”

RABIES is caused by a VIRAL infection transmitted through bites, scratches and contact with mucous membranes of infected animals, such as BATS, dogs, foxes, RACCOONS (most common in US), skunks, and WOODCHUCKS. If the history suggests a possible exposure (wild/aggressive animal), treat with standard wound care PLUS human rabies immunoglobulin (HRIG) PLUS the 5 vaccine doses. If the animal is a pet, observation of the patient and animal is allowed without giving HRIG.

• PEARL: Rabbits, rats and squirrels (rodents) are NOT associated with rabies.
• PEARL: For the boards, if the word “BAT” is mentioned (alive, escaped, whatever!), treat as an exposure!

Question 35

An infant is brought in for a well-child visit. She has been noted to cough with feeds, even more so since the introduction of solids. A barium swallow is shown with multiple images. What is the most likely diagnosis?

a. Achalasia
b. Tracheoesophageal fistula with a blind pouch
c. H-type tracheoesophageal fistula
d. Esophageal web
e. Reflux

Answer 35

The answer is D, “Esophageal web”

An ESOPHAGEAL WEB can cause reflux-like symptoms, esophageal impaction and chest pain. It results from the failure of the esophagus to re-canalize in utero. The web then acts as an obstruction to the passage of a food bolus. Liquids, however, pass through more easily. Treatment requires dilation of the esophageal web.

• TRACHEOESOPHAGEAL FISTULA: There are several types of tracheoesophageal fistulas. For the commonly tested H-type TE fistula, look for increased coughing with liquids as they seep through the fistula and enter the trachea. A TE fistula with a blind esophageal pouch is the most common type of TE fistula. More specifically, the upper part of the esophagus is a blind pouch, and the lower part connects with the trachea.
  
  • PEARL: H-type TE fistulas may be discovered after a newborn leaves the hospital. The other two will surely be found prior to discharge. Look for a blind pouch on a barium swallow, a history of polyhydramnios, symptoms consistent with VACTERL or an image showing a curled nasogastric tube. For an H-type fistula, you could be given a history that is consistent with the fistula and an image showing a nasogastric tube going all the way to the stomach.
• ACHALASIA: Associated with forceful vomiting.

Question 36

A 9-month old child presents for routine follow-up. The child is healthy-appearing. The mother gives the infant to you for your exam. During the exam, the infant seems anxious, begins to cry, then stops breathing, becomes unresponsive and has some jerking movements. The pulse is measured at approximately 70 beats per minute. What’s the best next step in management?

a. Activate EMS and begin CPR
b. Provide positive pressure ventilation
c. Provide oxygen by nasal cannula
d. Blow on the face
e. Observe

Answer 36

The answer is E, “Observe”

The child had a BREATH-HOLDING SPELL. These are most common between 6 to 18 months of age. Children have apneic episodes in response to pain, fear, anger, frustration or injury. Children can become unconscious or even have a seizure with a postictal period. EEG is always normal. No specific treatment is required except making sure that children don’t hurt themselves during a seizure. The two subtypes of breath holding spells include cyanotic breath holding (associated with anger, frustration, and cyanosis) and pallid breath holding (associated with fear, pain, injury and a pale or “pallid” appearance).

Question 37

A 5-month-old male presents for a well-child visit. The child’s brother had developmental dysplasia of the hip. The patient has no extra folds and both the Barlow and Ortolani maneuvers are negative. The mother asks if this child needs to have any special tests done. What is the next best step in management?

a. Ultrasound of the hips.
b. Hip X-rays.
c. Reassure the mother that this child has a normal exam, but recommend follow up with an orthopedist for further evaluation and risk stratification.
d. Inform the mother that her son has a normal exam and he does not need any imaging studies.

Answer 37

The answer is D, “Inform the mother that her son has a normal exam and he does not need any imaging studies.”

DEVELOPMENTAL DYSPLASIA OF THE HIP – Infants with developmental dysplasia of the hip (DDH) may be noted to have a leg-length discrepancy, extra creases at the thigh, “clunks” or “clicks” on exam. A majority of newborn “clunks” resolve by 2 weeks of age. So do NOT obtain any imaging at the time of birth. ALL patients with an unequivocal Barlow or Ortolani maneuver (meaning there’s no question in your mind on exam) should be referred to an orthopedist for evaluation. There is only one category of infants in which the American Academy of Pediatrics guidelines REQUIRES further imaging. It’s the category of girls with a breech presentation. There are two categories in which imaging, or referral to an orthopedist, seems strongly recommended. These include boys with a breech presentation and girls with a history of an affected first-degree relative. For the purposes of the exam, you should order imaging for any child that fits into one of these three categories or has a positive exam. Everyone else can be followed up with serial exams if the exam is negative. That means a BOY with a history of an affected first-degree relative is treated the same as a boy without a history of an affected first-degree relative. One equivocal exam is okay but if it is equivocal on repeat examination at 2 weeks, then refer to orthopedics or obtain imaging. For children under 4 months of age, ultrasound should be used. After 4 months of age, X hip-rays should be used. Treatment of DDH requires a Pavlik harness.

• PEARL: The guidelines seem to suggest that referral to an orthopedist is the preferred option when there is concern. On the exam this may not be an option since the ABP likes for YOU to make such decisions instead of leaning on consultants. In that case, you will need to decide on the modality of imaging. The age cut-off for ultrasounds is 4 months, NOT 6 months. NEVER image before 2 weeks of age. For a child with no clinical signs of DDH on exam but with a NEED for evaluation based on high risk factors, you can ultrasound at 6 weeks or obtain radiographs at 4 months of age. When it comes to the Barlow and Ortolani signs, if EITHER of them are positive, refer or send for imaging (after 2 weeks of age)! ALL children should be “screened” periodically at the well-child visits by EXAM! Meaning, if you’re asked if you should “screen” a child for DDH at the 2-month visit, the answer is always going to be YES. Lastly, if you encounter an asymptomatic child that was supposed to get imaging (e.g., breech girl) but never did, and the patient is now 5 or 6 months old, GET IMAGING even if the exam is normal!

Question 38

A neonate develops respiratory distress and pulse oximetry shows declining saturations. A chest X-ray is shown. You note diffuse, fluffy interstitial infiltrates. Which medication do you give next?

a. Furosemide
b. Prostaglandin

Answer 38

The answer is A, “Furosemide”

a. CYANOSIS IN A NEONATE < 7 DAYS OLD: Give PROSTAGLANDIN or PROSTACYCLIN. For your purposes, the two are synonymous. The quickest way to get blood to the lungs for oxygenation is by maintaining the ductus arteriosus. The high pressure from the aorta will force blood into the pulmonary artery.
b. RESPIRATORY DISTRESS OR CYANOSIS WITH A CLEAR CHEST X-RAY: Give PROSTAGLANDIN or PROSTACYCLIN. A CLEAR chest X-ray (or one that looks “too clear”), suggests there is not enough blood getting to the lungs. Giving PGE will change that through the mechanism discussed above.
c. EVIDENCE OF PULMONARY EDEMA: Hopefully this will be seen in a patient after DOL 1. If so, give FUROSEMIDE or another diuretic. Fluffy infiltrates mean there is pulmonary congestion/edema. This can happen due to a septal defect, a PDA or other reasons. The point is, if a child is in a fluid overloaded situation, then help remove fluid with a diuretic.
d. NOTE: Please note that the above rules are meant to guide you when you’re not sure of a diagnosis, but have been able to recognize at least a few key findings.

Question 39

A premie is born at 33 weeks in a taxi. In the ER, the baby is noted to have a temperature of 35 degrees Celsius. The child should be placed:

a. In a bassinette.
b. In an incubator at 40 degrees Celsius.
c. Under a radiant warmer at maximum temperature.
d. Under a radiant warmer at preferred skin temperature.

Answer 39

The answer is D “Under a radiant warmer at preferred skin temperature.”

The child is too hypothermic to put in a bassinette. Placing a premie in an incubator at 40 degrees Celsius, or under a radiant warmer at the maximum temperature would overheat the child. Also, the typical set point for an incubator is 36.5 – 37.4 degrees.

• PEARLS: Incubator temperatures can be difficult to control, so it’s good to have the baby under a warmer while work is being done in the ER. Otherwise, a great deal of warmth is lost when the door is opened. In general, radiant warmers tend to be associated with less morbidity. Check temperature frequently. Move the baby to a pre-warmed incubator once the door will not be opened frequently.

Question 40

A woman is in labor with a full-term child. She has one other child and states that he had a “Strep problem” after being born and needed IV antibiotics. She had a UTI 4 weeks ago and was given antibiotics. She had a GBS screen 3 weeks ago, which was negative. What is the next best step?

a. Send a stat GBS screen
b. Do nothing because GBS prophylaxis is not indicated.
c. Give GBS prophylaxis immediately.
d. Let her deliver by vaginal delivery and then monitor the child for 48 hours before allowing discharge.

Answer 40

The answer is C, “Give GBS prophylaxis immediately.”

GBS prophylaxis isindicated unless it was negative during this pregnancy at a time when the patient had not recently been on antibiotics. Here is your GBS screening & prophylaxis made easy!

• The screen occurs at 35-37 weeks. If indicated, give penicillin at least 4 hours prior to delivery.
• TO GIVE OR NOT TO GIVE?
  
  • Premature rupture of membranes (PROM) over 18 hours ago: YES
  • Prior PCN treatment during this pregnancy for a positive screen: YES. Don’t assume it cleared. You still have to give prophylaxis!
  • Previous infant with invasive GBS disease: YES
  • Intrapartum temperature > 100.4°F: YES
  • Prior GBS positivity in a previous pregnancy with a recent negative screen: NO
  • Status unknown and complicated pregnancy or premature (< 37 weeks): YES
  • Status unknown and uncomplicated pregnancy and term (> 37 weeks): NO
  • C-section with artificial rupture of membranes (AROM) with positive GBS screen: NO
• PEARL: If a child is born to a GBS positive mother, s/he should be watched in the hospital for at least 48 hours before being allowed to go home.

Question 41

A child is noted to have jaundice on DOL 1 at approximately 20 hours birth. There is a family history of physiologic jaundice. The child is being breastfed by his Rh+ mother. What is the most likely diagnosis?

a. Physiologic jaundice
b. Rhesus disease
c. Breast milk jaundice
d. TORCH Infection

Answer 41

The answer is D, “TORCH Infection”

Any time you see jaundice within the first 24 hours of life, that is BAD. Physiologic jaundice is a diagnosis of exclusion and usually occurs on DOL 3 or 2 at the earliest. Rh disease occurs in Rh- mothers. Breast milk jaundice usually occurs at about 1 week, though it can present earlier (this is not the same thing as breastfeeding jaundice). That only leaves the TORCH infections.

Question 42

A 4-year old child presents with a history of developmental delay. There has been concern that he may have autism. On exam you note that he has very light-colored skin, light-colored hair and a rash that appears eczematous. The mother says that he also tends to have “body odor.” You note a musty or “mousy” odor. You send off a panel of labs and note that his glucose, ammonia, anion gap and lactic acid levels are all essentially normal.

The patient is eventually diagnosed with an amino acid problem. What type of diet should be prescribed?

a. A diet high in carbohydrates and fats but low in protein
b. A diet that is low in the amino acid causing the problem
c. A diet with that contains none of the amino acid causing the problem
d. A diet that is high in carnitine

Answer 42

The answer is B, “A diet that is low in the amino acid causing the problem”

PHENYLKETONURIA (PKU) is a deficiency of phenylalanine hydroxylase. Phenylalanine can’t be broken down into tyrosine. If left untreated, patients will be asymptomatic for a few months. They can then start to present with developmental delay, a musty/mousy odor, skin/hair changes (LIGHT colored skin and hair; possibly eczema-like rash) and eventually might even carry a diagnosis of “autism” because of severe mental retardation. The disease is also associated with septal defects.

All states test for this on the newborn screen, which looks for an elevated phenylalanine level. Your first step in neonates should be to REPEAT the test because some kids have a TRANSIENT elevation in their phenylalanine level at birth. If it’s abnormal again, the child still might be ok because it may just be that the enzyme hasn’t matured yet. Consult a geneticist to sort it out. The goal should be to start treatment by 14 days of life, otherwise severe mental retardation can occur.

TYROSINE levels will be low or nonexistent in kids with PKU, so tyrosine becomes an essential amino acid. Some children require tyrosine supplementation in the diet. The general treatment, though, is a LOW PHENYLALANINE DIET. OVER-TREATING (meaning zero phenylalanine) can result in lethargy, rash and diarrhea (don’t get it confused with pellagra!). Also, if an affected pregnant mother has poor dietary control, her child can be born with microcephaly, congenital heart defects (CHD) and cognitive defects.

• PEARL: Look for a child that looks like they might have albinism. Also, keep in mind that the newborn screen is only valid AFTER protein intake.

Question 43

A newborn is noted to have a distended abdomen and bilious emesis. It has been 24 hours and meconium has not been passed. A contrast study shows contrast throughout the colon. Which of the following is the most likely diagnosis?

a. Malrotation
b. Duodenal atresia
c. Microcolon
d. Intussusception

Answer 43

The answer is C, “Microcolon”

The image shows what is clearly a barium enema with a small caliber colon (think colon). This child has megacystis microcolon intestinal hypoperistalsis syndrome. It usually occurs in females and is associated with constipation, meconium ileus and urinary retention. The key to answering the question is to know what a normal colon should look like on a contrast study. This one is too thin.

• PEARL: Hypoplastic left colon is a condition that has a strong association with maternal diabetes (IDDM). Look for a colon that is small from the splenic flexure to the anus

Question 44

A new rapid flu test has been released. You perform a study to compare results of the rapid test to those of influenza PCR testing. 120 patients were tested. 90 patients were confirmed to have the flu using PCR. Of those 90 patients, only 80 patients tested positive using the rapid test. Of the 30 patients confirmed by PCR to be negative for influenza, 5 patients tested positive by the new rapid test. What is the Positive Predictive Value of the new rapid test?

a. 71%
b. 83%
c. 89%
d. 94%

Answer 44

The answer is D,“94%”

POSITIVE PREDICTIVE VALUE = TP/(TP+FP).

• The positive predictive value [TP/(TP+FP)] looks at all of the POSITIVE results from a test and predicts how likely it is that a positive result actually means a patient has the disease. For example, what are the chances that a patient with a positive flu test actually has the flu? The positive predictive value of a test depends on how prevalent it is in the population being tested. Think about it: even given the same sensitivity and specificity, a positive test for influenza is more likely to indicate true disease than is a positive test for smallpox, since smallpox has a prevalence of zero.

NEGATIVE PREDICTIVE VALUE = TN/(TN+FN).

• The negative predictive value [TN/(TN+FN)] looks at all of the NEGATIVE results from a test and predicts how likely it is that a negative result actually means a patient does not have the disease. For example, what are the chances that a patient with a negative flu test in fact does not have the flu? As with PPV, NPV depends on prevalence, but inversely.

Question 45

A newborn is noted to have jaundice at 48 hours of life. Labs show a predominantly indirect hyperbilirubinemia with a total bilirubin level is 10. The child is formula feeding well. The child was born at 37 weeks gestation, has a brother who required phototherapy, and has a small cephalohematoma. What’s the next step in management?

a. No intervention is needed
b. Recheck bilirubin in 8 hours
c. Start phototherapy
d. Obtain a stat right upper quadrant ultrasound

Answer 45

The answer is A “No intervention is needed”

The child has high risk, but does not need phototherapy and may be discharged.

a. RISK FACTORS FOR DEVELOPING HYPERBILIRUBINEMIA: G6PD deficiency, asphyxia, temperature instability, sepsis, acidosis, albumin < 3, ABO incompatibility, Rh disease, sibling with history of phototherapy, bruising, cephalohematoma and exclusive breastfeeding that is not going well. SO ALMOST ANYTHING IS A RISK FACTOR. Focus instead on identifying neonates that are at high and medium risk of developing hyperbilirubinemia, as well as memorizing the bilirubin levels at which phototherapy should be initiated.
b. HIGHEST RISK BABIES: 35 – 37 + 6/7 weeks WITH risk factors
c. MEDIUM RISK BABIES: 35 – 37 + 6/7 weeks WITHOUT risk factors. OR, > 38 weeks WITH risk factors.
d. LOW RISK BABIES: >38 weeks and well
e. START PHOTOTHERAPY ON HIGH RISK NEONATES IF:

• TOTAL bilirubin >8 at 24 hours
• TOTAL bilirubin >11 at 48 hours
• TOTAL bilirubin >13 at 72 hours

f. SHORTCUTS FOR WHEN TO START PHOTOTHERAPY IN MEDIUM & LOW RISK NEONATES:

• MEDIUM risk: The bilirubin threshold increases by 2 (so approximately 10, 13, and 15).
• LOW risk: The bilirubin threshold increases by 4 (so approximately 12, 15 and 18).

g. PEARL: NONE OF THE ABOVE-MENTIONED RISK FACTORS AND BILIRUBIN THRESHOLDS APPLY TO PREMATURE NEONATES < 35 WEEKS.

Question 46

An 18-year-old teen gets pregnant after her first sexual encounter. She has an uncomplicated pregnancy and received adequate prenatal care. Soon after birth, the newborn is found to be jaundiced. The child is found to have a total bilirubin of 13. A blood smear shows spherocytes. The mother’s blood type is O, Rh-. The newborn’s blood type is A, Rh+. What is the most likely cause of the hyperbilirubinemia?

a. ABO incompatibility
b. Rhesus disease
c. Hereditary spherocytosis
d. Biliary atresia

Answer 46

The answer is A, “ABO incompatibility”

The child has hyperbilirubinemia, and multiple possible reasons for hemolysis. Not that this is a FIRST TIME pregnancy, which rules out Rhesus disease as a possible answer. Rh disease occurs during second pregnancies when immunoglobulins have formed against the Rh+ blood cells from a previous exposure. Also, ABO incompatibility tends to be associated with spherocytes, while Rh disease tends to be associated with nucleated RBCs (erythroblasts).

• PEARL: Hereditary spherocytosis can also result in hemolysis and jaundice, but you would have to be given “SPLENOMEGALY” as an exam finding.
• PEARL: If they refer to an RBC that does not have central pallor, they are referring to spherocytes.

Question 47

A newborn baby boy is noted to have small hands and hypotonia. Magnesium sulfate tocolysis was given to the mother. The child’s hypotonia is most likely due to:

a. Magnesium sulfate
b. Hypothyroidism
c. Prader Willi Syndrome
d. Achondroplasia

Answer 47

The answer is C, “Prader Willi Syndrome”

The rest can cause hypotonia, and achondroplasia can be associated with “trident-like” fingers, but not small hands.

Prader-Willi syndrome (AKA Prader Willi syndrome) patients can have hypotonia (floppy baby), mild retardation, almond-shaped eyes (often with mild strabismus), small hands, a HUGE appetite, obesity, and small testicles/penis in boys.

• PEARLS: Like Angelman’s, it can be found in BOYS or GIRLS. This mechanism of this disorder is the mirror image of that of Angelman’s. It occurs due to the absence or dysfunction of the PATERNAL copy of a gene in the same region of chromosome 15 as in Angelman syndrome. It also occurs when two maternal copies of chromosome 15 were received and no paternal copies (maternal disomy), and also when a mutation of the paternal gene makes it behave like the MATERNAL gene (called maternal imprinting). Symptoms are much milder in females. The gene location is probably not important for the test, but the fact that it is KNOWN (15q11-13) means that this disorder can be diagnosed by FISH.

Question 48

A child is born with choanal atresia, a cleft palate and syndactyly in his upper and lower extremities. He’s discharged from the hospital and is noted to have early suture closure over the coming months. Two images are shown. What disorder does the child have?

a. Smith-Lemli-Opitz
b. Crouzon Syndrome
c. Pierre-Robin Syndrome
d. Apert Syndrome

Answer 48

The answer is D, “Apert Syndrome”

Patients with Apert syndrome can have the 4 features mentioned (bilateral syndactyly, craniosynostosis, cleft palate and choanal atresia). Inheritance is autosomal dominant. Most cases are from sporadic mutations because of poor reproductive fitness. Crouzon has craniosynostosis, but NOT syndactyly. Smith-Lemli-Opitz syndrome has 2-3 syndactyly. Pierre-Robin syndrome can have syndactyly, but the other symptoms do not fit.

• PEARL: Craniosynostosis (early suture closure) + BILATERAL syndactyly = PICK APERT on the exam! Unilateral syndactyly is probably something else.

Question 49

A girl in college is brought to the ER. She is confused and hyperthermic. Her roommate states that she went to a party on the previous night. What is the likely etiology?

a. Heroin related reaction
b. Lysergic acid diethylamide (LSD)-related reaction
c. Ecstasy related reaction
d. Alcohol dehydrogenase deficiency

Answer 49

The answer is C, “Ecstasy related reaction”

The patient in the vignette has malignant hyperthermia. This is an inherited disorder that can result in fever, confusion, muscle contractions and even rhabdomyolysis after exposure to a trigger such as anesthesia or a stimulant drug. She was likely exposed to ecstasy (AKA methylenedioxymethamphetamine and MDMA) the previous night. Ecstasy use is also associated with seizures, coma and short-term memory loss.

Question 50

What type of hearing screen is recommended in a 6-year old child?

a. Automated auditory brainstem response
b. Otoacoustic emissions
c. Visual reinforced audiometry
d. Pure tone audiometry

Answer 50

The answer is D, “Pure tone audiometry”

SCREENING IN INFANTS < 6 MONTHS OLD: Use the ABR or OAE.

• AUTOMATED AUDITORY BRAINSTEM RESPONSE: Measures brainstem response to sounds. This is better than the OAE test. It can check for unilateral, bilateral, conductive and/or sensory hearing loss. The infant should be sleeping for best results, therefore it is difficult to administer in children > 6-months of age.
• OTOACOUSTIC EMISSIONS TESTING: This measures sounds that are made by the normally functioning cochlea in response to external sound. There is much more room for error in a noisy environment. Cost is similar, but false positives result in frequent audiology referrals. The infant should be sleeping for best results, therefore it is difficult to administer in children > 6-months of age.

SCREENING CHILDREN 6 MONTHS TO 2 YEARS OLD: For these preschoolers, use VISUAL REINFORCED AUDIOMETRY. This checks for bilateral hearing loss.

SCREENING CHILDREN OF SCHOOL AGE: Use PURE TONE AUDIOMETRY. At this age, children can wear headphones and let the examiner know which side the sound is coming from.