A 12-year-old boy is brought to the physician for a well-child examination. He feels well. He has no history of serious illness. He has received all age-appropriate screenings and immunizations. His 7-year-old brother was treated for nephrotic syndrome 1 year ago. He is at 50th percentile for height and 60th percentile for weight. His temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 96/54 mm Hg. Physical examination shows no abnormalities. Urine dipstick shows 1+ protein. A subsequent urinalysis of an early morning sample shows:
Blood negative
Glucose negative
Protein trace
Leukocyte esterase negative
Nitrite negative
RBC none
WBC 0–1/hpf
Protein/creatinine ratio 0.2 (N ≤ 0.2)
Which of the following is the most appropriate next step in management?
Q82
A 5-day-old male presents to the pediatrician for a well visit. The patient has been exclusively breastfed since birth. His mother reports that he feeds for 30 minutes every two hours. She also reports that she often feels that her breasts are not completely empty after each feeding, and she has started using a breast pump to extract the residual milk. She has been storing the extra breastmilk in the freezer for use later on. The patient urinates 6-8 times per day and stools 3-4 times per day. His mother describes his stools as dark yellow and loose. The patient was born at 41 weeks gestation via cesarean section for cervical incompetence. His birth weight was 3527 g (7 lb 12 oz, 64th percentile), and his current weight is 3315 (7 lb 5 oz, 40th percentile). His temperature is 97.3°F (36.3°C), blood pressure is 62/45 mmHg, pulse is 133/min, and respirations are 36/min. His eyes are anicteric, and his abdomen is soft and non-distended.
Which of the following is the best next step in management?
Q83
A 15-year-old boy is brought to the physician with excessive daytime sleepiness over the past year. His parents are concerned with his below-average school performance over the last 3 months. He goes to bed around midnight and wakes up at 7 am on school days, but sleeps in late on weekends. He exercises regularly after school. He usually has a light snack an hour before bed. He does not snore or have awakenings during sleep. He has no history of a serious illness and takes no medications. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. He does not smoke or drink alcohol. There is no history of a similar problem in the family. His vital signs are within normal limits. His BMI is 22 kg/m2. Physical examination shows no abnormal findings. Which of the following is the most appropriate recommendation at this time?
Q84
A 4-year-old girl presents to the office with her parents who are concerned about their daughter and slow, progressive changes in her behavior. The girl was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines and was meeting all developmental milestones until about 2 years ago. At one point she had a vocabulary of several words and now she verbalizes in grunts. She also flaps her hands in a repeated motion and has difficulty walking. Her parents have tried several home therapies to improve their daughter's symptoms including restricted diets, hydrotherapy, and a variety of nutritional supplements. The vital signs include: heart rate 90/min, respiratory rate 22/min, blood pressure 110/65 mm Hg, and temperature 36.9°C (98.4°F). On physical exam, she is well nourished and stares absently out the window. Her heart has a regular rate and rhythm and her lungs are clear to auscultation bilaterally. She has mild scoliosis. Which of the following is the most likely diagnosis?
Q85
A concerned mother presents to clinic stating that her 14-year-old son has not gone through his growth spurt. She states that, although shorter, he had been growing at the same rate as his peers until the past year. There is no evidence of delayed puberty in the mother, but the father's history is unknown. The patient has no complaints. On physical exam, the patient is a healthy-appearing 14-year-old boy whose height is below the third percentile and whose weight is at the 50th percentile. His bone age is determined to be 11 years. A laboratory workup, including thyroid stimulating hormone (TSH), is unremarkable. What is the most likely diagnosis?
Q86
An 8-year-old boy is brought to the hospital because of blurred vision and headache for 3 months. During this period, the father has noticed that the child has been tilting his head back to look straight ahead. The patient has also had difficulty falling asleep for 2 months. He has had a 3.5 kg (7.7 lb) weight loss over the past 6 months. His temperature is 37.7°C (99.8°F), pulse is 105/min, and blood pressure is 104/62 mm Hg. Examination shows equal pupils that are not reactive to light. The pupils constrict when an object is brought near the eye. His upward gaze is impaired; there is nystagmus and eyelid retraction while attempting to look upwards. Neurologic examination shows no other focal findings. Which of the following is the most likely sequela of this patient's condition?
Q87
An 18-month-old boy is brought to the physician by his mother because of concern that he has not yet begun to walk. He was born at term and exclusively breastfed until 15 months of age. His mother says he has been well, apart from an episode of high fever and seizure 4 months ago for which she did not seek medical attention. He has an older brother who is currently receiving medical treatment for failure to thrive. His parents have no history of serious illness; they are of normal height. His last vaccine was at the age of 4 months. He is at the 20th percentile for length, 10th percentile for weight, and 50th percentile for head circumference. Physical examination shows dry mucous membranes and erosion of the enamel on the lingual surface of the incisors and carious molars. He has frontal bossing. His wrists are widened, his legs seem bent, and there is beading of the ribs. Which of the following is the most likely underlying cause of this patient's delay in walking?
Q88
An 8-year-old boy presents to his pediatrician for a well visit. His parents state that he has been doing well in school and has many friends. The patient is a member of the chess club and enjoys playing video games. He has a past medical history of asthma which is treated with albuterol. The patient is in the 99th percentile for weight and 30th percentile for height. His temperature is 99.5°F (37.5°C), blood pressure is 122/88 mmHg, pulse is 90/min, respirations are 11/min, and oxygen saturation is 98% on room air. The patient's body mass index is 39.1 kg/m^2 at this visit. On physical exam, you note a young boy who maintains eye contact and is excited to be at the doctor's office. Cardiopulmonary exam is within normal limits. Abdominal exam reveals normal bowel sounds and is non-tender in all 4 quadrants. Neurological and musculoskeletal exams are within normal limits. Which of the following is the most likely outcome in this patient?
Q89
A 4-year-old boy is brought to the physician because of non-fluent speech. His mother worries that his vocabulary is limited for his age and because he cannot use simple sentences to communicate. She says he enjoys playing with his peers and parents, but he has always lagged behind in his speaking and communication. His speech is frequently not understood by strangers. He physically appears normal. His height and weight are within the normal range for his age. He responds to his name, makes eye contact, and enjoys the company of his mother. Which of the following is the most appropriate next step in management?
Q90
A previously healthy 6-month-old girl is brought to the physician by her mother for occasional “eye crossing.” Her mother says that the symptoms have become worse, especially before bedtime. The patient was born via cesarean delivery at 37-weeks' gestation and has met all developmental milestones. The patient's immunizations are up-to-date. She is at the 50th percentile for both length and weight. Her temperature is 36.7°C (98°F), pulse is 130/min, respirations are 40/min, and blood pressure is 90/60 mm Hg. Visual acuity is 20/20 in both eyes. There is an asymmetric corneal light reflection. When the left eye is covered, the right eye moves laterally. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in the management of this patient?
Growth/Development US Medical PG Practice Questions and MCQs
Question 81: A 12-year-old boy is brought to the physician for a well-child examination. He feels well. He has no history of serious illness. He has received all age-appropriate screenings and immunizations. His 7-year-old brother was treated for nephrotic syndrome 1 year ago. He is at 50th percentile for height and 60th percentile for weight. His temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 96/54 mm Hg. Physical examination shows no abnormalities. Urine dipstick shows 1+ protein. A subsequent urinalysis of an early morning sample shows:
Blood negative
Glucose negative
Protein trace
Leukocyte esterase negative
Nitrite negative
RBC none
WBC 0–1/hpf
Protein/creatinine ratio 0.2 (N ≤ 0.2)
Which of the following is the most appropriate next step in management?
A. Anti-nuclear antibody level
B. Repeat urine dipstick in 1 year (Correct Answer)
C. Measure serum creatinine and urea nitrogen
D. 24-hour urine protein collection
E. Lipid profile
Explanation: ***Repeat urine dipstick in 1 year***
- The initial 1+ protein on a random dipstick with a normal early morning protein/creatinine ratio (0.2, which is ≤0.2) is consistent with **benign orthostatic (postural) proteinuria** in an otherwise healthy adolescent.
- **Orthostatic proteinuria** is a common, benign finding in adolescents where protein appears in upright position but resolves when supine (hence the trace protein in early morning sample).
- Given the patient is asymptomatic, has normal vital signs, no edema, and a normal protein/creatinine ratio, this represents a benign condition requiring only monitoring with annual urine dipstick to ensure no progression.
- The family history of nephrotic syndrome in his brother does not change management in this asymptomatic patient with normal findings.
*Anti-nuclear antibody level*
- An **ANA level** is used to screen for **systemic lupus erythematosus** (SLE) and other autoimmune diseases that can cause glomerulonephritis.
- The patient has no symptoms or signs (e.g., rash, joint pain, serositis, hematuria) suggestive of an autoimmune condition, and the normal protein/creatinine ratio makes significant renal pathology unlikely.
*Measure serum creatinine and urea nitrogen*
- This would be appropriate if there was evidence of **renal dysfunction**, such as persistent abnormal proteinuria (protein/creatinine ratio >0.2), elevated blood pressure, or other signs of kidney disease.
- The patient has normal blood pressure, no edema, and a normal protein/creatinine ratio indicating no impaired kidney function.
*24-hour urine protein collection*
- A **24-hour urine collection** is indicated when there is sustained, significant proteinuria that needs quantification (e.g., to confirm nephrotic syndrome with >3.5 g/day or to monitor chronic kidney disease).
- The patient's normal protein/creatinine ratio (0.2) already provides adequate quantification and confirms the initial 1+ protein was transient orthostatic proteinuria, making 24-hour collection unnecessary.
*Lipid profile*
- A **lipid profile** is typically ordered in cases of suspected or confirmed **nephrotic syndrome**, as dyslipidemia is a common complication.
- This patient does not have nephrotic syndrome, which requires proteinuria >3.5 g/day (protein/creatinine ratio >3.5), hypoalbuminemia, edema, and hyperlipidemia—none of which are present.
Question 82: A 5-day-old male presents to the pediatrician for a well visit. The patient has been exclusively breastfed since birth. His mother reports that he feeds for 30 minutes every two hours. She also reports that she often feels that her breasts are not completely empty after each feeding, and she has started using a breast pump to extract the residual milk. She has been storing the extra breastmilk in the freezer for use later on. The patient urinates 6-8 times per day and stools 3-4 times per day. His mother describes his stools as dark yellow and loose. The patient was born at 41 weeks gestation via cesarean section for cervical incompetence. His birth weight was 3527 g (7 lb 12 oz, 64th percentile), and his current weight is 3315 (7 lb 5 oz, 40th percentile). His temperature is 97.3°F (36.3°C), blood pressure is 62/45 mmHg, pulse is 133/min, and respirations are 36/min. His eyes are anicteric, and his abdomen is soft and non-distended.
Which of the following is the best next step in management?
A. Continue current breastfeeding regimen (Correct Answer)
B. Increase frequency of breastfeeding
C. Supplement breastfeeding with conventional formula
D. Offer stored breastmilk between feedings
E. Modification of the mother’s diet
Explanation: ***Continue current breastfeeding regimen***
- The infant's **urination and stooling patterns** are appropriate for his age, indicating adequate hydration and milk intake.
- While the infant experienced a **physiologic weight loss**, his current weight is still within a healthy percentile, and he is showing signs of recovery.
*Increase frequency of breastfeeding*
- The infant is already feeding every two hours for 30 minutes, which is an **appropriate frequency and duration** for a 5-day-old.
- Increasing the frequency further without clear signs of inadequate intake could lead to **maternal fatigue** and an inability to sustain the regimen long-term.
*Supplement breastfeeding with conventional formula*
- Supplementation with formula is typically reserved for cases where there is **insufficient milk transfer or production**, significant weight loss, or dehydration.
- This infant's **normal voiding, stooling, and improving weight** do not indicate a need for formula supplementation at this time, which could interfere with establishing exclusive breastfeeding.
*Offer stored breastmilk between feedings*
- Offering stored breastmilk between feedings would effectively treat the stored milk as a **supplement**, which is not indicated given the current reassuring signs.
- Overfeeding could potentially lead to **gastrointestinal discomfort** or interfere with the infant's natural hunger cues and the establishment of an efficient breastfeeding relationship.
*Modification of the mother’s diet*
- A mother's diet rarely influences the **composition or quantity of breast milk** to an extent that would address concerns like inadequate infant weight gain in a healthy, full-term infant.
- There is no indication that the mother's diet is causing any issues with the infant's feeding or tolerance based on the provided information.
Question 83: A 15-year-old boy is brought to the physician with excessive daytime sleepiness over the past year. His parents are concerned with his below-average school performance over the last 3 months. He goes to bed around midnight and wakes up at 7 am on school days, but sleeps in late on weekends. He exercises regularly after school. He usually has a light snack an hour before bed. He does not snore or have awakenings during sleep. He has no history of a serious illness and takes no medications. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. He does not smoke or drink alcohol. There is no history of a similar problem in the family. His vital signs are within normal limits. His BMI is 22 kg/m2. Physical examination shows no abnormal findings. Which of the following is the most appropriate recommendation at this time?
A. Take melatonin before bedtime
B. Avoid snacks before bedtime
C. Decrease exercise intensity
D. Increase nighttime sleep hours (Correct Answer)
E. Take a nap in the afternoon
Explanation: ***Increase nighttime sleep hours***
- The patient's pattern of going to bed at midnight and waking at 7 AM on school days, along with sleeping in late on weekends, suggests a **chronic sleep deficit** accumulated during the week. Adolescents typically require 8-10 hours of sleep per night.
- The excessive daytime sleepiness and declining school performance are strong indicators of insufficient sleep, and **prioritizing more sleep during school nights** is the most direct intervention.
*Take melatonin before bedtime*
- Melatonin supplements are typically used for **sleep-onset insomnia** or **circadian rhythm disorders**, neither of which is clearly indicated here.
- There is no evidence presented of difficulty falling asleep; rather, the issue appears to be insufficient duration of sleep due to **late bedtime schedules**.
*Avoid snacks before bedtime*
- While heavy meals before bedtime can disrupt sleep, this patient reports having only a **light snack**, which is unlikely to be the primary cause of his significant daytime sleepiness.
- There is no mention of indigestion or gastrointestinal discomfort after the snack that would point to this as a problem.
*Decrease exercise intensity*
- Regular exercise generally **improves sleep quality**, and there's no indication that the patient's exercise routine is negatively impacting his sleep.
- While very intense exercise too close to bedtime can be disruptive for some, exercise itself is generally beneficial for sleep and overall health; therefore, reducing it would not be a primary recommendation.
*Take a nap in the afternoon*
- While naps can temporarily alleviate daytime sleepiness, they can also **disrupt nighttime sleep patterns** by reducing sleep drive.
- Napping would be treating the symptom rather than the root cause, which is a **chronic lack of sufficient nighttime sleep**.
Question 84: A 4-year-old girl presents to the office with her parents who are concerned about their daughter and slow, progressive changes in her behavior. The girl was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines and was meeting all developmental milestones until about 2 years ago. At one point she had a vocabulary of several words and now she verbalizes in grunts. She also flaps her hands in a repeated motion and has difficulty walking. Her parents have tried several home therapies to improve their daughter's symptoms including restricted diets, hydrotherapy, and a variety of nutritional supplements. The vital signs include: heart rate 90/min, respiratory rate 22/min, blood pressure 110/65 mm Hg, and temperature 36.9°C (98.4°F). On physical exam, she is well nourished and stares absently out the window. Her heart has a regular rate and rhythm and her lungs are clear to auscultation bilaterally. She has mild scoliosis. Which of the following is the most likely diagnosis?
A. Autistic spectrum disorder
B. Tourette syndrome
C. Cerebral palsy
D. Phenylketonuria
E. Rett syndrome (Correct Answer)
Explanation: ***Rett syndrome***
- This presentation of a 4-year-old girl with previously met milestones, followed by **regression in language** (verbalizing in grunts), **loss of purposeful hand movements** (flapping hands), **gait abnormalities**, and **scoliosis**, is highly characteristic of Rett syndrome.
- Rett syndrome is a **neurodevelopmental disorder** found almost exclusively in girls caused by a mutation in the **MECP2 gene**, which typically manifests between 6 and 18 months of age with a period of normal development followed by regression.
*Autistic spectrum disorder*
- While autism involves **social and communication deficits** and **repetitive behaviors**, it typically presents earlier and does not usually involve a distinct period of **normal development followed by severe regression** in purposeful hand use and gait.
- The specific pattern of regression, especially the loss of purposeful hand movements, is more indicative of Rett syndrome than autism.
*Tourette syndrome*
- Tourette syndrome is characterized by **multiple motor tics** and **one or more vocal tics**, which can wax and wane.
- It does not typically involve the **profound developmental regression** in language, purposeful hand movements, and gait that this patient is experiencing.
*Cerebral palsy*
- Cerebral palsy is a group of **permanent movement disorders** that appear in early childhood, but it is caused by **non-progressive brain damage** or abnormal development, often prenatal or perinatal.
- It does not involve a period of **normal development followed by regression** of acquired skills, which is a hallmark feature in this case.
*Phenylketonuria*
- **Phenylketonuria (PKU)** is a metabolic disorder that can cause **intellectual disability**, seizures, and behavioral problems if untreated.
- However, it is usually screened for at birth, and prompt dietary intervention can prevent severe neurological damage; it does not typically present with the specific pattern of **developmental regression** seen here, particularly with respect to purposeful hand movements and gait.
Question 85: A concerned mother presents to clinic stating that her 14-year-old son has not gone through his growth spurt. She states that, although shorter, he had been growing at the same rate as his peers until the past year. There is no evidence of delayed puberty in the mother, but the father's history is unknown. The patient has no complaints. On physical exam, the patient is a healthy-appearing 14-year-old boy whose height is below the third percentile and whose weight is at the 50th percentile. His bone age is determined to be 11 years. A laboratory workup, including thyroid stimulating hormone (TSH), is unremarkable. What is the most likely diagnosis?
A. Hypothyroidism
B. Familial short stature
C. Constitutional growth delay (Correct Answer)
D. Growth hormone deficiency
E. Celiac disease
Explanation: ***Constitutional growth delay***
- This condition is characterized by **delayed bone age**, normal growth velocity initially followed by a deceleration, and an eventual **catch-up growth spurt** leading to normal adult height. The patient's history of being shorter than peers but growing at the same rate, followed by a recent slow down, and a bone age of 11 years (compared to his chronological age of 14) strongly indicates this.
- The absence of other symptoms, **unremarkable lab workup** (including TSH), and the fact that he was previously growing at the same rate as peers further supports constitutional growth delay, which is often linked to a family history of delayed puberty, even if the mother's history is negative and the father's is unknown.
*Hypothyroidism*
- **Hypothyroidism** would typically present with symptoms such as fatigue, weight gain, constipation, and cold intolerance, none of which are mentioned in the patient's history.
- The **unremarkable TSH** level rules out hypothyroidism as the cause of growth delay in this case.
*Familial short stature*
- In **familial short stature**, children typically grow along a short but otherwise normal percentile curve, and their bone age would typically match their chronological age.
- The patient's growth deceleration and significantly **delayed bone age** are inconsistent with familial short stature.
*Growth hormone deficiency*
- **Growth hormone deficiency** often presents with a significant deceleration of growth velocity and very short stature for age, but usually the bone age delay is more pronounced or proportional to the chronological age.
- While low height is present, the **otherwise healthy appearance** and absence of other metabolic or health issues make constitutional growth delay more likely, especially with the provided bone age and normal lab results.
*Celiac disease*
- **Celiac disease** can cause growth delay, but it would typically be accompanied by gastrointestinal symptoms such as abdominal pain, diarrhea, or malabsorption-related issues like weight loss or anemia.
- This patient is **asymptomatic** and has a normal weight for his height percentiles, which makes celiac disease an unlikely diagnosis.
Question 86: An 8-year-old boy is brought to the hospital because of blurred vision and headache for 3 months. During this period, the father has noticed that the child has been tilting his head back to look straight ahead. The patient has also had difficulty falling asleep for 2 months. He has had a 3.5 kg (7.7 lb) weight loss over the past 6 months. His temperature is 37.7°C (99.8°F), pulse is 105/min, and blood pressure is 104/62 mm Hg. Examination shows equal pupils that are not reactive to light. The pupils constrict when an object is brought near the eye. His upward gaze is impaired; there is nystagmus and eyelid retraction while attempting to look upwards. Neurologic examination shows no other focal findings. Which of the following is the most likely sequela of this patient's condition?
A. Diabetes insipidus
B. Blindness
C. Subarachnoid hemorrhage
D. Diabetic ketoacidosis
E. Precocious puberty (Correct Answer)
Explanation: ***Precocious puberty***
- The constellation of **Parinaud syndrome** (impaired upward gaze, nystagmus, eyelid retraction, and pupillary abnormalities) combined with symptoms of **increased intracranial pressure** (headache, blurred vision, weight loss, difficulty sleeping) in a child points to a **pineal tumor**, specifically a **germinoma**.
- Pineal germinomas are known to secrete **human chorionic gonadotropin (hCG)**, which can cross-react with LH receptors, leading to stimulation of **testosterone production** and subsequent **precocious puberty** in boys.
*Diabetes insipidus*
- While diabetes insipidus can be associated with suprasellar tumors, it's less commonly a direct sequela of a **pineal germinoma** itself compared to precocious puberty, although mass effect on the hypothalamus could potentially lead to it.
- The primary symptoms described are classic for **Parinaud syndrome** and increased intracranial pressure, not specific signs of diabetes insipidus (e.g., polyuria, polydipsia).
*Blindness*
- **Vision loss or blindness** can occur due to long-standing **papilledema** from increased intracranial pressure, or direct compression of the **optic chiasm** or **optic nerves** by a large tumor.
- While a possible serious complication, **precocious puberty** is a more specific and direct endocrinological sequela linked to the hormonal activity of a pineal germinoma in boys.
*Subarachnoid hemorrhage*
- Although any intracranial tumor can potentially bleed, a **subarachnoid hemorrhage** typically presents with a sudden onset of **"thunderclap" headache**, stiff neck, and altered consciousness.
- The patient's symptoms have been evolving over 3 months, which is inconsistent with the acute presentation of a subarachnoid hemorrhage.
*Diabetic ketoacidosis*
- **Diabetic ketoacidosis (DKA)** is a severe complication of **type 1 diabetes mellitus**, characterized by hyperglycemia, metabolic acidosis, and ketonemia.
- There are no clinical signs or symptoms in this presentation (e.g., polyuria, polydipsia, Kussmaul respirations, fruity breath) to suggest uncontrolled diabetes or DKA, and it is not a direct sequela of a pineal tumor.
Question 87: An 18-month-old boy is brought to the physician by his mother because of concern that he has not yet begun to walk. He was born at term and exclusively breastfed until 15 months of age. His mother says he has been well, apart from an episode of high fever and seizure 4 months ago for which she did not seek medical attention. He has an older brother who is currently receiving medical treatment for failure to thrive. His parents have no history of serious illness; they are of normal height. His last vaccine was at the age of 4 months. He is at the 20th percentile for length, 10th percentile for weight, and 50th percentile for head circumference. Physical examination shows dry mucous membranes and erosion of the enamel on the lingual surface of the incisors and carious molars. He has frontal bossing. His wrists are widened, his legs seem bent, and there is beading of the ribs. Which of the following is the most likely underlying cause of this patient's delay in walking?
A. Deficiency of osteoclasts to reabsorb bone
B. Osteoid proliferation in the subperiosteal bone
C. Defect in type I collagen
D. Mutation of fibroblast growth factor receptor 3
E. Defective growth plate mineralization (Correct Answer)
Explanation: ***Defective growth plate mineralization***
- The patient's symptoms, including **delayed walking**, **frontal bossing**, **widened wrists**, **bowed legs** (bent legs), and **rachitic rosary** (beading of the ribs), are classic signs of **rickets**.
- **Rickets** is caused by a deficiency of vitamin D, leading to impaired mineralization of the cartilage and newly formed bone at the growth plates, resulting in soft and weak bones. The prolonged **exclusive breastfeeding** in this case, without vitamin D supplementation, increases the risk.
*Deficiency of osteoclasts to reabsorb bone*
- This describes conditions like **osteopetrosis** (Albers-Schonberg disease), which typically presents with **dense, brittle bones**, prone to fractures, and often associated with **bone marrow failure**.
- While osteopetrosis can cause skeletal deformities and delayed milestones, the specific findings of widened wrists, bowed legs, and rachitic rosary are not characteristic of osteopetrosis, which involves increased bone density.
*Osteoid proliferation in the subperiosteal bone*
- This is a feature of conditions like **secondary hyperparathyroidism** or some bone tumors, which do not typically present with the widespread skeletal deformities and growth plate abnormalities seen in rickets.
- While it can lead to bone pain and fragility, it does not explain the characteristic signs of rickets, such as widened growth plates and bone softening.
*Defect in type I collagen*
- A defect in type I collagen is characteristic of **osteogenesis imperfecta**, a genetic disorder leading to **brittle bones** that are prone to frequent fractures.
- Patients with osteogenesis imperfecta often have **blue sclerae** and **dentinogenesis imperfecta** (which can cause dental issues, but not specifically enamel erosion and caries in the manner described), but not the specific rickets-like skeletal deformities.
*Mutation of fibroblast growth factor receptor 3*
- A mutation in **fibroblast growth factor receptor 3 (FGFR3)** causes **achondroplasia**, the most common form of dwarfism.
- Achondroplasia is characterized by **short limbs**, a **normal trunk size**, and a **large head with frontal bossing**, but it does not cause the specific skeletal findings of widely spaced growth plates, bowed legs, and rachitic rosary associated with defective mineralization.
Question 88: An 8-year-old boy presents to his pediatrician for a well visit. His parents state that he has been doing well in school and has many friends. The patient is a member of the chess club and enjoys playing video games. He has a past medical history of asthma which is treated with albuterol. The patient is in the 99th percentile for weight and 30th percentile for height. His temperature is 99.5°F (37.5°C), blood pressure is 122/88 mmHg, pulse is 90/min, respirations are 11/min, and oxygen saturation is 98% on room air. The patient's body mass index is 39.1 kg/m^2 at this visit. On physical exam, you note a young boy who maintains eye contact and is excited to be at the doctor's office. Cardiopulmonary exam is within normal limits. Abdominal exam reveals normal bowel sounds and is non-tender in all 4 quadrants. Neurological and musculoskeletal exams are within normal limits. Which of the following is the most likely outcome in this patient?
A. Constitutional growth delay
B. Precocious puberty
C. Hypertension
D. Slipped capital femoral epiphysis (Correct Answer)
E. Atherosclerotic heart disease
Explanation: ***Slipped capital femoral epiphysis***
- The patient's **obesity** (BMI 39.1 kg/m^2, 99th percentile for weight) is a significant risk factor for **slipped capital femoral epiphysis (SCFE)**, especially during periods of rapid growth.
- SCFE presents with hip, groin, thigh, or knee pain and a limp, often requiring emergency surgical intervention to prevent further slippage and complications like avascular necrosis.
*Constitutional growth delay*
- This condition is characterized by **short stature** and delayed puberty, usually with a family history of delayed growth spurts.
- While it involves growth, it does not explain the patient's obesity or increased risk of musculoskeletal complications associated with it.
*Precocious puberty*
- Precocious puberty is defined by the onset of secondary sexual characteristics before age 8 in girls or age 9 in boys.
- While obesity can be a risk factor for earlier puberty, it is not the most immediate or likely outcome given the clinical scenario, and there are no signs of puberty mentioned.
*Hypertension*
- The patient's blood pressure (122/88 mmHg) is elevated for an 8-year-old and indicative of **hypertension**, a common comorbidity of obesity.
- However, while present, hypertension is a *current finding* and comorbidity, not a *future outcome* in the same immediate risk category as SCFE for an obese child of this age.
*Atherosclerotic heart disease*
- While obesity in childhood increases the long-term risk of **atherosclerotic heart disease**, this is a chronic process that develops over many years, typically manifesting in adulthood.
- It is a long-term consequence rather than the *most likely immediate outcome* during childhood, unlike conditions directly precipitated by childhood obesity.
Question 89: A 4-year-old boy is brought to the physician because of non-fluent speech. His mother worries that his vocabulary is limited for his age and because he cannot use simple sentences to communicate. She says he enjoys playing with his peers and parents, but he has always lagged behind in his speaking and communication. His speech is frequently not understood by strangers. He physically appears normal. His height and weight are within the normal range for his age. He responds to his name, makes eye contact, and enjoys the company of his mother. Which of the following is the most appropriate next step in management?
A. Referral to speech therapist
B. Evaluate response to methylphenidate
C. Psychiatric evaluation
D. Audiology testing (Correct Answer)
E. Thyroid-stimulating hormone
Explanation: ***Audiology testing***
- Before initiating any therapy for speech delay, it is crucial to rule out **hearing impairment**, as **undiagnosed hearing loss** is the most common organic cause of speech and language difficulties in children.
- **Standard practice guidelines** (AAP) recommend hearing assessment as the **first diagnostic step** in evaluating any child with speech or language delay.
- While other developmental aspects seem intact, the inability to use simple sentences at age 4 and speech that is "frequently not understood by strangers" strongly suggests the need to assess the child's ability to **receive auditory information**.
*Referral to speech therapist*
- While a **speech therapist referral** is highly appropriate for a child with significant speech delay, it should typically follow an assessment to rule out underlying organic causes like **hearing loss**.
- Without addressing potential hearing impairment, speech therapy may be less effective or miss the root cause of the communication difficulty.
*Evaluate response to methylphenidate*
- **Methylphenidate** is a stimulant medication used primarily for **attention-deficit/hyperactivity disorder (ADHD)**.
- There is no indication of ADHD symptoms in this child (e.g., inattention, hyperactivity, impulsivity), and it is not a treatment for **primary speech delay**.
*Psychiatric evaluation*
- The child's ability to respond to his name, make eye contact, and enjoy social interaction with family and peers makes a **primary psychiatric disorder** (like autism spectrum disorder) less likely to be the sole cause of the speech delay.
- Such an evaluation would typically be considered if **social communication deficits**, repetitive behaviors, or restricted interests were prominent.
*Thyroid-stimulating hormone*
- **Hypothyroidism** can cause developmental delays, including speech delay.
- However, the child's normal physical appearance, height, and weight make **congenital or acquired hypothyroidism** less likely to be the primary cause of his isolated speech delay.
Question 90: A previously healthy 6-month-old girl is brought to the physician by her mother for occasional “eye crossing.” Her mother says that the symptoms have become worse, especially before bedtime. The patient was born via cesarean delivery at 37-weeks' gestation and has met all developmental milestones. The patient's immunizations are up-to-date. She is at the 50th percentile for both length and weight. Her temperature is 36.7°C (98°F), pulse is 130/min, respirations are 40/min, and blood pressure is 90/60 mm Hg. Visual acuity is 20/20 in both eyes. There is an asymmetric corneal light reflection. When the left eye is covered, the right eye moves laterally. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in the management of this patient?
A. Measurement of intraocular pressure
B. Patching of the right eye
C. Urgent surgery
D. Reassurance and follow-up
E. Cyclopentolate eye drops bilaterally (Correct Answer)
Explanation: ***Cyclopentolate eye drops bilaterally***
- The patient exhibits signs of **strabismus** (eye crossing, asymmetric corneal light reflection, lateral movement of the right eye when the left is covered), which can lead to **amblyopia** if not corrected.
- **Cyclopentolate** eye drops cause **cycloplegia** (paralysis of the ciliary muscle) and **mydriasis** (pupil dilation), which are essential for a thorough ophthalmologic examination to determine the underlying cause and full extent of the strabismus, especially **refractive errors**.
*Measurement of intraocular pressure*
- While important in some ocular conditions, there are no signs or symptoms (e.g., pain, tearing, buphthalmos) suggestive of **glaucoma** in this patient.
- This measurement would not be the initial or most appropriate step for evaluating strabismus.
*Patching of the right eye*
- **Patching** is a treatment for **amblyopia** (lazy eye) to force the weaker eye to work harder, but it is typically initiated *after* a complete ophthalmologic evaluation to determine the cause of strabismus and the presence/severity of amblyopia.
- Applying a patch without a proper diagnosis, especially concerning refractive errors, could prevent a full evaluation and delay appropriate management.
*Urgent surgery*
- While surgery can be a treatment for strabismus, it is rarely urgent and is typically considered after other, less invasive interventions (like glasses or patching) have been tried or after a thorough evaluation reveals a significant deviation that is not amenable to conservative management.
- It's not the initial step in a 6-month-old.
*Reassurance and follow-up*
- Although some forms of strabismus can be intermittent or resolve spontaneously, the presence of an **asymmetric corneal light reflection** and **deviation on cover test** suggests true strabismus that requires intervention to prevent **amblyopia**.
- Delaying evaluation and intervention in an infant can lead to permanent vision loss in the affected eye.
