All practice questions

Match the following pediatric endocrine conditions to their most characteristic clinical or laboratory presentation.

A 12-year-old boy is brought to the pediatric endocrinology clinic by his parents due to poor growth and increasing fatigue over the past 12 months. He used to be energetic but now frequently falls asleep in class. He also complains of feeling cold, even during the summer, and reports new-onset frequent morning headaches. Over the past year, his height has plateaued, falling from the 50th percentile to below the 10th percentile. Physical examination reveals a pale, prepubertal boy with dry skin and delayed relaxation phase of deep tendon reflexes. Visual field testing by confrontation reveals diminished peripheral vision bilaterally. Which of the following serum laboratory patterns is most likely present in this patient?

A $2$-hour-old term male neonate is evaluated in the neonatal intensive care unit for profound cyanosis that developed shortly after birth. His mother had an uncomplicated pregnancy and vaginal delivery. On initial evaluation, his oxygen saturation was $60\%$ on room air and failed to improve significantly during a hyperoxia test. An echocardiogram revealed D-transposition of the great arteries with an intact ventricular septum. An intravenous prostaglandin E1 infusion was promptly initiated. One hour later, the neonate becomes apneic, requiring endotracheal intubation and mechanical ventilation. Despite $100\%$ fraction of inspired oxygen ($FiO_2$) on the ventilator, his oxygen saturation remains at $58\%$. An arterial blood gas shows pH $7.15$, $PaCO_2$ $40$ mmHg, $PaO_2$ $25$ mmHg, and $HCO_3^-$ $14$ mEq/L. The patient is tachycardic and hypotensive. A repeat bedside echocardiogram demonstrates a widely patent ductus arteriosus and a severely restrictive patent foramen ovale bowing right-to-left. Which of the following is the next best step in management?

Match each clinical presentation of third-trimester or intrapartum vaginal bleeding with its most likely diagnosis.

Match each of the following pediatric congenital heart defects with its classic clinical or auscultatory finding.

A 5-year-old unimmunized boy is brought to the emergency department by his parents due to sudden onset of high fever, difficulty swallowing, and drooling. He is sitting upright, leaning forward with his neck extended, and appears toxic. He has marked inspiratory stridor and severe suprasternal retractions. Arrange the following steps in the most appropriate sequential order for the acute management of this patient.

A 6-month-old boy is brought to the pediatric clinic by his parents due to strange jerking movements that began two weeks ago. The parents report that he suddenly flexes his neck, trunk, and arms for 1 to 2 seconds. These movements occur in clusters of up to 20 episodes, typically just after he wakes from a nap. Previously, the infant had begun to roll over and smile, but he has not done either since these episodes started. He was born at 39 weeks' gestation without complications. Temperature is 37.0°C (98.6°F), heart rate is 120/min, and blood pressure is 85/50 mm Hg. Physical examination reveals three 1.5-cm elliptical, hypopigmented macules on his trunk that become more prominent under a Wood's lamp. The remainder of the examination shows decreased muscle tone. An electroencephalogram (EEG) demonstrates a high-amplitude, chaotic background with asynchronous, multifocal spikes and slow waves. Which of the following is the most appropriate next step in the management of this patient?

A 7-month-old boy is brought to the clinic by his parents due to "strange movements" that began two weeks ago. The parents report that the child has episodes where he suddenly bends his head and body forward while extending his arms stiffly. These episodes last for a few seconds, occur in clusters of 10 to 15, and typically happen just after he wakes up from a nap. Previously, the infant was able to sit with support and babble, but recently he has stopped vocalizing and seems less engaged with his surroundings. Vital signs are within normal limits for age. Physical examination reveals an infant who does not visually track objects well. Skin examination under a Wood lamp reveals three 2-cm elliptical hypopigmented macules on his trunk. An electroencephalogram (EEG) demonstrates a chaotic, high-voltage, asynchronous background with intermixed multifocal spikes and slow waves. Which of the following is the most appropriate initial pharmacotherapy for this patient's underlying condition?

A 10-month-old boy is brought to the emergency department by his parents following an episode of profound cyanosis. The parents report that he was crying inconsolably when he suddenly developed blue discoloration around his lips and began breathing very rapidly. His mother states she instinctively brought his knees to his chest, which seemed to gradually improve his color over several minutes. The patient has a history of a heart murmur, but the family recently immigrated and his medical records are unavailable. He is currently resting quietly. Vital signs are temperature 37.1°C (98.8°F), heart rate 130/min, respiratory rate 28/min, and blood pressure 85/50 mm Hg. Oxygen saturation is 94% on room air. Cardiac auscultation reveals a normal S1, a single S2, and a grade 3/6 harsh systolic ejection murmur heard best at the left upper sternal border. If a similar cyanotic episode recurs while the patient is in the emergency department, which of the following is the most appropriate next step in management?

An 8-year-old boy is brought to the clinic by his parents due to a 1-month history of right knee pain and a worsening right-sided limp. He has no history of trauma, fever, or recent illnesses. His parents note that he has been growing at a slower rate than his peers, falling from the 50th percentile to the 5th percentile for height over the past two years. His current weight is at the 30th percentile. The parents also report that he has been more fatigued lately and has developed constipation. Vital signs are within normal limits. On physical examination, the right knee has no effusion, erythema, or tenderness; range of motion is full and painless. Evaluation of the right hip reveals limited internal rotation. When the right hip is passively flexed, the thigh obligatorily rotates externally. Radiographs of the right hip show widening of the proximal femoral physis and posterior displacement of the femoral head relative to the femoral neck. Which of the following is the most appropriate next step in the management of this patient?

Match the following clinical vignettes of neonatal cyanotic heart disease with the most likely underlying congenital cardiac defect.

A 4-year-old boy presents to the emergency department with acute-onset limping and an inability to bear weight on his right lower extremity. His parents report that he developed a high fever earlier today. He was previously healthy and has no recent history of trauma. Temperature is 39.1°C (102.4°F), blood pressure is 100/65 mm Hg, and pulse is 125/min. On examination, the patient is distressed. The right hip is held in a position of flexion, abduction, and external rotation. Passive range of motion of the right hip elicits severe pain. There is no overlying erythema or swelling. Arrange the following steps in the most appropriate chronological order for the evaluation and management of this patient's condition.

A 7-month-old infant is brought to the pediatric clinic by his parents who report that he has been having recurrent episodes of sudden, brief, symmetric forward flexion of the neck and trunk with arm extension. These episodes occur in clusters, particularly when he is waking from sleep. Physical examination reveals three hypopigmented macules on his trunk that fluoresce under a Wood lamp. Which of the following additional clinical or diagnostic findings are most likely to be associated with this patient's underlying condition? (Select all that apply)

A 9-year-old boy is brought to the pediatrician by his parents for evaluation of fatigue, constipation, and poor growth. The parents report that he has been feeling cold even in warm weather and has not outgrown any of his clothes over the past year. Review of his growth chart shows a decline in height from the 50th percentile to the 10th percentile. Physical examination reveals dry skin and delayed relaxation of the ankle reflexes. Laboratory evaluation shows a free T4 level of $0.5 \text{ ng/dL}$ (normal: $0.9-1.7 \text{ ng/dL}$) and a thyroid-stimulating hormone (TSH) level of $2.1 \text{ }\mu\text{U/mL}$ (normal: $0.5-4.5 \text{ }\mu\text{U/mL}$). Which of the following is the most likely diagnosis?

A 3-year-old boy is brought to the emergency department by his parents due to a rapidly worsening sore throat, high fever, and difficulty breathing that began 4 hours ago. The parents recently immigrated and state the child has not received any childhood immunizations. On examination, the patient appears toxic, anxious, and is sitting leaning forward with his neck extended and chin thrust out. He is drooling and has a muffled voice. Temperature is 39.8°C (103.6°F), heart rate is 155/min, and respiratory rate is 42/min. Oxygen saturation is 91% on room air. Marked inspiratory stridor and suprasternal retractions are present.

Arrange the following interventions in the most appropriate chronological sequence for the management of this patient.

A 5-year-old boy is brought to the emergency department by his parents due to a sudden onset of right hip pain and a complete refusal to bear weight on his right leg since this morning. His temperature is 38.9°C (102.0°F). On physical examination, he appears uncomfortable and holds his right hip in a flexed, abducted, and externally rotated position. Any attempt at passive range of motion of the right hip elicits severe crying and guarding. The clinical suspicion for septic arthritis is high. Arrange the following diagnostic and therapeutic steps in the most appropriate sequential order for the management of this patient.

During a well-child visit, the parents of a $6$-year-old boy express concern about a change in their son's walking pattern. They report that for the past $8$ weeks, he has been favoring his right leg, especially after running or playing at the park. When asked if he has any pain, the child points to his right anterior thigh and the area just above his kneecap. The parents have not noticed any fevers, rashes, or recent illnesses. He has met all developmental milestones and has no significant past medical history. His temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), heart rate is $90/\text{min}$, and blood pressure is $98/60\text{ mm Hg}$. Physical examination reveals a well-appearing boy who walks with a right-sided antalgic gait and a noticeable drop of the left hemipelvis during the stance phase on his right leg. There is no visible swelling or erythema over the right knee or hip. Palpation of the knee elicits no tenderness, and knee range of motion is full and painless. However, placing the right hip in internal rotation and abduction provokes mild discomfort and is noticeably restricted compared to the left side. Blood tests reveal an erythrocyte sedimentation rate of $9\text{ mm/h}$ and a leukocyte count of $6,800/\text{mm}^3$. Which of the following is the most appropriate next step in the management of this patient?

Match each patient's clinical presentation to the most likely underlying cardiovascular anomaly.

Correlate each distinct clinical and laboratory vignette with its most accurate diagnosis.

An 18-month-old girl is brought to the pediatric clinic by her parents who have noticed she has been walking with a limp for the past 8 weeks. The parents report that her limp is most noticeable when she first wakes up in the morning or after naps, but her gait appears almost normal by the afternoon. She has no history of trauma, tick bites, or recent travel. She has not had any fevers, rashes, or weight loss. Vital signs are within normal limits. On physical examination, the right knee appears moderately swollen and is slightly warm compared to the left, but there is no overlying erythema. She resists full extension of the right knee but does not cry during the examination. Laboratory studies show a normal complete blood count, an erythrocyte sedimentation rate of 12 mm/h, and a C-reactive protein level of 0.3 mg/dL (normal < 1.0 mg/dL). Antinuclear antibody (ANA) testing is positive at a titer of 1:640, while rheumatoid factor is negative. Which of the following is the most appropriate next step in the management of this patient?