Pediatrics

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?

A pediatrics clerkship director is reviewing classic presentations of congenital heart diseases with medical students. Match each congenital heart defect to its most characteristic clinical or radiographic finding.

A 5-year-old boy is brought to the emergency department with a 1-day history of severe right hip pain and fever. He refuses to walk or bear any weight on his right leg. His temperature is 38.9°C (102.0°F). On physical examination, he appears irritable. His right hip is held rigidly in flexion, abduction, and external rotation; any attempt at passive range of motion elicits severe pain and crying. You suspect a severe acute joint infection. Arrange the following steps in the most appropriate sequential order for the standard diagnostic evaluation and management of this patient's condition.

A 14-week-old female infant is evaluated in the pediatric emergency department for increased work of breathing and diaphoresis during feeding. Over the past three weeks, her mother has noticed that she tires easily during nursing and fails to complete feeds. Her weight is below the 5th percentile, having previously tracked at the 50th percentile at birth. Vital signs demonstrate a temperature of 36.9°C (98.4°F), heart rate of 172/min, respiratory rate of 68/min, and oxygen saturation of 94% on room air. Physical examination reveals subcostal retractions and diffuse expiratory wheezes accompanied by basilar crackles bilaterally. Cardiac auscultation demonstrates a hyperdynamic precordium and a grade 4/6 harsh holosystolic murmur over the left lower sternal border with a palpable thrill. Palpation of the abdomen reveals hepatomegaly 3.5 cm below the right costal margin. Which of the following is the most appropriate next step in the management of this patient?

A 10-month-old girl is evaluated at an urgent care center during the winter season. Her parents report a two-day history of nasal congestion and a mild fever, which has now progressed to a worsening, raspy cough and increased work of breathing. She has been feeding less than usual today. The patient was born at term and has received all age-appropriate vaccinations. Her temperature is 38.0°C (100.4°F), pulse is 155/min, respirations are 58/min, and pulse oximetry is 94% on room air. Physical examination reveals a fussy infant with prominent nasal flaring and mild intercostal retractions. Lung auscultation demonstrates bilateral diffuse wheezing and scattered crackles. Which of the following is the most appropriate next step in the management of this patient?

A 3-year-old boy, who is fully immunized for his age, is rushed to the emergency department after a sudden onset of choking and gasping while eating peanuts 15 minutes ago. On arrival, he is in severe respiratory distress. Vital signs show a temperature of 37.2°C (99.0°F), a heart rate of 165/min, a respiratory rate of 52/min, and an oxygen saturation of 84% on room air. Lung examination reveals profound inspiratory stridor, marked suprasternal retractions, and significantly diminished breath sounds over the right hemithorax. While the physician is evaluating him, the child suddenly becomes cyanotic, unresponsive, and apneic. Arrange the following interventions in the most appropriate chronological order for managing this acute life-threatening emergency.

A 7-week-old male infant is evaluated in the emergency department due to progressive respiratory distress and extreme irritability. His parents report that over the past two weeks, he has begun sweating profusely and crying inconsolably after only a few minutes of breastfeeding. He often pauses to pant during feeds and appears pale. He has not gained weight since his 2-week pediatric visit. He was born at full term without complications. His temperature is 36.9°C (98.4°F), heart rate is 188/min, respiratory rate is 74/min, and blood pressure is 68/42 mm Hg. Oxygen saturation is 94% on room air. The infant appears lethargic, grayish, and is using severe intercostal and subcostal retractions to breathe. Pulmonary examination reveals diffuse expiratory wheezing and fine bibasilar crackles. Cardiovascular examination demonstrates a hyperactive precordium, a prominent S3 gallop, and a grade 3/6 holosystolic murmur heard best at the apex. The liver edge is palpated 5 cm below the right costal margin. Capillary refill is 4 seconds. An electrocardiogram demonstrates sinus tachycardia with deep, narrow Q waves and ST-segment elevations in leads I, aVL, V5, and V6. Which of the following is the most appropriate next step in the management of this patient?

Parents bring their 3-year-old son to the emergency department out of concern for his sudden onset of unsteadiness. According to his mother, the child began "walking like a drunk person" and falling frequently over the past 24 hours. He had a mild, unspecified febrile illness accompanied by a diffuse maculopapular rash approximately ten days prior to this presentation, which resolved completely without intervention. He has no history of head trauma and no access to medications or toxic substances. His temperature is $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure is $92/58\text{ mmHg}$, heart rate is $105\text{/min}$, and respiratory rate is $22\text{/min}$. On physical examination, the child is alert, fully oriented, and interactive. Neurologic examination reveals a wide-based, staggering gait and bilateral horizontal nystagmus. He demonstrates marked dysmetria when asked to reach for a toy. Muscle tone, strength, and deep tendon reflexes are normal and symmetric in all extremities. Fundoscopic examination reveals sharp optic disc margins with no evidence of papilledema. Which of the following is the most appropriate next step in the management of this patient?

A 4-year-old boy presents with a 1-day history of right hip pain and refusal to bear weight. His temperature is 38.9°C (102.0°F). Examination shows a toxic-appearing child with the right hip held in flexion, abduction, and external rotation. Initial laboratory testing reveals a white blood cell count of 16,000/mm³, an erythrocyte sedimentation rate (ESR) of 65 mm/h, and a C-reactive protein (CRP) of 8.2 mg/dL. Radiographs of the pelvis are unremarkable. Based on the suspected diagnosis, arrange the following subsequent steps in the correct chronological sequence for the optimal management of this patient.

A 2-year-old girl is brought to the pediatric urgent care clinic by her mother due to sudden right arm pain. Approximately one hour ago, while walking in the park, the child stumbled. To prevent her from falling, the mother reflexively pulled the child up by the right hand. The child immediately began crying and has since refused to move her right arm. Vital signs are within normal limits. On physical examination, the patient is calm when undisturbed but holds her right arm adducted against her body, slightly flexed at the elbow, and pronated. There is no visible swelling, erythema, or deformity of the clavicle, shoulder, elbow, or wrist. Palpation of the radial head elicits mild tenderness. Which of the following is the most appropriate next step in management?

A 10-year-old boy with a known history of type 1 diabetes mellitus is brought to the emergency department with altered mental status, deep and rapid breathing, and a fruity odor to his breath. Laboratory evaluation confirms the diagnosis of severe diabetic ketoacidosis (DKA). Arrange the following initial management steps in the correct chronological order according to standard pediatric DKA treatment protocols.

Match the following rare congenital adrenal hyperplasia variants and related steroidogenesis defects with their most characteristic clinical and laboratory presentations in neonates.

A 5-month-old boy is brought to the pediatric emergency department due to a 3-day history of weak crying, poor feeding, and progressively decreased spontaneous movements. His parents report that he has not had a bowel movement for the past 4 days. The infant was previously healthy and exclusively breastfed, but the parents recently began giving him homemade fruit purees sweetened with a small amount of honey. On physical examination, temperature is 37.1°C (98.8°F), heart rate is 130/min, and respiratory rate is 32/min. The infant appears lethargic with profound generalized hypotonia, a weak gag reflex, and poor head control. Pupils are dilated and sluggishly reactive to light. Deep tendon reflexes are diminished bilaterally. Which of the following statements regarding the diagnosis and management of this patient's condition are correct? (Select all that apply)

During a routine well-child visit, the parents of an 18-week-old female infant express concern regarding her feeding habits. They note that she consistently breaks into a sweat and appears fatigued after only a few minutes of bottle feeding. The patient's weight has dropped from the 50th percentile at birth to below the 5th percentile. Vital signs indicate a heart rate of 162/min and a respiratory rate of 68/min, with an oxygen saturation of 98% on room air. Auscultation of the lungs reveals scattered expiratory wheezes. Cardiac auscultation demonstrates a hyperdynamic precordium and a loud, harsh holosystolic murmur over the left lower sternal border. The abdomen is soft, but the liver edge is palpable 3.5 cm below the right costal margin. Which of the following is the most appropriate next step in the management of this patient?

An 18-month-old girl is brought to the pediatric neurology clinic by her parents due to recurrent episodes of rhythmic jerking of her right arm and leg. The episodes last about 2 minutes and have occurred three times over the past month. Her past medical history is notable for a large, unilateral, dark red, non-blanching macular lesion over the left side of her face, involving the forehead and upper eyelid, which has been present since birth. Her parents are very anxious and express concern regarding her overall development. They report that she walks independently and has a vocabulary of about 15 words, but they are deeply worried because she cannot yet run, kick a ball, or combine two words into a phrase. Which of the following statements regarding this patient's diagnosis and management are accurate? (Select all that apply)

An 8-year-old boy is brought to the pediatric clinic by his parents due to concerns raised by his second-grade teacher. Over the past month, the teacher noted that the child frequently "spaces out" and stops responding during lessons. These episodes consist of blank staring, occasional lip smacking, and last for 10 to 15 seconds. They occur multiple times a day. He does not lose postural tone or fall to the ground. Immediately following the episodes, he resumes his previous activity without any confusion or lethargy. His parents initially thought he was simply daydreaming or distracted, as he recently recovered from a mild respiratory illness with coughing and wheezing. Today in the clinic, his temperature is 37.1°C (98.8°F), blood pressure is 105/65 mm Hg, pulse is 88/min, and respirations are 18/min. A detailed neurologic examination is unremarkable. Having the patient blow on a pinwheel for two minutes in the office triggers an identical staring episode. Which of the following is the most appropriate initial pharmacotherapy for this patient's underlying condition?

Parents bring their 16-week-old male infant to the pediatric evaluation center due to persistent, forceful vomiting and extreme fussiness that has worsened over the past two days. The mother notes that the baby's eyes appear to be constantly looking downward, which she describes as a 'setting sun' appearance. Pregnancy and spontaneous vaginal delivery at 39 weeks of gestation were unremarkable. Vital signs show a temperature of 37.2°C (99.0°F), a heart rate of 115/min, and blood pressure of 105/65 mmHg.

On examination, the infant has a noticeably enlarged head with a tense, protruding anterior fontanelle and engorged scalp veins. The sagittal suture is palpably diastatic. Neurologic assessment confirms an upward gaze palsy with light-near dissociation. Lower extremity tone is mildly hypertonic. Dermatologic exam notes a scattering of small, erythematous papules with central pustules confined to the bilateral cheeks. The parents are anxious, mentioning he hasn't learned to roll from his back to his tummy yet, and they are upset with their primary pediatrician for not taking action when his head circumference crossed two major percentile lines a month ago.

A point-of-care cranial ultrasound indicates marked expansion of the lateral and third ventricles, while the fourth ventricle appears normal.

Which of the following interventions represent the most appropriate immediate steps in the management of this patient? (Select 2)