Pediatrics

A 2-year-old boy is brought to the emergency department due to refusal to walk for the past 12 hours. His parents note he was well yesterday but awoke crying and pointing to his right leg. His current temperature is $39.5^{\circ}C$ ($103.1^{\circ}F$). On examination, the child is irritable, and the right hip is held rigidly in flexion, abduction, and external rotation. Any attempt to move the joint elicits severe distress. Arrange the following diagnostic and therapeutic steps in the most appropriate chronological sequence for managing this patient's condition.

A 9-month-old girl is brought to the emergency department due to intermittent episodes of severe crying. During these episodes, she draws her legs up to her chest and appears to be in significant pain. Between episodes, she is calm and plays with her toys. Her parents report one episode of nonbilious emesis and note that her most recent diaper contained dark red, mucus-like stool. Her vital signs are stable, and abdominal examination reveals a palpable sausage-shaped mass in the right upper quadrant without guarding or rebound tenderness. Arrange the following steps in the standard chronological order of management for this patient.

An 8-year-old girl is admitted to the pediatric ward with a 6-day history of worsening productive cough, low-grade fever, and increasing shortness of breath. She has a past medical history of recurrent sinopulmonary infections, nasal polyps, and chronic malabsorption requiring daily pancreatic enzyme supplementation. Her immunizations, including the annual influenza vaccine, are up to date. On admission, her temperature is 38.5°C (101.3°F), blood pressure is 105/65 mmHg, heart rate is 118/min, and respiratory rate is 28/min. Pulse oximetry shows 92% on room air. Physical examination reveals digital clubbing, an increased anteroposterior chest diameter, and coarse crackles over the bilateral upper lung fields. Sputum analysis is performed, and the Gram stain demonstrates abundant neutrophils and Gram-negative bacilli that are oxidase-positive and non-lactose fermenting. Which of the following is the most appropriate antimicrobial regimen for this patient's acute respiratory exacerbation?

A $10$-month-old girl is admitted to the pediatric intensive care unit due to rapidly worsening work of breathing. She was born prematurely at $32$ weeks gestation and is fully immunized according to the standard schedule. Her current illness began $3$ days ago with nasal congestion and a low-grade temperature. The patient's father has severe persistent asthma, and she has a history of mild atopic dermatitis. Vital signs show a temperature of $38.1^\circ\text{C}$ ($100.6^\circ\text{F}$), heart rate of $175$/min, and respiratory rate of $68$/min. Oxygen saturation is $87\%$ on ambient air. Physical examination reveals an exhausted infant with marked suprasternal retractions, head bobbing, and diffuse bilateral expiratory wheezing mixed with coarse crackles. A chest radiograph demonstrates hyperinflation, flattened hemidiaphragms, and patchy atelectasis. Based on current pediatric guidelines, which of the following interventions are indicated in the immediate management of this patient? (Select all that apply)

Match each clinical presentation of a pediatric patient with the most likely underlying endocrine condition.

A 7-year-old boy with a history of meconium ileus in infancy presents to the pulmonary clinic for a routine follow-up. He has a chronic daily cough producing thick, purulent sputum and has required multiple hospitalizations for respiratory exacerbations. He is currently in the 10th percentile for weight and 15th percentile for height. Sweat chloride testing reveals a concentration of $95 \text{ mmol/L}$ (normal $<39 \text{ mmol/L}$). The patient's progressive pulmonary disease is driven by a well-described pathophysiologic cascade.

Arrange the following pathophysiologic events in the chronological sequence that leads to this patient's chronic lung disease, starting with the primary cellular defect.

A 2-year-old boy is brought to the pediatric emergency department with a 6-day history of high fever, bilateral non-exudative conjunctivitis, cracked red lips, and a polymorphous maculopapular rash on his trunk. Physical examination reveals cervical lymphadenopathy and erythema of the palms and soles. A clinical diagnosis of Kawasaki disease is made. Arrange the following steps in the correct chronological sequence for the standard management and follow-up of this patient.

A $9$-month-old boy is evaluated in the pediatric neurology clinic for a rapidly increasing head circumference. At his $6$-month well-child visit, his head circumference was at the $85^{\text{th}}$ percentile, but it has now crossed lines to the $99^{\text{th}}$ percentile. His weight and length continue to track along the $50^{\text{th}}$ percentile. The parents are extremely anxious; they have been reading about hydrocephalus and are concerned that he has a severe neurological delay because he only babbles, can pull himself to a stand, but cannot walk independently. On physical examination, the infant is playful and alert. The anterior fontanelle is open, soft, and flat. There is no sunsetting of the eyes, and muscle tone and deep tendon reflexes are normal. An ultrasound of the head reveals normal ventricular size and prominent subarachnoid spaces. Which of the following statements regarding this patient's presentation and management are true? (Select all that apply)

A 14-year-old boy is evaluated in the emergency department for a 3-day history of progressively worsening headache, blurred vision, and shortness of breath. Physical examination reveals pale conjunctivae, scattered petechiae, and bilateral retinal hemorrhages. Vital signs are temperature 37.8°C (100.0°F), heart rate 132/min, respiratory rate 28/min, and blood pressure 110/65 mmHg. Pulse oximetry shows 92% on room air.

Laboratory studies show:
Leukocytes: 380,000/mm³ (90% myeloblasts)
Hemoglobin: 5.2 g/dL
Platelets: 22,000/mm³
Uric acid: 9.8 mg/dL
Potassium: 4.8 mEq/L
Creatinine: 1.1 mg/dL

Arrange the following interventions in the most appropriate chronological sequence to safely manage this patient's acute presentation.

A 2-year-old boy is brought to the pediatric clinic by his parents after they noticed a large amount of dark red blood in his diaper this morning. The parents report the child has been entirely asymptomatic otherwise; he has had no fever, vomiting, abdominal pain, diarrhea, or changes in his appetite. His medical history is unremarkable, and he has reached all developmental milestones appropriately. Vital signs are within normal limits for his age. Physical examination reveals a soft, non-tender abdomen with normal active bowel sounds. Rectal examination shows dark blood in the vault but no anal fissures, skin tags, or palpable masses. Which of the following is the most appropriate next diagnostic test for this patient?

A 5-month-old boy is brought to the emergency department by his parents due to a persistent fever for the past 6 days. His mother reports he has been extremely irritable, feeding poorly, and has a mild, dry cough. A transient erythematous macular rash was noted on his trunk 3 days ago but has since resolved. His temperature is 39.8°C (103.6°F), heart rate is 175/min, blood pressure is 85/50 mmHg, and respiratory rate is 45/min. On physical examination, the infant is fussy but consolable. He has bilateral non-exudative conjunctival injection and erythematous, cracked lips. There is no cervical lymphadenopathy, and his hands and feet appear normal without edema or peeling. Breath sounds are clear bilaterally. Cardiac examination reveals a tachycardic, regular rhythm with no murmurs. Laboratory studies reveal:

Urinalysis demonstrates 25 leukocytes/hpf, negative nitrites, and no bacteria. Which of the following is the most appropriate next step in the management of this patient?

A 7-year-old girl is brought to the pediatrician by her father, who recently noticed that she is developing breasts and has experienced a rapid increase in height over the past year. Vital signs are within normal limits for her age. Physical examination reveals Tanner stage 3 breast development and Tanner stage 2 pubic hair. No axillary hair or acne is noted, and the neurological examination is unremarkable. The physician suspects an early onset of puberty. Arrange the following steps in the most appropriate chronological sequence for the diagnostic evaluation and management of this patient's condition.

A 3-year-old boy is evaluated in the pediatric neurology clinic for progressive unsteadiness. According to his parents, he achieved independent walking at 15 months of age, but his gait has always been 'clumsy.' Over the past year, his balance has deteriorated; he now sways continuously when standing and falls frequently. His medical history is significant for three prior hospitalizations for severe sinopulmonary infections presenting with wheezing and respiratory distress. Vital signs today are: temperature 37.1°C (98.8°F), blood pressure 95/60 mmHg, pulse 105/min, and respirations 22/min. On physical examination, the child exhibits a wide-based, truncal ataxia. Extraocular movement testing reveals impaired smooth pursuit and frequent saccadic intrusions. Close inspection of the eyes reveals prominent, dilated superficial blood vessels on the bulbar conjunctivae bilaterally. Deep tendon reflexes are absent in the lower extremities. The parents mention that he is due for his scheduled childhood immunizations today. Based on the most likely underlying diagnosis, which of the following is the most appropriate recommendation regarding this patient's care?

A 4-month-old boy is brought to the emergency department in January with a 3-day history of rapid breathing, poor feeding, and excessive diaphoresis during feeds. He was noted to have a 'heart murmur' at birth but has not been evaluated by a cardiologist. On physical examination, his temperature is 37.2°C (99.0°F), heart rate is 168/min, respiratory rate is 65/min, and blood pressure is 85/50 mm Hg in the right arm. Oxygen saturation is 94% on room air. Femoral pulses are 2+ and equal bilaterally, with no brachial-femoral delay. Lung auscultation reveals diffuse bilateral expiratory wheezes and fine basilar crackles. Cardiac examination demonstrates a hyperactive precordium, a 4/6 holosystolic murmur heard best at the left lower sternal border, and a prominent S3 gallop. The liver edge is palpable 4 cm below the right costal margin. Suspecting a severe respiratory infection, a resident physician administers nebulized albuterol and oral dexamethasone. Thirty minutes later, the infant becomes increasingly lethargic, his heart rate rises to 215/min, and his respiratory distress significantly worsens. Which of the following best describes the underlying pathophysiology of this patient's initial presentation, and why did the administered pharmacotherapy exacerbate his clinical deterioration?

An infant delivered at full term is admitted to the neonatal intensive care unit at 48 hours of life due to progressive lethargy, hypotonia, and Kussmaul respirations. Initial laboratory evaluation reveals a severe high anion gap metabolic acidosis ($pH\ 7.12$, $HCO_3^{-}\ 7\ mEq/L$), hypoglycemia ($34\ mg/dL$), and moderate hyperammonemia ($420\ \mu mol/L$). The clinical presentation is highly suspicious for an acute metabolic crisis secondary to an inborn error of metabolism, such as an organic acidemia. Arrange the following acute management and diagnostic steps in the most appropriate sequential order of priority for this patient.

An 18-month-old girl is brought to the pediatric clinic by her parents in late January due to fast breathing and a whistling sound from her chest. Over the past 48 hours, she has had copious clear rhinorrhea, a low-grade fever, and a slight decrease in oral intake. There is no family history of asthma or atopy, and she has had no previous episodes of similar symptoms. Her immunizations are up to date. Her temperature is 37.9°C (100.2°F), heart rate is 138/min, respiratory rate is 48/min, and oxygen saturation is 94% on room air. The patient appears alert but has mild subcostal retractions. Lung auscultation reveals diffuse polyphonic expiratory wheezing and coarse crackles bilaterally. Which of the following are the most appropriate management steps for this patient? (Select all that apply)

A $22$-month-old toddler is evaluated in the emergency department for a persistent cough and noisy breathing that started abruptly while he was eating a snack mix containing peanuts at a family gathering the previous day. Initially, he had a vigorous coughing fit that resolved after several minutes, prompting the parents to monitor him at home. Today, he developed a mild fever of $37.6^\circ\text{C}$ ($99.7^\circ\text{F}$) and ongoing tachypnea. He has no history of atopy, prior wheezing, or recent upper respiratory infections. Current vital signs show a heart rate of $128\text{/min}$, respiratory rate of $46\text{/min}$, and oxygen saturation of $93\%$ on room air. Physical examination reveals asymmetric chest expansion. Auscultation demonstrates prolonged expiration with a high-pitched wheeze exclusively over the right hemithorax. The left lung field has normal vesicular breath sounds. Which of the following is the most appropriate next step in management?

Match each classic clinical or imaging finding with its corresponding pediatric gastrointestinal diagnosis.

A 16-month-old boy is brought to the pediatric clinic for a routine well-child evaluation. His mother mentions that he is a picky eater and refuses most solid foods. His diet consists predominantly of $32$ to $40$ ounces (approximately $950$ to $1200 \text{ mL}$) of whole cow's milk daily, supplemented only by small amounts of crackers. He is active but occasionally appears more fatigued than his siblings did at this age. Vital signs are within normal limits. Physical examination reveals conjunctival pallor but no hepatosplenomegaly or lymphadenopathy. Laboratory studies show:

Hemoglobin: $8.4 \text{ g/dL}$
Mean corpuscular volume (MCV): $66 \text{ fL}$
Red cell distribution width (RDW): $19\%$ (normal: $11.5\% - 14.5\%$)
Reticulocyte count: $1.0\%$

Which of the following is the most likely diagnosis?

A 19-month-old boy is evaluated in the emergency department in mid-January for a 4-day history of nasal congestion, low-grade fever, and a worsening cough. Over the past 24 hours, his parents noted rapid breathing and poor oral intake. His medical history includes severe atopic dermatitis. Both parents have persistent asthma. He has had one previous episode of wheezing at 14 months of age during a viral illness. He is up to date on all recommended childhood immunizations.

His temperature is $38.1^\circ\text{C}$ ($100.6^\circ\text{F}$), pulse is $158/\text{min}$, respiratory rate is $62/\text{min}$, and oxygen saturation is $88\%$ on room air.

Physical examination reveals a tired-appearing toddler with marked subcostal and intercostal retractions, nasal flaring, and a prolonged expiratory phase. Copious yellowish-green mucus is noted in the nares. Lung auscultation demonstrates diffuse polyphonic wheezing and coarse crackles bilaterally.

A chest radiograph shows generalized hyperinflation, peribronchial cuffing, and a wedge-shaped opacity in the right upper lobe without air bronchograms.

A trial of nebulized albuterol is administered. Forty-five minutes later, his respiratory rate is $64/\text{min}$, oxygen saturation is $88\%$ on room air, and the wheezing is unchanged.

Which of the following is the most appropriate next step in the management of this patient?