Pediatrics

Match each pediatric patient's clinical and laboratory presentation to the most likely underlying diagnosis and its associated pathophysiologic mechanism.

A 9-month-old male infant is brought to the pediatric clinic by his parents due to severe, chronic constipation and poor weight gain. The parents report that he has a bowel movement only once every 5 to 6 days, often requiring significant straining, and his abdomen frequently appears noticeably swollen. He was born at 39 weeks gestation and passed his first meconium at 50 hours of life. His diet consists of breast milk and age-appropriate pureed solids. His weight has fallen from the 45th percentile at birth to the 10th percentile currently. Vital signs are within normal limits for age. Physical examination reveals a distended, tympanitic abdomen. Upon digital rectal examination, there is increased anal sphincter tone and an empty rectal vault; withdrawal of the examining finger is immediately followed by an explosive expulsion of foul-smelling liquid stool and gas. Which of the following is the most accurate test to confirm the diagnosis in this patient?

A $2$-year-old boy with sickle cell disease (HbSS) is brought to the emergency department by his parents due to profound weakness and a rapidly enlarging abdomen over the past $6$ hours. He has been unusually sleepy and difficult to arouse. His temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), heart rate is $168/\text{min}$, blood pressure is $70/40\text{ mm Hg}$, and respiratory rate is $32/\text{min}$. Physical examination reveals marked conjunctival pallor. His abdomen is distended, firm, and diffusely tender. The spleen edge is palpable $6\text{ cm}$ below the left costal margin, which is a new finding compared to his baseline. Capillary refill time is $4$ seconds. Laboratory studies reveal:

Hemoglobin: $4.2\text{ g/dL}$ (baseline $8.5\text{ g/dL}$)
Reticulocytes: $14\%$
Platelets: $75,000/\text{mm}^3$
Leukocytes: $12,500/\text{mm}^3$

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

An 8-month-old girl arrives at the local emergency department because of progressive breathing difficulty and decreased oral intake over the last two days. Her illness began earlier in the week with clear nasal discharge and a mild cough. She was born at 39 weeks gestation without perinatal complications. Vital signs currently show a temperature of 38.0°C (100.4°F), heart rate of 148/min, respiratory rate of 62/min, and oxygen saturation of 89% on ambient air. Physical assessment demonstrates prominent nasal flaring, suprasternal retractions, and bilateral fine crackles accompanied by diffuse expiratory wheezing. Capillary refill time is 3 seconds, and the oral mucosa appears dry. According to current evidence-based guidelines for this condition, which of the following interventions are appropriate for this patient? (Select all that apply)

A 48-hour-old full-term neonate is evaluated in the neonatal intensive care unit for failure to pass meconium since birth. Over the past six hours, the infant has developed progressive abdominal distension and just had an episode of dark green vomiting. Vital signs show a heart rate of 158/min, respiratory rate of 48/min, temperature of 37.1°C (98.8°F), and blood pressure of 65/42 mmHg. Physical examination reveals a tensely distended, tympanitic abdomen with hypoactive bowel sounds, but no abdominal wall erythema or rigidity. Digital rectal examination reveals normal anal tone and an empty rectal vault with no stool expulsion upon withdrawal of the finger. Arrange the following steps in the most appropriate sequence for the evaluation and management of this patient.

A 4-week-old male infant is brought to the pediatric clinic by his parents for persistent jaundice. He was born at 39 weeks gestation via an uncomplicated vaginal delivery and has been exclusively breastfed. His parents note that over the past two weeks, his stools have become pale and clay-colored, and his urine stains the diaper dark yellow. He is feeding well and gaining weight appropriately. Vital signs are within normal limits for age. Physical examination reveals scleral icterus, jaundice, and a soft, non-distended abdomen with a liver edge palpable 3 cm below the right costal margin. Arrange the following diagnostic and therapeutic steps in the most appropriate sequential order for the evaluation and management of this patient's most likely condition.

A $6$-year-old boy is brought to the emergency department by his parents due to a new-onset fever and a mild cough that started earlier today. The patient was diagnosed with acute lymphoblastic leukemia (ALL) $4$ months ago and is currently receiving maintenance chemotherapy. His last chemotherapy cycle was $10$ days ago. His temperature is $39.4^\circ\text{C}$ ($102.9^\circ\text{F}$), pulse is $125/\text{min}$, respirations are $24/\text{min}$, and blood pressure is $95/60 \text{ mmHg}$. On physical examination, the child appears pale and mildly lethargic but is easily rousable. Lung auscultation is clear bilaterally without wheezing or crackles. There is a central venous port in the right upper chest with no surrounding erythema or induration.

Laboratory studies show:
Leukocyte count: $800/\mu\text{L}$
- Neutrophils: $15\%$
- Lymphocytes: $80\%$
- Monocytes: $5\%$
Hemoglobin: $9.2 \text{ g/dL}$
Platelet count: $85,000/\mu\text{L}$

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

A 5-year-old boy is rushed to the emergency department by his parents due to severe, sudden breathing difficulties that began earlier today. The family immigrated to the United States three weeks ago, and the child's vaccination records are unavailable. His parents note that he was completely healthy yesterday but developed a high fever and sore throat this morning. In the triage area, the child is noted to be highly anxious, leaning forward with his hands on his knees, and his chin thrust outward. He is continuously drooling and responds to questions with a quiet, muffled voice. Vital signs show a temperature of $39.5^\circ\text{C}$ ($103.1^\circ\text{F}$), heart rate of $148$/min, respiratory rate of $38$/min, and oxygen saturation of $94\%$ on room air. Marked suprasternal retractions are visible, and high-pitched inspiratory stridor is heard. Which of the following is the most appropriate next step in management?

Match each underlying pathophysiological or embryological mechanism with the corresponding pediatric gastrointestinal disorder.

A 7-year-old girl with a known history of moderate persistent asthma is brought to the emergency department by her parents due to rapidly worsening shortness of breath over the past 4 hours. At home, she received three doses of her albuterol inhaler with no improvement. On examination, the patient is agitated, speaking in single words, and leaning forward. Vital signs reveal a temperature of 37.1°C (98.8°F), heart rate of 145/min, respiratory rate of 42/min, and oxygen saturation of 87% on room air. Physical examination demonstrates marked suprasternal and intercostal retractions, diminished breath sounds bilaterally, and faint expiratory wheezes. Arrange the following therapeutic interventions in the most appropriate sequential order for managing this patient's acute severe status asthmaticus, from the most immediate initial step to the most advanced rescue therapy.

A pediatric oncology team is reviewing pathology, laboratory, and imaging reports for several newly admitted patients. Match each patient's characteristic diagnostic profile to the most accurate underlying solid tumor diagnosis.

Parents bring their 22-month-old son to the urgent care clinic late at night because he suddenly developed a harsh, 'seal-like' cough and noisy breathing. For the past two days, he has experienced clear nasal discharge and a low-grade temperature. On evaluation, the child appears anxious. His temperature is $38.2^\circ\text{C}$ ($100.8^\circ\text{F}$), heart rate is $145/\text{min}$, respiratory rate is $42/\text{min}$, and oxygen saturation is $95\%$ on ambient air. Physical examination reveals an audible, high-pitched noise during inspiration even when the child is calmed and resting on his mother's lap. This is accompanied by pronounced suprasternal and subcostal retractions. Auscultation of the lungs demonstrates equal air entry bilaterally without expiratory wheezing. Which of the following is the most appropriate next step in the management of this patient?

An adolescent girl, aged $10$, is evaluated in the outpatient hematology clinic due to recurrent epistaxis and progressive fatigue over the past three months. Her adoptive parents report she has always been significantly smaller than her peers. Vital signs are within normal limits for her age. Physical examination reveals short stature (below the $3$ rd percentile), microcephaly, an absent right thumb, and several flat, hyperpigmented macules across her abdomen and back. Laboratory testing shows a hemoglobin of $7.2 \text{ g/dL}$, a mean corpuscular volume of $112 \text{ fL}$, a leukocyte count of $1,800/\text{mm}^3$, and a platelet count of $22,000/\text{mm}^3$. Which of the following is the most likely underlying mechanism for this patient's clinical and laboratory findings?

A 30-month-old male is evaluated at an urgent care center due to a sudden onset of breathing difficulty. According to his caregiver, the toddler was eating mixed nuts in the kitchen when he experienced a severe choking episode. Although the violent choking subsided after several minutes, a persistent, dry cough and rapid breathing have continued. The patient has no significant past medical history and his immunizations are up to date. On physical examination, the child appears mildly distressed but is alert and appropriately interactive. His temperature is 37.1°C (98.8°F), pulse is 138/min, and respirations are 42/min. Oxygen saturation is 94% on room air. Pulmonary auscultation reveals diminished breath sounds over the right hemithorax and localized expiratory wheezing. An expiratory anteroposterior chest radiograph demonstrates hyperlucency of the right lung field and deviation of the mediastinal structures to the left. Which of the following is the most appropriate next step in the management of this patient?

Paramedics bring a $1.5$-year-old boy to the emergency department after his parents found him lethargic in his crib. According to the parents, the child developed sudden, intense abdominal pain $12$ hours ago, which was followed by multiple episodes of dark green vomiting. He has not passed stool or gas since the symptoms began. On examination, the child is obtunded. Temperature is $39.2^\circ\text{C}$ ($102.6^\circ\text{F}$), heart rate is $175/\text{min}$, respiratory rate is $50/\text{min}$, and blood pressure is $68/38\text{ mm Hg}$. Auscultation of the lungs reveals bilateral crackles and scattered wheezes, which the paramedics report began after he choked on his vomit during transport. The abdomen is markedly distended, rigid, and diffusely tender with involuntary guarding. Bowel sounds are absent. An upright abdominal radiograph displays prominent, dilated small bowel loops with multiple air-fluid levels and an absence of distal gas. Following initiation of intravenous fluid resuscitation, which of the following is the most appropriate next step in management?

A 5-year-old boy with a known history of severe hemophilia A is brought to the pediatric emergency department after falling from a playground structure and striking his head. His parents report that he has vomited twice since the fall and appears unusually lethargic. On primary survey, his airway is patent, breathing is unlabored, and perfusion is adequate. His Glasgow Coma Scale score is 13. Arrange the following management steps in the most appropriate chronological order.

An 8-year-old boy arrives at the pediatric emergency department via emergency medical services with severe difficulty breathing. The symptoms began abruptly while he was playing outdoors in cold weather. He has a documented history of moderate persistent asthma. En route to the hospital, paramedics administered three back-to-back doses of nebulized albuterol and ipratropium, as well as one dose of intramuscular epinephrine, with minimal clinical improvement.

On arrival, the patient appears visibly exhausted, diaphoretic, and is leaning forward in a tripod position. He is only able to speak in single words. Vital signs are temperature 37.0°C (98.6°F), heart rate 160/min, respiratory rate 48/min, and oxygen saturation 89% on a non-rebreather mask. Physical examination reveals severe suprasternal and subcostal retractions. Lung auscultation demonstrates a 'silent chest' with markedly diminished air entry bilaterally and no audible wheezing. A portable chest radiograph shows bilateral hyperinflation but no focal consolidations or pneumothorax.

Which of the following are the most appropriate immediate steps in the management of this patient? (Select all that apply)

Please pair the following pediatric gastrointestinal conditions with their most characteristic radiological finding on diagnostic imaging.

A 3-week-old full-term male is evaluated in the emergency department for sudden onset of bilious (green) vomiting. He has had two episodes in the past four hours. His prenatal course and birth history were unremarkable. On physical examination, the infant is awake and alert. Vital signs are within normal limits for age, and he is hemodynamically stable. The abdomen is soft, non-distended, and non-tender, with normal bowel sounds. Arrange the following steps in the most appropriate chronological order for the evaluation and management of this patient.

A $3$-year-old girl is brought to the pediatric emergency department at 4:00 AM by her parents. For the past $48$ hours, she has had rhinorrhea and a low-grade fever. Tonight, she awoke with a loud, brassy cough and difficulty breathing. Vital signs include a temperature of $38.1^\circ\text{C}$ ($100.6^\circ\text{F}$), a heart rate of $135\text{/min}$, a respiratory rate of $40\text{/min}$, and an oxygen saturation of $94\%$ on room air. Physical examination reveals an anxious but alert child with prominent inspiratory stridor at rest and visible intercostal retractions. Arrange the following clinical steps in the most appropriate chronological sequence for managing this patient's condition.