Pediatric Infectious Diseases

A $5$-year-old girl is brought to the emergency department due to a $12$-hour history of high fever, severe frontal headache, and repeated vomiting. Over the past $2$ hours, she has become increasingly somnolent and difficult to rouse. Her temperature is $39.5^\circ\text{C}$ ($103.1^\circ\text{F}$), blood pressure is $112/68\text{ mm Hg}$, pulse is $135/\text{min}$, and respirations are $26/\text{min}$. Physical examination reveals marked nuchal rigidity and a positive Brudzinski sign. Neurologic examination demonstrates a Glasgow Coma Scale score of $10$, sluggishly reactive pupils, and new-onset right-sided hemiparesis.

Arrange the following management steps in the most appropriate sequential order for this patient.

An 11-month-old boy is brought to the pediatric emergency department due to a 5-day history of high fever, harsh cough, nasal discharge, and red, watery eyes. Yesterday, a rash appeared on his face and has now spread down to his chest and back. His parents immigrated to the United States 3 months ago, and his immunization records are unavailable. His temperature is 39.6°C (103.3°F), heart rate is 165/min, and respiratory rate is 52/min with an oxygen saturation of 91% on room air. Physical examination reveals an irritable infant with a confluent, erythematous, maculopapular rash on the face, neck, and upper trunk. The oral mucosa has tiny white lesions on an erythematous base located on the inner cheeks. Lung auscultation reveals diffuse crackles and expiratory wheezing bilaterally. Chest radiography demonstrates diffuse, bilateral interstitial infiltrates without focal consolidation or pleural effusion. Which of the following is the most appropriate next step in the management of this patient?

Correlate each pediatric clinical presentation with the most appropriate primary therapeutic intervention or management strategy.

A $2$-day-old male newborn is evaluated in the hospital nursery for a newly developed skin rash. He was born at $39$ weeks gestation via uncomplicated vaginal delivery to a $28$-year-old mother who had comprehensive and normal prenatal care. The infant is breastfeeding well and has normal bowel and bladder output. His temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), heart rate is $130/\text{min}$, and respiratory rate is $40/\text{min}$. Physical examination reveals a well-appearing, alert neonate. There are multiple splotchy, erythematous macules, several of which have central $1$- to $2$-mm yellow-white pustules, scattered across his chest, back, and proximal thighs. The palms and soles are completely spared. The remainder of the physical examination is unremarkable. Which of the following is the most appropriate next step in management?

An infant, aged 21 days, is evaluated at an urgent care clinic for a one-day history of noisy breathing, frequent cough, and nasal congestion. The mother notes the infant's 4-year-old sister recently stayed home from preschool with a cold. The infant was born at 39 weeks gestation via uncomplicated vaginal delivery. Vital signs show a temperature of 37.2°C (99.0°F), heart rate of 155/min, respiratory rate of 62/min, and oxygen saturation of 95% on room air. Physical examination reveals mild subcostal retractions, copious clear nasal discharge, and diffuse bilateral wheezes and crackles on auscultation. Skin examination shows scattered, well-demarcated erythematous macules with small central yellow pustules predominantly on the chest and back. Which of the following is the most appropriate next step in management?

A 13-month-old girl is diagnosed with roseola infantum (exanthema subitum), a common childhood illness primarily caused by Human Herpesvirus 6 (HHV-6). Arrange the classic clinical events of this viral infection in the chronological order they typically occur.

A 4-year-old boy is brought to the emergency department by his parents due to a widespread rash. He recently immigrated from a region with low immunization rates and has not received any childhood vaccinations. For the past four days, he has had a high fever, severe cough, runny nose, and red, watery eyes. Yesterday, a red, non-pruritic rash appeared on his face and has since spread down to his chest and back. His temperature is $39.4^\circ\text{C}$ ($102.9^\circ\text{F}$), pulse is $125/\text{min}$, and respirations are $24/\text{min}$. Physical examination reveals a generalized erythematous maculopapular exanthem. Examination of the oral cavity shows tiny white spots on a red base on the buccal mucosa opposite the premolars. The patient is placed in an airborne isolation room. Which of the following is the most appropriate pharmacotherapy for this patient's underlying condition?

Congenital infections (often referred to as TORCH infections) can present with distinct clinical syndromes in the neonatal period. Match each characteristic clinical presentation described below to its most likely causative pathogen.

A 16-month-old male toddler presents to the outpatient clinic with a 3-day history of fever, irritability, and left ear tugging. According to his mother, the child developed a low-grade fever and clear rhinorrhea approximately one week ago. Current vital signs include a temperature of 38.7°C (101.7°F), a heart rate of 124/min, and a respiratory rate of 26/min. Otoscopic evaluation of the left ear reveals a distinctly bulging, erythematous tympanic membrane that lacks mobility upon pneumatic testing. The right tympanic membrane is translucent with a normal light reflex. The patient's medical history is unremarkable, and he has received no antibiotics in the past year. He has no known drug allergies. Which of the following is the most appropriate initial pharmacotherapy for this patient?

An unvaccinated $7$-month-old boy is evaluated in the pediatric clinic for a relentless cough. According to his parents, the illness started approximately $14$ days ago with mild nasal congestion and a low-grade fever. Over the past week, his cough has dramatically worsened into intense, rapid spasms. During these coughing fits, the infant becomes cyanotic around the mouth and frequently vomits his formula afterward. His temperature is $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), heart rate is $142/\text{min}$, respiratory rate is $38/\text{min}$, and oxygen saturation is $97\%$ on room air. On physical examination, the child appears well-nourished but has bilateral subconjunctival hemorrhages. Auscultation of the lungs reveals clear breath sounds bilaterally with no wheezing or crackles between coughing episodes. A complete blood count reveals a leukocyte count of $24,000/\text{mm}^3$ with $75\%$ lymphocytes. Which of the following is the most appropriate next step in management?

Emergency medical services bring an unvaccinated 4-year-old male to the resuscitation bay due to sudden-onset respiratory distress and high fever. The parents report he has been drooling excessively and refusing to swallow. On observation, the child is extremely anxious, leaning forward with his neck hyperextended and resting his hands on his knees. Loud inspiratory stridor is heard. Arrange the following acute management steps in the most appropriate chronological sequence for this patient.

A 5-year-old girl is admitted to the pediatric ward with severe right thigh pain, fever, and an inability to bear weight. Magnetic resonance imaging confirms acute hematogenous osteomyelitis of the right femur. She is empirically started on a regimen of intravenous vancomycin and ceftriaxone. On hospital day 3, her clinical condition has significantly improved, and she has been afebrile for 24 hours. Blood cultures and a deep tissue aspirate obtained on admission both grow *Staphylococcus aureus*. Antimicrobial susceptibility testing reveals the isolate is resistant to penicillin, but susceptible to oxacillin, cefazolin, and clindamycin. The patient has no known drug allergies. Which of the following is the most appropriate antimicrobial regimen for this patient at this time?

Match each classic pediatric clinical presentation with its most likely causative pathogen.

A 6-year-old girl is brought to the pediatric oncology clinic by her father. The patient has acute lymphoblastic leukemia and is currently in the maintenance phase of chemotherapy, which includes daily oral mercaptopurine and weekly oral methotrexate. The father is concerned because the patient's 8-year-old brother was diagnosed with chickenpox yesterday after developing a widespread, pruritic, vesicular rash. The brother's symptoms began 48 hours ago. The patient has no history of clinical chickenpox. Review of her medical record indicates she received her first dose of the varicella vaccine at 12 months of age but missed the second dose. She is currently afebrile and asymptomatic, with an unremarkable physical examination. Which of the following is the most appropriate next step in management?

A 14-month-old boy is brought to the emergency department due to a 4-day history of high fever, severe respiratory distress, and a progressively worsening rash. His medical history is significant for a conotruncal cardiac anomaly (truncus arteriosus) that was surgically repaired at 1 week of age. His neonatal intensive care course was complicated by recurrent generalized tonic-clonic seizures that resolved after intravenous calcium gluconate infusions. He has had no recent sick contacts and does not attend daycare. Three weeks ago, he received his routine 12-month childhood immunizations at a mobile health clinic.

On physical examination, his temperature is 39.5°C (103.1°F), heart rate is 175/min, and respiratory rate is 55/min. Oxygen saturation is 86% on room air. The patient appears lethargic and toxic. Skin examination reveals a diffuse eruption of umbilicated vesicles on an erythematous base covering his face, trunk, and extremities. Several of the vesicles are hemorrhagic. Chest auscultation reveals diffuse bilateral crackles.

Laboratory evaluation shows:
Leukocyte count: 3,200/mm³
Neutrophils: 80%
Lymphocytes: 15%
Monocytes: 5%
Serum calcium: 8.2 mg/dL (normal: 8.5–10.5 mg/dL)

Chest radiograph demonstrates diffuse, bilateral nodular interstitial infiltrates.

Which of the following is the most appropriate next step in targeted pharmacotherapy for this patient?

A 14-day-old male infant is brought to the pediatrician by his mother due to a 3-day history of bilateral eye redness and discharge. The infant was born at 39 weeks gestation via an unassisted home birth to a 22-year-old mother who received no prenatal care. Postnatal care was limited, and the infant did not receive prophylactic eye drops at birth. The infant is breastfeeding well, produces 6 to 8 wet diapers daily, and has no fever or cough. Vital signs are within normal limits for his age. Physical examination shows bilateral eyelid edema, marked conjunctival injection, and moderate mucopurulent discharge. The remainder of the physical examination is unremarkable. Which of the following is the most appropriate next step in management?

Match each pediatric patient presenting with suspected osteoarticular or disseminated infection to the most appropriate initial empiric antimicrobial regimen based on their specific clinical risk factors.

A 4-year-old unvaccinated boy is brought to the emergency department with a 2-day history of high fever, severe headache, and progressive lethargy. On physical examination, temperature is 39.4°C (102.9°F), heart rate is 130/min, respiratory rate is 28/min, and blood pressure is 105/65 mm Hg. He is somnolent but arousable and has marked nuchal rigidity. Neurologic examination reveals a new-onset right-sided hemiparesis. Arrange the following management steps in the most appropriate chronological order for this patient.

Match each pediatric infectious disease exposure scenario with the single most appropriate post-exposure prophylaxis (PEP) or management step.

An 18-day-old female newborn is evaluated in the pediatric emergency room after her parents noticed she was unusually difficult to arouse this morning. Over the past 2 days, she has fed poorly and felt warm to the touch. The pregnancy was complicated by a lack of prenatal care until the third trimester, but the delivery was a spontaneous vaginal birth at term. Her temperature is $38.8^\circ\text{C}$ ($101.8^\circ\text{F}$), pulse is $175\text{/min}$, and respiratory rate is $50\text{/min}$. The infant appears lethargic and has a bulging, tense anterior fontanelle. During the physical examination, she experiences a focal clonic seizure involving the left upper extremity. Careful inspection of her skin reveals multiple scattered erythematous patches containing $1\text{-mm}$ yellow-white pustules over her trunk and proximal limbs. Lumbar puncture is performed, and cerebrospinal fluid (CSF) analysis shows the following:

Gram stain of the CSF reveals no organisms. Which of the following intravenous antimicrobial regimens is the most appropriate initial therapy for this patient?