Paediatric Infections

Topics in this chapter

• Pediatric Respiratory Infections
• Viral Syndromes and Exanthems
• Neonatal and Congenital Infections
• Bacterial Throat Infections and Rheumatic Fever
• Infection Diagnosis and Microbiology
• Pediatric Infection Treatment
• Immunization and Infection Prevention

Practice questions

1. Question 1Q-3B6D87

   A 4-year-old unimmunized child is brought to the emergency department with a 2-day history of a sore throat, low-grade fever, and progressive respiratory distress. Examination reveals a pale child with a thick, adherent grayish-white pseudomembrane covering the tonsils and pharynx, which bleeds upon attempted removal. There is marked cervical lymphadenopathy giving a 'bull-neck' appearance. What is the primary mechanism of pathogenesis of the most likely causative organism?

   1. A.Inhibition of protein synthesis via ADP-ribosylation of elongation factor 2 (EF-2)
   2. B.Activation of adenylate cyclase leading to increased intracellular cAMP
   3. C.Cleavage of synaptobrevin preventing inhibitory neurotransmitter release
   4. D.Inhibition of acetylcholine release at the neuromuscular junction
   See the answer and solution
2. Question 2Q-A8A035

   A 6-month-old infant is brought with a 3-day history of high-grade fever that abruptly defervesced today, followed immediately by the appearance of a blanching, pinkish-maculopapular rash starting on the trunk and spreading to the neck and extremities. The infant is otherwise alert and plays actively. What is the most likely diagnosis?

   1. A.Measles (Rubeola)
   2. B.Rubella (German Measles)
   3. C.Exanthem subitum (Roseola infantum)
   4. D.Erythema infectiosum
   See the answer and solution
3. Question 3Q-05CB81

   An 8-year-old boy presents with fever, sore throat, and bilateral tender anterior cervical lymphadenopathy. Examination of the oropharynx reveals bright red tonsils with yellowish-white exudates and palatal petechiae. There is no cough or rhinorrhea. Rapid antigen detection test is positive for Streptococcus pyogenes. Which of the following is the most important objective of initiating antimicrobial therapy in this patient?

   1. A.Prevention of acute glomerulonephritis
   2. B.Prevention of acute rheumatic fever
   3. C.Prevention of suppurative peritonsillar abscess
   4. D.Reduction of the duration of acute pharyngitis symptoms
   See the answer and solution
4. Question 4Q-C730FD

   A 3-week-old neonate presents with poor feeding, lethargy, and a bulging anterior fontanelle. A lumbar puncture is performed, and cerebrospinal fluid (CSF) analysis reveals pleocytosis with neutrophil predominance, low glucose, and high protein. Gram stain shows Gram-positive bacilli. Which of the following is the most appropriate empiric antibiotic regimen for this patient?

   1. A.Ampicillin plus Cefotaxime
   2. B.Ceftriaxone plus Vancomycin
   3. C.Ampicillin plus Gentamicin
   4. D.Vancomycin plus Meropenem
   See the answer and solution
5. Question 5Q-F602C9

   A 2-year-old child presents with a 'barking' cough, inspiratory stridor, and hoarseness of voice that worsens at night. A soft tissue neck X-ray shows subglottic narrowing known as the 'steeple sign'. What is the single most effective pharmacological intervention for this condition?

   1. A.Inhaled beta-2 agonists
   2. B.Systemic corticosteroids
   3. C.Intravenous broad-spectrum antibiotics
   4. D.Inhaled recombinant DNAase
   See the answer and solution