A 4-year-old boy comes to the pediatrician with his mother with a 3-day history of cough and runny nose with decreased oral intake over the past 24 hours. His activity level has been normal and he has been attending school until this morning. He has no medical history or known allergies, but he has not received any of the recommended vaccines due to parental refusal. His temperature is 100.3°F (37.9°C), blood pressure is 98/62 mmHg, pulse is 85/min, respirations are 22/min, and oxygen saturation is 98% on room air. On examination, the child is fussy. Bilateral conjunctivae are injected, and there is redness on and around the tonsils. There is no lymphadenopathy. Faint rhonchi are heard at the lung bases bilaterally. Which of the following is the most appropriate next step in management?
Amoxicillin
Obtain chest radiography and respiratory virus panel
Supportive care with return precautions
Administer antitoxin and toxoid vaccine
Supportive care with return precautions
This boy presenting with 3 days of progressive fever, rhinorrhea, cough, conjunctivitis, and tonsilar erythema most likely has viral pharyngitis. The appropriate treatment for this is supportive care with return precautions (instructing the mother to bring the child back to a physician if he becomes short of breath).

Viral pharyngitis in children is most often caused by adenovirus, though other viruses can cause the condition as well. The diagnosis is clinical, with a presentation of fever, rhinorrhea, conjunctivitis, sore throat, and cough. Features that can help distinguish viral pharyngitis from pneumonia include a lack of tachypnea, increased work of breathing, hypoxemia, or adventitial lung sounds. No additional testing or intervention is necessary. The illness is typically self-limited and resolves with supportive care.

Shapiro et al. study features predictive of group A streptococcal (GAS) pharyngitis in children. The authors found that among patients with features of viral illness, patients older than 11 years of age who did not have a fever, cervical lymphadenopathy, or tonsillar exudates were at the lowest risk for GAS. The authors recommend against testing low-risk children for GAS to avoid antibiotic treatment in patients merely colonized with GAS.

Incorrect Answers:
Answer A: Administering antitoxin and toxoid vaccine is the treatment for Corynebacterium diphtheriae infection. Although this child has not received his age-appropriate vaccinations, his presentation is not concerning for infection with diphtheria. C. diphtheriae infection presents with cervical lymphadenopathy and gray pseudomembranes on pharyngeal exam, neither of which this child has.

Answer B: Amoxicillin should be given in cases of group A streptococcal (GAS) pharyngitis. Before amoxicillin is prescribed, testing with Streptococcal rapid antigen detection testing should be performed. Additionally, rapid antigen detection testing is not indicated in this patient as she has a cough and does not have cervical lymphadenopathy, tonsillar exudates, or palatal petechiae. All of these findings are not typical of GAS pharyngitis.

Answer C: Influenza testing and oseltamivir are indicated if the child had myalgias or high fevers that would make influenza more likely and if he presented within 2 days of symptom onset. Oseltamivir is only approved for treating influenza in uncomplicated cases if started within this 2-day window from symptom onset. Exceptions to this 2-day guideline include adults greater than 65 years of age, pregnant women, residents of long-term care facilities, American Indians, persons with BMI greater than 40 kg/m^2, and those receiving immunosuppressive medications.

Answer D: Obtaining a chest radiograph and respiratory virus panel can be done when a lower respiratory infection such as bacterial pneumonia is expected. However, viral infections are much more common than bacterial pneumonia in this age group. Additionally, this patient is not tachypneic, does not have evidence of increased work of breathing, and is not hypoxemic, all of which make bacterial pneumonia less likely.

Bullet Summary:
Viral pharyngitis in children is a clinical diagnosis consisting of fever, rhinorrhea, conjunctivitis, cough, sore throat, and pharyngeal erythema, and is treated with supportive care.