A 14-year-old boy comes to the emergency department due to sore throat and fever. He started having a mild sore throat after returning from summer camp approximately a week ago, and it has progressively worsened in the last 2 days. The patient has difficulty swallowing and an earache but no cough or shortness of breath. His voice is muffled. Temperature is 38.8 C (101.8 F), blood pressure is 118/74 mm Hg, and pulse is 104/min. There is no neck pain on extension or stiffness. Enlarged and tender cervical lymph nodes are present. The patient is unable to fully open his mouth, but examination of the oral cavity shows pooling of saliva, a large right tonsil with swelling of the right soft palate, and deviation of the uvula to the left. Ear examination shows normal tympanic membranes. Which of the following is the most appropriate next step in diagnosis of this patient?
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This patient's presentation is most concerning for a peritonsillar abscess (PTA), an acute bacterial infection of the region between the tonsil and the pharyngeal muscles. The infection begins as persistent tonsillitis/pharyngitis (eg, 2 weeks of sore throat in this patient) and progresses (eg, fever, worsening sore throat) to cellulitis/phlegmon, with pus collecting into an abscess within a few days of symptom onset. PTA is most common in older adolescents and young adults; drug or alcohol use increases the risk.
In addition to severe (often unilateral) sore throat and fever, clinical examination shows a muffled ("hot potato") voice, trismus (eg, inability to open the mouth fully, due to inflammation of the pterygoid muscles), dysphagia, and unilateral swelling of the soft palate with uvular deviation. This presentation is sufficient to diagnose and treat a PTA; no additional diagnostic testing is needed, particularly when there is no evidence of impending airway obstruction (eg, tripod position, stridor) or deep neck space infection (eg, chest pain, neck stiffness). Associated findings can include earache, lymphadenopathy, and pooling of saliva.
Treatment of PTA involves needle aspiration or incision and drainage plus antibiotic therapy to cover group A hemolytic Streptococcus and respiratory anaerobes.
(Choice A) CT scan of the neck is indicated only if there are concerning signs that a PTA has spread to involve deep spaces of the neck (eg, retropharyngeal or parapharyngeal abscess). In some centers, ultrasound is used to confirm the diagnosis of PTA if it is uncertain (eg, phlegmon vs abscess), but CT scan is not usually necessary, especially in this patient with a very classic history and examination findings.
(Choice B) Lateral neck radiographs are often obtained for suspected epiglottitis. Although epiglottitis can present with fever, dysphagia, severe sore throat, and muffled voice, pharyngeal findings are typically normal.
(Choice C) Lymph nodes biopsies are invasive and not usually helpful in the setting of acute infections, which can cause reactive lymph node enlargment regionally (eg, cervical in the case of PTA). If lymph node swelling persists (eg, >3-4 weeks), biopsy may be indicated to rule out certain conditions (eg, malignancy).
(Choice D) Infectious mononucleosis (often diagnosed by Monospot test) is characterized by the triad of fever, pharyngitis, and posterior cervical lymphadenopathy. Mononucleosis is not typically complicated by abscess formation (eg, deviation of uvula); the pharynx typically looks injected with or without tonsillar exudates.
Educational objective:
Peritonsillar abscess is characterized by progressive fever and (often unilateral) pharyngeal pain; examination findings include trismus, muffled voice, and swelling of the soft palate with uvular deviation. Abscesses with a classic presentation can usually be diagnosed clinically. Treatment involves needle aspiration or incision and drainage plus antibiotic therapy.