A case of peritonsillar abscess: a diagnostic challenge aided by point-of-care ultrasound

AbstractA 27-year-old man with no medical history developed a fever and sore throat 5 days before visiting a primary care doctor. He was admitted to our hospital due to worsening symptoms, with a fever of 38.3ºC, redness of the pharynx, left tonsillar hypertrophy, uvular deviation to the right, and left submandibular lymph node enlargement with tenderness. Plain computed tomography (CT) revealed an enlarged left tonsil and lymph node. As it was difficult to differentiate between peritonsillar abscess (PTA) and peritonsillar cellulitis by plain CT, bedside cervical ultrasonography as point-of-care ultrasound (POCUS) was performed. A low echogenic area was observed in the center of the image. The mass with a low signal area on contrast-enhanced CT (CECT) was diagnosed as PTA. The patient was transferred to the otolaryngology department for pus drainage and was discharged 5 days later.Complications of PTA are rare but potentially fatal, warranting early diagnosis and prompt, appropriate management. CECT is useful for the diagnosis of PTA, but given the risk of complications by contrast agents and radiation, appropriate patient selection is important when performing CECT. POCUS was useful in diagnosing PTA that could not be diagnosed by plain CT.