What initial investigations should be performed in a patient suspected of having a peritonsillar abscess?

For a patient suspected of having a peritonsillar abscess, the primary initial action from a General Practice perspective is to arrange hospital admission urgently ¹. This is crucial due to the significant risk of airway compromise or rupture of the abscess ¹.

While specific initial investigations for peritonsillar abscesses are not detailed for primary care within the provided guidelines, investigations for other types of abscesses and suspected sepsis offer insight into likely subsequent steps in secondary care:

• Imaging: For other localised abscesses, such as breast abscesses or tuberculous abscesses, ultrasound or other appropriate imaging is used for diagnosis and to identify collections of pus ²,³. This approach would likely be considered for a peritonsillar abscess to confirm the diagnosis and guide management ²,³.
• Aspiration and Culture: If an abscess is confirmed and drained, fluid from the abscess would typically be cultured to guide the choice of antibiotic treatment ². For localised tuberculous abscesses, aspirate is used for microscopy, culture, and cytology ³.
• Tailored Investigations: Investigations for the source of infection should be tailored to the person's clinical history and examination findings, especially if sepsis is suspected ⁴.