Rewriting the Rules of Rhinosinusitis

Evidence-Based Diagnosis

Accurate diagnosis is key to the successful management of acute or chronic sinusitis. Establishing an appropriate diagnosis is the first step toward minimizing inappropriate, potentially harmful treatment and optimizing clinical outcomes.

The 2025 adult sinusitis update emphasizes the need for clinicians to distinguish acute bacterial sinusitis from acute sinusitis caused by a viral infection or acute noninfectious rhinosinusitis. Because evidence has shown that the vast majority of acute rhinosinusitis cases (approximately 90% to 98%, according to the Infectious Diseases Society of America) are viral, clinicians should only diagnose acute bacterial sinusitis if a patient has a combination of the three cardinal symptoms of acute rhinosinusitis (ARS)—purulent nasal drainage, nasal obstruction, facial pain/pressure/ fullness—for more than 10 days or if symptoms of ARS worsen within 10 days after initial improvement (Otol Head Neck Surg. 2025;173(S1):S1–S56). Practically speaking, this guidance means that ARS should not be diagnosed in anyone who has sinusitis symptoms for fewer than 10 days.

At present, however, it’s still incredibly common for patients with sinusitis symptoms who present to retail or walk-in clinics and urgent care settings to receive both a sinusitis diagnosis and prescription for antibiotics, said Spencer C. Payne, MD, professor of otolaryngology at the University of Virginia and chair of the 2025 medical guideline update group. That’s why it’s important for otolaryngologists to educate frontline physicians and healthcare providers about the latest guidelines. One way to do so, Dr. Payne said, is via one-on-one conversations with referring providers.

“On multiple occasions, I’ve reached out to primary providers and said something like, I noticed this patient was given antibiotics, but they haven’t met the criteria for a diagnosis of sinusitis. Here’s what the guidelines now say,” Dr. Payne said. “Most people have been receptive.”

Clinical diagnosis of chronic rhinosinusitis (CRS) should be confirmed with objective documentation of sinonasal inflammation via either anterior rhinoscopy, nasal endoscopy, or computed tomography. The updated guidelines acknowledge the fact that serum biomarkers (including IL-5, IL‐13, IL‐4, serum IgE, IL‐6, and IFN‐gamma) often indicate inflammation, but these biomarkers are not part of the current diagnostic criteria for CRS.

The inaugural surgical guidelines further underscore the importance of evidence-based diagnosis: The first key action statement says that surgeons should verify that established diagnostic criteria for CRS are met before recommending sinus surgery (Otol Head Neck Surg. 2025;172(S2):S1–S47).

Antibiotic Stewardship in Action

Watchful waiting is now the recommended course of action for acute sinusitis in adults.