Chronic Rhinosinusitis (CRS)
The diagnosis is chronic rhinosinusitis (CRS), which requires 12 weeks or longer of purulent nasal drainage accompanied by nasal obstruction/swelling, plus objective documentation of sinonasal inflammation on examination or imaging 1, 2.
Diagnostic Criteria
To establish this diagnosis, you need both clinical symptoms AND objective findings:
Required Clinical Symptoms (≥12 weeks duration)
You must document two or more of the following, with at least one being mucopurulent drainage or nasal obstruction 2:
- Mucopurulent drainage (anterior, posterior, or both) - this is the purulent rhinorrhea you're observing
- Nasal obstruction/congestion - this corresponds to the intranasal mucosal swelling
- Facial pain/pressure/fullness
- Decreased sense of smell
Required Objective Documentation
You cannot diagnose CRS on symptoms alone - you must confirm inflammation through one of these methods 1:
- Anterior rhinoscopy or nasal endoscopy showing purulent mucus or edema in the middle meatus/anterior ethmoid region
- Nasal polyps in the nasal cavity or middle meatus
- CT imaging demonstrating paranasal sinus inflammation
Key Diagnostic Distinctions
Differentiate from Acute Bacterial Rhinosinusitis (ABRS)
ABRS presents with the same cardinal symptoms (purulent drainage + obstruction or facial pain) but lasts ≤4 weeks and typically follows one of these patterns 1, 3:
- Symptoms persist ≥10 days without improvement
- Symptoms worsen within 10 days after initial improvement ("double worsening")
Rule Out Other Causes
The chronic purulent rhinorrhea with intranasal swelling could also represent 4, 5:
- Retained foreign body (especially if unilateral symptoms)
- Allergic rhinitis (but typically presents with clear, not purulent, discharge)
- Nonallergic rhinitis (presents primarily with congestion and postnasal drainage, not purulence)
Clinical Pearls
Chronic purulent rhinorrhea and hyposmia together have an odds ratio of 3.8 for predicting CRS 4. The presence of purulent (not clear) discharge is critical - clear secretions suggest viral infection or allergic/nonallergic rhinitis rather than CRS.
The intranasal mucosal swelling you observe corresponds to the inflammatory edema that characterizes CRS. On examination, you may see 2:
- Edematous turbinates
- Purulent mucus in the middle meatus
- Possible nasal polyps
Common Pitfall
Do not diagnose CRS based on symptoms alone - the 2015 AAO-HNS guidelines explicitly require objective confirmation 1. Many patients report "sinus" symptoms, but without documented inflammation on examination or imaging, alternative diagnoses (migraine, tension headache, nonallergic rhinitis) should be considered.