Pertinent Positives for Acute Viral Rhinosinusitis
Acute viral rhinosinusitis is diagnosed when symptoms last less than 10 days and include at least two of the following: nasal congestion/obstruction, purulent or colored nasal discharge, facial pressure/pain, and reduced sense of smell—without features suggesting bacterial infection. 1, 2
Cardinal Symptoms (Need ≥2 Present)
- Nasal obstruction or congestion is a major diagnostic criterion for acute rhinosinusitis 2
- Purulent or colored nasal discharge (anterior or posterior) is a major symptom, though color alone does NOT indicate bacterial infection 2, 3
- Facial pain or pressure, particularly over the sinuses, is a major symptom 2
- Reduced or loss of smell (hyposmia/anosmia) is a major diagnostic criterion 2
Temporal Pattern (Critical for Viral vs. Bacterial Differentiation)
- Symptoms lasting less than 10 days strongly suggest viral etiology 1, 2
- Gradual improvement of symptoms over 5-10 days is typical of viral infection, with symptoms peaking at days 3-5 2
- Symptoms present for fewer than 7 days make bacterial infection highly unlikely 1
Additional Supportive Features
- Sneezing, rhinorrhea, and nasal itching are common accompanying symptoms 4
- Cough (particularly daytime cough) may be present 2
- Sore throat is a typical associated symptom 4
- Low-grade fever or absence of high fever (temperature <39°C/102.2°F) supports viral etiology 2
Key Negative Findings (Absence Supports Viral Diagnosis)
- Absence of persistent symptoms ≥10 days without improvement (which would suggest bacterial infection) 1, 2
- Absence of severe symptoms such as high fever ≥39°C for ≥3 consecutive days, severe unilateral facial pain, or periorbital swelling 2, 5
- Absence of "double-sickening" pattern (initial improvement followed by worsening with new fever or substantially worse discharge/cough) 2
Critical Clinical Pitfall to Avoid
The presence of purulent or colored nasal discharge alone does NOT distinguish viral from bacterial rhinosinusitis and should never be used as the sole criterion for diagnosis or antibiotic prescription. 2 The yellow-green color reflects neutrophil presence and inflammatory enzymes that accumulate during both viral AND bacterial infections 2. Purulent discharge increases specificity for bacterial infection only when combined with other cardinal symptoms AND appropriate timing criteria (≥10 days duration or severe presentation) 2.
What NOT to Find (Red Flags Requiring Alternative Diagnosis)
- Periorbital edema or erythema suggests orbital complications 2
- Diplopia or vision changes indicate potential serious complications 2
- Severe headache, altered mental status, or meningeal signs suggest intracranial complications 2
- Unilateral severe facial pain with high fever may indicate acute bacterial rhinosinusitis requiring immediate treatment 5