Diagnosis and Management of Acute Viral Upper Respiratory Infection
Most Likely Diagnosis
This patient has an acute viral upper respiratory infection (URI), the single most common cause of acute cough, runny nose, and sinus pressure. 1 The symptom triad of runny nose, cough, and sinus pressure is classic for the common cold syndrome, which accounts for the vast majority of acute URTIs. 1, 2
Why This is NOT Bacterial Sinusitis
Do not diagnose bacterial sinusitis during the first 10 days of symptoms unless there is severe presentation. 1, 3 The American Academy of Otolaryngology-Head and Neck Surgery explicitly states that bacterial sinusitis should only be diagnosed when: (1) symptoms persist ≥10 days without improvement, (2) severe symptoms are present (high fever >39°C, severe unilateral facial pain), or (3) symptoms worsen after initial improvement within 5-7 days ("double-worsening"). 3, 4
Sinus pressure and congestion in the first week are viral, not bacterial. Studies show 87% of patients with recent-onset colds have abnormal sinus CT scans, yet 79% resolve spontaneously without antibiotics by days 13-20. 1 This demonstrates that imaging abnormalities and sinus symptoms during acute viral URI do not indicate bacterial infection. 1
Green or yellow mucus does NOT indicate bacterial infection. Mucus color relates to neutrophil presence, not bacteria, and occurs normally during viral infections. 3
Evidence-Based Treatment Protocol
First-Line Symptomatic Management
Treat with a first-generation antihistamine/decongestant combination (e.g., brompheniramine with sustained-release pseudoephedrine). 1 This combination has demonstrated statistically significant improvement in cough, postnasal drip, and throat clearing in randomized controlled trials. 1
Additional symptomatic measures include:
- Naproxen can decrease cough severity. 1
- High-volume nasal saline irrigation for mucociliary clearance. 3
- Acetaminophen or ibuprofen for pain/fever. 2, 5
- Throat lozenges and warm saline gargles for throat discomfort. 2
What NOT to Do
Do not prescribe newer-generation nonsedating antihistamines—they are ineffective for viral URI cough. 1 Only first-generation antihistamines with anticholinergic properties work for this indication. 1
Do not prescribe antibiotics. Viral URIs account for 98-99.5% of acute rhinosinusitis cases. 3 The number needed to treat with antibiotics is 18, while the number needed to harm is 8, demonstrating poor benefit-to-risk ratio. 4, 2
Expected Natural History and Return Precautions
Symptoms typically improve within 7-10 days, but 25% of patients have persistent cough and upper airway symptoms at day 14. 1 This represents postinfectious upper airway cough syndrome (UACS), not bacterial infection. 4
Instruct the patient to return if:
- Symptoms persist beyond 10 days without any improvement 3, 4
- Symptoms worsen after initial improvement within 5-7 days 3, 4
- Fever >39°C (102.2°F) develops 2, 6
- Severe unilateral facial pain/swelling occurs 4
- Vision changes, severe headache with neck stiffness, or mental status changes develop (indicating potential complications requiring urgent evaluation) 4, 2
Critical Pitfall to Avoid
The most important pitfall is prescribing antibiotics based on symptom duration alone or the presence of colored nasal discharge. 3, 4 Only 0.5-2% of acute rhinosinusitis cases are actually bacterial, and 60% of presumed bacterial cases resolve spontaneously without antibiotics. 3 Antibiotic overuse for viral URIs is the leading cause of inappropriate antibiotic prescribing in adults. 6
If Symptoms Persist Beyond 10 Days
At day 10-14, if symptoms have not improved at all, consider bacterial sinusitis and initiate amoxicillin 500mg three times daily for 10-14 days. 3, 7 Amoxicillin covers Streptococcus pneumoniae and Haemophilus influenzae, the most common bacterial pathogens. 3, 8 If no improvement by day 7 of antibiotic therapy, switch to high-dose amoxicillin-clavulanate to cover beta-lactamase-producing organisms. 3, 8