In a healthy 20‑year‑old female with a one‑week history of watery rhinorrhea, nasal congestion, glabellar‑temporal headache worse in the morning, productive green cough and low‑grade fever, and examination showing boggy congested turbinates without erythema, what is the most likely diagnosis and appropriate next steps?

Acute Viral Rhinosinusitis (Likely Progressing to Post-Viral Phase)

This patient has acute viral rhinosinusitis at 7 days duration that has not yet met criteria for acute bacterial rhinosinusitis, and should be managed with intranasal corticosteroids, saline irrigation, and symptomatic care—antibiotics are not indicated at this time. 1

Diagnosis

The clinical picture is consistent with uncomplicated viral upper respiratory infection:

• Symptoms lasting exactly 7 days without worsening do not meet the threshold for acute bacterial rhinosinusitis (ABRS), which requires either ≥10 days of persistent symptoms OR worsening after 5-7 days of initial improvement. 2, 1, 3

• The green phlegm and purulent nasal discharge do NOT indicate bacterial infection—purulent color reflects neutrophil content and occurs normally in viral rhinosinusitis as secretions transition from clear to purulent and back to clear during the natural course of viral URI. 2, 1

• The low-grade fever (37°C) and headache are consistent with viral infection, as fever in uncomplicated viral URIs typically occurs early and resolves within 24-48 hours, with respiratory symptoms becoming more prominent afterward. 2

• Boggy congested turbinates without erythema are nonspecific findings that do not distinguish viral from bacterial disease. 2

• The temporal pattern is classic for viral URI: initial watery rhinorrhea and congestion, followed by thickening of secretions and development of productive cough—all within the expected 5-10 day course of viral infection. 2, 1

Immediate Management Plan

Start intranasal corticosteroid immediately:

• Mometasone furoate 200 µg (2 sprays per nostril) twice daily significantly improves total symptom scores, headache, facial pain, and congestion compared to placebo in acute viral rhinosinusitis. 1

• Do not wait until day 10 to start intranasal steroids—they can be initiated immediately for symptomatic relief. 1

Add high-volume saline nasal irrigation:

• Saline irrigation improves mucociliary clearance and is recommended as adjunctive therapy. 4, 1

Provide symptomatic relief:

• Analgesics (paracetamol or NSAIDs) for headache and facial pain. 1

• Adequate hydration, rest, warm facial compresses, steamy showers, and sleeping with head elevated 30-45° improve sinus drainage and comfort. 1

• Short-term decongestants (3-5 days maximum) may provide temporary relief but must be limited to avoid rebound congestion. 1

Discontinue the current combination medications (Neozep, Saridon) and replace with the targeted regimen above.

Critical Follow-Up Timeline

Reassess at day 10-14 (3-7 days from now):

• If symptoms persist without improvement at day 10-14, diagnose ABRS and initiate antibiotics. 1, 3

• If symptoms worsen at ANY time before day 10 (double worsening), this also meets criteria for ABRS and requires antibiotics. 1, 3

Criteria for "double worsening" that would trigger immediate antibiotic therapy:

• New onset or worsening fever
• Significant increase in facial pain/pressure
• Marked increase in purulent nasal discharge
• Any of these occurring after initial improvement 2, 1

Antibiotic Protocol (Only if ABRS Criteria Met)

First-line antibiotic when indicated:

• Amoxicillin 500 mg three times daily for 10-14 days is the preferred initial agent due to efficacy, safety, and cost-effectiveness. 1, 3, 5

If no improvement after 3-5 days of amoxicillin:

• Switch to high-dose amoxicillin-clavulanate (2000 mg/125 mg twice daily) to cover β-lactamase-producing organisms (H. influenzae, M. catarrhalis). 1

For penicillin allergy:

• Doxycycline, trimethoprim-sulfamethoxazole, or macrolides 1

Red Flags Requiring Urgent Evaluation

Instruct the patient to return immediately if she develops:

• Periorbital edema, erythema, swelling, proptosis, abnormal eye movements, or vision changes (orbital complications) 1

• Severe headache with altered mental status, neck stiffness, cranial nerve deficits (intracranial extension) 1

• Facial swelling or erythema over the involved sinus 1

• High fever >39°C with severe unilateral facial pain 1

Why Imaging is NOT Indicated

Do not order sinus X-rays or CT scan at this time:

• Routine imaging cannot distinguish viral from bacterial rhinosinusitis, and up to 87% of viral URIs show sinus involvement on imaging. 2, 1, 3

• CT should be reserved for suspected complications (orbital/intracranial extension) or treatment failure after 21-28 days of appropriate therapy. 1

Patient Education

Explain the expected course:

• Viral rhinosinusitis typically resolves within 7-10 days with symptomatic care; complete resolution may take up to 2 weeks. 1

• The green phlegm is normal in viral infections and does not mean she needs antibiotics. 2, 1

• Antibiotics are ineffective for viral illness and contribute to antimicrobial resistance. 1

Return precautions:

• Come back if symptoms persist beyond 10 days total, worsen at any time, or if any red-flag symptoms develop. 1

Common Pitfall to Avoid

The most common error is prescribing antibiotics based on purulent discharge alone—this leads to unnecessary antibiotic exposure, as purulent nasal discharge occurs in both viral and bacterial rhinosinusitis and cannot differentiate between the two. 2, 1 The key distinguishing features are duration (≥10 days) or worsening after initial improvement, neither of which this patient has met yet. 2, 1, 3