Differential Diagnosis and Management of Upper Respiratory Infection (URI)

Clinical Presentation and Diagnosis

The American College of Physicians suggests that rhinorrhea, nasal congestion, intermittent sneezing, and cough with clear to yellowish sputum are classic viral URI symptoms 1, 3
The absence of fever and symptom onset "a few days ago" fits the typical viral URI pattern, which peaks early and begins improving by days 3-7 4, 5
Yellowish sputum does not indicate bacterial infection—it reflects white blood cells and desquamated epithelium from the normal inflammatory response to viral infection 3, 4
Viral URIs are self-limited, typically resolving within 7-10 days, though symptoms can persist up to 2 weeks 1, 4

Postinfectious upper airway cough syndrome (UACS) can occur if symptoms have been present approaching 7-10 days, representing the natural progression of viral URI into postinfectious UACS 2
Acute viral bronchitis is defined by cough with sputum production lasting up to 3 weeks, but the absence of fever and short symptom duration make this less likely than simple viral URI 7
Acute bacterial rhinosinusitis requires one of three specific patterns: (1) symptoms persisting >10 days without improvement, (2) severe symptoms with high fever >39°C AND purulent discharge AND facial pain for ≥3 consecutive days, or (3) "double sickening" (worsening after initial improvement) 1, 2, 5

The American Academy of Family Physicians recommends that antibiotics are not indicated for viral URI, even with yellowish sputum, and cause more harm than benefit 1, 7
First-generation antihistamine (e.g., diphenhydramine, chlorpheniramine) combined with oral decongestant (pseudoephedrine) is the evidence-based treatment for postinfectious UACS 2
Topical decongestants should be limited to 3-5 days maximum to avoid rebound congestion 6
Saline nasal irrigation provides relief without rebound effects 1
Intranasal ipratropium bromide can help with profuse watery rhinorrhea 1, 6

Symptoms typically last 7-10 days but can persist up to 2 weeks 1, 4
Viral shedding peaks in the first 2-3 days and substantially decreases by day 7-10 4
Red flags requiring re-evaluation include symptoms persisting >10 days without improvement, worsening after initial improvement, high fever >39°C with severe unilateral facial pain, and severe headache with neck stiffness, vision changes, or mental status changes 1, 2