What is the most likely diagnosis and recommended management for a 36‑year‑old man with a 5‑day history of sore throat, odynophagia, loss of voice, dry cough, watery rhinorrhea, cobblestone‑appearing posterior oropharynx, normal vital signs, no fever or cervical lymphadenopathy, and partial response to mucolytic‑cough suppressant?

Diagnosis and Management of Acute Viral Upper Airway Cough Syndrome (Laryngopharyngitis)

This patient has acute viral laryngopharyngitis with upper airway cough syndrome (UACS)—the most common cause of acute cough—and requires only symptomatic treatment; antibiotics are not indicated.

Most Likely Diagnosis

Acute viral laryngopharyngitis with upper airway cough syndrome (UACS). The clinical picture is classic for a viral upper respiratory infection:

• 5-day duration with watery rhinorrhea, throat pain, odynophagia, hoarseness ("no voice"), and dry cough strongly indicates a viral etiology 1
• Cobblestone appearance of the oropharynx is a characteristic finding of UACS due to lymphoid hyperplasia from postnasal drainage 1
• Absence of fever, normal vital signs (except borderline BP), and the presence of cough effectively rule out Group A streptococcal pharyngitis 2, 3, 4
• Cough is the single most important distinguishing feature that points away from bacterial pharyngitis toward viral infection 2, 3, 4

Why This Is UACS and Not Strep Throat

• UACS is the most common cause of both acute and chronic cough, either alone or in combination with other conditions 1
• The common cold is the most common condition afflicting mankind, making UACS the most common cause of acute cough 1
• Viral pharyngitis accounts for 70-85% of all acute pharyngitis cases in adults 3, 5, 4
• Group A Streptococcus accounts for only 5-15% of adult pharyngitis cases 3, 4

Next Steps: Diagnostic Approach

Do NOT Perform Strep Testing

Testing for Group A Streptococcus is not indicated in this patient because:

• The presence of cough strongly favors a viral etiology and effectively excludes streptococcal pharyngitis 2, 3, 4
• Testing should not be performed when viral features are present (cough, rhinorrhea, hoarseness) 2, 3
• Testing patients with obvious viral symptoms increases the likelihood of detecting harmless carriers rather than true infections 3

Blood Pressure Follow-Up

The incidental finding of BP 130/80 requires follow-up but is not an acute concern:

• This reading meets the definition of Stage 1 hypertension (systolic 130-139 or diastolic 80-89)
• Recommend home BP monitoring or return visit to confirm whether this represents true hypertension versus white-coat effect or acute illness-related elevation

Management Recommendations

Primary Treatment: Symptomatic Care Only

No antibiotics are indicated; provide symptomatic relief measures:

• Analgesics/antipyretics: Ibuprofen or acetaminophen for throat pain and any fever 1, 2
• Simple home remedies: Honey and lemon, which may be as effective as over-the-counter preparations 1
• Adequate hydration and throat lozenges for additional comfort 2
• Voluntary cough suppression: Simple conscious suppression of cough may reduce frequency through central modulation of the cough reflex 1

Cough Management

The patient's partial response to dextromethorphan + guaifenesin is appropriate:

• Continue dextromethorphan as needed for cough suppression; it has demonstrated efficacy in cough challenge studies 1
• Central antitussives like dextromethorphan are recommended when other measures fail 1
• Avoid opiate antitussives (codeine) due to significant adverse effects without superior efficacy 1

Expected Course and Red Flags

Reassure the patient that:

• Most viral pharyngitis and cough resolve within 7 days regardless of treatment 1, 6
• Symptoms persisting beyond 3 weeks but less than 8 weeks would be classified as postinfectious cough 1

Instruct the patient to return if:

• Symptoms worsen significantly or persist beyond 3-4 days without improvement, which may indicate suppurative complications 2
• Development of high fever, severe dysphagia, unilateral throat swelling, or difficulty breathing would require urgent reassessment for peritonsillar abscess or other complications 6
• Hemoptysis, prominent systemic illness, or significant breathlessness would mandate chest radiograph 1

Pathophysiology of UACS-Induced Cough

Understanding the mechanism helps explain the clinical presentation:

• Cough receptors in the hypopharynx and larynx are mechanically stimulated by secretions draining from the nose and sinuses 1
• The cough reflex in the upper airway may be more sensitive than normal in patients with UACS 1
• The cobblestone appearance represents lymphoid hyperplasia from chronic irritation by postnasal drainage 1

Common Pitfalls to Avoid

Do Not Prescribe Antibiotics

Antibiotics have no role in viral pharyngitis and acute viral cough:

• 60% or more of adults with sore throat are inappropriately prescribed antibiotics despite only 10% having streptococcal infection 4
• Treating without microbiologic confirmation leads to unnecessary antibiotic use and contributes to resistance 6, 3
• Antibiotics shorten symptom duration by only 1-2 days even in confirmed streptococcal cases 6

Do Not Misinterpret Physical Findings

The cobblestone appearance and pharyngeal erythema are nonspecific:

• These findings are relatively sensitive but not specific for UACS and are found in many patients with cough from other causes 1
• White patches and exudate can occur with viral infections and do not reliably distinguish bacterial from viral causes 3

Do Not Ignore the Hoarseness

Loss of voice (laryngitis) is an important clue:

• Hoarseness is commonly reported in patients with UACS 1
• Recent reports describe COVID-19-associated acute laryngitis with odynophagia and characteristic laryngoscopic findings 7, 8, 9
• While this patient's presentation is consistent with common viral laryngopharyngitis, if symptoms worsen dramatically (muffled speech, severe dysphagia, inspiratory stridor), urgent laryngoscopy would be needed to exclude laryngeal edema 9