What are the differential diagnoses for a patient with pharyngitis, nasal congestion, cough, left-sided cervical lymphadenopathy, and dysphagia?

Differential Diagnoses for Pharyngitis with Nasal Congestion, Cough, Left Cervical Lymphadenopathy, and Dysphagia

Most Likely Viral Etiology

The presence of cough and nasal congestion strongly suggests viral pharyngitis, which accounts for the majority of pharyngitis cases and does not require antibiotic therapy. 1

• Viral pharyngitis is the most common cause when pharyngitis presents with cough, nasal congestion, and rhinorrhea, as these symptoms are characteristic of viral rather than bacterial infection 1
• Common viral pathogens include rhinovirus, coronavirus, adenovirus, parainfluenza, enterovirus, and influenza 1
• The presence of cough is a negative predictor for Group A Streptococcal (GAS) pharyngitis and strongly favors viral etiology 1, 2

Infectious Mononucleosis (Epstein-Barr Virus)

• Epstein-Barr virus frequently causes acute pharyngitis with prominent cervical lymphadenopathy, often bilateral but can be unilateral, and may present with dysphagia due to tonsillar enlargement 1
• Look specifically for generalized lymphadenopathy beyond cervical nodes, splenomegaly, and posterior cervical adenopathy in addition to anterior nodes 1, 3
• Dysphagia in this context may indicate significant tonsillar hypertrophy 3

Group A Streptococcal Pharyngitis (Must Exclude)

Despite the presence of cough suggesting viral etiology, you must formally exclude GAS pharyngitis because it requires antibiotic treatment to prevent suppurative complications and rheumatic fever. 1

• GAS pharyngitis typically presents with fever, tonsillar exudates, tender anterior cervical lymphadenopathy, and absence of cough 1, 2
• The presence of cough makes GAS less likely, but clinical diagnosis alone is unreliable and testing is required if other features are present 1, 4
• Apply the Centor criteria: fever by history, tonsillar exudates, tender anterior cervical adenopathy, and absence of cough 1, 2
• If ≥2 Centor criteria are present, perform rapid antigen detection test (RADT) or throat culture 1, 2
• If <2 Centor criteria, do not test or treat as GAS is unlikely 2, 5

Serious Suppurative Complications (Red Flags)

The presence of dysphagia is a red flag that requires evaluation for life-threatening deep space infections. 1, 3

Peritonsillar Abscess

• Presents with severe unilateral throat pain, dysphagia, drooling, "hot potato" voice, and trismus 1, 3
• Examine for uvular deviation away from the affected side and asymmetric tonsillar bulging 3
• Unilateral cervical lymphadenopathy is consistent with this diagnosis 3

Retropharyngeal Abscess

• Presents with dysphagia, drooling, neck stiffness, and refusal to extend neck 3
• More common in children but can occur in adults 3
• Requires urgent imaging if suspected 3

Lemierre Syndrome (Fusobacterium necrophorum)

• Rare but life-threatening condition presenting as severe pharyngitis in adolescents and young adults with subsequent internal jugular vein thrombophlebitis 1, 3
• Suspect in patients with severe pharyngitis, persistent fever, and unilateral neck swelling or tenderness 1
• F. necrophorum is implicated in 10-20% of endemic pharyngitis cases in adolescents 1
• Urgent diagnosis and treatment necessary to prevent septic emboli and death 1, 3

Epiglottitis

• Presents with dysphagia, drooling, muffled voice, and respiratory distress 3
• Patient often sits upright and forward (tripod position) 3
• Do not examine the throat if epiglottitis is suspected—secure airway first 3

Other Bacterial Causes

• Groups C and G β-hemolytic streptococci can cause pharyngitis similar to GAS but are less common 1
• Neisseria gonorrhoeae should be considered in sexually active individuals with pharyngitis, especially with appropriate exposure history 1
• Arcanobacterium haemolyticum causes pharyngitis with scarlatiniform rash, particularly in teenagers and young adults 1

Acute Retroviral Syndrome (HIV)

• Presents with pharyngitis, fever, lymphadenopathy, and often a maculopapular rash 3
• Consider in patients with appropriate risk factors and ask about recent high-risk exposures 3

Kawasaki Disease (Pediatric Consideration)

• If the patient is a child, consider Kawasaki disease presenting with pharyngitis, cervical lymphadenopathy, and conjunctivitis 3
• Look for additional criteria: rash, extremity changes, and mucosal changes 3

Diagnostic Algorithm

Step 1: Assess for life-threatening conditions requiring immediate intervention 1, 3

• Evaluate for drooling, severe dysphagia, respiratory distress, trismus, or neck swelling suggesting peritonsillar abscess, retropharyngeal abscess, or epiglottitis 1, 3
• If present, secure airway and obtain urgent imaging or ENT consultation 3

Step 2: Calculate Centor criteria 1, 2

• Fever by history (1 point)
• Tonsillar exudates (1 point)
• Tender anterior cervical adenopathy (1 point)
• Absence of cough (1 point) 1, 2

Step 3: Testing strategy based on Centor score 1, 2

• 0-1 criteria: Do not test or treat—viral etiology presumed 2, 5
• 2-3 criteria: Perform RADT; treat only if positive 2, 5
• 4 criteria: May treat empirically or test first 2, 5

Step 4: If viral features predominate (cough, nasal congestion, conjunctivitis) 1

• Provide symptomatic treatment only with analgesics, antipyretics, and supportive care 1, 2
• Do not prescribe antibiotics 1

Step 5: Consider infectious mononucleosis if 1, 3

• Prominent posterior cervical or generalized lymphadenopathy
• Severe tonsillar enlargement with dysphagia
• Fatigue and malaise out of proportion to pharyngitis
• Consider monospot or EBV serology 3

Critical Pitfalls to Avoid

• Do not rely on clinical diagnosis alone for GAS pharyngitis—the signs and symptoms of GAS and viral pharyngitis overlap too broadly for accurate clinical diagnosis 1
• Do not prescribe antibiotics for viral pharyngitis—patients with cough, nasal congestion, and rhinorrhea have viral illness and should not receive antibiotics 1
• Do not miss peritonsillar abscess or Lemierre syndrome by failing to examine for asymmetry, uvular deviation, trismus, or severe unilateral neck tenderness 1, 3
• Do not assume absence of fever excludes serious bacterial infection—not all patients with GAS or suppurative complications report fever 1, 4
• Do not perform throat examination if epiglottitis is suspected—this can precipitate complete airway obstruction 3