What is the difference between herpangina and hand, foot, and mouth disease?

Difference Between Herpangina and Hand, Foot, and Mouth Disease

Herpangina and hand, foot, and mouth disease (HFMD) are both enteroviral infections that differ primarily in the distribution of their lesions: herpangina causes vesicles and ulcers confined to the posterior oropharynx (soft palate, uvula, tonsillar pillars), while HFMD produces oral lesions throughout the mouth plus the characteristic vesicular rash on the hands, feet, and buttocks. 1, 2, 3

Causative Agents

Both conditions are caused by human enteroviruses, with significant overlap in serotypes:

• Herpangina is most commonly caused by Coxsackievirus A10, A6, A16, and Enterovirus 71 (EV-A71), with 17 different serotypes identified in surveillance studies 3
• HFMD is caused by similar enteroviruses including EV-A71 (17.4% of cases), Coxsackievirus A16 (4.4%), and A10 (3.1%), with 21 different serotypes documented 3
• EV-A71 is associated with more severe outbreaks and neurological complications in both conditions, particularly in Asia 1, 2

Clinical Presentation Differences

Location of Lesions

• Herpangina: Vesicles and ulcers are strictly limited to the posterior oral cavity—soft palate, uvula, tonsillar pillars, and posterior pharynx 2, 3
• HFMD: Oral lesions occur throughout the mouth (not just posterior) plus vesicular rash on palms, soles, buttocks, and may involve widespread exanthema on the legs 1, 2

Fever Patterns

• Herpangina patients have significantly higher body temperatures and higher incidence of fever compared to HFMD patients (P < 0.0001 and P < 0.05, respectively) 3
• HFMD typically presents with low-grade fever, though it can exceed 102.2°F/39°C 4

Overlapping Presentations

• In clinical practice, 48% of herpangina cases also show clinical signs of HFMD, making the distinction sometimes blurred 5
• The predominant clinical presentation in one outbreak was herpangina (63.8%), with nearly half showing concurrent HFMD features 5

Diagnostic Approach

• Clinical diagnosis is primarily based on the characteristic distribution of lesions 4, 6
• Laboratory confirmation via reverse transcriptase PCR (RT-PCR) of vesicle fluid, throat swabs, or stool specimens can identify the specific enterovirus serotype 1, 2
• Vesicle fluid samples have the highest viral loads and are ideal for testing 1

Differential Diagnosis Considerations

Both conditions must be distinguished from:

• Herpes simplex virus infection: HSV has available antiviral treatment whereas herpangina/HFMD do not; this is a critical distinction 1, 4
• Drug hypersensitivity reactions: Can cause palmar-plantar rash but lack vesicular morphology 7, 8
• Syphilis and meningococcemia: Can present with palmar-plantar involvement 7, 8
• Recurrent aphthae and erythema multiforme: Must be considered in the differential 6

Complications

• Both conditions can cause neurological complications including encephalitis/meningitis, acute flaccid myelitis, and acute flaccid paralysis, particularly with EV-A71 1, 2
• The case severity rate in China has been estimated at 1%, with a case fatality rate of 0.03%; EV-A71 was involved in more than 90% of fatal cases 2
• Delayed cutaneous manifestations such as onychomadesis (nail shedding) and acral desquamation may occur weeks after either condition 2

Management

Treatment is identical for both conditions and is purely supportive:

• Oral analgesics: Acetaminophen or NSAIDs for pain and fever relief 1
• Oral care: Benzydamine hydrochloride oral rinse or spray every 3 hours before eating; chlorhexidine oral rinse twice daily 4
• Skin care: Moisturizing creams with urea for hand/foot lesions; zinc oxide for itchiness 1, 4
• Hydration: Critical given painful oral lesions may reduce oral intake 1

Epidemiology and Prevention

• Both conditions occur predominantly in summer and autumn in temperate climates 2, 5
• Hand hygiene is the most important preventive measure, with soap and water being more effective than alcohol-based sanitizers 1
• Children can return to daycare once fever resolves and mouth sores heal, even if skin rash persists 1
• Adults are most infectious during the first week, with viral shedding continuing up to five days after symptom onset 4

Critical Pitfalls to Avoid

• Do not assume herpangina is less serious than HFMD—both can cause severe neurological complications with EV-A71 2, 3
• Do not exclude the diagnosis based on atypical presentations, as widespread exanthema beyond classic distribution may occur 1
• Do not confuse either condition with herpes simplex virus, as this distinction affects treatment decisions 1, 4
• Monitor immunocompromised patients closely, as they may experience more severe disease 1, 4