What are the characteristics of the lesions in hand, foot, and mouth disease?

Characteristics of Lesions in Hand, Foot, and Mouth Disease

Hand, foot, and mouth disease (HFMD) is characterized by a maculopapular or papulovesicular rash on the hands and feet, along with painful oral ulcerations that typically resolve within 7-10 days without specific treatment.

Clinical Presentation of Lesions

Oral Lesions

• Painful oral ulcerations that typically appear first in the disease course 1
• Vesicular and ulcerative lesions primarily affecting:
  • Buccal mucosa
  • Hard palate
  • Tonsillar pillars
  • Pharynx 2
• Lesions begin as small erythematous areas that progress to painful ulcers
• These oral manifestations cause pain when swallowing and may lead to decreased oral intake 3

Skin Lesions

• Maculopapular or papulovesicular rash primarily affecting:
  • Palms of hands
  • Soles of feet
  • May also involve the buttocks and genitalia in some cases 1, 2
• The rash typically evolves from flat red spots (macules) to raised red spots (papules) to fluid-filled vesicles
• Lesions are generally non-itchy but may be painful or tender to touch
• Distribution is typically symmetric and concentrated on the extremities 4

Disease Course and Progression

Timing and Evolution

• Oral lesions usually appear first, followed by the cutaneous rash within 1-2 days
• Low-grade fever (37.8°C) often precedes or accompanies the rash 5
• Lesions typically resolve spontaneously within 7-10 days without scarring 3
• In some cases, particularly with Coxsackievirus A6 infections, delayed onychomadesis (nail shedding) and palmoplantar desquamation may occur during recovery 2

Atypical Presentations

Recent outbreaks of Coxsackievirus A6 have shown more extensive cutaneous involvement including:

• Vesicobullous and erosive eruptions
• Periorificial lesions
• Localization in areas of pre-existing atopic dermatitis ("eczema coxsackium")
• Petechial/purpuric eruptions 2

Differential Diagnosis

When evaluating lesions that might be HFMD, consider these alternative diagnoses:

• Herpes simplex virus infection
• Herpangina (primarily affects the posterior pharynx)
• Recurrent aphthous stomatitis
• Erythema multiforme
• Varicella (chickenpox)
• Stevens-Johnson syndrome (in severe cases) 3, 1

Complications

While most cases resolve without complications, be aware of potential serious outcomes:

• Neurologic complications (rare): meningitis, encephalitis
• Cardiopulmonary complications (very rare)
• Dehydration due to painful oral lesions limiting fluid intake 4

Management Approach

Treatment is primarily supportive:

• Hydration maintenance
• Pain relief with acetaminophen or ibuprofen as needed
• Topical oral pain relievers (though oral lidocaine is not recommended)
• No specific antiviral treatment is available 1

Prevention

The most effective prevention methods include:

• Thorough handwashing
• Disinfecting potentially contaminated surfaces and objects
• Avoiding close contact with infected individuals
• Proper disposal of nasal and oral secretions 1, 4

HFMD is highly contagious and transmitted through fecal-oral, oral-oral, and respiratory droplet contact, so proper hygiene practices are essential in preventing spread, particularly in childcare settings.