What is the appropriate treatment for a patient presenting with rashes on the hands and soles of the feet, along with mouth sores?

Hand, Foot, and Mouth Disease: Diagnosis and Treatment

This presentation is classic for hand, foot, and mouth disease (HFMD), most commonly caused by enteroviruses such as Coxsackievirus A16 or Enterovirus 71, and treatment is entirely supportive with oral analgesics and topical measures. 1

Immediate Diagnostic Considerations

Before confirming HFMD, you must exclude life-threatening conditions that can present with similar palmar-plantar rashes and oral lesions:

Critical Rule-Outs

Rocky Mountain Spotted Fever (RMSF) requires immediate exclusion, as it presents with fever and rash on hands/feet with 5-10% mortality if untreated. 2 Key distinguishing features:

• RMSF rash begins as blanching pink macules that evolve to petechiae, not vesicles 2
• Systemic toxicity (severe headache, myalgias, altered mental status) is prominent 2
• Start doxycycline immediately if RMSF cannot be excluded—do not wait for the classic triad of fever, rash, and tick bite 2

Meningococcemia presents with rapidly progressive petechial/purpuric rash and requires emergent ceftriaxone. 2 The rash progresses within hours, not days. 2

Kawasaki disease must be considered in children with fever ≥5 days plus rash on extremities. 3 However, Kawasaki presents with diffuse erythema and edema of hands/feet, not vesicular lesions, and includes bilateral conjunctival injection without exudate. 3

Secondary syphilis can cause palmar-plantar rash but is typically maculopapular, not vesicular, and lacks oral vesicles. 2

Confirming HFMD Diagnosis

HFMD is a clinical diagnosis based on the characteristic triad:

• Vesicular lesions on hands and feet (palms and soles specifically) 1
• Painful oral ulcers (typically on tongue, buccal mucosa, palate) 1
• Fever (common constitutional symptom) 1

The rash may extend beyond classic distribution to involve legs and buttocks. 1 Lesions on hands, feet, and mouth are pathognomonic for enteroviral infections. 3

Laboratory confirmation is not routinely needed but can be obtained via RT-PCR of vesicle fluid (highest viral load), respiratory samples, or stool specimens if diagnosis is uncertain. 1

Treatment Protocol

Symptomatic Management

Oral analgesics are first-line:

• Acetaminophen or NSAIDs for limited duration to relieve pain and reduce fever 1
• Do NOT use aspirin in children due to Reye's syndrome risk

Oral lesion care:

• Apply white soft paraffin ointment to lips every 2 hours to prevent drying 1
• Benzydamine hydrochloride oral rinse or spray every 3 hours, particularly before eating 1
• Chlorhexidine oral rinse twice daily as antiseptic 1
• Warm saline mouthwashes or oral sponge for comfort 1
• For severe oral involvement: betamethasone sodium phosphate mouthwash four times daily 1
• Use mild toothpaste and gentle oral hygiene 1

Skin care for hand and foot lesions:

• Intensive moisturizing with urea-containing creams 1
• Avoid friction and heat exposure to affected areas 1
• Do NOT use chemical agents or plasters to remove lesions 1
• For itchiness: zinc oxide 20% applied as thin layer after gentle cleansing, can repeat as needed 1
• Avoid applying zinc oxide to open or weeping lesions 1

Management of Open Sores on Feet

If vesicles have ruptured:

• Wash feet daily with careful drying, particularly between toes 1
• Avoid walking barefoot; wear appropriate cushioned footwear 1
• Do NOT soak feet in footbaths—this causes maceration and worsens open sores 1
• Monitor for secondary infection: increased redness, warmth, purulent drainage, or worsening pain 1
• Do NOT use topical antiseptic or antimicrobial dressings routinely 1

Prevention and Infection Control

Hand hygiene is the single most important preventive measure:

• Thorough handwashing with soap and water is more effective than alcohol-based sanitizers 1
• Clean toys and objects that may be placed in children's mouths 1

Isolation guidelines:

• Children can return to daycare once fever resolves and mouth sores heal, even if skin rash persists 1
• Exclusion based solely on healing skin lesions is unnecessary 1
• Avoid sharing utensils, cups, or food 1

Follow-Up and Complications

Reassess after 2 weeks if lesions are not improving with standard care. 1

Re-evaluate and consider alternative diagnoses if symptoms have not resolved after 4 weeks. 1

Expected late manifestations (not requiring treatment):

• Periungual desquamation typically begins 2-3 weeks after fever onset 1
• Beau's lines (deep transverse nail grooves) may appear 1-2 months after fever onset 1

Rare but serious complications (particularly with Enterovirus 71):

• Neurological complications: encephalitis/meningitis, acute flaccid myelitis, acute flaccid paralysis 1
• Immunocompromised patients may experience more severe disease and require close monitoring 1

Critical Pitfalls to Avoid

• Do NOT delay treatment for RMSF while waiting for laboratory confirmation if clinical suspicion exists 2
• Do NOT exclude serious bacterial infections based on absence of systemic toxicity alone 2
• Do NOT use antiviral medications—HFMD has no specific antiviral treatment, unlike herpes simplex virus 1
• Do NOT restrict activities unnecessarily once fever and oral lesions resolve 1