What are the typical signs, supportive management, and red‑flag symptoms requiring medical attention for hand, foot, and mouth disease in children?

Hand, Foot, and Mouth Disease: Clinical Management

Hand, foot, and mouth disease (HFMD) is a self-limiting viral illness requiring supportive care only, with parents needing clear guidance on red-flag symptoms that warrant immediate medical attention, particularly neurological complications and dehydration. 1

Typical Clinical Presentation

Initial Symptoms

• Fever (often low-grade but can exceed 102.2°F/39°C) accompanied by malaise, sore throat, and irritability in toddlers 2, 3
• Constitutional symptoms typically precede the characteristic rash by 1-2 days 4

Characteristic Lesions

• Oral lesions: Painful vesicles and ulcers on the tongue, gums, and buccal mucosa 1
• Hand and foot lesions: Maculovesicular eruptions on palms, soles, and sometimes extending to legs and buttocks 1, 4
• Atypical presentations: Widespread exanthema beyond classic distribution, Gianotti-Crosti-like eruptions, or eczema coxsackium may occur, particularly with Coxsackievirus A6 1, 5

Supportive Management

Pain and Fever Control

• Acetaminophen or NSAIDs for limited duration to relieve pain and reduce fever 1
• Never use aspirin in children under 16 years due to Reye's syndrome risk 6

Oral Lesion Management

• Gentle oral hygiene with mild toothpaste 1
• Benzydamine hydrochloride oral rinse or spray every 3 hours, particularly before eating 1
• Barrier preparations such as Gengigel mouth rinse or Gelclair for pain control 1
• For severe oral involvement: Betamethasone sodium phosphate 0.5 mg dissolved in 10 mL water as rinse-and-spit solution 1-4 times daily 1
• White soft paraffin ointment to lips every 2 hours to prevent drying 1

Dietary Modifications

• Eliminate tomatoes, citrus fruits, hot drinks, and spicy, hot, raw, or crusty foods 1
• Encourage ample fluid intake to maintain hydration and keep mouth moist 1
• Offer cool, soft foods that are easier to tolerate

Skin Lesion Care

• Intensive moisturizing of hands and feet with urea-containing creams 1
• Zinc oxide application in thin layer to reduce itchiness, forming a protective barrier 1
• Avoid friction and heat exposure to affected areas 1
• For open sores on feet: wash daily with careful drying, avoid walking barefoot, wear cushioned footwear 1
• Do not use chemical agents or plasters to remove corns/calluses 1

Red-Flag Symptoms Requiring Immediate Medical Attention

Neurological Complications (Most Critical)

• Altered mental status or confusion 6
• Severe headache with meningismus (neck stiffness) 6
• Cranial nerve palsies 6
• Seizures, particularly complicated or prolonged 6
• Acute flaccid paralysis or myelitis 1, 2
• Encephalitis/meningitis signs: extreme lethargy, drowsiness beyond normal illness 6, 1

Cardiopulmonary Complications

• Signs of shock: extreme pallor, hypotension, floppy infant 6
• Respiratory distress: markedly raised respiratory rate, grunting, intercostal recession, cyanosis 6
• Myocardial dysfunction or cardiac arrhythmias (rare but serious) 7

Dehydration

• Severe dehydration from inability to drink due to painful oral lesions 6
• Vomiting > 24 hours 6
• Decreased urine output, dry mucous membranes, lethargy

Secondary Infection

• Increased redness, warmth, purulent drainage, or worsening pain at lesion sites 1
• Fever returning after initial resolution

Infection Control and Return to Activities

Infectious Period

• Most infectious during first week of illness, particularly when fever and skin lesions present 3
• Viral shedding continues up to 7 days in children and 5 days in adults after symptom onset 3

Prevention Measures

• Hand hygiene with soap and water is the single most important preventive measure (more effective than alcohol-based sanitizers) 1, 3
• Environmental cleaning of toys and objects that may be placed in children's mouths 1
• Avoid sharing utensils, cups, or food 1
• Exclude from swimming pools during acute illness 3

Return to Daycare/School Criteria

• Children can return once fever resolves and mouth sores heal, even if skin rash still present 1
• Exclusion based solely on healing skin lesions is unnecessary 1
• Some guidelines suggest waiting until no new lesions for 48 hours 3
• Continue hand hygiene vigilance as viral shedding may persist 3

Diagnostic Considerations

When Laboratory Confirmation Needed

• RT-PCR of vesicle fluid (highest viral load) is preferred diagnostic method 1
• Respiratory samples or stool specimens can also be used 1
• Laboratory confirmation typically reserved for severe cases, outbreaks, or atypical presentations 1

Critical Differential Diagnoses

• Herpes simplex virus (has antiviral treatment available, unlike HFMD) 1
• Kawasaki disease (diffuse erythema vs. vesicular lesions) 1
• Drug hypersensitivity reactions with palmar-plantar rash 1
• In atypical presentations: varicella, eczema herpeticum, erythema multiforme 5

Follow-Up and Late Manifestations

Expected Timeline

• Reassess after 2 weeks if lesions not improving with standard care 1
• Re-evaluate after 4 weeks if evidence of infection has not resolved; consider alternative diagnoses 1

Late Sequelae (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
• These represent delayed sequelae rather than active disease and require only reassurance 1

Special Populations

Immunocompromised Patients

• May experience more severe disease and require closer monitoring 1, 2
• Lower threshold for hospital evaluation

High-Risk Age Groups

• Children under 3 years have increased risk of severe complications including brain stem encephalitis 8
• Infants under 1 year should be seen by GP for any high fever with cough or influenza-like symptoms 6

Common Pitfalls to Avoid

• Do not routinely use topical antiseptic or antimicrobial dressings for HFMD foot lesions 1
• Do not soak feet in footbaths as this induces skin maceration and worsens open sores 1
• Do not delay evaluation if neurological symptoms develop, even if mild 6
• Do not exclude children unnecessarily from daycare based solely on presence of healing skin lesions 1