What are the symptoms and treatment options for hand, foot, and mouth disease (HFMD) in adults, according to Australian guidelines?

Diagnosis and Management of Hand, Foot, and Mouth Disease in Adults

Hand, foot, and mouth disease (HFMD) in adults should be managed with supportive care focusing on symptom relief, as it is typically a self-limited viral illness lasting less than one week, though adults may experience more severe symptoms than children.

Clinical Presentation and Diagnosis

Initial Symptoms

• Fever is usually the first symptom (typically low-grade but can exceed 102.2°F/39°C), often accompanied by malaise, general discomfort, sore throat, and irritability 1
• Respiratory symptoms such as cough and rhinitis may accompany the classic presentation 2
• Gastrointestinal symptoms including nausea, vomiting, and diarrhea are occasionally reported 2

Characteristic Rash and Lesions

• The exanthem typically begins as small, pink macules that evolve to vesicular lesions, with a highly characteristic distribution on palms and soles 2
• Maculopapular or vesicular eruptions form on the palms and soles as well as in the oral cavity a few days after initial symptoms 3
• In adults, particularly with coxsackievirus A6 infections, symptoms may be more severe than the "classical" childhood presentation 3

Diagnostic Methods

• Diagnosis is primarily clinical based on the characteristic distribution of lesions 1
• When laboratory confirmation is needed, vesicle fluid samples have high viral loads and are ideal for testing with reverse transcriptase PCR (RT-PCR) 1
• Respiratory samples and/or stool specimens can also be used for diagnosis 1

Treatment Approach

Supportive Care

• Oral analgesics such as acetaminophen or NSAIDs for a limited duration to relieve pain and reduce fever 1
• Adequate hydration is essential, especially if oral lesions make drinking painful 4
• Mild toothpaste and gentle oral hygiene to manage oral lesions 1

Management of Specific Symptoms

For Oral Lesions/Stomatitis

• Early intervention for oral lesions 1
• Clean the mouth daily with warm saline mouthwashes 1
• Consider delaying normal activities until symptoms resolve for severe oral ulcers 1

For Skin Manifestations (Hand and Foot Lesions)

• Intensive skin care of hands and feet with moisturizing creams, such as urea cream/ointment 1
• Avoid friction and heat exposure to affected areas 1
• Zinc oxide can be applied to soothe inflamed areas and potentially reduce itchiness 1
• For nighttime relief, consider applying zinc oxide followed by loose cotton gloves to create an occlusive barrier 1

Monitoring for Complications

• While rare in adults, monitor for neurological complications such as encephalitis/meningitis, particularly with EV-71 infections 1, 5
• Watch for signs of secondary bacterial infections of skin lesions 1
• Be aware that nail dystrophies (e.g., Beau's lines or nail shedding) may occur weeks after initial symptom onset 6

Prevention and Control

• Hand hygiene is the most important preventive measure, with thorough handwashing with soap and water being more effective than alcohol-based hand sanitizers 1
• Environmental cleaning, particularly of frequently touched surfaces, is crucial in preventing spread 1
• Adults with HFMD should avoid close contact with others until fever resolves and mouth sores heal 1
• Avoid sharing utensils, cups, or food to prevent spread 1

Special Considerations for Adults

• Unlike in children, adults may have more severe symptoms and longer recovery time 7
• Immunocompromised adults may experience more severe disease and should be monitored closely 1
• Adults working in healthcare, childcare, or food service should be particularly cautious about returning to work until symptoms resolve 7

Return to Work Guidelines

• Adults can return to work once fever has resolved and mouth sores have healed, even if skin rash is still present 1
• Standard precautions and good hand hygiene practices should be followed, especially in healthcare settings 1

Common Pitfalls and Caveats

• HFMD in adults is often misdiagnosed due to its reputation as a childhood disease 7
• The rash on palms and soles is not unique to HFMD and can occur in other conditions, including drug hypersensitivity reactions, infective endocarditis, and certain infections 2
• Unlike chickenpox, HFMD vesicles are typically concentrated on hands, feet, and mouth rather than being widely distributed 2
• There is no specific antiviral therapy generally recommended for uncomplicated HFMD 3